# December 2011, Volume 20, Number 4

**V. Prochazka, P. Pollak, J. Zdansky, J. Nouza**
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Performance of Czech Speech Recognition with Language Models Created from Public Resources

In this paper, we investigate the usability of publicly available n-gram corpora for the creation of language models (LM) applicable for Czech speech recognition systems. N-gram LMs with various parameters and settings were created from two publicly available sets, Czech Web 1T 5-gram corpus provided by Google and 5-gram corpus obtained from the Czech National Corpus Institute. For comparison, we tested also an LM made of a large private resource of newspaper and broadcast texts collected by a Czech media mining company. The LMs were analyzed and compared from the statistic point of view (mainly via their perplexity rates) and from the performance point of view when employed in large vocabulary continuous speech recognition systems. Our study shows that the Web1T-based LMs, even after intensive cleaning and normalization procedures, cannot compete with those made of smaller but more consistent corpora. The experiments done on large test data also illustrate the impact of Czech as highly inflective language on the perplexity, OOV, and recognition accuracy rates.

- NOUZA, J., ZDANSKY, J., DAVID, P. Fully automated approach to broadcast news transcription in Czech language. Text, Speech and Dialogue: Lecture Notes in Computer Science, 2004, vol. 3206/2004, p. 401 - 408.
- VANEK, J., PSUTKA, J. Gender-dependent acoustic models fusion developed for automatic subtitling of parliament meetings broadcasted by the Czech TV. Text, Speech and Dialog: Lecture Notes in Computer Science, 2010, vol. 6231/2010, p. 431- 438.
- PSUTKA, J., PSUTKA, J., IRCING, P., HOIDEKR, J. Recognition of spontaneously pronounced TV ice-hockey commentary. In Proceedings of ISCA & IEEE Workshop on Spontaneous Speech Processing and Recognition. Tokyo (Japan), 2003, p. 83 - 86.
- IRCING, P., KRBEC, P., HAJIC, J., PSUTKA, J., KHUDANPUR, S., JELINEK, F., BYRNE, W. On large vocabulary continuous speech recognition of highly inflectional language - Czech. In Proceedings of INTERSPEECH. Aalborg (Denmark), 2001, p. 487 - 490.
- NOUZA, J., ZDANSKY, J., CERVA, P., KOLORENC, J. A System for information retrieval from large records of Czech spoken data. Text, Speech and Dialogue: Lecture Notes in Computer Science, 2006, vol. 4188/2006, p. 485 - 492.
- The Hidden Markov Model Toolkit (HTK). Version 3.4.1. 2009. [Online] Available at: http://htk.eng.cam.ac.uk.
- BRANTS, T., FRANZ, A. Web 1T 5-gram, 10 European languages, version 1. Philadelphia: Linguistic Data Consortium, 2009. [Online] Available at: http://www.ldc.upenn.edu.
- BRANTS, T., FRANZ, A. Web 1T 5-gram, English, version 1. Philadelphia: Linguistic Data Consortium, 2006. [Online] Available at: http://www.ldc.upenn.edu.
- ISLAM, A., INKPEN, D. Real-word spelling correction using Google Web 1T n-gram with backoff. In International Conference on Natural Language Processing and Knowledge Engineering NLPKE 2009. Dalian (China), 2009, p. 1- 8.
- NULTY, P., COSTELLO, F. Using lexical patterns in the Google Web 1T corpus to deduce semantic relations between nouns. In Proceedings of the Workshop on Semantic Evaluations: Recent Achievements and Future Directions SEW 2009. Boulder (USA), 2009, p. 58 - 63.
- TANDON, N., DE MELO, G. Information extraction from webscale n-gram data. In Web N-gram Workshop : Workshop of the 33rd Annual International ACM SIGIR Conference on Research and Development in Information Retrieval. Geneva (Switzerland), 2010, p. 8 - 15.
- ZWARTS, S., JOHNSON, M. The impact of language models and loss functions on repair disfluency detection. In Proceedings of the 49th Annual Meeting of the Association for Computational Linguistics on Human Language Technologies. Portland (USA), 2011, p. 703 - 711.
- DEKANG LIN, et al. New tools forWeb-scale n-grams. In Proceedings of the Seventh International Conference on Language Resources and Evaluation LREC’10. Valetta (Malta), 2010, p. 19 - 21.
- GUTHRIE, D., HEPPLE, M. Storing the web in memory: space efficient language models with constant time retrieval. In Proceedings of the 2010 Conference on Empirical Methods in Natural Language Processing EMNLP 10. Cambridge (USA), 2010, p. 262 - 272.
- YURET, D. Smoothing a tera-word language model. In Proceedings of the 46th Annual Meeting of the Association for Computational Linguistics on Human Language Technologies: Short Papers. Singapore, 2008, p. 141 - 144.
- Czech National Corpus - SYN2006PUB. 2006. [Online] Available at: http://ucnk.ff.cuni.cz/english/syn2006pub.php.
- PROCHAZKA, V., POLLAK, P. Analysis of Czech Web 1T 5-gram corpus and its comparison with czech national corpus data. Text, Speech and Dialogue: Lecture Notes in Computer Science, 2010, vol. 6231/2010, p. 181 - 188.
- Institute of the Czech National Corpus. [Online] 2010. Available at: http://www.korpus.cz.
- GNU Aspell. [Online] Cited 2010-11-17. Available at: http:// aspell.net/.
- STOLCKE, A. SRILM – An extensible language modeling toolkit. In Proceedings of the 7th International Conference on Spoken Language Processing ICSLP 2002. Denver (USA), 2002, p. 901 - 904.
- Newton Media. [Online] 2010. Available at: http://www. newtonmedia.cz.
- NOVAK, J. R., DIXON, P. R., FURURI, S. An empirical comparison of the T3, Juicer, HDecode and Sphinx3 decoders. In Proceedings of 11th Annual Conference of the International Speech Communication Association INTERSPEECH 2010. Makuhari (Japan), 2010, p. 1890 - 1893.
- NOUZA, J., ZDANSKY, J., CERVA, P., SILOVSKY, J. Challenges in speech processing of Slavic languages (case studies in speech recognition of Czech and Slovak). Lecture Notes in Computer Science, 2010, vol. 5967/2010, p. 225 - 241.
- POLLAK, P., CERNOCKY, J. Czech SPEECON Adult Database (technical report). 2004.

Keywords: speech recognition, LVCSR, n-gram language models, public language resources

**L. Krasula, M. Klima, E. Rogard, E. Jeanblanc**
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MATLAB-Based Applications for Image Processing and Image Quality Assessment – Part I: Software Description

This paper describes several MATLAB-based applications useful for image processing and image quality assessment. The Image Processing Application helps user to easily modify images, the Image Quality Adjustment Application enables to create series of pictures with different quality. The Image Quality Assessment Application contains objective full reference quality metrics that can be used for image quality assessment. The Image Quality Evaluation Applications represent an easy way to compare subjectively the quality of distorted images with reference image. Results of these subjective tests can be processed by using the Results Processing Application. All applications provide Graphical User Interface (GUI) for the intuitive usage.

- BREMOND, R., TAREL, J.-P., DUMONT, E., HAUTIERE, N. Vision models for image quality assessment: One is not enough. Journal of Electronic Imaging, vol. 19(4), 000000 October – December 2010.
- SHEIKH, H. R., BOVIK, A. C., VECIANA, G. D. An information fidelity criterion for image quality assessment using natural scene statistics. IEEE Transactions on Image Processing, vol. 14, no. 12, p. 2117-2128, December 2005.
- SHEIKH, H. R., BOVIK, A. C. Image information and visual quality. IEEE Transaction on Image Processing, vol. 15, no. 2, February 2006. [Online]. Available at: http://live.ece.utexas.edu/ research/Quality/index.htm
- MeTriX MuX Visual Quality Assessment Package. [Online]. Available at: http://foulard.ece.cornell.edu/gaubatz/metrix_mux/
- SPRLJAN, N. MATLAB Quality Assessment Toolbox. [Online]. Available at: http://www.sprljan.com/nikola/matlab.html
- MURTHY, A. V., KARAM, L. J. A MATLAB-Based Framework for Image and Video Quality Evaluation. QoMEX, 2010.
- ROGARD, E. Image Quality Assessment: The implementation of metrics by analysis with Matlab. CTU report, September 2007.
- ROGARD, E. User guide of the Image Processing Toolbox. CTU report, June – September 2007.
- JEANBLANC, E. User guide of MATLAB Toolboxes. CTU report, June – September 2009.
- WANG, Z., BOVIK, A. C., SHEIKH, H. R., SIMONCELLI, E. P. Image quality assessment: From error visibility to structural similarity. IEEE Transactions on Image Processing, vol. 13, no. 4, p. 600-612, April 2004. [Online]. Available at: http://www.ece.uwaterloo.ca/~z70wang/research/ssim/
- WANG, Z., BOVIK, A. C. A Universal Image Quality Index. IEEE Signal Processing Letters, March 2002, vol. 9, no. 3, p. 81- 84. [Online]. Available at: http://www.cns.nyu.edu/ ~zwang/files/research/quality_index/demo.html

Keywords: Image quality evaluation, Image processing, Quality metrics, QoE

**M. Klima, K. Fliegel, P. Pata, S. Vitek, M. Blazek, P. Dostal, L. Krasula, T. Kratochvil, V. Ricny, M. Slanina, L. Polak**
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DEIMOS – an Open Source Image Database

The DEIMOS (DatabasE of Images: Open Source) is created as an open-source database of images and videos for testing, verification and comparing of various image and/or video processing techniques such as enhancing, compression and reconstruction. The main advantage of DEIMOS is its orientation to various application fields – multimedia, television, security, assistive technology, biomedicine, astronomy etc. The DEIMOS is/will be created gradually step-by-step based upon the contributions of team members. The paper is describing basic parameters of DEIMOS database including application examples.

- DEIMOS – Database of Images: Open Source. http://www.deimosproject. cz/, CTU FEE Prague & FEEC BUT Brno, 2010.
- FISHER, W. Digital Video and Audio Broadcasting. A Practical Engineering Guide. 2nd ed. Springer, 2008. ISBN 978-3-540- 76357-4.
- REIMERS, U. Digital Video Broadcasting, The Family of International Standards for Digital Television. 2nd ed. Springer, 2004. ISBN 3-540-43545-X
- KRATOCHVIL, T.; SLANINA, M. Digital video image quality. In Digital Video. Edited by: Floriano De Rango, Chapter 23: Digital Video Image Quality. INTECH. Vienna, Austria: INTECH Excellence in Education and Publishing, 2010, p. 487–500. ISBN: 978-953-7619-70-1.
- SLANINA, M., KRATOCHVIL, T., POLAK, L., RICNY, V. Temporal aspects of scoring in the user based quality evaluation of HD video. In Proceedings of the TSP 2011 conference (in print).
- HIRAKAWA, K., PARKS, T. W., Adaptive homogeneity-directed demosaicing algorithm. IEEE Transaction on Image Processing, 2005, vol. 14, no. 3, p. 360–368.
- MENON, D., ANDRIANI, S., CALVAGNO, G. Demosaicing with directional filtering and a posteriori decision. IEEE Transactions on Image Processing, 2007, vol. 16, no. 1, p. 132–141.
- ALLEYSSON, D., SUSSTRUNK, S., HERAULT, J. Linear demosaicing inspired by human visual system, IEEE Transactions on Image Processing, April 2005, vol. 14, no. 4,p. 439–449.
- CHUNG, K. L., et al. Demosaicing of color filter array captured images using gradient edge detection masks and adaptive heterogeneity-projection. IEEE Transaction on Image Processing, December 2008, vol. 17, no. 12, p. 2356–2367.
- BAYER, B. E. Color Imaging Array. U.S. Patent 3 971 065, 1976
- JIANG. G., et al. Stereoscopic visual attention-based regional bit allocation optimization for multiview video coding. Eurasip Journal on Advances in Signal Processing, 2010.
- DOSTAL, P., KLIMA, M. Locally adaptive demosaicing technique for security images based upon Region-of-Interest Analysis. In IEEE International Carnahan Conference on Security Technology. Piscataway, Barcelona, October 2011 (in print).
- Ambient Assisted Living Joint Programme. (AAl). [online] Available at: http://www.aal-europe.eu/
- Health-EU. The Public Health Portal of the European Union. [online] Available at: http://ec.europa.eu/health-eu/care_for_me/ehealth/ index_en.htm
- BOOTES, Burst Observer and Optical Transient Exploring System. [online] Available at: http://www.laeff.esa.es/BOOTES /ing/index.html, 2011.
- KOTEN, P., FLIEGEL, K., VITEK, S., PATA, P. Automatic video system for continues monitoring of the meteor activity. Earth, Moon, and Planets. 2011, vol. 108, no. 1, p. 69-76.
- FLIEGEL, K., HAVLIN, J. Imaging photometer with a nonprofessional digital camera. In Proc. SPIE 7443, 2009.
- FLIEGEL, K. Modeling and measurement of image sensors characteristics. Radioengineering, 2004, vol. 13, no. 4, p. 27-34.
- ISO Geneva. Photography – Electronic still-picture cameras – Methods for measuring opto-electronic conversion functions (OECFs), International Organization for Standardization, 1999.
- REINHARD, E., WARD, G., PATTANAIK, S., DEBEVEC, P. High Dynamic Range Imaging: Acquisition, Display, and Image- Based Lighting. Amsterdam: Elsevier, 2006.
- FAIRCHILD, M. D. The HDR photographic survey, In Proceedings of the 15th Color Imaging Conference, p. 233-238, 2009.
- NIKON. Product documentation, http://imaging.nikon.com/.
- BENOIT, A., LE CALLET, P., CAMPISI, P., COUSSEAU, R. Using disparity for quality assessment of stereoscopic images. In Proc. IEEE ICIP, 2008, p. 389-392.
- GOLDMANN, L., DE SIMONE, F., EBRAHIMI, T. A comprehensive database and subjective evaluation methodology for quality of experience in stereoscopic video. In Proc. SPIE 7526, 2010.
- FLIEGEL, K., VITEK, S., KLIMA, M., PATA, P. Open source database of images DEIMOS: high dynamic range and stereoscopic content. In Proc. SPIE 8135, 2011.
- JAVIDI, B., OKANO, F. Three-Dimensional Television, Video, and Display Technologies. Springer, 2002.

Keywords: Database, image, video, multimedia, television, security, assistive technology, CCTV, optical systems, astronomy, 3D TV, stereoscopic applications

**D. Bonefacić**
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Guest Editorial: Special Issue on Applied Electromagnetics and Communications

**P.J Soh, G.A.E Vandenbosch, S.L Ooi, H.M.R Nurul**
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Characterization of a Plain Broadband Textile PIFA

Bandwidth characteristic of a wearable antenna is one of the major factors in determining its usability on the human body. In this work, a planar inverted-F antenna (PIFA) structure is proposed to achieve a large bandwidth to avoid serious antenna reflection coefficient detuning when placed in proximity of the body. The proposed structure is designed based on a simple structure, in order to provide practicality in application and maintain fabrication simplicity. Two different types of conductive textiles, namely Pure Copper Polyester Taffeta Fabric (PCPTF) and ShieldIt, are used in order to proof its concept, in comparison with a metallic antenna made from copper foil. The design is spaced and fabricated using a 6 mm thick fleece fabric. To cater for potential fabrication and material measurement inaccuracies, both antennas' performance are also investigated and analyzed with varying physical and material parameters. From this investigation, it is found that the proposed structure's extended bandwidth enabled the antenna to function with satisfactory on-body reflection coefficients, despite unavoidable gain and efficiency reduction.

- SOH, P.J., VANDENBOSCH, G.A.E., OOI, S.L., NURUL, H.M.R. Characterization of a simple broadband textile planar inverted-F antenna (PIFA) for on body communications. In Proceedings of the 20th International Conference on Applied Electromagnetics and Communication, ICECom. Dubrovnik (Croatia), 2010, p. 1 - 4.
- EBRAHIMI-GANJEH, M.A., ATTARI, A.R. Interaction of dual band helical and PIFA handset antennas with human head and hand. Progress in Electromagnetic Research, 2007, vol. 77, p. 225 - 242.
- DECLERCQ, F., ROGIER, H., Characterization of electromagnetic properties of textile materials for the use in wearable antennas. In Proceedings of the IEEE Antennas and Propagation Society International Symposium, APURSI. USA, 2009, p. 1 - 4.
- SALONEN, P., YANG, F., RAHMAT-SAMII, Y., KIVIKOSKI, M. WEBGA - Wearable Electromagnetic Band-gap Antenna. In Proceedings of the IEEE Antennas and Propagation Society International Symposium. USA, 2004, vol. 1, p. 451 - 454.
- CONWAY, G.A., SCANLON, W.G. Antennas for over-bodysurface communication at 2.45 GHz. IEEE Transactions on Antennas and Propagation, 2009, vol. 57, no. 4. p. 844 - 855.
- SALONEN, P., HURME, L. A novel fabric WLAN antenna for wearable applications. In Proceedings of IEEE Antennas and Propagation Society International Symposium. USA, 2003, vol. 2, p. 700 - 703.
- SAIDATUL, N.A., AZREMI, A.A.H., AHMAD, R.B., SOH, P.J., MALEK, F. Multiband fractal planar inverted-F antenna (F-PIFA) for mobile phone application. Progress in Electromagnetic Research B, 2009, vol. 14, p. 127 - 148.
- SOH, P.J., VANDENBOSCH, G.A.E., OOI, S.L., NURUL, H.M.R. Design of a broadband all-textile slotted PIFA. IEEE Transactions on Antennas and Propagation, accepted, in press.
- SOH, P.J., VANDENBOSCH, G.A.E., OOI, S.L., HUSNA, M.R.N. Wearable dual-band Sierpinski fractal PIFA using conductive fabric. Electronics Letters, 2011, vol. 47, no. 6. p. 365 - 367.
- HERTLEER, C., ROGIER, H., VALLOZZI, L., VAN LANGENHOVE, L. A textile antenna for off-body communication integrated into protective clothing for firefighters. IEEE Transactions on Antennas and Propagation, 2009, vol. 57, no. 4, p. 919 - 925.
- HERTLEER, C., TRONQUO, A., ROGIER, H., VALLOZZI, L., VAN LANGENHOVE, L. Aperture-coupled patch antenna for integration into wearable textile systems. IEEE Antennas and Wireless Propagation Letters, 2007, vol. 6, p. 392 - 395.
- WWW.LESSEMF.COM. Product Datasheet, ShieldIt Super, Pure Copper Polyester Taffeta Fabric. Albany, NY, USA. Nov 2011.
- WONG, K.L. Planar Antennas for Wireless Communications. Wiley-Interscience, 2003.
- CHATTA, H.T., HUANG, YI., XU, Z., YANG, L. An empirical equation for predicting the resonant frequency of planar inverted-F antennas. IEEE Antennas and Wireless Propagation Letters, 2009, vol. 8, p. 856 - 860.
- KHATTAK, M.I., EDWARDS, R.M., MA, J. A study of perturbations due to antennas in close proximity with the human body and body simulating liquid filled phantoms at 1.8 GHz. In Proceedings of the Loughborough Antennas and Propagation Conference, LAPC. Loughborough (UK), 2009, p. 625 - 628.

Keywords: Textile antennas, conformal antennas, broadband antennas, planar inverted-F antenna (PIFA), on-body communication.

**I. Dioum, M. Clemente, A. Diallo, C. Luxey, J. P. Rossi, S. M. Farssi**
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Meandered Monopoles for 700 MHz LTE Handsets and Improved MIMO Channel Capacity Performance

In this paper, we present the design and the measurement of MIMO meandered monopole antennas and the computation of their channel capacity performance. The initial proposed handset-system is composed of a meandered monopole operating in the LTE 700 MHz band, connected to a parasitic radiating element for the upper 2.5 GHz LTE band. Two antennas of the same kind are then closely positioned on the same 120x50 mm2 Printed Circuit Board (PCB). A neutralization line connects the two antennas to enhance their port-to-port isolation in the 700 MHz band. The computation of the channel capacity performance in this band is based on propagation simulations performed with the GRIMM model from the CREMANT. Two system-prototypes are evaluated: one with the neutralization line for enhanced port-to-port isolation and a second without the neutralization exhibiting poor antenna-to-antenna isolation. It is demonstrated that the neutralization technique helps in giving a minimum improvement of 12% of the capacity performance of the handset-system, and a maximum improvement 46%, in the chosen environment.

- DIALLO, A., LUXEY, C., LE THUC, P., STARAJ, R., KOSSIAVAS, G. Enhanced diversity antennas for UMTS RADIOENGINEERING, VOL. 20, NO. 4, DECEMBER 2011 731 handsets. In Proceedings of the European Conf. on Antennas and Propagations (EuCAP06). Nice (France), Nov. 2006.
- YU, Y., KIM, G., SEONG, W., CHOI, J. A MIMO antenna with a two stage ground for USB dongle. Microwave and Optical Technology Letters, Feb. 2011, vol. 53, no. 2, p. 418 - 422.
- BHATTI, R.A., YI, S., PARK, S. Compact antenna array with port decoupling for LTE-Standardized Mobile Phones. IEEE Antennas and Wireless Propagation Letters, 2009, vol. 8, p. 1430-1433.
- TORNATTA, P. Overcoming the LTE handset antenna design problem. EE Times-Asia, http://www.eetasia.com/STATIC/PDF/ 200908/EEOL_2009AUG13_RFD_TA_01.pdf?SOURCES=DOW NLOAD, 13th August 2009.
- LUXEY, C. Design of multi-antenna systems for UMTS mobile phones. In Proceedings of the Loughborough Antennas & Propagation Conference, 2009. Loughborough (UK), Nov. 2009.
- LUXEY, C., MANTEUFFEL, D. Highly-efficient multiple antennas for MIMO-systems. In IEEE International Workshop on Antenna Technology, 2010. Lisbon (Portugal), 1-3 March 2010.
- DIALLO, A., LUXEY, C., LE THUC, P., STARAJ, R., KOSSIAVAS, G. Study and reduction of the mutual coupling between two mobile phone PIFAs operating in the DCS1800 and UMTS bands. IEEE Transactions on Antennas and Propagation, November 2006, Part.1, vol. 54, no. 11,p. 3063-3074.
- DIALLO, A., LUXEY, C., LE THUC, P., STARA,J R., KOSSIAVAS, G. An efficient two-port antenna-system for GSM/DCS/UMTS multi-mode mobile phones. Electronics. Letters, March 2007, vol. 43, no. 7, p. 369-370.
- DIALLO, A., LUXEY, C., LE THUC, P., STARAJ, R., KOSSIAVAS, G. Diversity performance of multi-antenna systems for UMTS cellular phones in different propagation environments. International Journal on Antennas and Propagation (IJAP), 2008, Article ID 836050, 10 pages. doi:10.1155/2008/836050, http://www.hindawi.com/GetArticle.aspx?doi=10.1155/2008/8360 50. 2008
- CHEBIHI, A., LUXEY, C., DIALLO, A., LE THUC, P., STARAJ, R. A novel isolation technique for closely spaced PIFAs for UMTS mobile phones. IEEE Antennas and Wireless Propagation Letters, 2008, vol. 7, p. 665-668.
- DIALLO, A., LUXEY, C., LE THUC, P., STARAJ, R., KOSSIAVAS, G., FRANZEN, M., KILDAL, P.-S. Diversity characterization of optimized two-antenna systems for UMTS handsets. EURASIP Journal on Wireless Communications and Networking, vol. 2007, Article ID 37574, 9 pages, doi:10.1155/2007/37574, http://www.hindawi.com/GetArticle.- aspx?doi=10.1155/2007/37574.
- DIALLO, A., LUXEY, C., LE THUC, P., STARAJ, R., KOSSIAVAS, G. Enhanced two-antenna structures for universal mobile telecommunications system diversity terminals. IET Microwaves, Antennas and Propagation, Feb. 2008, vol. 2, no. 1, p. 93-101.
- CIAIS, P., LUXEY, C., DIALLO, A., STARAJ, R., KOSSIAVAS, G. Pentaband internal antenna for handset communication devices. Microwave and Optical Technology Letters, August 2006, vol. 48, no. 8, p. 1509-1512.
- DIOUM, I., DIALLO, A., LUXEY, C., FARSI, S. M. Dual band monopole MIMO antennas for LTE mobile phones. In 20th International Conference on Applied Electromagnetics and Communications (ICECom 2010). Dubrovnik (Croatia), 20–23 September 2010.
- DIOUM, I., DIALLO, A., LUXEY, C., FARSI, S. M. Compact dual-band monopole antenna for LTE mobile phones. In Loughborough Antennas & Prop. Conf. (LAPC 2010). Loughborough (UK), 14-15 November 2010.
- DIALLO, A., LUXEY, C., LE THUC, P., STARAJ, R., KOSSIAVAS, G., FRANZEN, M., KILDAL, P.-S. MIMO performance of enhanced UMTS four-antenna structures for mobile phones in the presence of the user’s head. In IEEE Antennas and Propagation Society International Symposium (APS 2007). Honolulu (HI, USA), 10-17 June 2007.
- RANVIER, S., LUXEY, C., SUVIKUNNAS, P., STARAJ, R., VAINIKAINEN, P. Capacity enhancement by increasing both mutual coupling and efficiency: a novel approach. In IEEE Antennas and Propagation Society International Symposium (APS 2007), Honolulu (HI, USA), 10-17 June 2007.
- FOSCHINI, G. J., GANS, M. On the limits of wireless communications in a fading environment when using multiple antennas. Wireless Personal Comm., 1998, vol. 6, p. 311-335.
- SALO, J., BADIC, B., SUVIKUNNAS, P., WEINRICHTER, H., RUPP, M., VAINIKAINEN, P. Influence of antenna configurations on performance of STBC in urban microcells. IET Electronics Letters, October 2005, vol. 41, no. 21, p. 1157-1158.
- VERGERIO, S., ROSSI, J-P., CHAUFRAY, J-M. MIMO capacity simulation in cellular environment with a ray model. In ETTC 05 European Test and Telemetry Conf. Toulouse (France), June 2005.
- ROSSI, J. P., GABILLET, Y. A mixed ray launching/tracing method for full 3-D UHF propagation modelling and comparison with wide-band measurements. IEEE Transactions on Antennas and Propagation, April 2002, vol. 50, no. 4, p. 517-523.
- ROSSI, J-P., VERGERIO, S., CONRAT, J-M., PAJUSCO, P., SABOUROUX, P. Physical model reliability for the prediction of MIMO channel capacity. Submitted to IEEE Transactions on Antennas and Propagations.
- BECKMANN, P., SPIZZICHINO, A. The Scattering of Electromagnetic Waves from Rough Surfaces. Artech House, 1987.

Keywords: MIMO communications, Channel capacity, Mobile communications, LTE Bands, Monopole antennas.

**L. Dussopt, H. Kaouach, J. Lanteri, R. Sauleau**
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Circularly-Polarized Discrete Lens Antennas in the 60-GHz Band

This paper presents the design and demonstration of two circularly-polarized transmit-arrays operating in the 60-GHz band and generating a broadside beam and a 30°-tilted beam respectively. These arrays have a fairly simple structure with only three metal layers and are fabricated with a standard printed-circuit board technology. The simulated results show the performances of the unit-cells as well as the whole arrays, and detail their power budget. The experimental results in V-band are in very good agreement with the simulations and demonstrate very satisfactory characteristics. Power efficiencies up to 53.7% are reached with a 1-dB gain-bandwidth up to 9.1%, and low cross-polarization level.

- SCHWARTZMAN, L., TOPPER, L. Analysis of phased array lenses. IEEE Transactions on Antennas and Propagation, June 1968, vol. 16, no. 6, p. 628 – 632.
- MCGRATH, D. T. Planar three-dimensional constrained lenses. IEEE Transactions on Antennas and Propagation, June 1986, vol. 34, no. 6, p. 46 – 50.
- POZAR, D. M. Flat lens antenna concept using aperture coupled microstrip patches. Electronics Letters, 7th Nov. 1996, vol. 32, no. 23, p. 2109 – 2111.
- PADILLA DE LA TORRE, P., SIERRA-CASTANER, M., SIERRA-PEREZ, M. Design of a double array lens. In Proceedings of the 1st European Conference on Antennas and Propagation. Nice (France), 6-10 Nov. 2006.
- ABBASPOUR-TAMIJANI, A., SARABANDI, K., REBEIZ, G.M. A millimeter-wave bandpass filter-lens array. IET Microwaves, Antennas and Propagation, Feb. 2007, vol. 1, no. 2, p. 388 – 395.
- RYAN, C.G.M., CHAHAMIR, M.R., SHAKER, J., BRAY, J.R., ANTAR, Y.M.M. ITTIPIBOON, A. A wideband transmitarray using dual-resonant double square rings. IEEE Transactions on Antennas and Propagation, May 2005, vol. 58, no. 5, p. 1486 – 1493.
- XIAO, S.Q., ZHOU, M.T., ZHANG, Y. Millimeter Wave Technology in Wireless PAN, LAN, and MAN. CRC Press, 2008.
- FCC, “Millimeter wave 70-80-90 GHz service”, [Online]. Available at: http://wireless.fcc.gov/services/ index.htm? job=service_home.
- KAOUACH, H., DUSSOPT, L., LANTERI, J., KOLECK, T., SAULEAU, R. Circularly-polarized discrete lens antennas in the 60-GHz band. In Proceedings of the 20th International Conference on Applied Electromagnetics and Communications. Dubrovnik (Croatia), 20-23 Sept. 2010.
- KAOUACH, H., DUSSOPT, L., LANTERI, J., KOLECK, T., SAULEAU, R. Wideband low-loss linear and circular polarization transmit-arrays in V-band. IEEE Transactions on Antennas and Propagation, July 2011, vol. 59, no. 7, p. 2513 – 2523.
- KAOUACH, H., DUSSOPT, L., SAULEAU, R., KOLECK, T. Design and demonstration of 1-bit and 2-bit transmit-arrays at Xband frequencies. In Proceedings of the 39th European Microwave Conference. Roma (Italy), 29 Sept.-1 Oct. 2009.
- KAOUACH, H., DUSSOPT, L., SAULEAU, R., KOLECK, T. X-band transmit-arrays with linear and circular polarization. In Proceedings of the 4th European Conference on Antennas and Propagation. Barcelona (Spain), 12-16 April 2010.

Keywords: Discrete lens, transmit-array, unit-cell, millimeter-wave antennas, 60 GHz band

**F. De Vita, P. De Vita, A. Freni**
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Efficient Analysis for the Design Refinement of Large Multilayered Printed Reflectarrays

In this paper, we present an efficient numerical technique for the analysis of a reflectarray and its design refinement by the characterization of the “actual” influence of each radiating element when embedded in the antenna structure. The method makes use of the MLayAIM, a fast full-wave formulation suitable for the analysis of electrically large multilayered printed arrays which have one or more planar metallizations and vertical conductors. The low numerical complexity of the analysis method allows the development of a recursive procedure that, starting from the equivalent currents relevant to each cell of the reflectarray when this is immersed in the actual antenna layout, calculates the real phase-shift introduced by each radiating element and corrects its dimensions to better fit the antenna requirements.

- HUANG, J., ENCINAR, J. A. Reflectarray Antennas. IEEE Press, John Wiley, 2008.
- POZAR, D. M., TARGONSKI, S. D., POKULS, R. A shapedbeam microstrip patch reflectarray. IEEE Trans. Antennas Propagat, 1999, vol. 47, no. 7, p. 1167-1173.
- POZAR, D. M., TARGONSKI, S. D., SYRIGOS, H. D. Design of millimeter wave microstrip reflectarrays. IEEE Trans. Antennas Propagat., 1997, vol. AP–45, no. 2, p. 287–296.
- ENCINAR, J. A., DATASHVILI, L. SH., ZORNOZA, J. A., ARREBOLA, M., SIERRA-CASTANER, M., BESADA- SANMARTIN, J. L., BAIER, H., LEGAY, H. Dual-polarization dual-coverage reflectarray for space applications. IEEE Trans. Antennas Propag., 2006, vol. 54, no. 10, p. 2827–2837.
- DE VITA, P., DE VITA, F., DI MARIA, A., FRENI, A. An efficient technique for the analysis of large multilayered printed arrays. IEEE Antennas and Wireless Propagation Letters, 2009, vol. 8, p. 104–107.
- BLESZYNSKI, E., BLESZYNSKI, M., JAROSZEWICZ, T., AIM: Adaptive integral method for solving large–scale electromagnetic scattering and radiation problems, Radio Science, 1996, vol. 5, pp. 1225–1251.
- MOSIG, J. R. Arbitrarily shaped microstrip structures and their analysis with a mixed potential integral equation. IEEE Trans. Microwave Theory Tech., Feb. 1988, vol. 36, no. 2, p. 314–323.
- RAO, S. M., WILTON, D. R., GLISSON, A. W. Electromagnetic scattering by surfaces of arbitrary shape. IEEE Trans. Antennas Propag., 1982, vol. 30, p. 409–418.
- MICHALSKI, K. A., MOSIG, J. R. Multilayered media Green’s functions in integral equation formulations. IEEE Trans. Antennas and Propagat., 1997, vol. AP–45, p. 508–519.
- DE VITA, P., FRENI, A., DASSANO, G. L., PIRINOLI, P., ZICH, R. E. Broadband element for high-gain single-layer printed reflectarray antenna. Electronics Letters, 2007, vol. 43, n. 23, p. 1247–1249.

Keywords: Reflectarrays, Method of Moments, Adaptive Integral Method.

**C. Pfeffer, S. Scheiblhofer, R. Feger, A. Stelzer**
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An S-FSCW Based Multi-Channel Reader System for Beamforming Applications using Surface Acoustic Wave Sensors

Interrogating multiple surface acoustic wave (SAW) sensors located within the same radar beam require techniques to separate the multiple superposing SAW sensor responses. The presented multi-channel reader features four parallel transceiver channels, which are based on the switched frequency-stepped continuous-wave principle and high-speed parallelized baseband electronics. Thus classical beamforming applications including angle of arrival measurement of single SAW tags and the angular separation of multiple SAW sensors are presented and compared to a multiple-input multiple-output (MIMO) approach. Due to the larger virtual array in the MIMO approach a larger aperture can be synthesized, which leads to significantly better angular separation results. The level analysis for the given system is verified by baseband-power measurements at different readout distances, considering the hardware parameters as well as the free-space propagation aspects. Finally measurements assess the maximum interrogation distance for the system.

- KALININ, V. Passive wireless strain and temperature sensors based on SAW devices. In Proceedings of the IEEE Radio and Wireless Conference. Atlanta (USA), September 2004, p. 187 - 190.
- HARTMAN, C. A global SAW ID tag with large data capacity. In Proceedings of the IEEE Ultrason. Symp. Munich (Germany), October 2002, p. 65 - 69.
- POHL, A. A review of wireless SAW sensors. IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, March 2000, vol. 47, no. 2, p. 317 - 332.
- STELZER, A., SCHEIBLHOFER, S., SCHUSTER, S., BRANDL, M. Multi reader/multi tag SAW RFID systems combining tagging, sensing and ranging for industrial applications. In Proceedings of the International Frequency Control Symposium. Honolulu (USA), May 2008, p. 263 – 272.
- SCHEIBLHOFER, S., PFEFFER, C., FEGER, R., STELZER, A. An S-FSCW based multi-channel reader system for beamforming applications using surface acoustic wave sensors. In Proceedings of the Conference ICECom 2010. Dubrovnik (Croatia), September 20-23, 2010, p. 1 - 4.
- SCHEIBLHOFER, S., SCHUSTER, S., STELZER, A. Modelling and performance analysis of SAW reader systems for delay-line sensors. IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, October 2009, vol. 56, no. 10, p. 2293 - 2303.
- SCHEIBLHOFER, S., SCHUSTER, S., STELZER, A., HAUSER, R. S-FSCW-radar based high resolution temperature measurement with SAW sensors. In Proceedings of the 6th International Symposium on Signals, Systems, and Electronics (ISSSE’04). Linz (Austria), August 10-13, 2004, p. 128 - 131.
- BALANIS, C. A., Antenna Theory: Analysis and Design. 3rd ed. Hoboken, NJ: Wiley, 2005.
- FEGER, R., WAGNER, C., SCHUSTER, S., SCHEIBLHOFER, S., STELZER, A. Accuracy improvement for direction of arrival Microwave Theory and Techniques, April 2011, vol. 59, no. 4, p. 1016 - 1024.
- FEGER, R., WAGNER, C., SCHUSTER, S., SCHEIBLHOFER, S., JAGER, H., STELZER, A. A 77-GHz FMCW MIMO radar based on a SiGe single-chip transceiver. IEEE Transactions on Microwave Theory and Techniques, May 2009, vol. 57, no. 5, p. 1020 - 1035.
- TREES, H. L. Detection, Estimation, and Modulation Theory, Part IV, Optimum Array Processing. New York, NY: Wiley Interscience, 2002.

Keywords: S-FSCW, SAW-tag, Multi-Cannel Reader System, Beamforming, MIMO, AOA

**G. A. E. Vandenbosch, A. Vasylchenko, M. Fernandez-Bolanos, S. Brebels, W. De Raedt, A. M. Ionescu**
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Miniature Sensor Node with Conformal Phased Array

This paper reports on the design and fabrication of a fully integrated antenna beam steering concept for wireless sensor nodes. The conformal array circumcises four cube faces with a silicon core mounted on each face. Every silicon core represents a 2 by 1 antenna array with an antenna element consisting of a dipole antenna, a balun, and a distributed MEMS phase shifter. All these components are based on a single wafer process and designed to work at 17.2 GHz. Simulations of the entire system and first results of individual devices are reported.

- AERTS, W., DELMOTTE, P., VANDENBOSCH, G. A. E. Conceptual study of analog baseband beam forming: design and measurement of and eight-by-eight phased array. IEEE Trans. Antennas Propagat., June 2009, vol. 57, no. 6, p. 1667-1672.
- SOLIMAN, E. A., BREBELS, S., BEYNE, E., VANDENBOSCH, G. A. E. Circularly polarized aperture antenna fed by CPW and built in MCM-D technology. Electron. Lett., Feb. 1999, vol. 35, no. 4, pp. 250-251.
- SOLIMAN, E. A., BREBELS, S., BEYNE, E., VANDENBOSCH, G. A. E. CPW fed cusp antenna. Microwave and Opt. Techn. Lett., Aug. 1999, vol. 22, no. 4, p. 288-290.
- VAN CAEKENBERGHE, K. RF MEMS on the Radar. IEEE Microwave Mag., October 2009, vol. 10, p. 99-116.
- CETINER, B. A., QIAN, J. Y., CHANG, H. P., BACHMAN, M., LI, G. P., DE FLAVIIS, F. Monolithic integration of RF MEMS switches with a diversity antenna on PCB substrate. IEEE Trans. Microw. Theory Tech., January 2003, vol. 51, no. 1, p. 332-335.
- CHENG, S., RANTAKARI, P., MALMQVIST, R., SAMUELSSON, C., VAHA-HEIKKILA, T., RYDBERG, A., VARIS, J. Switched beam antenna based on RF MEMS SPDT switch on quartz substrate. IEEE Antennas Wireless Propag. Lett., 2009, vol. 8, p. 383-386.
- TOPALLI, K., CIVI, O. A., DEMIR, S., KOC, S., AKIN, T. A monolithic phased array using 3-bit distributed RF MEMS phase shifters. IEEE Trans. Microw. Theory Tech., February 2008, vol. 56, no. 2, p. 270-277.
- BAEK, C.-W., SONG, S., PARK, J.-H., LEE, S., KIM, J.-M., CHOI, W., CHEON, C., KIM, Y.-K., KWON, Y. A V-band micromachined 2-D beam-steering antenna driven be magnetic force with polymer-based hinges. IEEE Trans. Microw. Theory Tech., January 2003, vol. 51, no. 1, p. 325-331.
- ENAYATI, A., BREBELS, S., DE RAEDT, W., VANDENBOSCH, G. A. E. 3D-antenna-in-package solution for microwave wireless sensor network nodes. IEEE Trans. Antennas Propagat., Oct. 2011, vol. 59, no. 10, p. 3617-3623.
- FERNANDEZ-BOLAÑOS, M., VASYLCHENKO, A., DAINESI, P., BREBELS, S., DE RAEDT, W., VANDENBOSCH, G. A. E., IONESCU, A. M. Dipole antenna and distributed MEMS phase shifter fully integrated in a single wafer process for beam steering applications. Microelectron. Eng., Feb. 2010, vol. 87, p. 1290- 1293.
- FERNANDEZ-BOLAÑOS, M., PERRUISSEAU-CARRIER, J., DAINESI, P., IONESCU, A. M. RF MEMS capacitive switch on semi-suspended CPW using low-loss high-resistivity silicon substrate. Microelec. Eng., June 2007, vol. 85, p. 1039-1042.

Keywords: Conformal array, sensor node, miniaturization

**A.Dikovic, G.Sisul, B.Modlic**
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A Low Cost Platform for Sensor Network Applications and Educational Purposes

In this paper we describe the design, key features and results obtained from the development of a generic platform usable for sensor network applications operational in the ISM band. The goal was to create an open source low cost platform suitable for use in educational environment. The platform should allow students to easily grasp the fundamentals of wireless sensor networks so special attention was paid to basic concepts related to their functioning. Two versions of this platform were designed, the first one being a proof of concept and the second one more adequate to field test and measurements. Practical aspects of implementation such as network protocol, power consumption, processing speed, media access are discussed.

- AKYILDIZ, I.F., SU, W., SANKARASUBRAMANIAM, Y., CAYIRCI, E. A survey on sensor networks. IEEE Comm. Magazine, Aug. 2002, vol. 40, no. 8, p. 102-114.
- EL-HOIYDI, Y A., ARM, C., CASEIRO, R., CSERVENY, S., DECOTIGNIE, J.-D., ENZ, C., GIROUD, F., GYGER, S., LEROUX, E., MELLY, T., PEIRIS, V., PENGG, F., PFISTER, P.- D., RAEMY, N., RIBORDY, A., RUFFIEUX, D., VOLET, P. The ultra low-power WiseNET system. IEEE Proceedings of the Design Automation & Test in Europe. Conference DATE 2006, vol. 1, p.206.
- CALLAWAY, E. H. Wireless Sensor Networks: Architectures and Protocols. Auerbach publications, Boca Raton, 2004.
- JURDAK, R., RUZZELLI, A. G., O'HARE, G.M.P. Radio sleep mode optimization in wireless sensor networks. IEEE Transactions on Mobile Computing, July 2010, vol. 9, no. 7.
- FARAHANI, S. ZigBee Wireless Networks and Transceivers. Elsevier Ltd., Burlington, 2008.
- ATMEL CORPORATION, ATtiny2313 datasheet, available at htt p://www.atmel.com/dyn/resources/prod_documents/doc2543.pdf
- HOPERF ELECTRONIC, RFM22 Datasheet, available at http://www.hoperf.com/upload/rf/RFM22.PDF
- KUORILEHTO, M., KOHVAKKA, M., SUHONEN, J., HAMALAINEN, P., HANNIKAINEN, M., HAMALAINEN, T.D. Ultra-Low Energy Wireless Sensor Networks in Practice - Theory, Realization and Deployment. Chichester: Wiley, 2007.
- HILL, J.L., CULLER, D.E. Mica: A wireless platform for deeply embedded networks. IEEE Micro, Nov/Dec 2002, vol. 22, no. 6, p. 12-24.
- COHN, G., STUNTEBECK, E.P., PANDEY, J., OTIS, B., ABOWD, G.D., PATEl, S.N. SNUPI: Sensor nodes utilizing powerline infrastructure. In Proceedings of UbiComp2010. The ACM International Conference on Ubiquitous Computing, Copenhagen (Denmark), 2010, p.159-168.

Keywords: Sensor network, media access control, microcontroller, GFSK, Si4432, low power, star topology, battery power

**W. J. Krzysztofik, R. Borowiec, B. Bieda**
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Some Consideration on Shielding Effectiveness Testing by means of the Nested Reverberation Chambers

This paper evaluates the effects of test fixture isolation when using nested mode-stir chambers for conducting electromagnetic shielding measurements. The nested chamber technique is used by both government and industry to evaluate the electromagnetic attenuating properties of materials as varied as infrared sensor windows to the composites used in the hulls of new ships, EM-protection of human as well as devices. Numerical simulation by means of CST and FEKO software of different nested chambers arrangements were done. Some preliminary test measurements of designed and manufactured the small reverberation chamber were done and compare with the numerical simulation results.

- International Electrotechnical Commission, Testing and Measurement Technique-Reverberation Chamber Test Methods, Standard 6100-4-21, 2003.
- HOLLOWAY, C.L., HILL, D.A., LADBURY, J., G., KOEPKE, R. GARZIA, Shielding effectiveness measurements of materials using nested reverberation chambers. IEEE Trans. Electromagn. Compat., May 2003, vol. 45, no. 2, p. 350-356.
- American Society for Testing and Materials, Standard Test Method for Measuring the Electromagnetics Sheilding Effectiveness of Planar Materials. Standard D4935-99, 1999.
- CATRYSSE, J., DELESIE, M., STEENBAKKERS, W. The influence of the test fixture on shielding effectiveness measurements. IEEE Trans. Electromagn. Compat., Aug. 1992, vol. 34, no. 3, p. 348-351.
- SARTO, M.S., TAMBURRANO, A. Innovative test method for shielding effectiveness measurement of conductive thin film in a wide frequency range. IEEE Trans. Electromagn. Compat., May 2006, vol. 48, no. 2, p. 331-341.
- HATFIELD, M. O. Shielding effectiveness measurements using mode stirred chambers: A comparison of two approaches. IEEE Trans. Electromagn. Compat., Aug. 1998, vol. 30, no. 3.
- CRAWFORD, M. L., KOEPKE, G. H. Design, evaluation, and use of a reverberation chamber for performing electromagnetic susceptibility/ vulnerability measurements. NBS Tech. Note 1092, Apr. 1986.
- KRZYSZTOFIK, W. J., BOROWIEC, R., BIEDA, B. Optimization of nested reverberation chambers setup for shielding effectiveness measurements. Scientific Report, Nr I-28/09/S/107, Wroclaw University of Technology, Wroclaw, Poland, 2009.
- BALANIS, C. A. Advanced Engineering Electromagnetics, John Wiley & Sons, Inc., New York, 1989, p.235.
- KRZYSZTOFIK, W.J., BOROWIEC, R., BIEDA, B. Design consideration of nested reverberation chambers for shielding effectiveness testing. In 20th Int. Conf. on Applied Electromagnetics and Communications. ICECom-2010, Dubrovnik(Croatia), 2010.

Keywords: Shielding effectiveness, planar screening material, measuring methods, nested reverberation chamber, numerical electromagnetic computational methods

**M. Duran-Sindreu, P. Velez, J. Bonache, F. Martin**
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Broadband Microwave Filters Based on Open Split Ring Resonators (OSRRs) and Open Complementary Split Ring Resonators (OCSRRs): Improved Models and Design Optimization

The paper is focused on the design of broadband bandpass filters at microwave frequencies. The proposed filters are based on a combination of open split ring resonators (OSRRs) and open complementary split ring resonators (OCSRRs) loaded in a host transmission line. Since these resonators (OSRRs and OCSRRs) are electrically small, the resulting filters are compact. As compared to previous papers by the authors on this topic, the main aim and originality of the present paper is to demonstrate that by including a new series inductance in the circuit model of the OCSRR, it is possible to improve the predictions of these filter models and better fit the measured filter responses. Moreover, the parameter extraction method of the new circuit model and an automated filter design technique is introduced and demonstrated. The paper is complemented with the design and comparison of several prototypes.

- PENDRY, J.B., HOLDEN, A.J., ROBBINS, D.J., STEWART, W.J. Magnetism from conductors and enhanced nonlinear phenomena. IEEE Transactions Microwave Theory Tech., 1999, vol. 47, p. 2075-2084.
- FALCONE, F., LOPETEGI, T., BAENA, J.D., MARQUES, R., MARTIN, F., SOROLLA, M. Effective negative-ε stop-band microstrip lines based on complementary split ring resonators. IEEE Microwave and Wireless Components Letters, June 2004, vol. 14, p. 280-282.
- BILOTTI, F., TOSCANO, A., VEGNI, L. Design of spiral and multiple split-ring resonators for the realization of miniaturized metamaterial samples. IEEE Transactions on Antennas and Propagation, August 2007, vol. 55, p. 2258-2267.
- BILOTTI, F., TOSCANO, A., VEGNI, L., ALICI, K.B., AYDIN, K., OZBAY, E. Equivalent circuit models for the design of metamaterials based on artificial magnetic inclusions. IEEE Transactions on Microwave Theory and Techniques, December 2007, vol. 55, p. 2865-2873.
- GIL, I., BONACHE, J., GIL, M., GARCIA-GARCIA, J., MARTIN, F. Left handed and rigth handed transmission properties of microstrip lines loaded with complementary split rings resonators. Microwave and Optical Technology Letters, December 2006, vol. 48, p. 2508-2511.
- GIL, M., BONACHE, J., SELGA, J., GARCIA-GARCIA, J., MARTIN, F. Broadband resonant type metamaterial transmission lines. IEEE Microwave and Wireless Components Letters, vol. 17, February 2007, p. 97-99.
- GIL, M., BONACHE, J., GARCIA-GARCIA, J., MARTEL, J., MARTIN, F. Composite right/left handed (CRLH) metamaterial transmission lines based on complementary split rings resonators (CSRRs) and their applications to very wide band and compact filter design. IEEE Transactions on Microwave Theory and Techniques, June 2007, vol. 55, p. 1296-1304.
- MARTEL, J., MARQUES, R., FALCONE, F., BAENA, J.D., MEDINA, F., MARTIN, F., SOROLLA, M. A new LC series element for compact bandpass filter design. IEEE Microwave Wireless Components Letters, May 2004, vol. 14, p. 210-212.
- VELEZ, A., AZNAR, F., BONACHE, J., VELAZQUEZAHUMADA, M.C., MARTEL, J., MARTIN, F. Open complementary split ring resonators (OCSRRs) and their application to wideband CPW bandpass filters. IEEE Microwave and Wireless Components Letters, April 2009, vol. 19, p. 197-199.
- DURAN-SINDREU, M., VELEZ, A., AZNAR, F., SISO, G., BONACHE, J., MARTIN, F. Application of open split ring resonators and open complementary split ring resonators to the synthesis of artificial transmission lines and microwave passive components. IEEE Trans. Microwave Theory and Techniques, Dec. 2009, vol. 57, p. 3395-3403.
- DURAN-SINDREU, M., VELEZ, P., BONACHE, J., MARTIN, F. Broadband microwave filters based on metamaterial concepts. In 20th International Conference on Applied Electromagnetics and Communications. Dubrovnik (Croatia), 20 – 23 September 2010.
- DURAN-SINDREU, M., VELEZ, P., BONACHE, J., MARTIN, F. High-order coplanar waveguide (CPW) filters implemented by means of open split ring resonators (OSRRs) and open complementary split ring resonators (OCSRRs). Metamaterials, accepted (DOI: 10.1016/ j.metmat.2011.03.002).
- DISHAL, M. Design of dissipative band-pass filters producing desired exact amplitude-frequency characteristics. Proceedings of the I.R.E., September 1949, vol. 37, p. 1050-1069.
- DURAN-SINDREU, M., VELEZ, A., SISO, G., VELEZ, P., SELGA, J., BONACHE, J., MARTIN, F. Recent advances in metamaterial transmission lines based on split rings. Proceedings of the IEEE, accepted (DOI: 10.1109/JPROC.2011.2114870).

Keywords: Bandpass filters, metamaterials, open split ring resonator, open complementary split ring resonator.

**S. Costanzo, A. Borgia, I. Venneri, G. Di Massa**
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Millimeter-Waves Structures on Benzocyclobutene Dielectric Substrate

The need of low-loss substrate materials with stable dielectric performances is a strong requirement when working at millimeter frequencies, where standard dielectrics exhibit prohibitive losses. In this paper, the authors focus their attention on a polymer material, the benzocyclobutene (BCB), having a low dielectric constant and a low loss tangent, with a stable behavior up to THz frequencies. A specific in-house manufacture technology is described to realize millimeter-wave structures on a BCB dielectric substrate. Experimental validations on BCB-based circuits and antennas prototypes are discussed.

- Dow Corning. Sylgard 184 Silicone Elastomer. [Online]. Available at: http://www.dowcorning.com.
- HD MicroSystems. PI-2525, PI-2555, PI-2556 & PI-2574 Polymide. [Online]. Available at: http://www2.dupont.com.
- Specialty Coating Systems. SCS Parylene Properties. [Online]. Available at: http://www.scscoatings.com.
- COSTANZO, S., VENNERI, F., BORGIA, A., VENNERI, I., DI MASSA, G. 60 GHz microstrip reflectarray on a benzocyclobutene dielectric substrate. IET Science, Meas. Technology, 2011, vol. 5, no. 4, p. 134 - 139.
- CARRILLO-RAMIREZ, R., JACKSON, R. W. A highly integrated millimeter-wave active antenna array using BCB and silicon substrate. IEEE Trans. Microwave Theory and Tech., 2004, vol. 52, no. 6, p. 1648 - 1653.
- SEOK, S., ROLLAND, N., ROLLAND, P. Design, fabrication, and measurement of benzocyclobutene polymer zeo-level packaging for millimetre-wave applications. IEEE Trans. Microwave Theory and Tech., 2007, vol. 55, no. 5, p. 1040 - 1045.
- GRZYB, J., RUIZ, I., COTTET, D., TROSTER, G. An investigation of the material and process parameters for thin-film MCM-D and MCM-L technologies up to 100 GHz. In Proceedings of the 2003 Electronic Components and Technology Conf., 2003, p. 478 - 486.
- KRISHNAMURTHY, V. B., COLE, H. S., SITNIK-NIETERS, T. Use of BCB in gih-frequency MCM interconnects. IEEE Trans. Comp., Packag., and Manufact. Tech. – Part B, 1996, vol. 19, no. 1, p. 42 - 47.
- CHINOY, P. B., TAIADOD, J. Processing and microwave characterization of multilevel interconnects using benzocyclobutene dielectric. IEEE Trans. Comp., Packag., and Manufact. Tech. – Part B, 1993, vol. 16, no. 7, p. 714 - 719.
- Dow Chemical. Cyclotene 3000 Series Advanced Electron Resins. [Online]. Available at: http://www.dow.com/cyclotene.
- COSTANZO, S., VENNERI, I., DI MASSA, G., BORGIA, A. Benzocycloutene as substrate material for planar millimeter-wave structures: dielectric characterization and application. Journal of Infrared, Millimeter and Terahertz Waves, 2010, vol. 31, no. 1, p. 66 - 77.

Keywords: Millimeter-wave, benzocyclobutene, low-loss materials.

**Z. Raida, P. Kadlec, P. Kovacs, J. Lacik, Z. Lukes, M. Pokorny, P. Vsetula, D. Wolansky**
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Multi-objective Synthesis of Antennas from Special and Conventional Materials

In the paper, we try to provide a comprehensive look on a multi-objective design of radiating, guiding and reflecting structures fabricated both from special materials (semiconductors, high-impedance surfaces) and conventional ones (microwave substrates, fully metallic antennas). Discussions are devoted to the proper selection of the numerical solver used for evaluating partial objectives, to the selection of the domain of analysis, to the proper formulation of the multi-objective function and to the way of computing the Pareto front of optimal solutions (here, we exploit swarm-intelligence algorithms, evolutionary methods and self-organizing migrating algorithms). The above-described approaches are applied to the design of selected types of microwave antennas, transmission lines and reflectors. Considering obtained results, the paper is concluded by generalizing remarks.

- BOERINGER, D. W., WERNER, D. H. Bezier representations for the multi-objective optimization of conformal array amplitude weights. IEEE Transactions on Antennas and Propagation, 2006, vol. 54, no. 7, p. 1964–1970.
- FANGLEI SUN; LI, V.O.K.; ZHIFENG DIAO Modified bipartite matching for multi-objective optimization: Application to antenna assignments in MIMO systems. IEEE Transactions on Wireless Communications, 2009, vol. 8, no. 3, p. 1349–1355.
- LU, J., IRELAND, D., LEWIS, A. Multi-objective optimization in high frequency electromagnetics – an effective technique for smart mobile terminal antenna (SMTA) design. IEEE Transactions on Magnetics, 2009, vol. 45, no. 3, p. 1072–1075.
- GOUDOS, S. K., ZAHARIS, Z. D., KAMPITAKI, D. G., REKANOS, I. T., HILAS, C. S. Pareto optimal design of dual-band base station antenna arrays using multi-objective particle swarm optimization with fitness sharing. IEEE Transactions on Magnetics, 2009, vol. 45, no. 3, p. 1522–1525.
- PETKO, J. S., WERNER, D. H. Pareto optimization of thinned planar arrays with elliptical main-beams and low sidelobe levels. IEEE Transactions on Antennas and Propagation, 2011, vol. 59, no. 5, p. 1748–1751.
- CHAMAANI, S., MIRTAHERI, S. A., ABRISHAMIAN, M. S. Improvement of time and frequency domain performance of antipodal Vivaldi antenna using multi-objective particle swarm optimization. IEEE Transactions on Antennas and Propagation, 2011, vol. 59, no. 5, p. 1738–1742.
- JOHNSON, J. M., RAHMAT-SAMII, Y. Genetic algorithms in engineering electromagnetics. IEEE Antennas and Propagation Magazine, 1997, vol. 39, no. 4, p. 7–25.
- ROBINSON, J., RAHMAT-SAMII, Y. Particle swarm optimization in electromagnetics. IEEE Transactions on Antennas and Propagation, 2004, vol. 52, no. 2, p. 397–407.
- KADLEC, P., RAIDA, Z. Comparison of novel multi-objective self-organizing migrating algorithm with conventional methods. In Proceedings of the 21st International Conference Radioelektronika. Brno (Czech Republic), p. 97–100, 2011.
- YUAN, M., SARKAR, T. K., KOLUNDZIJA, B. Solution of large complex problems in computational electromagnetics using higherorder basis in MoM with out-of-core solvers. IEEE Antennas and Propagation Magazine, 2006, vol. 48, no. 2, p. 55–62.
- HODGES, R. E., RAHMAT-SAMII, Y. An iterative current-based hybrid method for complex structures. IEEE Transactions on Antennas and Propagation, 1997, vol. 45, no. 2, p. 265 – 276.
- JIAYUAN FANG, ZHONGHUA WU Generalized perfectly matched layer-an extension of Berenger's perfectly matched layer boundary condition. IEEE Microwave and Guided Wave Letters, 1995, vol. 5, no. 12, p. 451–453.
- KHEBIR, A., KOUKI, A. B., MITTRA, R. Asymptotic boundary conditions for finite element analysis of three-dimensional transmission line discontinuities. IEEE Transactions on Microwave Theory and Techniques, 1990, vol. 38, no. 10, p. 1427–1432.
- FROST, O. L. An algorithm for linearly constrained adaptive array processing. Proc. of the IEEE, 1072, vol. 60, no. 8, p. 926 to 935.
- FENN, A. J., KING, G. A. Experimental investigation of an adaptive feedback algorithm for hot spot reduction in radio-frequency phased-array hyperthermia. IEEE Transaction on Biomedical Engineering, 1996, vol. 43, no. 3, p. 273–280.
- KADLEC, P., STUMPF, M., RAIDA, Z. Adaptive beam forming in time-domain. In Proceedings of the International Conference on Electromagnetics in Advanced Applications ICEAA 2011. Torino (Italy), accepted for publication.
- STUMPF, M., DE HOOP, A. T., LAGER, I. E. Closed-form time domain expressions for the 2D pulsed EM field radiated by an array of slot antennas with finite width. In Proc. of the Int. Symp. on Electromagnetic Theory, Berlin (Germany), p. 703–706, 2010.
- KADLEC, P., RAIDA, Z. A novel multi-objective self-organizing migrating algorithm. Radioengineering, 2011, vol. 20, no. 4, p. 804-816.
- RAO, S. M. Time Domain Electromagnetics. London: Academic Press, 1999.
- LACIK, J., RAIDA, Z. Modeling microwave structure in time domain using Laguerre polynomials. Radioengineering, 2006, vol. 15, no. 3, p. 1–9.
- LACIK, J., LAGER, I. E., RAIDA, Z. Multicriteria optimization of antennas in time domain. Radioengineering, 2010, vol. 19, no. 1, p. 105–110.
- ROBINSON, J., RAMAT-SAMII, Y. Particle swarm optimization in electromagnetics. IEEE Transactions on Antennas and Propagation, 2004, vol. 52, no. 2, p. 397–407.
- RAO, S. M., WILTON, D. R., GLISSON, A. W. Electromagnetic scattering by surfaces of arbitrary shape. IEEE Transactions on Antennas and Propagation, 1982, vol. 30, no. 3, p. 409–418.
- SIEVENPIPER, D., ZHANG, L., BROAS, R. F. J., ALEXOPOULOS, N. G., YABLONOVITCH, E. High-impedance electromagnetic surfaces with a forbidden frequency band. IEEE Transactions on Microwave Theory and Techniques, 1999, vol. 47, no. 1, p. 2059–2074.
- CLAVIJO, S., DIAZ, R. E., MCKINZIE, W. E. Design methodology for Sievenpiper high-impedance surfaces: an artificial magnetic conductor for positive gain electrically small antennas. IEEE Transactions on Antennas and Propagation, 2003, vol. 51, no. 10, p. 2678–2690.
- KOVACS, P., RAIDA, Z. Global evolutionary algorithms in the design of electromagnetic band gap structures with suppressed surface waves propagation. Radioengineering, 2010, vol. 19, no. 1, p. 122–128.
- ELKAMEHOUCHI, H. M., EL-SALAM, M. N. A. Disc-cone antenna design using conducting wires and fractal geometry. In Proceedings of the Radio Science Conference, 2008. National Digital Object Identifier: 10.1109/NRSC.2008.4542312, 2008, p. 1–8.
- BALLESTER, P. J., CARTER, J. N. An effective real-parameter genetic algorithm with parent centric normal crossover for multimodal optimization. In Proceedings of the Genetic and Evolutionary Computation Conference GECCO’04. Seattle (USA), 2004, Springer-Verlag, 2004, p. 901–913.
- BALANIS, C. A. Antenna Theory: Analysis and Design. 2nd Edition. New York: John Wiley and Sons, 1997.
- JORDAN, E. C., BALMAIN, K. G. Electromagnetic Waves and Radiating Systems. 2nd Edition. Englewood Cliffs: Prentice Hall, 1968.
- POCHAZKA, M. Antennas – Handbook. 3rd Edition. Prague: BEN Publishing, 2005 (in Czech). [1.] OOI, B.-L., QUIN, S., LEONG, M.-S. Novel design of broad-band stacked patch antenna. IEEE Transaction on Antennas and Propagation, 2002, vol. 50, no. 10, p. 1391–1395. [2.] LEVINE, E., MALAMUD, S., SHTRIKMAN, S., TREVES, D. A study of microstrip array antennas with feed network. IEEE Transaction on Antennas and Propagation, 1989, vol. 37, no. 4, p. 426–434.
- FLEMING, P. L. The active medium propagation device. Proceedings of the IEEE, 1975, vol. 63, no. 8, p. 1253–1254.
- LIOUBTCHENKO, D. V., TRETYAKOV, S., DUDOROV, S. Millimeter-Wave Waveguides, Boston: Kluwer Academic Publishers, 2003.
- POKORNY, M. Modeling of Microwave Semiconductor Structures, Doctoral thesis, Brno: Brno University of Technology, 2011.
- REES, H. Hot Electron effect at microwave frequencies in GaAs, Solid State Communications, 1969, vol. 7, p. 267–269.
- SHUR, M. GaAs Devices and Circuits. London - New York: Springer, 1987.
- SZE, S. M. Physics of Semiconductor Devices. 3rd edition. Wiley- Interscience, 2007.

Keywords: Semiconductor antennas, conical antennas, planar antennas, fractal antennas, multi-objective optimization, evolutionary algorithms, swarm intelligence algorithms, self-organizing migrating algorithms, antenna measurements.

**P. Kadlec, Z. Raida**
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A Novel Multi-Objective Self-Organizing Migrating Algorithm

In the paper, a novel stochastic Multi-Objective Self Organizing Migrating Algorithm (MOSOMA) is introduced. For the search of optima, MOSOMA employs a migration technique used in a single-objective Self Organizing Migrating Algorithm (SOMA). In order to obtain a uniform distribution of Pareto optimal solutions, a novel technique considering Euclidian distances among solutions is introduced. MOSOMA performance was tested on benchmark problems and selected electromagnetic structures. MOSOMA performance was compared with the performance of the Non-dominated Sorting Genetic Algorithm II (NSGA-II) and the Strength Pareto Evolutionary Algorithm 2 (SPEA2). MOSOMA excels in the uniform distribution of solutions and their completeness.

- JOHNSON, J. M., RAHMAT-SAMII, V. Genetic algorithms in engineering electromagnetics. IEEE Antennas and Propagation Magazine, 1997, vol.39, no.4, p.7 - 21.
- ROBINSON, J., RAHMAT-SAMII, Y. Particle swarm optimization in electromagnetics. IEEE Transactions on Antennas and Propagation, 2004, vol. 52, no. 2, p. 397 - 407.
- ONWUBOLU, G. C., BABU, B. V. New Optimization Techniques in Engineering. Berlin, Germany: Springer, 2004.
- DEB, K. Multi-Objective Optimization using Evolutionary Algorithms. Chichester, UK: Wiley, 2001.
- DEB, K., PRATAP, A., AGARWAL, S., MEYARIVAN, T. A fast and elitist multiobjective genetic algorithm: NSGA-II. IEEE Transactions on Evolutionary Computation, 2002, vol. 6, no. 2, p. 182 - 197.
- ZITZLER, E., LAUMANNS, M., THIELE, L. SPEA2: Improving the strength Pareto evolutionary algorithm. Technical report 103, Zurich, Switzerland: Computer Engineering and Networks Laboratory (TIK), Swiss Federal Institute of technology (ETH), 2001.
- REYES-SIERRA, M., COELLO COELLO, C. A. Multi-objective particle swarm optimizers: a survey of the state-of-the-art. International Journal of Computational Intelligence Research, 2006, vol. 2, no. 3, p. 287 - 308.
- SEDENKA, V., RAIDA, Z. Critical comparison of multi-objective optimization methods: genetic algorithms versus swarm intelligence. Radioengineering, 2010, vol. 19, no. 3, p. 369 - 377.
- ZELINKA, I., LAMPINEN, J. SOMA – Self organizing migrating algorithm. In Proceedings of 6th MENDEL International Conference on Soft Computing. Brno (Czech Republic), 2000, p. 76 - 83.
- FIELDSEND, J. E., EVERSON, R. M., SINGH, S. Using unconstrained elite archives for multiobjective optimization. IEEE Transactions on Evolutionary Computation, 2003, vol. 7, no. 3, p. 305 - 323.
- VELDHUIZEN, D. V. Multiobjective evolutionary algorithms: classifications, analyses and new innovations. Ph.D. Thesis, Dayton, OH, Air Force Institute of Technology. Technical report No. AFIT/DS/ENG/99-01, 1999, 270 pp.
- ZITZLER, E., DEB, K., THIELE, L. Comparison of multiobjective evolutionary algorithms: Empirical results. Evolutionary Computation Journal, 2000, vol. 8, no. 2, p.125 - 148.
- MARADEI, F. A frequency-dependent WETD formulation for dispersive materials. IEEE Transactions on Magnetics, 2001, vol. 37, no. 5, p. 3303 - 3306.
- HARRINGTON, R. F. Time-Harmonic Electromagnetic Fields. New York, US: McGraw-Hill, 1961.

Keywords: Multi-objective optimization, self-organizing migrating algorithm, Pareto front of optimal solutions.

**J. Bartyzal, T. Bostik, P. Kovacs, T. Mikulasek, J. Puskely, Z. Raida, L. Slama, J. Vorek, D. Wolansky**
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Antenna Arrays for Tactical Communication Systems: A Comparative Study

In this paper, we give a comparative study of several planar antenna concepts for reliable long range links in a tactical environment. The antenna elements are studied in terms of their electrical properties (bandwidth, reflection coefficient and radiation characteristics) and construction (robustness and material consumption). First, we model single antenna elements to investigate if they meet the requirements. Second, we arrange the elements with the best features into 2x2 arrays. Computer simulations of the arrays are verified by measurements. Finally, we formulate recommendations for large array (8x8 or 16x16 elements) synthesis to achieve the required properties.

- LEE, K. F., CHEN, W. (Eds.) Advances in Microstrip and Printed Antennas. New York: John Wiley and Sons, p. 53-63 and p. 71- 121, 1997.
- POZAR, D. M. Microstrip antenna aperture-coupled to a microstripline. Electronics Letters, 1985, vol. 21, no. 2, p. 49-50.
- OOI, B.-L., QIN, S., LEONG, M.-S. Novel design of broad-band stacked patch antenna. IEEE Transaction on Antennas and Propagation, 2002, vol. 50. no. 10, p. 1391-1395.
- BHALLA, R., SHAFAI, L. Resonance behavior of single U-slot microstrip patch antenna. Microwave and Optical Technology Letters, 2002, vol. 32, no. 5, p. 333–335.
- HUYNH, T., LEE, K.-F. Single-layer single-patch wideband microstrip antenna. Electronics Letters, 1995, vol. 31, no. 16, p. 1310-1312.

Keywords: Planar antenna array, tactical communication systems, aperture-fed antenna, stacked-patch antenna, E-shaped patch antenna, U-slot patch antenna, feeding network

**O. Moravek, K. Hoffmann**
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Improvement to Load-pull Technique for Design of Large-signal Amplifier in K band

An improvement to the load-pull technique for a large-signal design of a transistor amplifier is proposed. On the contrary to the current load-pull technique – a small-signal pre-matching on the output of the transistor is applied which results in reduced demands on a maximum VSWR of the tuner. This minimizes the launcher radiation in the K band and reduce measurement uncertainty. The proposed method has been verified on a design of 22 GHz large-signal amplifier using a Excelics EPA018A-70 transistor.

- MEDIAVILLA, A. Equivallent circuit modelling theory and HEMT. In ITSS 2009 Summer School Proceedings. Rome (Italy), 2009.
- TAKAYAMA, Y. A new load-pull characterization method for microwave power transistors. In 1976 IEEE-MTT-S International Microwave Symposium. Cherry Hill (NJ, USA), 1976, p. 218 - 220.
- HASHMI, M. S., GHANNOUCHI, F. M., TASKER, P. J., RAWAT, K. Highly reflective load-pull. IEEE Microwave Magazine, 2011, vol. 12, no. 4, p. 96 - 107.
- Maury Microwave Inc., Ontario, California. 3.5 mm AUTOMATED TUNERS - 4.0 TO 26.5 GHz. 2 pages. [Online] Cited 2010-10-20. Available at: http://www.maurymw.com/datasheets/4T-075.pdf.
- RABOCH, J., HOFFMANN, K., ˇSKVOR, Z., HUDEC, P. Hidden problems in precise calibration on microstrip. In Proceedings of 72nd ARFTG Microwave Measurement Symposium Fall 2008. Portland (OR, USA), 2008, p. 37 - 39.
- ZELENY´ , J. Tranzistorovy´ oscila´tor (diploma thesis). Prague (Czech Republic): Czech Technical University in Prague, 2009.
- VENDELIN, G., PAVIO, A., ROHDE, U. Microwave Circuit Design using Linear and Nonlinear Techniques. New York: Wiley, 1992.
- Excelics Semiconductor, Inc. EPA018A-70 (datasheet). 2 pages. [Online] Cited 2010-11-23. Available at: http://www.excelics.com/ /Excelics/PDF/Datasheet/p018a70.pdf.

Keywords: K frequency band, large-signal measurement, load-pull, microstrip launcher radiation, large-signal amplifier, small-signal pre-matching

**R. Dvorak, T. Urbanec**
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Data Processing in Multiport-Based Reflectometer System

The paper describes operations with DC output voltage of multiport based system. Proposed system is based on the same principle as common six ports systems, however the used coupler has more outputs. This allows extension of bandwidth and higher precision of the measurement. To process measured data standard six port system calculations are used. To get more accurate results than in the case of simple six port system additional statistical methods can be used. The higher number of outputs produces large amount of measurement and calibration data, however using described technique this amount of data were reduced.

- ENGEN, G. F. The six-port reflectometer: An alternative network analyzer. IEEE Trans. Microwave Theory Tech., Dec. 1977, vol. MTT-25, p. 1075-1080.
- ENGEN, G. F. Calibrating the six-port reflectometer by means of sliding terminations. IEEE Trans. Microwave Theory Tech., Dec. 1978, vol. MTT-26, p. 951-957.
- SOMLO, P. I., HUNTER, J. D. Microwave Impedance Measurement. London, UK: Peter Peregrinus Ltd., p. 183-198.
- GHANNOUCHI, F. M., MOHAMMADI A. The Sixport Technique with Microwave and Wireless Application. Artech House Publishers, Sep. 2009. ISBN-10: 1608070336.
- WU, G., XU, H., HESLER, J. L., LICHTENBERGER, A. W., WEIKLE, R. M. A six-port reflectometer for in-situ monitoring of frequency multipliers. In Proceedings of the IMS 2009: Millimeter Wave and Terahertz Components and Technologies 2009.
- YAKABE, T., HIROSE, K., MATSUURA, H., FUJII, K., XIAO, F. An X-band MMIC six-port correlator based vector network analyzer. In Proceedings of 2010 Conference on Precision Electromagnetic Measurements. June 13-18, 2010, p.714-715.
- JUROSHEK, J. R., HOER, C. A. A dual six-port network analyzer using diode detectors. IEEE Tran. Microwave Theory Tech., Jan. 1984, vol. MTT-32, p. 78-83.
- DVORAK, R., URBANEC, T. Microwave diode detector for the sixport vector analyzer. In Proceedings of 19th International Conference Radioelektronika 2009. Brno (Czech Republic), 2009. p. 337-339. ISBN: 978-1-4244-3536- 4.
- HOER, C. Choosing line length for calibrating network analyzers. IEEE Transactions on Microwave Theory and Techniques, 1983.
- URBANEC, T. Special Methods for Microwave Vector Measurements. Brno University of Technology, Faculty of Electrical Engineering and Communication, 2008.
- HERSCHER, B. A., CARROLL, J. E. Optimal use of redundant information in multiport reflectometers by statistical methods. IEE Proc. H: Microwaves, Optics and Antennas, vol. 131, p. 25-30.
- DVORAK, R. URBANEC, T. Microwave vector measuring system. In Proceedings of ICECom 2010 20th International Conference on Applied Electromagnetic and Communications. Dubrovnik (Croatia), KoREMA, 2010, p. 40-43. ISBN: 978-953- 6037-58- 2.
- DVORAK, R., URBANEC, T. The wideband microwave measuring system. In Proceedings of the 33rd International Conference on Telecommunications and Signal Processing - TSP' 2010. Budapest (Hungary), 2010. p. 128-131. ISBN: 978-963- 88981-0- 4.
- HESSELBARTH, J., WIEDMANN, F., HYUART, B. Two new six-port reflectometers covering very large bandwidths. IEEE Tran. on Instrumentation and Measurement, 1997, vol. 46, no. 4, p. 966-970.
- POTTER, C. M., HJIPIERIS, G. Improvements in ultra-broadband TEM coupler design. In Proceedings of the IEEE Proceedings-H, April 1992, vol. 139, no. 2.
- WIEDMANN, F., HUYARD, B., BERGEAULT, E., JALLET, L. A. New robust method for six-port reflectometer calibration. IEEE Transactions on Instrumentation and Measurement, October 1999, vol. 48, no. 5.

Keywords: Six-port reflectometer, vector scattering parameters measurement, microwave detector, diode detector.

**W. Lu, W. Yan, D. Han, X. B. Zhao**
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Faraday Rotation Correction for Passive Microwave Remote Sensing from Space

Faraday rotation (FR) is one of the main error sources for passive microwave remote sensing from space especially in frequencies less than or equal to 10.7 GHz. In this paper, Faraday rotation correction for the vertical brightness temperature at L band and the third Stokes parameter brightness temperature at 10.7 GHz are discussed. Two approaches are studied to remove the influence of FR: correction by auxiliary data and correction by polarimetric mode. At 1.4 GHz, correction by polarimetric mode performs better than correction by auxiliary data. At 10.7 GHz, correction by auxiliary data is feasible while polarimetric mode correction becomes invalid. We propose a new method of using TEC data released by international GNSS service (IGS) for correction. It has been proved that the residual correction errors are reduced. IGS data method greatly improves the correction accuracy.

- ULABY, F. T., MOORE, R. K., FUNG, A. K. Microwave Remote Sensing: Active and Passive. Vol. 1-Microwave Remote Sensing Fundamentals and Radiometry. Massachusetts: Addison-Wesley Publishing Company, 1981.
- MARTINE, S. An Introduction to Ocean Remote Sensing. Cambridge: Cambridge University Press, 2004.
- YIN, X. B., LIU, Y. G., WANG, Z. Z. A new algorithm for microwave radiometer remote sensing of sea surface salinity and temperature. Scientia Sinica Terrae, 2006, vol. 40, no. 1, p. 1204―1211.
- BARRE, H. M. J. P., DUESMANN, B., KERR, Y. H. SMOS: the mission and the system. IEEE Transactions on Geoscience and Remote Sensing, 2008, vol. 46, no. 3, p. 587―593.
- VINE, D. M. L., LAGERLOEF, G. S. E., TORRUSIO, S. E. Aquarius and remote sensing of sea surface salinity from space. Proceedings of the IEEE, 2010, vol. 98, no. 5, p. 688―703.
- GAISER, P. W., TWAROG, E. M., LI, L. The WindSat space borne polarimetric microwave radiometer: sensor description and mission overview. In IGARSS 2004. New York: IEEE, 2004, vol. 1, p. 371―374.
- SHI, J. K. Studies on calibration and data preprocessing of fully polarimetric microwave radiometer. Master Dissertation. Nanjing: PLA University of Science & Technology, 2009.
- VINE, D. M. L., ABRAHAM, S. The effect of the ionosphere on remote sensing of sea surface salinity from space: absorption and emission at L Band. IEEE Transactions on Geoscience and Remote Sensing, 2002, vol. 40, no. 4, p. 771―782.
- ABRAHAM, S., VINE, D. M. L. Use of IRI to model the effect of ionosphere emission on earth remote sensing at L-band. Advances in Space Research, 2004, vol. 34, p. 2059―2066.
- ABRAHAM, S., VINE, D. M. L. Evaluation of IRI-95 to correct errors caused by Faraday rotation in passive microwave remote sensing from space. Advances in Space Research, 2001, vol. 27, no. 1, p 153―156.
- YUEH, S. H. Estimates of Faraday rotation with passive microwave polarimetry for microwave remote sensing of earth surfaces. IEEE Transactions on Geoscience and Remote Sensing, 2000, vol. 38, no. 5, p. 2434―2438.
- RIBO, S., MARTIN-NEIRA M. Faraday rotation correction in the polarimetric mode of MIRAS. IEEE Transactions on Geoscience and Remote Sensing, 2004, vol. 42, no. 7, p. 1405―1410.
- STOKES, G. G. On the composition and resolution of streams of polarized light from different sources. Trans Cambridge Phil Soc, 1852, vol. 9, p. 399―416.
- MEISSNER, T., WENTZ, F. J. Polarization rotation and the third Stokes parameter: the effects of spacecraft attitude and Faraday rotation. IEEE Transactions on Geoscience and Remote Sensing, 2006, vol. 44, no. 3, p. 506―515.
- VINE, D. M. L., ABRAHAM, S. Faraday rotation and passive microwave remote sensing of soil moisture from space. In: Pampaloni P, Paloscia S, eds. Microwave Radiometry and Remote Sensing of the Earth's Surface and Atmosphere. Zeist: VSP, 2000. p. 89―96.
- SHI, J. K., YAN, W., GONG, H. Y. Studies on Faraday rotation correction for fully polarimetric microwave radiometer at 10.7 GHz. Journal of Microwaves, 2009, vol. 25, no. 5, p. 79―83.
- FONT, J., CAMPS, A., BORGES, A. SMOS: The challenging sea surface salinity measurement from space. Proceedings of the IEEE, 2010, vol. 98, no. 5, p. 649―665.
- VINE, D. M. L., LAGERLOEF, G. S. E., COLOMB, F. R. Aquarius: an instrument to monitor sea surface salinity from space. IEEE Transactions on Geoscience and Remote Sensing, 2007, vol. 45, no. 7, p. 2040―2050.
- GAISER, P. W., GERMAIN, K. M. S., TWAROG, E. M. The WindSat spaceborne polarimetric microwave radiometer: sensor description and early orbit performance. IEEE Transactions on Geoscience and Remote Sensing, 2004, vol. 42, no. 11, p. 2347―2361.
- SKOU, N. Faraday rotation and L band oceanographic measurements. Radio Science, 2003, vol. 38, no. 4, p. 8059-8067.
- PINORI, S., CRAPOLICCHIO, R., MECKLENBURG, S. Preparing the ESA-SMOS (soil moisture and ocean salinity) mission - overview of the user data products and data distribution strategy. In MICRORAD 2008. New York: IEEE, 2008, vol. 1, p. 97―100.
- ZINE, S., BOUTIN, J., FONT, J. Overview of the SMOS sea surface salinity prototype processor. IEEE Transactions on Geoscience and Remote Sensing, 2008, vol. 46, no. 3, p. 621―645.
- YUEH, S. H. Modelling of wind direction signals in polarimetric sea surface brightness temperatures. IEEE Transactions on Geoscience and Remote Sensing, 1997, vol. 2, no. 35, p. 1400―1418.
- WANG, Z. Z. Sea surface wind vector measured by polarimetric microwave radiometer-principle, system design, and simulation study. Doctor Dissertation. Beijing: Center for Space Science and Applied Research, Chinese Academy of Sciences, 2005.
- PLONSKI, M., SMITH, C. Algorithm theoretical basis document (ATBD) for the conical-scanning microwave imager/sounder (CMIS) environmental data records (EDRs), volume 17: temperature data record and sensor data record algorithms version 2.0, Lexington: AER, 2001.
- HUDSON, D., PIEPMEIER, J. R., LONG, D. G. Polarization rotation correction in radiometry: an error analysis. IEEE Transactions on Geoscience and Remote Sensing, 2007, vol. 45, no. 10, p. 3212―3223.
- HUDSON, D. L., PIEPMEIER, J. R., LONG, D. G. Polarization rotation correction in radiometry: an extended error analysis. In IGARSS 2006. New York: IEEE, 2006, vol. 5, p. 2305―2308.
- KIM, S.–B., WENTZ, F. J. Brightness temperature retrieval with scale-model antenna patterns of the aquarius l-band radiometer. In IGARSS 2008. New York: IEEE, 2008, vol. 2, p. 1184―1187.
- WALDTEUFEL, P., FLOURY, N., DINNAT, E. P. Ionospheric effects for L-band 2-D interferometric radiometry. IEEE Transactions on Geoscience and Remote Sensing, 2004, vol. 42, no. 1, p. 105―118.
- MARTIN-NEIRA, M., RIBO, S., MARTIN-POLEGRE, A. J. Polarimetric mode of MIRAS. IEEE Transactions on Geoscience and Remote Sensing, 2002, vol. 40, no. 8, p. 1755―1768.
- VINE, D. M. L., JACOB, S. D., DINNAT, E. P. The influence of antenna pattern on Faraday rotation in remote sensing at L-Band. IEEE Transactions on Geoscience and Remote Sensing, 2007, vol. 45, no. 9, p. 2737―2746.
- KOUBA, J. A guide to using international GNSS service (IGS) products. [Online] Cited 2010-12-20. Available at: http://igscb.jpl.nasa.gov/igscb/resource/pubs/UsingIGSProductsVe r21.pdf.
- YAN, W., LU, W., SHI, J. K., et al. Remove the influence of Faraday rotation on passive microwave remote sensing from space. Acta Physica Sinica, 2011, no. 9, in press.

Keywords: Faraday rotation, Stokes parameter, polarimetric mode correction, correction by auxiliary data, international GNSS service (IGS)

**Y.Song, C.M.Tse**
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EM Scattering by a Conducting Sphere Coated with a Uniaxial Layer under Arbitrary Illumination Angle in a Fixed Laboratory Frame

Under a fixed laboratory frame, the electromagnetic theory of the scattering of a plane wave of arbitrary polarizations incidence from arbitrary angles by a uniaxial anisotropic medium was obtained for the first time, and could be solved analytically from an eigensystem determined by a uniaxial anisotropic medium. By applying the boundary conditions at respective interfaces of the coated spherical structure, the unknown expansion coefficients can be obtained from the incident field and the electromagnetic fields in the anisotropic medium, and from the scattered field. Not only did the numerical results demonstrate the validity of our proposed theory but this paper shall also provide discussions in relation to some general cases (under arbitrary incident angles) of bistatic radar cross section.

- KONG, J. A. Electromagnetic Wave Theory. Cambrige, MA: EMW Publishing, 2005.
- MIE, D. Beitrage zur Optik truber Medien speziell kolloidaler Metallosungen. Ann.Phys., 1908, vol. 25, p. 377-455.
- ADEN, A. L., M. KERKER, M. Scattering of electromagnetic wave from two concentric spheres. J. Appl. Phys. 1951, vol. 22, p. 1242-1246.
- KEENER, J. D., CHALUT, K. J., PYHTILA, J. W., WAX, A. Application of Mie theory to determine the structure of spheroidal scatterers in biological materials. Opt. Lett., 2007, vol. 32, no. 10, p. 1326-1328.
- GENG, Y. L., QIU, C.-W., YUAN, N. Exact solution to electromagnetic scattering by an impedance sphere coated with a uniaxial anisotropic layer. IEEE Trans. Antennas Propagat, 2009, vol. 57, no. 2, p. 572-576.
- GENG, Y. L., QIU, C.-W., ZOUHDI, S. Full-wave analysis of extraordinary backscattering by a layered plasmonic nanosphere. J. Appl. Phys., 2008, vol. 104, 034909.
- LIN, Z., CHUI, S. T. Electromagnetic scattering by optically anisotropic magnetic particle. Physical Review E, 2004, vol. 69, 056614.
- QIU, C.-W., LI, L. W., ZOUHDI, S., YEO, T. S., WU, Q. On the integral identities consisting of two spherical Bessel functions. IEEE Trans. Antennas Propagat, 2007, vol. 55, no. 1, p. 240-244.
- QIU, C.W., ZOUHDI, S., RAZEK, A. Modified spherical wave functions with anisotropy ratio: Application to the analysis of scattering by multilayered anisotropic shells. IEEE Trans Antennas Propagat, 2007, vol. 55, no. 12, p. 3515-3523.
- RICHMOND, J. H. Scattering by a ferrite-coated conducting sphere. IEEE Trans. Antennas Propag., 1987, vol. 35, p. 73–79.
- BOHREN, C. F., HUFFMAN, D. R. Absorption and Scattering of Light by Small Particles. New York: Wiley, 1983.
- QIU, C. W., LI, L. W., YEO, T. S., ZOUHDI, S. Scattering by rotationally symmetric anisotropic spheres: Potential formulation and parametric studies., Phys. Rev. E, 2007, vol. 75, 026609.
- LV, C. J., SHI, Y., LIANG, C. H. Higher order hierarchical Legendre basis functions application to the analysis of scattering by uniaxial anisotropic objects. Progress in Electromagnetics Research, 2010, vol .13, p133-143.
- GENG, Y. L., WU, X. B., LI, L. W., GUAN, B. R. Mie scattering by a uniaxial anisotropic sphere. Phys. Rev. E, 2004, vol. 70, no. 5, p. 056609.
- YU-LIN XU Electromagnetic scattering by an aggregate of spheres: Far field. Applied Optics, December 1997, vol. 36, no 36, p. 9496-9508.

Keywords: Electromagnetic scattering, radar cross section (RCS), uniaxial anisotropic media, perfect electric conductor (PEC), spherical vector function, incident angle, azimuthal angle, axial ratio

**P. Rezaee, M. Tayarani, R. Knochel**
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Miniaturized Microstrip Filter Design Using Active Learning Method

Relating coupling and external quality factor of a filter to the physical parameters of the structure which is the final step of any filter design is usually complicated due to geometrical complexities of the filter, or in the case of microstrip resonators due to the lack of the exact solution for the field distribution. Therefore, common approach is using time consuming full wave simulations. In this paper active learning method (ALM) which is a fuzzy-based modeling technique developed by a procedure algorithmically mimics the information-handling process of the human brain, is proposed to overcome this drawback. Modeling steps of an unknown function using ALM will be described using an illustrative example. Afterwards, the modeling approach will be implemented to model coupling factor between two coupled spiral resonators (SRs) for two different coupling structures and external quality factor of the same resonator. Accuracy of the extracted surfaces is validated using two different criteria. Using the extracted surfaces; a four pole chebychev bandpass filter was designed and fabricated. Good agreement between the measured response and simulation validated the accuracy of the extracted surfaces again. Comparing the fabricated SR filter with a square open loop resonator (SOLR) one demonstrates more than 70% of filter area reduction.

- MIRAFTAB, V., MANSOUR, R. R. Computer-aided tuning of microwave filters using fuzzy logic. IEEE Transact. on Microwave Theory and Techniques, 2002, vol. 50, no. 12, p. 2781 - 2788.
- MIRAFTAB, V., MANSOUR, R. R. A robust fuzzy-logic technique for computer-aided diagnosis of microwave filters. IEEE Transactions on Microwave Theory and Techniques, 2004, no. 1, vol. 52, p. 450 - 456.
- TAYARANI, M., KAMI, Y. Qualitative analysis in engineering electromagnetic; an application to general transmission lines. IEIEC Transactions on Electronics, 2001, vol. E84-C, no. 3, p. 364 – 375.
- GUNEY, K., SARIKAYA, N. Resonant frequency calculation for circular microstrip antennas with a dielectric cover using adaptive network-based fuzzy inference system optimized by various algorithms. Progress in Electromagnetics Research, PIER 72, 2007, p. 279 - 306.
- GUNEY, K., SARIKAYA, N. Concurrent neuro-fuzzy systems for resonant frequency computation of rectangular, circular and triangular microstrip antennas. Progress in Electromagnetics Research, PIER 84, 2008, p. 253 - 277.
- OSTADZADEH, S. R., SOLEIMANI, M., TAYARANI, M. A fuzzy model for computing input impedance of two coupled dipole antennas in the echelon form. Progress in Electromagnetics Research, PIER 78, 2008, p. 265 - 283.
- OSTADZADEH, S. R., SOLEIMANI, M., TAYARANI, M. A fuzzy model for computing back-scattering response from linearly loaded dipole antenna in the frequency domain. Progress in Electromagnetics Research, PIER 86, 2008, 229 - 242.
- KABIR, H., WANG, Y., YU, M., ZHANG, Q-J. High-dimensional neural-network technique and applications to microwave filter modelling. IEEE Transactions on Microwave Theory and Techniques, 2010, vol. 58, no.1, p. 145 - 156.
- TAKAGI, T., SUGENO, M. Fuzzy identification of systems and its application to modeling and control. IEEE Transactions on Systems, Man and Cybernetics, 1985, vol. SMC. 15, no. 1, p. 116 - 132.
- TAKAGI, T., SUGENO, M. A fuzzy logic approach to qualitative modelling. IEEE Transactions on Fuzzy Systems, 1993, vol. 1, no. 1, p. 1282 - 1285.
- SHOURAKI, S. B., HONDA, N. Recursive fuzzy modeling based on fuzzy interpolation. Journal of Advanced Computational Intelligence, 1999, vol. 3, no. 2, p. 114 - 125.
- SHOURAKI, S. B., HONDA, N. Fuzzy interpretation of human intelligence. International Journal of Uncertainty, Fuzziness and Knowledge-based Systems, 1999, vol. 7, no. 4, p. 407 - 414.
- HONG, J. S., LANCASTER, M. J. Coupling of microstrip square open-loop resonators for cross-coupled planar microwave filters. IEEE Transactions on Microwave Theory and Techniques, 1996, vol. 44, no.12, p. 2099 – 2109.
- RIZZI, P. A. Microwave Engineering: Passive Circuits. Prentice- Hall, 1988.
- HONG, J. S., LANCASTER, M. J. Canonical microstrip filter using square open-loop resonators. IET Electronics Letters, 1995, vol. 31, no. 23, p. 2020 – 2022.
- CHAIMOOL, S., KERDSUMANG, S., AKKARAEKTHALIN, P. A novel microstrip bandpass filter using triangular open-loop resonators. In Proceedings of the 9th IEEE Asia Pacefic Conference on Communication. Penang (Malaysia), 2003, p. 788 - 791.
- ROMANI, I. N. A., SOARES, J. M. A., ABDALLA, H. Compact microstrip bandpass filter with enhanced stopband performance. In Proceedings of the 12th IEEE International Microwave and Optoelectronics Conference. Salvador (Brazil), 2007, p. 950 - 953.
- MAO, R. J., TANG, X. H., WANG, L., DU, G. H. Miniaturized hexagonal stepped-impedance resonators and their applications to filters. IEEE Transactions on Microwave Theory and Techniques, 2008, vol. 56, no. 2, p. 440 - 448.

Keywords: Active learning method, coupling factor computation, external quality factor computation, soft computing techniques, spiral resonator.

**Liu Liu, Cheng Tao, Jiahui Qiu, Houjin Chen**
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An Performance Study for Sectorised Antenna based Doppler Diversity in High-Speed Railway Communications

The wireless channel of High-Speed Railway communication system is rapidly time-varying. The orthogonal frequency division multiplexing transmitting over this channel will be exposed to the intercarrier interference caused by large Doppler spread. The sectorised antenna can be employed for Doppler mitigation and obtaining Doppler diversity gain. In this paper the performance of this directional antenna is analyzed. The preferable partition scheme for the omnidirectional antenna and the optimal Doppler compensation frequency are addressed firstly. And the uncorrelated property of the signal received from the different sectorised antennas is demonstrated originally which can be utilized for Doppler diversity gain. Finally, it is proved by the simulation results that this architecture will allows us to achieve remarkable performance under high mobility conditions.

- XIN, D. Record-breaking train on track. China Daily, 2010. [Online]. Available at: http://www.chinadaily.com.cn/china/2010- 12/04/content 11651930.htm.
- PEIKER, E., TEICH, W. G., LINDNER, J. Windowing in the receiver for OFDM systems in high-mobility scenarios. Multi-Carrier Systems & Solutions 2009: Lecture Notes in Electrical Engineering, 2007, vol. 41, no. 1, p. 57 - 65.
- GE, R., SUN, S. ICI performance analysis for all phase OFDM systems. Journal of Electromagnetic Analysis and Applications, 2009, vol. 1, no. 2, p. 118 - 123.
- ZHAO, Y., HAGGMAN, S.-G. Intercarrier interference selfcancellation scheme for OFDM mobile communication systems. IEEE Transactions on Communications, 2001, vol. 49, no. 7, p. 1185 - 1191.
- PETER, K., REICHARDT, L., KAMMEYER, K.-D., ZWICK, T. MIMO-OFDM with Doppler Compensating Antennas in Rapidly Fading Channels. Multi-Carrier Systems & Solutions 2009: Lecture Notes in Electrical Engineering, 2009, vol. 41, no. 2, p. 69 - 78.
- KLENNER, P., K.-D. KAMMEYER, K.-D. Doppler-compensation for OFDM-transmission by sectorized antenna reception. In 6th International Workshop on Multi-Carrier Spread Spectrum MCSS 07. Herrsching (Germany), 2007.
- PATZOLD, M. Mobile Fading Channels: Modelling, Analysis and Simulation. New York: Wiley, 2002.
- NORKLIT, O., VAUGHAN, R. G. Angular partitioning to yield equal Doppler contributions. IEEE Transactions on Vehicular Technology, 1999, vol. 48, no. 5, p. 1437 - 1442.
- WEE TECK NG, DUBEY, V. K. Application of angular diversity in OFDM systems. In IEEE International Conference on Communications ICC 03. Anchorage (USA), 2003, vol. 5, p. 3433 - 3437.
- YE LI, CIMINI, L. J. JR. Bounds on the interchannel interference of OFDM in time-varying impairments. IEEE Transactions on Communications, 2001, vol. 49, no. 3, p. 401 - 404.
- RAPPAPORT, T. S. Wireless Communications: Principles and Practice. Upper Saddle River (NJ, USA): Prentice-Hall, 1999.
- FAILLI, M. Digital Land Mobile Radio Communications COST 207 Final Report. (European Commission, Tech. Rep.), 1989.
- ZTE Corporation. ZTE TD-SCDMA Radio Network Solution. [Online] Available at: http://wwwen.zte.com.cn/en/solutions /wireless/ td/Solution/200709/t20070926157324.html.

Keywords: Doppler diversity, sectorised antenna, High-Speed Railway.

**T. Gotthans, J. Petrzela**
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Experimental Study of the Sampled Labyrinth Chaos

In this paper, some new numerical as well as experimental results connected with the so-called labyrinth chaos are presented. This very unusual chaotic motion can be generated by mathematical model involving the scalar goniometrical functions which makes a three-dimensional autonomous dynamical system strongly nonlinear. Final circuitry implementation with analog core and digital parts can be used for modeling Brownian motion. From the viewpoint of generating chaotic motion by some electronic circuit, first step is to solve problems associated with the two-port nonlinear transfer functions synthesis. In the case of labyrinth chaos the finite dynamical range of the input variables introduced by the used active elements usually limits the performance greatly, similarly as it holds for the multi-grid spiral attractors. This paper shows an elegant way how to remove these obstacles by using uni-versal multiple-port with internal digital signal processing.

- SPROTT, J. C. Chaos and Time Series Analysis. Oxford University Press, 2003. 507 pages.
- BROWN, R. A brief account of microscopical observations made in the months of June, July and August, 1827, on the particles contained in the pollen of plants; and on the general existence of active molecules in organic and inorganic bodies. Philosophical Magazine, 1941, vol. 4, p. 161 - 174.
- SPROTT, J. C., CHLOUVERAKIS, K. E. Hyperlabyrinth chaos: From chaotic walks to spatiotemporal chaos. Chaos, 2007, vol. 17.
- SPROTT, J. C., CHLOUVERAKIS, K. E. Labyrinth chaos. International Journal of Bifurcation and Chaos, 2007, vol. 17, no. 6, p. 2097 - 2108.
- GRYGIEL, K., SZLACHETKA, P. Lyapunov exponents analysis of autonomous and nonautonomous set of ordinary differential equations. Acta Physica Polonica B, 1995, vol. 26, no. 8, p. 1321 to 1331.
- PETRZELA, J. Modeling of the Strange Behavior in the Selected Nonlinear Dynamical Systems, Part II: Analysis. Brno: Vutium Press, 2010.
- WOLF, A., SWIFT, J. B., SWINNEY, H. L., VASTANO, J. A. Determining Lyapunov exponents from a time series. Physica D, 1985, vol. 16.
- PETRZELA, J., GOTTHANS, T. Chaotic oscillators with single polynomial nonlinearity and digital sampled dynamics. Przeglad Electrotechniczny, 2011, vol. 3, no. 1, p. 161 - 163.
- ITOH, M. Synthesis of electronic circuits for simulating nonlinear dynamics. International Journal of Bifurcation and Chaos, 2001, vol. 11, no. 3, p. 605 - 653.
- PETRZELA, J. Modeling of the Strange Behavior in the Selected Nonlinear Dynamical Systems, Part I: Oscillators. Brno: Vutium Press, 2008.
- PETRZELA, J., POSPISIL, V. Nonlinear resistor with polynomial AV characteristic and its application in chaotic oscillator. Radioengineering, 2004, vol. 13, no. 2, p. 20 - 25.
- PETRZELA, J., GOTTHANS, T., HRUBOS, Z. Analog implementation of Gotthans-Petrzela oscillator with virtual equilibria. In Proceedings of the 21st International Conference Radioelektronika 2011. Brno (Czech Republic), 2011, p. 53 - 56.
- MUTHUSWAMY, B. CHUA, L. O. Simplest chaotic circuit. Int. J. of Bifurcation and Chaos, 2010, vol. 20, no. 5, p. 1567 - 1580.
- SPROTT, J. C., ZERAOULIA, E. Some open problems in chaos theory and dynamics. International Journal of Open Problems in Computer Science and Mathematics, 2011, vol. 4, p. 1 - 10.
- SPANY, V., GALAJDA, P., GUZAN, M., PIVKA, L., OLEJAR, M., Chua´s singularities: great miracle in circuit theory. International Journal of Bifurcation and Chaos, 2010, vol. 20, no. 10, p. 2993 - 3006.

Keywords: Analog oscillator, labyrinth chaos, signal processing, Lyapunov exponents, sampled dynamics.

**D. Cerny, J. Dobes**
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Common LISP as Simulation Program (CLASP) of Electronic Circuits

In this paper, an unusual and efficient usage of functional programming language Common LISP as simulation program (CLASP) for electronic circuits is proposed. The principle of automatic self-modifying program has enabled complete freedom in definition of methods for optimized solution of any problem and speeding up the entire process of simulation. A new approach to program structure in electronic circuit simulator CLASP is described. The definition of simple electronic devices as resistor, voltage source and diode is given all together with description of their memory management in program CLASP. Other circuit elements can be easily defined in the same way. Simulation methods for electronic circuits as linear and nonlinear direct current analysis (DC) are suggested. A comparison of performances of two different linear solvers (an original and the standard GNU GSL) for circuit equations is demonstrated by an algorithm for automatic generation of huge circuits.

- NAGEL, L.W., ROHRER, R. A. Computer analysis of nonlinear circuits, excluding radiation (CANCER). IEEE Journal of Solid-State Circuits, 1971, vol. 6, no. 4, p. 166 - 182.
- NAGEL, L. W. SPICE2: A Computer Program to Simulate Semiconductor Circuits. PhD thesis. Berkeley (CA, USA): University of California, 1975.
- HO, C.-W., RUEHLI, A. E., BRENNAN, P. A. The modified nodal approach to network analysis. IEEE Transactions on Circuits and Systems, 1975, vol. 22, no. 6, p. 504 - 509.
- PEDERSON, D. A historical review of circuit simulation. IEEE Transactions and Circuits and Systems, 1984, vol. 31, no. 1, p. 103 - 111.
- MCCARTHY, J. LISP 1.5 Programmer’s Manual. Cambridge (MA, USA): MIT Press, 1965.
- SEIBEL, P. Practical Common Lisp. New York: Apress, 2005.
- HIGHAM, N. Accuracy and Stability of Numerical Algorithms. Society for Industrial Mathematics, 2002.
- GOLDBERG, D. What every computer scientist should know about floating-point arithmetic. ACM Computing Surveys, 1991, vol. 23, no. 1, p. 5 - 48.
- SULI, E., MAYERS, D. An Introduction to Numerical Analysis. Cambridge (UK): Cambridge University Press, 2003.

Keywords: Common LISP, computer simulation, electronic circuits, device models

**C. Sakul, W. Jaikla, K. Dejhan**
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New Resistorless Current-mode Quadratur Oscillators Using 2 CCCDTAs and Grounded Capacitors

The current-mode quadrature oscillators using 2 current controlled current differencing transconductance amplifiers (CCCDTAs) and 2 grounded capacitors are presented. The proposed oscillators can provide 2 sinusoidal output currents with 90º phase difference. The oscillation condition and oscillation frequency can be electronically/independently controlled by adjusting the bias current of the CCCDTA. High output impedances of the configuration enable the circuit to be cascaded without additional current buffers. The use of only grounded capacitors is ideal for integration. The PSpice simulation results are depicted. The given results agree well with the theoretical anticipation.

- KHAN, I. A., KHAWAJA, S. An integrable gm-C quadrature oscillator. Int. J. Electronics, 2000, vol. 87, no. 11, p. 1353-1357.
- TOUMAZOU, C., LIDGEY, F. J. Universal active filter using current conveyors. Electron. Lett., 1986, vol. 22, no. 12, p. 662- 664.
- ABUELMA’ATTI, M. T., AL-ZAHER, H. A. Current-mode sinusoidal oscillators using single FTFN. IEEE Trans. Circuits and Systems-II: Analog and Digital Signal Proc., 1999, vol. 46, no. 1, p. 69-74.
- CAM, U., TOKER, A., CICEKOGLU, O., KUNTMAM, H. Current-mode high output-impedance sinusoidal oscillator configuration employing single FTFN. Analog Integrated Circuits and Signal Proc., 2000, vol. 24, p. 231-238.
- GUPTA, S. S., SENANI, R. Realization of current-mode SRCOs using all grounded passive elements. Frequenz, 2003, vol. 57, p. 26-37.
- BIOLEK, D. CDTA-building block for current-mode analog signal processing. In Proceedings of the European Conference on Circuit Theory and Design. Krakow (Poland), 2003, p. 397-400.
- BIOLEK, D., BIOLKOVA, V., KOLKA, Z. Current-mode biquad employing single CDTA. Indian Journal of Pure & Applied Physics, 2009, vol. 47, no. 7, p. 535-537.
- SHAH, N. A., IQBAL, S. Z., QUADRI, M. Current-mode bandpass filter using a single CDTA. J. of Active and Passive Electronic Devices, 2009, 4, p. 1-5.
- SIRIPRUCHYANUN, M., JAIKLA, W. Realization of current controlled current differencing transconductance amplifier (CCCDTA) and its applications. ECTI Transactions on Electrical Engineering Electronics and Communications, 2007, vol. 5, no. 1, p. 41-50.
- HORNG, J. W. Current-mode third-order quadrature oscillator using CDTAs. Active and Passive Electronic Components, 2009, p. 1-5.
- HORNG, J. W., LEE, H., WU, J. Y. Electronically tunable thirdorder quadrature oscillator using CDTAs. Radioengineering, 2010, vol. 19, no. 2, p. 326-330.
- KESKIN, A. U., BIOLEK, D. Current mode quadrature oscillator using current differencing transconductance amplifier (CDTA). IEE Proc.-Circuits Devices Syst., 2006, vol. 153, no. 3, p. 214-218.
- LAHIRI, A. New current-mode quadrature oscillator using CDTA. IEICE Electronics Express., 2009, vol. 6, no. 3, p. 135-140.
- UYGUR, A., KUNTMAN, H. CDTA-based quadrature oscillator design. In 14th European Signal Processing Conference (EUSIPCO 2006). Florence (Italy), 2006.
- TANGSRIRAT, W., TANJAROEN, W. Current-mode sinusoidal quadrature oscillator with independent control of oscillation frequency and condition using CDTAs. Indian Journal of Pure & Applied Physics, 2010, vol. 48, p. 363-366.
- BIOLEK, D., BIOLKOVA, V., KESKIN, A. U. Current mode quadrature oscillator using two CDTAs and two grounded capacitors. In Proc. of the 5th WSEAS International Conference on Systems, Science and Simulation in Engineering ICOSSE' 06. Puerto De La Cruz (Tenerife, Spain), 2006, p. 368-370.
- TANJAROEN, W., TANGSRIRAT, W. Resistorless current-mode quadrature sinusoidal oscillator using CDTAs. In Proc. of 2009 APSIPA Annual Summit and Conference. Sapporo (Japan), 2009.
- PRASAD, D., BHASKAR, D. R., SINGH, A. K. Realization of single-resistance-controlled sinusoidal oscillator: a new application of the CDTA. WSEAS Transactions on Electronics, 2008, vol. 5, no. 6, p. 257-259.
- JAIKLA, W., SIRIPRUCHYANUN, M., BAJER, J., BIOLEK, D. A simple current-mode quadrature oscillator using single CDTA. Radioengineering, 2008, vol. 17, no. 1, p. 33-40.
- JAIKLA, W., SIRIPRUCHYANUN, M. A versatile quadrature oscillator and universal biquad filter using dual-output current controlled current differencing transconductance amplifier. In Proc. of the 2006 International Symposium on Communications and Information Technologies, 2006, p. 1072-1075.
- JAIKLA, W., SIRIPRUCHYANUN, M. CCCDTAs-based versatile quadrature oscillator and universal biquad filter. In Proc.of 2007 ECTI conference, Thailand, 2007, p. 1065-1068.
- LAHIRI, A., MISRA, A., GUPTA, K. Novel current-mode quadrature oscillators with explicit-current-outputs using CCCDTA. In Proceeding of 19th International Radioelektronika Conference. Bratislava (Slovakia), 2009, p. 47-50.
- YONGAN, L. A New single MCCCDTA based Wien-bridge oscillator with AGC. Int. J. Electron. Commun. (AEU), only first 2011
- RODRIGUEZ-VAZQUEZ, A., LINARES-BARRANCO, B., HUERTAS, J. L., SANCHEZ-SINENCIO, E. On the design of voltage-controlled sinusoidal oscillators using OTAs. IEEE Trans. Circuits Syst., 1990, vol. 37, p. 198-211.
- ODAME, K., HASLER, P. An efficient oscillator design based on OTA Nonlinearity. In International Symposium on Circuits and Systems (ISCAS 2007). New Orleans (Louisiana, USA), 2007, p. 921-924.
- LINARES-BARRANCO, B., RODRIGUEZ-VAZQUEZ, A., SANCHEZ-SINENCIO, E., HUERTAS, J. L. 10 MHz CMOS OTA-C voltage-controlled quadrature oscillator. Electron. Lett., 1989, vol. 25, p. 765-767.
- ABUELMA’ATTI, M. T. A new electronically tunable integrable CCII-OTA-based active-C oscillator. European Transactions on Telecommunications, 1991, vol. 2, p. 353-355.
- ABUELMA’ATTI, M. T. A new minimum component active-C OTA-based linear voltage (current)-controlled sinusoidal oscillator. IEEE Transactions on Instrumentation and Measurement, 1990, vol. 39, p. 795-797.
- LINARES-BARRANCO, B., RODRIGUEZ-VAZQUEZ, A., SANCHEZ-SINENCIO, E., HUERTAS, J. L. CMOS OTA-C high-frequency sinusoidal oscillators. IEEE Journal of Solid-Stage Circuits, 1991, vol. 26, p. 160-165.
- KUNTMAN, H., OZPINAR, A. On the realization of DO-OTA-C oscillators. Microelectronics Journal, 1998, vol. 29, p. 991 to 997.
- ABUELMA’ATTI, M. T., ALMASKATI, R. H. Digitally programmable active-C OTA-based oscillator. IEEE Transactions on Instrumentation and Measurement. 1988, vol. 37, p. 320-322.
- SOTNER, R., JERABEK, J., PETRZELA, J., DOSTAL, T., VRBA, K. Electronically tunable simple oscillator based on singleoutput and multiple-output transconductor. IEICE Electronic Express, 2009, vol. 6, p. 1476-1482.
- BHASKAR, D. R., ABDALLA, K. K., SENANI, R. Electronically-controlled current-mode second order sinusoidal oscillators using MO-OTAs and grounded capacitors. Circuits and Systems, 2011, vol. 2, p. 65-73.
- SINGH, V. Equivalent forms of dual-OTA RC oscillators with application to grounded-capacitor oscillators. IEE Proceeding of Circuits Devices Systems, 2006, vol. 153, p. 95-99.
- SENANI, R. New electronically tunable OTA-C sinusoidal oscillator. Electron. Lett., 1989, vol. 25, p. 286-287.
- ABUELMA’ATTI, M. T. New minimum component electronically tunable OTA-C sinusoidal oscillators, Electron. Lett., 1989, vol. 25, p. 1114-1115.
- 3WK 163 41. Optocouplers with a Photoresistor. Tesla-Blatna, datasheet. [Online] Available at: www.tesla-blatna.cz.
- FREY, D. R. Log-domain filtering: an approach to current-mode filtering. IEE Processing Circuit Devices System., 1993, vol. 140, no. 6, p. 1993.

Keywords: Sinusoidal oscillator, CCCDTA, current-mode

**R. Senani, S. S. Gupta**
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Current-Mode Universal Biquad Using Current Followers: A Minimal Realization

A new universal biquad filter is presented which employs a minimum number of active elements (only three current followers (CF)) along with a minimum number of passive components (i.e. only two resistors and two capacitors). The new circuit provides all the five standard filter responses (namely lowpass, bandpass, highpass, notch and allpass) from the same structure without requiring any component matching conditions and with explicit current outputs available from high output impedance terminals. The workability of the proposed universal biquad, realised with unity-gain current followers implemented in 0.35 µm CMOS and operated from 1.65 volts DC power supplies, is established by SPICE simulations.

- IBRAHIM, M. A., MINAEI, S., KUNTMAN, H. A. 22.5 MHz current-mode KHN-biquad using differential voltage current conveyor and grounded passive elements. AEU- International Journal of Electronics and Communications, 2005, vol. 59, p. 311-318.
- LIU, S. I., CHEN, J. J., HWANG, Y. S. New current-mode biquad filters using current followers. IEEE Transactions on Circuits and Systems I, 1995, vol. 42, p. 380-383.
- CELMA, S., SABADELL, J., MARTINEZ, P.A. Universal filter using unity-gain cells. Electronics Letters, 1995, vol. 31, p. 1817-1818.
- ABUELMA'ATTI, M. T., AL-QAHTANI, M. A. Current-mode universal filters using unity-gain cells. Electronics Letters, 1996, vol. 32, p. 1077-1079.
- SENANI, R., GUPTA, S. S. Universal voltage-mode/current-mode biquad filter realised with current feedback op-amps. Frequenz, 1997, vol. 51, p. 203-208.
- ALZAHER, H. A., ISMAIL, M. Current-mode universal filter using unity gain cells. Electronics Letters, 1999, vol. 35, p. 2198-2200.
- GUPTA, S. S., SENANI, R. New voltage-mode/current-mode universal biquad filter using unity-gain cells. International Journal of Electronics, 2006, vol. 61, p. 769-775.
- SENANI, R. GUPTA, S. S. New universal filter using only current followers as active elements. AEU- International Journal of Electronics and Communications, 2006, vol. 60, p. 251-256.
- TORRES-PAPAQUI, L., TORRES-MUNOZ, D., TLELOCUAUTLE, E. Synthesis of VFs and CFs by manipulation of generic cells. Analog Integrated Circuits and Signal Processing, 2006, vol. 46, p. 99-102.
- BIOLEK, D., SENANI, R., BIOLKOVA, V., KOLKA, Z. Active elements for analog signal processing; classification, review and new proposals. Radioengineering 2008, vol. 17, p. 15-32.
- SOULIOTIS, G., HARITANTIS, I. Current-mode filters based on current mirror arrays. International Journal of Circuit Theory and Applications, 2008, vol. 36, p. 173-183.
- ALZAHER, H. A. A CMOS digitally programmable universal currentmode filter. IEEE Transactions on Circuits and Systems-II: Express Briefs, 2008, vol. 55, p. 758-762.
- JERABEK, J., VRBA, K. Multiple-Input Multiple-Output universal filter using current followers. In Proceedings of the 31th International Conference on Telecommunications and Signal Processing - TSP' 2008. Budapest, Hungary: Asszisztencia Szervezo Kft., 2008, p. 29-32.
- JERABEK, J., VRBA, K. Design of SIMO- type universal filter with adjustable parameters. In Proceedings of the 32nd International Conference on Telecommunications and Signal Processing - TSP' 2009. Budapest (Hungary): Asszistencia Szervezo Kft, 2009, p. 38-42.
- SIRIPRUCHYANUN, M., JAIKLA, W. Electronically controllable current-mode universal biquad filter using single DO-CCCDTA. Circuits, Systems and Signal Processing, 2008, vol. 27, p. 113-122.
- SOTNER, R., SLEZAK, J., DOSTAL, T., PETRZELA, J. Universal tunable current-mode biquad employing distributed feedback structure with MO- CCCII. Journal of Electrical Engineering, 2010, vol. 61, p. 52-56.
- JERABEK, J., SOTNER, R., VRBA, K. Fully-differential current amplifier and its application to universal and adjustable filter. In 2010 International Conference on Applied Electronics. Plzen: University of West Bohemia, 2010, p. 141-144.
- SOTNER, R., SLEZAK, J., DOSTAL, T. Influence of mirroring of current output responses through grounded passive elements. In Proceedings of the 20th International Conference Radioelektronika. Brno (Czech Republic), 2010, p. 177-180.
- SOTNER, R., PETRZELA, J., SLEZAK, J. Current-controlled currentmode universal biquad employing multi-output transconductors. Radioengineering, 2009, vol. 18, p. 285-294.

Keywords: Universal filters, current followers, current-mode circuits

**W. Tangsrirat, O. Channumsin**
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High-Input Impedance Voltage-Mode Multifunction Filter Using a Single DDCCTA and Grounded Passive Elements

In this paper, a novel single-input three-output (SITO) second-order multifunction active voltage filter with high-input impedance is proposed. The proposed circuit is based on using the recently reported active building block, namely differential difference current conveyor transconductance amplifier (DDCCTA). It employs one DDCCTA as active element together with one grounded resistor and two grounded capacitors as passive elements. The circuit still maintains the following advantageous features : (i) the simultaneous realization of lowpass, bandpass and highpass responses from the same topology, (ii) no requirements for component matching conditions, (iii) electronic controllability of important filter parameters, (iv) simpler structure due to contains only one DDCCTA and three passive elements, and (v) low sensitivity performance. The non-ideal gain effects of the developed filter are examined and PSPICE simulation results are included using 0.5 um MIETEC CMOS technology parameters.

- SENANI, R., GUPTA, S. S. New universal filter using only current followers as active elements. Int. J. Electron. Commun., 2006, vol. 60, p. 251-256.
- KESKIN, A. U. Multi-function biquad using single CDBA. Electrical Engineering, 2006, vol. 88, p. 353-356.
- IBRAHIM, M. A., KUNTMAN, H., CICEKOGLU, O. Single DDCC biquads with high input impedance and minimum number of passive elements. Analog Integr. Circ. Sig. Process., 2005, vol. 43, p. 71-79.
- MAHESHWARI, S. High performance voltage-mode multifunction filter with minimum component count. WSEAS Trans. Electronics, 2008, vol. 5, p. 244-249.
- LIAO, Y. Z., CHEN, H. P., LEE, W. T. Versatile universal voltage-mode filter employing minimum components. IEICE Electronics Express, 2009, vol. 6, no. 17, p. 1246-1252.
- YUCE, E. Voltage-mode multifunction filters employing a single DVCC and grounded capacitors. IEEE Trans. Instrum. Meas., 2009, vol. 58, no. 7, p. 2216-2221.
- CHEN, H. P., HSIEH, T. Y. Voltage-mode highpass, bandpass and lowpass filters using a single DVCC. In Proc. Progress in Electromag. Research Symp. Xi’an, (China), 2010, p. 517-520.
- HERENCSAR, N., VRBA, K., KOTON, J., LATTENBERG, I. The conception of differential-input buffered and transconductance amplifier (DBTA) and its application. IEICE Electronics Express, 2009, vol. 6, no. 6, p. 329-334.
- MAHESHWARI, S., MOHAN, J., CHAUHAN, D. S. Novel cascadable all-pass/notch filters using a single FDCCII and grounded capacitors. Circuits Syst. Signal Process., 2011, vol. 30, p. 643- 654.
- SIRIPRUCHYANUN, M., JAIKLA, W. Current controlled current conveyor transconductance amplifier (CCCCTA): a building block for analog signal processing. Electr. Eng., 2008, vol. 90, no. 6, p. 443-453.
- BHUSAN, M., NEWCOMB, R. W. Grounding of capacitors in integrated circuits. Electron. Lett., 1967, vol. 3, p. 148-149.
- SENANI, R., SINGH, V. K. KHN-equivalent biquad using current conveyors. Electron. Lett., 1995, vol. 31, p. 626-628.
- JANTAKUN, A., PISUTTHIPONG, N., SIRIPRUCHYANUN, M. A synthesis of temperature insensitive/electronically controllable floating simulators based on DV-CCTAs. In Proc. of ECTI-CON 2009. Pattaya (Thailand), 2009, p. 560-563.
- LAHIRI, A., JAIKLA, W., SIRIPRUCHYANUN, M. Voltagemode quadrature sinusoidal oscillator with current tunable properties. Analog Integr. Circ. Sig. Process., 2010, vol. 65, no. 2, p. 321-325.
- JAIKLA, W., SIRIPRUCHYANUN, M., LAHIRI, A. Resistorless dual-mode quadrature sinusoidal oscillator using a single active building block. Microelectron. J., 2011, vol. 42, no. 1, p. 135-140.
- PANDEY, N., PAUL, S. K. Analog filters based on 0.25 μm CMOS differential voltage current conveyor transconductance amplifier (DVCCTA). In Proc. of IICPE 2010. New Delhi (India), 2010, p. 1-5.
- PANDEY, N., PAUL, S. K. VM and CM universal filters based on single DVCCTA. Active and Passive Electronic Components, 2011, vol. 2011, Article ID 929507, 7 pages.
- HORNG, J. W. High input impedance voltage-mode universal biquadratic filter with three inputs using DDCCs. Circuits Syst. Signal Process., 2008, vol. 27, no. 4, p. 553-562.
- CHIU, W., LIU, S. I., TSAO, H. W., CHEN, J. J. CMOS differential difference current conveyors and their applications. IEE Proc. Circuits Devices Syst., 1996, vol. 143, no. 2, p. 91-96.
- BHASKAR, D. R., SINGH, A. K., SHARMA, R. K., SENANI, R. New OTA-C universal current-mode/trans-admittance biquads. IEICE Electronics Express, 2005, vol. 2, p. 8-13.
- WANG, Z. 2-MOSFET transistor with extremely low distortion for output reaching supply voltages. Electron. Lett., 1990, vol. 26, p. 951-952.
- FABRE, A., SAAID, O., BARTHELEMY, H. On the frequency limitations of the circuits based on second generation current conveyors. Analog Integr. Circ. Sig. Process., 1995, vol. 7, p. 113- 129.

Keywords: Differential Difference Current Conveyor Transconductance Amplifier (DDCCTA), universal filter, voltage-mode circuit

**N. Pandey, P. Kumar**
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Realization of Resistorless Wave Active Filter using Differential Voltage Current Controlled Conveyor Transconductance Amplifier

In this paper, a resistorless realization of high order voltage mode wave active filter based on Differential Voltage current controlled conveyor transconductance amplifier (DVCCCTA) is presented. The wave method is used for simulating reflected and incident wave for basic building block i.e. series inductor and configuring it for other passive element realization by making appropriate connection. The proposed structure uses grounded capacitors and possesses electronic tunability of cutoff frequency. The proposed approach is verified for a 4th order low pass filter through SPICE simulation using 0.25µm TSMC CMOS technology parameters.

- FERRI, G., GUERRINI, N. C. Low-Voltage Low-Power CMOS Current Conveyors. London: Kluwer Academic Publishers, 2003.
- GEIGER, R. L., SANCHEZ-SINENCIO, E. Active filter design using operational transconductance amplifiers: A tutorial. IEEE Circuits and Devices Magazine, 1985, vol. 1, p. 20 - 23.
- TOUMAZOU, C., PYNE A. Current feedback opamp: A blessing in disguise? IEEE Circuits and Devices Magazine, 1994, vol. 10, p. 43 - 47.
- SEDRA, A. S., SMITH, K. C. A second generation current conveyor and its application. IEEE Transactions on Circuit Theory, 1970, vol. 17, no. 1, p. 132 - 134.
- AWAD, I. A., SOLIMAN, A. M. Inverting second generation current conveyors: the missing building blocks, CMOS realizations and applications. International Journal of Electronics, 1999, vol. 86, no. 4, p. 413 - 432.
- FABRE, A., SAAID, O., WIEST, F., BOUCHERON, C. High frequency applications based on a new current controlled conveyor. IEEE Transactions on Circuit and Systems I, 1996, vol. 43, no. 2, p. 82 - 91.
- ELWAN, H. O., SOLIMAN, A. M. Novel CMOS differential voltage current conveyor and its applications. IEE Proceedings - Circuits Devices Systems, 1997, vol. 144, no. 3, p. 195 - 200.
- PROKOP, R., MUSIL, V. CCTA-a new modern circuit block and its internal realization. In Proceedings of International Conference on Electronic devices and systems IMAPSCZ’05. Brno (Czech Republic), 2005, p. 89 - 93.
- JAIKLA, W., SILAPAN, P., CHANAPROMMA, C., SIRIPRUCHYANUN, M. Practical Implementation of CCTA based on commercial CCII and OTA. In Proceedings of International Symposium on Intelligent Signal Processing and Communication Systems ISPACS 2008. Bangkok (Thailand), 2008, p. 1 - 4.
- SIRIPRUCHYANUN, M., JAIKLA, W. Current controlled current conveyor transconductance amplifier (CCCCTA): a building block for analog signal processing. Electrical Engineering, 2008, vol. 90, no. 6, p. 443 - 453.
- JANTAKUN, A., PISUTTHIPONG, N., SIRIPRUCHYANUN, M. A synthesis of temperature insensitive / electronically controllable floating simulators based on DV-CCTAs. In Proceedings of 6th International Conference on Electrical Engineering / Electronics, Computer, Telecommunications, and Information Technology ECTI-CON’09. Pattaya (Thailand), 2009, p. 560 - 563.
- JAIKLA, W., SIRIPRUCHYANUN, M., LAHIRI, A. Resistorless dual-mode quadrature sinusoidal oscillator using a single active building block. Microelectronics Journal, 2010, doi: 10.1016/j.mejo.2010.08.017
- IBRAHIM, M. A., MINAEI, S., KUNTMAN, H. A 22.5 MHz current-mode KHN-biquad using differential voltage current conveyor and grounded passive elements. International Journal of Electronics and Communication (AEU), 2005, vol. 59, no. 5, p. 311 - 318.
- HASSAN, T. M., SOLIMAN, A. M. New CMOS DVCC realization and applications to instrumentation amplifier and active-C filters. International Journal of Electronics and Communication (AEU), 2010, vol. 64, no. 1, p. 47 - 55.
- WUPPER, H., MEERKOTTER, K. New active filter synthesis based on scattering parameters. IEEE Transactions on Circuits and Systems, 1975, vol. 22, no. 7, p. 594 - 602.
- HARITANTIS, I., CONSTANTINIDES, A., DELIYANNIS, T. Wave active filters. IEE Proceedings, 1976, vol. 123, no. 7, p. 676 - 682.
- GEORGIA, K., COSTAS, P. Modular filter structures using CFOA. Radioengineering, 2010, vol. 19, no. 4, p. 662 - 666.
- ERDOGAN, E. S., TOPALOGLU, R. O., KUNTMAN, H., CICEKOGLU, O. New current mode special function continuous - time active filters employing only OTAs and OPAMPs. International Journal of Electronics, 2004, vol. 91, no. 6, p. 345 - 359.

Keywords: Differential voltage current controlled conveyor transconductance amplifier, wave Active Filter.

**P. Beg, I. A. Khan, S. Maheshwari, M. A. Siddiqi**
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Digitally Programmable Fully Differential Filter

In this paper a new digitally programmable voltage mode fully differential Kerwin-Huelsman-Newcomb(KHN) ﬁlter is realized using digitally controlled CMOS fully balanced output transconductor (DCBOTA). The realized ﬁlter uses ﬁve DCBOTAs, a single resistor and two capacitors. The ﬁlter provides low-pass, high-pass and band-pass responses simultaneously. The pole-frequency of all the responses is controlled by externally applying an 8- bit digital control word. All the responses exhibit independent digital control for pole-ω0 and pole-Q. The proposed ﬁlter also offers low passive sensitivities. Non-ideal gain and parasitic associated with the actual DCBOTA is also discussed. The CMMR results for low-pass response are also included which highlight the advantage of a fully-differential operation. Exhaustive PSPICE simulation is carried out using 0.5µ technology which may be further scaled to explore state-of-the-art applications of the proposed circuit.

- ALZAHER, H., ELWAN, H., ISMAIL, M. CMOS baseband filter for WCDMA integrated wireless receivers. Electronics Letters, 2000, vol. 38, no. 18, p. 1515 - 1516.
- IBRAHIM, A. M., KUNTMAN, H. A novel high CMRR high input impedance differential voltage-mode KHN-biquad employing DODDCCs. International Journal of Electronics (AEU), 2004, vol. 58, p. 429 - 433.
- EL-ADAWY, A. A., SOLIMAN, A. M., ELWAN, H. O. A novel fully differential current conveyor and applications for analog VLSI. IEEE Transactions on Circuits and Systems-II, 2000, vol. 47, no. 4, p. 306 - 313.
- AL-SHAHRANI, S. M. Fully differential second order filter. In Proceedings of the 47th IEEE International Midwest Symposium on Circuits and Systems (MWCAS). Hiroshima (Japan), 2004, vol. 3, p. 299 – 301.
- KAEWDANG, K., SURAKAMPONTOM, W. On the realization of electronically current-tunable CMOS OTA. International Journal of Electronics and Communications, 2007, vol. 61, p. 300 - 306.
- CHUNHUA, W., LING, Z., TAO, L. A new current OTA-C current mode biquad filter with single input and multiple outputs. International Journal of Electronics and Communications, 2008, vol. 62, p. 232 - 234.
- BIOLEK, D., BIOLKOVA, V., KOLKA, Z. Universal currentmode OTA-C KHN biquad. World Academy of Science, Engineering and Technology, 2007, vol. 31, p. 289 - 292.
- ZHANG, L., ZHANG, X., EL-MASRY, E. A highly linear bulkdriven CMOS OTA for continuous-time filters. Analog Integrated Circuits and Signal Processing, 2008, vol. 54, p. 229 - 236.
- SALAMA, K. N., SOLIMAN, A. M. Voltage-mode Kerwin- Huelsman-Newcomb circuit using CDBAs. Frequenz, 2000, vol. 54, p. 90 - 93.
- MAHESHWARI, S. Analog signal processing applications using a new circuit topology. IET Circuits, Devices and Systems, 2009, vol. 3, p. 106 -115.
- SALAMA, K. N., SOLIMAN, A. M. CMOS operational transresistance amplifier for analog signal processing. Microelectronics Journal, vol. 30, no. 3, 1999, p. 235 - 245.
- HASHIESH, M. A., MAHMOUD, S. A., SOLIMAN, A. M. Digitally controlled CMOS balanced output transconductor based on novel current-division network and its application. In Proceedings of the 47th IEEE International Midwest Symposium on Circuits and Systems (MWCAS). Hiroshima (Japan), 2004, vol. III, p. 323- 326.
- HASSAN, T. M., MAHMOUD, S. A. Low-voltage digitally programmable band-pass filter with independent controls. In Proceedings of the IEEE International Conference on Signal Processing and Communications (ICSPC 2007). Dubai (UAE), 2007, p. 24 -27.
- MAHMOUD, S. A., AWAD, I. A. New CMOS balanced output transconductor and application to Gm-C biquad filter. In Proceedings of the IEEE International Symposium on Circuits and Systems. Bangkok (Thailand), 2003, vol. 1, p. 385 - 388.
- TANGSRIRAT, W. Low-voltage digitally programmable current mode universal biquadratic filter. International Journal of Communication (AEU), 2008, vol. 62, p. 97 - 103.
- ALZAHER, H. A., TASADDUQ, N. A. A digitally programmable polyphase filter for Bluetooth. International Conference on Mixed Design of Integrated Circuits & Systems (MIXDES 2009). Warsaw (Poland), 2009, p.592 – 596.
- TANGSRIRAT, W., PRASERTSOM, D., SURKAMPONTORN, W. Low-voltage digitally controlled current differencing buffered amplifier and its application. International Journal of Electronics and Communication, 2009, vol. 63, p. 249 - 258.
- TSUKUTANI, T., HIGASHIMURA, M., TAKAHASHI, N., SUMI, Y., FUKUI, Y. Versatile voltage-mode active-only biquad with lossless and lossy integrator loop. International Journal of Electronic, 2001, vol. 88, p. 1093 - 1102.
- MAHESHWARI, S. High CMMR wide bandwidth instrumentation amplifier using controlled conveyors. International Journal of Electronics, 2002, vol. 89, no.12, p.889 - 896.
- CASAS, O., PALLAS-ARENY, R. Basics of analog di

Keywords: Fully differential, digital control, KHN filter

**V. Sebesta, R. Marsalek, Z. Fedra**
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OFDM Signal Detector Based on Cyclic Autocorrelation Function and its Properties

This paper is devoted to research of the general and particular properties of the OFDM signal detector based on the cyclic autocorrelation function. The cyclic autocorrelation function is estimated using DFT. The parameters of the testing signal have been chosen according to 802.11g WLAN. Some properties are described analytically; all events are examined via computer simulations. It is shown that the detector is able to detect an OFDM signal in the case of multipath propagation, inexact frequency synchronization and without time synchronization. The sensitivity of the detector could be decreased in the above cases. An important condition for proper value of the detector sampling interval was derived. Three types of the channels were studied and compared. Detection threshold SNR=-9 dB was found for the signal under consideration and for two-way propagation.

- QUAN, Z., et al. Collaborative wideband sensing for cognitive radios. IEEE Signal Processing Magazine, 2008, vol. 25, no. 6, p. 60-73.
- ERGEN, M. Mobile Broadband. Including WiMAX and LTE. New York: Springer, 2009.
- NOGUET, D., BIARD, L., LAUGEIOS, M. Cyclostationarity detectors for cognitive radio: Architectural tradeoffs [online]. Hindawi Publishing Corporation, EURASIP Journal on Wireless Communications and Networking, 2010 - [cit. 23-01-2011]. Available on www: http://www.hindawi.com/journals/wcn/2010/ 526429.html.
- ZHANG, H, LE RUYET, D., TERRE, M. Signal detection for OFDM/OQAM system using cyclostationary signatures. In IEEE 19th International Symposium on Personal, Indoor and Mobile Radio Communications. Cannes (France), 2008, p. 1-5.
- DANWATE, A. V., GIANNAKIS, G. B. Statistical tests for presence of cyclostationarity. IEEE Transactions on Signal Processing. 1994, vol. 42, no. 9, p. 2355-2369.
- SUN, Z., WANG, Q., CHE, CH. Study of cognitive radio spectrum detection in OFDM system. In Asia-Pacific Conference on Wearable Computing Systems. Shenzhen (China), 2010, p. 235- 238.
- AN, J., YANG, M., BU, X. Spectrum sensing for OFDM systems based on cyclostationary statistical test. In 6th International Conference on Wireless Communications Networking and Mobile Computing (WiCOM). Chengdu (China), 2010, p. 1 – 4.
- TURUNEN, V. et al. Implementation of cyclostationary feature detector for cognitive radios. In Proceedings of the 4th International Conference on CROWNCOM ‘09. Hannover (Germany), 2009, p. 1-4.
- KIM, M., KIMTHO, P., TAKADA, J.-i. Performance enhancement of cyclostationarity detector by utilizing multiple cyclic frequencies of OFDM signals. In IEEE Symposium on New Frontiers in Dynamic Spectrum, Singapore, 2010, p. 1-8.
- LUNDEN, J. et al. Spectrum sensing in cognitive radios based on multiple cyclic frequencies. In Proceedings of the 2nd Int. Conf. on Cognitive Radio Oriented Wireless Networks and Communications. Orlando (USA), 2007, p. 37-43.
- HARADA, H., FUJII, H., FURUNO, T., MIURA, S., OHYA, T. Iterative cyclostationarity-based feature detection of multiple primary signals for spectrum sharing scenarios. In IEEE Symposium on New Frontiers in Dynamic Spectrum. Singapore, 2010, p. 1-8.
- HAN, N., SOHN, S. H., KIM, J. M. Cyclic autocorrelation based blind OFDM detection and identification for cognitive radio. Journal of Communication and Computer [online]. May 2009, vol. 6, no. 5, [cit. March 17, 2011]. Available in www:
. ISSN 1548-7709. - MITRA, S. K. Digital Signal Processing. A Computer-Based Approach. The McGraw-Hill Companies, Inc., 1998.
- SEBESTA, V. Estimating a spectral correlation function under the conditions of imperfect relation between signal frequencies and a sampling frequency. Radioengineering, 2010, vol. 19, no. 1, p. 1- 5.
- SEBESTA, V. Estimating a spectral correlation function and its errors owing to inexact frequencies. In Proceedings of 20th International Conference RADIOELEKTRONIKA 2010. Brno (Czech Rep.), 2010. p. 129-132.
- LIEW, C. H., et al. Fixed and Mobile Channel Models Identifications [online]. SUIT_64, 2006. [cit. May 5, 2011]. Available on: http://suit.av.it.pt/dissemination/deliverables/SUIT_64_D2.1_chan nelmodel.pdf

Keywords: Spectrum sensing, cyclic autocorrelation function, OFDM, fading channel, frequency offset.

**B. Dimitrijevic, N. Milosevic, R. Marsalek, Z. Nikolic**
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BPSK Receiver Based on Recursive Adaptive Filter with Remodulation

This paper proposes a new binary phase shift keying (BPSK) signal receiver intended for reception under conditions of significant carrier frequency offsets. The recursive adaptive filter with least mean squares (LMS) adaptation is used. The proposed receiver has a constant, defining the balance between the recursive and the nonrecursive part of the filter, whose proper choice allows a simple construction of the receiver. The correct choice of this parameter could result in unitary length of the filter. The proposed receiver has performance very close to the performance of the BPSK receiver with perfect frequency synchronization, in a wide range of frequency offsets (plus/minus quarter of the signal bandwidth). The results obtained by the software simulation are confirmed by the experimental results measured on the receiver realized with the universal software radio peripheral (USRP), with the baseband signal processing at personal computer (PC).

- CLARKE, R. A statistical theory of mobile radio reception. Bell System Technical Journal, 1968, vol. 47, no. 6, p. 957-1000.
- HAJIAN, M., FERNANDES, J., CUNHA, P., LIGTHHART, P. Adaptive equalization for mobile communication systems based on constant modulus algorithm. In IEEE VTS 53rd Vehicular Technology Conference. Rhodes (Greece), 2001, vol. 3, p. 1609- 1613.
- TSIMENIDIS, C., HINTON, O., SHARIF, B., ADAMS, A. Linear predictor based method for estimating Doppler in mobile radio communication systems. Electronics Letters, 2000, vol. 36, no. 12, p. 1066-1067.
- KAM, P., CHUA, K., YU, X. Adaptive symbol-by-symbol reception of MPSK on Gaussian Channel with unknown phase characteristics. IEEE Trans. Commun., 1998, vol. 46, no. 10, p. 1275-1279.
- JUNG, J., HUANG, X. Phase error estimation and compensation for space-time coded communication systems. In IEEE International Conference on Communications, Circuits and Systems and West Sino Expositions. Sichuan (China), 2002, vol. 1, p. 511-515.
- BIN, L., HO, P. Data-aided phase tracking detection of Doppler shifted MPSK. Electronics Letters, 1996, vol. 32, no. 14, p. 1252- 1253.
- SHEEN, W., CHANG, M., WU, C. Performance analysis of noncoherent digital delay locked loops for direct sequence spread spectrum systems with Doppler shift and quantized adaptation. IEEE Trans. on Wireless Communications, 2004, vol. 3, no. 6, p. 2108-2118.
- KARKHANECHI, H., FAIN, E., LEVY, B. An investigation of carrier recovery techniques for space-time coded MIMO wireless systems. In IEEE Wireless Communications and Networking Conference 2002. Orlando (FL, USA), 2002, vol. 1, p. 454-458.
- FALCONER, D. Jointly adaptive equalization and carrier recovery in twodimensional digital communication systems. Bell Syst. Tech., 1976, p. 317-334.
- CUPO, R., GITLIN, R. Adaptive carrier recovery systems for digital data communications receivers. IEEE J. on Sel. Areas in Commun., 1989, vol. 7, no. 9, p. 1328-1339.
- SUGAR, G, TRETTER, S. Convergence properties of optimal adaptive carrier phase jitter predictors for sinusoidal jitter. IEEE Trans. Commun., 1995, vol. 43, no. 2/3/4, p. 225-228.
- NGUYEN, L. K., WELLS, R. B. Doppler shift cancellation using phasor and split phasor LMS algorithms. In IEEE Military Communications Conference 2008, MILCOM 2008. San Diego (CA, USA), 2008, p. 1-6.
- http://www.ettus.com/
- SLOCK, D. T. M. On the convergence behavior of the LMS and the normalized LMS algorithms. IEEE Transactions on Signal Processing, 1993, vol. 41, no. 9, p. 2811-2825.
- DOUGLAS, S. C. A family of normalized LMS algorithms. IEEE Signal Processing Letters, 1994, vol. 1, no. 3, p. 49-51.
- LEE, T. H. A 155-MHz clock recovery delay- and phase-locked loop. IEEE Journal of Solid-State Circuits, 1992, vol. 27, no. 12, p. 1736-1746.

Keywords: Binary Phase Shift Keying, adaptive signal processing, frequency offset compensation.

**P. Moravek, D. Komosny, M. Simek, D. Girbau, A. Lazaro**
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Energy Analysis of Received Signal Strength Localization in Wireless Sensor Networks

This paper presents the investigation of energy demands during localization of wireless nodes in ad-hoc networks. We focus on the method based on the received signal strength (RSS) to estimate the distances between the nodes. To deal with the uncertainty of this technique, statistical methods are used. It implies more measurement samples to be taken and consequently more energy to be spent. Therefore, we investigate the accuracy of localization and the consumed energy in the relation to the number of measurement samples. The experimental measurements were conducted with IRIS sensor motes and their results related to the proposed energy model. The results show that the expended energy is not related linearly to the localization error. First, improvement of the accuracy rises fast with more measurement samples. Then, adding more samples, the accuracy increase is moderate, which means that the marginal energy cost of the additional improvement is higher.

- DANESHGARAN, F., LADDOMADA, M., MONDIN, M. Problem of localization in networks of randomly deployed nodes: asymptotic and finite analysis, and thresholds. IET Communications, 2010, vol. 4, no. 8, p. 924 - 936.
- LIU, J., CHU, M., REICH, J. E. Multitarget tracking in distributed sensor setworks. IEEE Signal Processing Magazine, 2007, vol. 24, no. 3, p. 36 - 46.
- HU, L., EVANS, D. Localization for mobile sensor networks. In MobiCom ’04: Proceedings of the 10th Annual International Conference on Mobile Computing and Networking. New York (USA), 2004, p. 45 - 57.
- HSIEH, Y.,WANG, K., Efficient localization in mobile wireless sensor networks. In IEEE International Conference on Sensor Networks, Ubiquitous, and Trustworthy Computing. Taichung (Taiwan), 2006.
- LI, B., HOU, I. T., LIU, J., NGUYEN, G. D. Editorial: energy constraints and lifetime performance in wireless sensor networks. Mobile Networks and Applications, 2006, vol. 10, no. 6, p. 807-809.
- LIU, H., DARABI, H., BANERJEE, P., LIU, J. Survey of wireless indoor positioning techniques and systems. IEEE Transactions on Systems, Man, and Cybernetics, Part C: Applications and Reviews, 2007, vol. 37, no. 6, p. 1067 - 1080.
- LI, X. RSS-based location estimation with unknown pathloss model. IEEE Transactions on Wireless Communications, 2006, vol. 5, no. 12, p. 3626 - 3633.
- LIU, B., LIN, K., WU, J. Analysis of hyperbolic and circular positioning algorithms using stationary signal-strength difference measurements in wireless communications. IEEE Transactions on Vehicular Technology, 2006, vol. 55, no. 2, p. 499 - 509.
- BAHL, P., PADMANABLAN, V. N. RADAR: an inbuilding RFbased user location and tracking system. In 19th Annual Joint Conference of the IEEE Computer and Communications Societies INFOCOM 2000. Tel Aviv (Israel), 2000, vol. 2, p. 775 - 784.
- BULUSU, N., HEIDEMANN, J., ESTRIN, D. GPS-less low cost outdoor localization for very small devices. IEEE Personal Communications, 2000, vol. 7, no. 5, p. 28 - 34.
- YU, K., GUO, Y. J. Anchor-free localization algorithm and performance analysis in wireless sensor networks. IET Communications, 2009, vol. 3, no. 4, p. 549 - 560.
- JAKES, W. C. Microwave Mobile Communications. New York: Wiley, 1974. Reprinted by IEEE Press in 1994.
- KAY, S. M. Fundamentals of Statistical Signal Processing: Estimation Theory. Upper Saddle River (NJ, USA): Prentice Hall, 1993.
- MORAVEK, P., GIRBAU, D., LAZARO, A., KOMOSNY, D. Received signal strength uncertainty in energy-aware localization in wireless sensor networks. In 9th International Conference on Environment and Electrical Engineering EEEIC. Prague (Czech Republic), 2010, p. 538 - 541.
- STOYANOVA, T., KERASIOTIS, F.,PRAYATI, A., PAPADOPOULOS, G. A. Practical RF propagation model for wireless network sensors. In Third International Conference on Sensor Technologies and Applications SENSORCOMM ’09. Athens (Greece), 2009, p.194 - 199.
- HYUNGGI, CH., MYUNGSEOK, K., JONGHYUK, P., BYUNGSUNG, P., HAGBAE, K., Performance analysis of location estimation algorithm in ZigBee networks using received signal strength. In 21st International Conference on Advanced Information Networking and Applications Workshops AINAW ’07. Niagara Falls (USA), 2007, vol. 2, p. 302 - 306.
- LEE, J. S., SU, Y. W., SHEN, C. C. A comparative study of wireless protocols: Bluetooth, UWB, ZigBee, and Wi-Fi. In Proceedings of 33rd Annual Conference of the IEEE Industrial Electronics Society (IECON). Taipei (Taiwan), 2007, p. 46 - 51.
- CHAN, E., HAN, S. Energy efficient residual energy monitoring in wireless sensor networks. International Journal of Distributed Sensor Networks, 2009, vol. 5, no. 6, p. 748 - 770.
- TING, J., WEI, Z., CHENGLIN, Z., JIONG, S. An energy consumption optimized clustering algorithm for radar sensor networks based on an ant colony algorithm. EURASIP Journal on Wireless Communications and Networking, 2010.
- WATFA, M. K., SELMAN, S., DENKILKIAN, H. A battery-aware high-throughput MAC layer protocol in sensor networks. International Journal of Distributed Sensor Networks, 2010.
- POLLIN, S., ERGEN, M., ERGEN, S., BOUGARD, B., DER PERRE, L., MOERMAN, I., BAHAI, A., VARAIYA, P., CATTHOOR, F. Performance analysis of slotted carrier sense IEEE 802.15. 4 medium access layer. IEEE Transactions on Wireless Communication, 2008, vol. 7, no. 9, p. 3359 - 3371.
- KOHVAKKA, M., KUORILEHTO, M., HA¨ NNIKA¨ INEN, M., HA¨MA¨ LA¨ INEN, T. D. Performance analysis of IEEE 802.15.4 and ZigBee for large-scale wireless sensor network applications. In Proceedings of the 3rd ACM International Workshop on Performance Evaluation Of Wireless Ad Hoc, Sensor and Ubiquitous Networks PE-WASUN’2006. Torremolinos (Spain), 2006, p. 48 - 57.
- BOUGARD, B., CATTHOOR, F., DALY, D. C., CHANDRAKASAN, A., DEHAENE, W. Energy efficiency of the IEEE 802.15.4 standard in dense wireless microsensor networks: Modeling and improvement perspectives. In Proceedings of Design, Automation and Test in Europe DATE’05. Munich (Germany), 2005, p. 196 - 201.
- CASILARI, E., CANO-GARC´IA, J. M., CAMPOS-GARRIDO, G. Modeling of current consumption in 802.15.4/ZigBee sensor motes. Sensors, 2010, vol. 10, no. 6, p. 5443 - 5468.
- TERRASSON, G., BRIAND, R., BASROUR, S., DUPE, V., ARRIJURIA, O. Energy model for the design of ultra-low power nodes for wireless sensor networks. Procedia Chemistry, 2009, vol. 1, no. 1, p. 1195 - 1198.
- IEEE std. 802.15.4 - 2006: Wireless Medium Access Control (MAC) and Physical Layer (PHY) specifications for Low Rate Wireless Personal Area Networks (LR-WPANs). [Online] Available at: http://standards.ieee.org/getieee802/download/802.15.4-2006.pdf
- Crossbow IRIS (datasheet). [Online] Available at: http://www.xbow.com/Products/Product pdf files/Wireless pdf/ IRIS Datasheet.pdf
- Chipcon CC2420 (datasheet). [Online] Available at: http://enaweb.eng.yale.edu/drupal/system/files/ CC2420 Data Sheet 1 4.pdf

Keywords: Received signal strength, localization, localization error, energy consumption, RSS uncertainty, measurement, Wireless sensor network

**N. Ferdous, M. Ahmed, M. A. Matin, U. Habiba**
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Efficient Algorithm for Power Allocation in Relay-based Cognitive Radio Network

This paper addresses a cognitive radio (CR) network scenario where a relay is assigned to mitigate interference to primary users (PUs). We develop an average probability of successful secondary transmission (PSST) to introduce relay in the CR network. The power allocation is done using dual domain concept to maximize the system throughput as well as maintaining interference to an acceptable level and this approach is implemented in our paper that has a higher convergence rate. Furthermore, we propose an alternative approach that maintains a high throughput and at the same time reduces the computational complexity significantly. A detailed analysis is done before simulation. The simulated results validate the theoretical analysis.

- Federal Communications Commission. Spectrum Policy Task Force 1/8, an interleaver Report, ET Docket No. 02-155 Nov 02. 2002.
- HAYKIN, S. Cognitive radio: Brain-empowered wireless communications. IEEE Journal on Selected Areas in Communications, 2005, vol. 23, no. 2, p. 201 - 20.
- MITOLA, J., MAQUIRE, G. M. Cognitive radio: Making software radios more personal. IEEE Personal Communications, 1999, vol. 6, no. 4, p. 13 - 18.
- GANESAN, G., LI, Y. Agility improvement through cooperative diversity in cognitive radio networks. in IEEE Global Telecommunications Conference GLOBECOM 2005. St. Louis (USA), 2005, p. 2505 - 2509.
- ZHANG, Q., JIA, J., ZHANG, J. Cooperative relay to improve diversity in cognitive radio networks. IEEE Communications Magazine, 2009, vol. 47, no. 2, p. 111 - 117.
- JIA, J., ZHANG, J., ZHANG, Q. Cooperative relay for cognitive radio networks. in Proceedings IEEE INFOCOM. Rio de Janeiro (Brazil), 2009, p. 2304 - 2312.
- YAN, S., WANG, X. Power allocation for cognitive radio systems based on nonregenerative OFDM relay transmission. In 5th International Conference on Wireless Communications, Networking and Mobile Computing WiCom 2009. Beijing (China), 2009, p. 1-4.
- LIU, Z., XU, Y., ZHANG, D., GUAN, S. An efficient power allocation algorithm for relay assisted cognitive radio network. In International Conference on Wireless Communications and Signal Processing WCSP 2010. Suzhou (Cina), 2010, p. 1 - 5.
- OLFAT, M., FARROKHI, F. R., LIU, K. J. R. Power allocation for OFDM using adaptive beamforming over wireless networks. IEEE Transactions on Communications, 2005, vol. 53, no. 3, p. 505 - 514.
- IRWIN, M. E. Moment Generating Function.19 pages. [Online] Available at : http://www.markirwin.net/stat110/Lecture/ Section45.pdf .
- LI, L., ZHOU, X., XU, H., LI, G. Y., WANG, D., SOONG, A. Simplified relay selection and power allocation in cooperative cognitive radio systems. IEEE Transactions on Wireless Communications, 2011, vol. 10, no. 1, p. 33 - 36.
- CENDRILLON, R., MOONEN, M., YU, M., VERLINDEN, J., BOSTOEN, T. Optimal multiuser spectrum balancing for digital subscriber lines. IEEE. Transactions on Communications, 2006, vol. 54, no. 5, p. 922 - 933.
- BOYD, S., VANDENBERGHE, L. Convex Optimization. Cambridge University Press, 2004.
- YU, D. D., CIOFFI, J. M. Iterative water-filling for optimal resource allocation in OFDM multiple access and broadcast channels. In Proceedings of IEEE Global Telecommunications Conference Globecom 2006. San Francisco (CA, USA), 2006.

Keywords: Cooperative cognitive radio system, power allocation, dual domain, spectrum balancing algorithm, system throughput

**L. Polak, T. Kratochvil**
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Analysis and Simulation of the Transmission Distortions of the Mobile Digital Television DVB-SH Part 1: Terrestrial Mode DVB-SH-A with OFDM

This paper deals with the latest digital TV standard DVB-SH (Digital Video Broadcasting - Satellite to Handhelds) with focus on utilization of its advantages for the next generation of mobile TV broadcasting. The whole paper consists of two parts. In this first part, after the brief introduction to DVB-SH and related last works review, the simulation model of DVB-SH-A, which is using terrestrial configuration with OFDM transmission mode, is presented. The work is especially focused on the description of new type of forward error correction and system configuration of the DVB-SH-A mode. For the analysis and simulation of the transmission, the original scheme of turbo encoder was modified in this paper. Application for simulation of the transmission in mobile and portable fading transmission channels was developed in MATLAB. Dependences of BER on C/N ratio for all types of payload modulation are compared with focus on mobile TV services availability. Finally, the achieved results are evaluated and clearly discussed.

- FISHER, W. Digital Video and Audio Broadcasting. A Practical Engineering Guide. 2nd ed. Springer, 2008.
- KORNFELD, M., DAOUD, K. The DVB-H mobile Broadcast Standard. IEEE Signal Processing Magazine, 2008, p. 118-127.
- BORKO, F., SYED, A. Handbook of Mobile Broadcasting, DVBH, DMB, ISDB-T and MEDIAFLO. Taylor & Francis Group, LCC, 2008.
- ETSI TR 102 377 V1.4.1 (2009-06). Digital Video Broadcasting (DVB), DVB-H Implementation Guidelines. Technical recommendation. ETSI, 2009.
- ETSI TS 102 584 V1.2.1 (2011-01). Digital Video Broadcasting (DVB), DVB-SH Implementation Guidelines. Technical specification. ETSI, 2011.
- ETSI EN 302 583 V1.1.2 (2010-02). Digital Video Broadcasting (DVB), Framing Structure, channel coding and modulation for Satellite Services to Handheld devices (SH) below 3GHz. European standard. ETSI, 2008.
- WILKUS, S.A. and collective. Field measurements of a hybrid DVB-SH single frequency network with an inclined satellite orbit. IEEE Transaction on Broadcasting, 2010, vol. 56, no. 4, p. 523 to 531.
- COHEN, M., LE FLOCH, C., HANRIOT, J., WILKUS, S., POUSSET, G. DVB-SH field trials measurements results. In Proceedings of 11th Signal Processing for Space Communication Workshop (SPSC). Cagliari (Italy), 2010, p. 530-537.
- SADOUGH, S.M.S. Improved reception schemes for Digital Video Broadcasting based on hierarchical modulation. Radioengineering, 2011, vol. 20, no. 1, p. 159-166.
- SADOUGH, S.M.S., DUHAMEL, P. On the interaction between channel coding and hierarchical modulation. IEEE Communication Society. Dresden (Germany), 2009, p. 1-5.
- ISMAIL, M.A., TURLETTI, T., DABBOUS, W. Optimizing the DVB-SH FEC scheme for efficient erasure recovery. IEEE INFOCOM Workshop. Rio de Janeiro (Brazil) 2009, p. 1-6.
- PAPAHARALABOS, S., BENMAYOR, D., MATHIOPOULOS, P.T., FAN, P. Performance comparisons and improvements of channel coding techniques for Digital Satellite Broadcasting to mobile users. IEEE Transaction on Broadcasting, 2011, vol. 57, no. 1, p. 94-102.
- SMOLINKAR, M., JAVORNIK, T., MOHORIC, M., PAPAHARALABOS, S., MATHIOUPOULOS, P.T. Ratecompatible punctured DVB-S2 LDPC codes for DVB-SH applications. In International Workshop Satellite and Space Communications - IWSSC 2009. Siena (Italy), 2009, p. 13-17.
- HANZO, L., LIEW, T.H., YEAP, B.L. Turbo Coding, Turbo Equalisation and Space-Time Coding for Transmission over Fading Channels. John Wiley & Sons, Ltd., 2002.
- BENEDETTO, S., MONTORSI, G. Unveiling turbo codes: Some results on parallel concatenated coding schemes. IEEE Transactions on Information Theory, 1996, vol. 42, p. 409-428.
- HUTTL, O., KRATOCHVIL, T. DVB- SH forward error correction Implementation in Matlab. In Proceedings of the 18th Technical Computing Bratislava 2010. Bratislava (Slovakia), 2010, p. 41-46.
- DOLINAR, S., DIVSALAR, D. Weight distribution for turbo codes using random and nonrandom permutations. JPL TDA Progress Report 42-122, 1995, p. 56-65.
- SADJADPOUR, H.R., SLOANE, N.J.A., SALEHI, M., NEBE, G. Interleaver design for turbo codes. IEEE Journal on Selected Areas in Communications, 2001, vol. 19, no. 5, p. 831-837.
- STUKAVEC, R., KRATOCHVIL, T. Simulation of DVB-T transmission in Matlab. In Procedings of the 32nd International Convention on Information and Communication Technology, Electronics and Microelectronics MIPRO 2009. Rijeka (Croatia), 2009, p. 226-229.
- POLAK, L., KRATOCHVIL, T. DVB-SH digital television transmission and its simulation in MATLAB . In Procedings of the 21st International Conference Radioelektronika 2011. Brno (Czech Republic), 2011, p. 75-78.
- STUKAVEC, R., KRATOCHVIL, T. Simulation and measurement of the transmission distortions of the digital television DVB-T/H. Part 1: Modulator for digital terrestrial television. Radioengineering, 2010, vol. 19, no. 2, p. 338-346.
- STUKAVEC, R., KRATOCHVIL, T. Simulation and measurement of the transmission distortions of the digital television DVB-T/H. Part 2: Hierarchical modulation performance. Radioengineering, 2010, vol. 19, no. 3, p. 429-436.
- POLAK, L., KRATOCHVIL, T. Simulation and measurement of the transmission distortions of the digital television DVB-T/H. Part 3: Transmission in fading channels. Radioengineering, 2010, vol. 19, no. 4, p. 703-711.
- COST207, Digital Land Mobile Radio Communications (final report). Commission of the European Communities, Directorate General Telecommunications, Information Industries and Innovation, 1989.
- SR, D15, CP2-032, Services to Wireless, Integrated, Nomadic, GPRS-UMTS & TV Handheld Terminals, Wing TV, 2006.
- KRATOCHVIL, T. DVB-T/H Portable and Mobile TV Performance in the New Channel Profiles Modes. In Mehmood, R.; Cerqueira, E.; Piesiewicz, R.; Chlamtac, I. (Eds.): Communications Infrastructure, Systems and Applications., LNICST 160161, 2009. Lecture Notes of the Institute for Computer Sciences, Social- Informatics and Telecommunications Engineering (LNICST). London, UK: Springer, Institute for Computer Science, Social-Informatics and Telecommunications Engineering, 2009. p. 164-173.

Keywords: Digital television, mobile TV, DVB-SH-A, turbo coding, portable reception, mobile reception, BER

**K. B. Baltzis**
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A Simplified Geometric Channel Model for Mobile-to-Mobile Communications

In Mobile-to-Mobile (M2M) communications, the communicating nodes are surrounded by scatterers and equipped with low elevation antennas. This paper proposes a simple 2-D geometric scattering model for M2M channels. The model is also applicable in cellular systems when we employ low height base station antennas. In our approach, the scatterers are uniformly distributed in ellipses with arbitrary size and orientation around each communicating node. We provide simple formulas for the calculation of the angular spread and delay variation of the propagating signal. Simulation results verify the accuracy of the model. In order to validate the generalization of the approach, we compare it against notable models in the literature. As an application example, we investigate the impact of scatterer distribution and separation between mobiles on the angle and time of arrival statistics of the multipaths.

- WANG, C.-X., CHENG, X., LAURENSON, D. I. Vehicle-tovehicle channel modeling and measurements: Recent advances and future challenges. IEEE Communications Magazine, 2009, vol. 47, no. 11, p. 96 - 103.
- WIESER, V., PSENAK, V. Performance of advanced hybrid link adaptation algorithms in mobile radio channel. Radioengineering, 2008, vol. 17, no. 3, p. 81 - 86.
- BALTZIS, K. B. On the effect of channel impairments on VANETs performance. Radioengineering, 2010, vol. 19, no. 4, p. 689 - 694.
- BOBAN, M., VINHOZA, T. T. V., FERREIRA, M., BARROS, J., TONGUZ, O. K. Impact of vehicles as obstacles in vehicular ad hoc networks. IEEE Journal of Selected Areas in Communications, 2011, vol. 29, no. 1, p. 15 - 28.
- TALHA, B., PATZOLD, M. Channel models for mobile-to-mobile cooperative communication systems: A state of the art review. IEEE Vehicular Technology Magazine, 2011, vol. 6, no. 2, p. 33 to 43.
- MAURER, J., FUGEN, T., SCHAFER, T, WIESBECK, W. A new inter-vehicle communications (ivc) channel model. In Proceedings of the 60th IEEE Vehicular Technology Conference. Los Angeles (USA), 2004, vol. 1, p. 9 - 13.
- MAURER, J., FUGEN, T., WIESBECK, W. A ray-optical channel model for vehicular ad-hoc networks. In Proceedings of the 11th European Wireless Conference. Nicosia (Cyprus), 2005, p. 1 - 7.
- DIMITRIOU, A. G., BLETSAS, A., POLYCARPOU, A. C., SAHALOS, J. N. Theoretical findings and measurements on planning a UHF RFID system inside a room. Radioengineering, 2011, vol. 20, no. 2, p. 387 - 397.
- MALTSEV, A., MASLENNIKOV, R., LOMAYEV, A., SEVASTYANOV, A., KHORYAHEV, A. Statistical channel model for 60 GHz WLAN systems in conference room environment. Radioengineering, 2011, vol. 20, no. 2, p. 409 - 422.
- ACOSTA-MARUM, G., INGRAM, M. A. Six time- and frequency-selective empirical channel models for vehicular wireless LANs. IEEE Vehicular Technology Magazine, 2007, vol. 2, no. 4, p. 4 - 11.
- SEN, I., MATOLAK, D. W. Vehicle–vehicle channel models for the 5-GHz band. IEEE Transactions on Intelligent Transportation Systems, 2008, vol. 9, no. 2, p. 235 - 245.
- RENAUDIN, O., KOLMONEN, V.-M., VAINIKAINEN, P., OESTGES, C. Wideband measurement-based modeling of intervehicle channels in the 5 GHz band. In Proceedings of the 5th European Conference on Antennas and Propagation. Rome (Italy), 2011, p. 2881 - 2885.
- BALTZIS, K. B. Current issues and trends in wireless channel modeling and simulation. Recent Patents on Computer Science, 2009, vol. 2, no. 3, p. 166 - 177.
- CHENG, X., WANG, C.-X., YUAN, Y., LAURENSON, D. I., GE, X. A novel 3D regular-shaped geometry-based stochastic model for non-isotropic MIMO mobile-to-mobile channels. In Proceedings of the 72nd IEEE Vehicular Technology Conference. Ottawa (Canada), 2010, 5 pages, doi:10.1109/VETECF.2010. 5594351.
- PAUL, B. S., HASAN, A., MADHESHIYA, H., BHATTACHARJEE, R. Time and angle of arrival statistics of mobile-to-mobile communication channel employing circular scattering model. IETE Journal of Research, 2009, vol. 55, no. 6, p. 275 - 281.
- CHENG, X., WANG, C.-X., LAURENSON, D. I., SALOUS, S., VASILAKOS, A. V. An adaptive geometry-based stochastic model for non-isotropic MIMO mobile-to-mobile channels. IEEE Transactions on Wireless Communications, 2009, vol. 8, no. 9, p. 4824 - 4835.
- PAUL, B. S., BHATTACHARJEE, R. Time and angle of arrival statistics of mobile-to-mobile communication channel employing dual annular strip model. IETE Journal of Research, 2010, vol. 56, no. 6, p. 327 - 332.
- TALHA, B., PATZOLD, M. A geometrical three-ring-based model for MIMO mobile-to-mobile fading channels in cooperative networks. EURASIP Journal on Advances in Signal Processing, 2011, 13 pages, doi:10.1155/2011/892871.
- BALTZIS, K. B., SAHALOS, J. N. A simple 3-D geometric channel model for macrocell mobile communications. Wireless Personal Communications, 2009, vol. 51, no. 2, p. 329 - 347.
- PIECHOCKI, R. J., TSOULOS, G. V, McGEEHAN, J. P. Simple general formula for PDF of angle of arrival in large cell operational environments. Electronic Letters, 1998, vol. 34, no. 18, p. 1784 - 1785.
- ERTEL, R. B., REED, J. H. Angle and time of arrival statistics for circular and elliptical scattering models. IEEE Journal on Selected Areas in Communications, 1999, vol. 17, no. 11, p. 1829 - 1840.
- POLAK, L., KRATOCHVIL, T. Simulation and measurement of the transmission distortions of the digital television DVB-T/H. Part 3: Transmission in fading channels. Radioengineering, 2010, vol. 19, no. 4, p. 703 - 711.
- SIMSIM, M. T., KHAN, N. M., RAMER, R., RAPAJIC, P. B. Time of arrival statistics in cellular environments. In Proceedings of the 63rd IEEE Vehicular Technology Conference. Melbourne (Australia), 2006, p. 2666 - 2670.
- OLENKO, A. Y., WONG, K. T., NG, E. H.-O. Analytically derived TOA-DOA statistics of uplink/downlink wireless multipaths arisen from scatterers on a hollow-disc around the mobile. IEEE Antennas and Wireless Propagation Letters, 2003, vol. 2, p. 345 to 348.

Keywords: Angle of arrival, time of arrival, regular-shaped Geometrical-Based Stochastic Models, scattering, Mobile-to-Mobile channel.

**S. M. S. Sadough, M. Modarresi**
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A New Method For Increasing the Accuracy of EM-based Channel Estimation

It was recently shown that the detection performance can be significantly improved if the statistics of channel estimation errors are available and properly used at the receiver. Although in pilot-only channel estimation it is usually straightforward to characterize the statistics of channel estimation errors, this is not the case for the class of data-aided (semi-blind) channel estimation techniques. In this paper, we focus on the widely-used data-aided channel estimation techniques based on the expectation-maximization (EM) algorithm. This is achieved by a modified formulation of the EM algorithm which provides the receiver with the statistics of the estimation errors and properly using this additional information. Simulation results show that the proposed data-aided estimator outperform its classical counterparts in terms of accuracy, without requiring additional complexity at the receiver.

- CAVERS, J. K. An analysis of pilot symbol assisted modulation for Rayleigh fading channels. IEEE Transactions on Vehicular Technology, 1991, vol. 40, no. 4, p. 686 - 693.
- CIRPAN, H. A., PANAYIRCI, E., DOGAN, H. Non-data-aided channel estimation for OFDM systems with space-frequency transmit diversity. IEEE Transactions on Vehicular Technology, 2006, vol. 55, no. 2, p. 449 - 457.
- MA, X., KOBAYASHI, H., SCHWARTZ, S. C. EM-based channel estimation algorithms for OFDM. EURASIP Journal on Applied Signal Processing, 2004, vol. 10, p. 1460 - 1477.
- LU, B.,WANG, X., LI, Y. G. Iterative receivers for space-time block coded OFDM systems in dispersive fading channels. IEEE Transactions on Wireless Communications, 2002, vol. 1, no. 2, p. 213 - 225.
- CHRISTENSEN, L. P. B., LARSEN, J. On data and parameter estimation using the variational Bayesian EM-algorithm for blockfading frequency-selective MIMO channels. InProceedings of IEEE International Conference on Acoustics, Speech and Signal Processing ICASSP 2006. Toulouse (France), 2006, p. IV.
- LIN, D. D., LIM, T. J. A variational inference framework for soft-in soft-out detection in multiple-access channels. IEEE Transactions on Information Theory, 2009, vol. 55, no. 5, p. 2345 - 2363.
- STEFANATOS, S., KATSAGGELOS, A. K. Joint data detection and channel tracking for OFDM systems using the variational Bayes method. In Proceedings of the IEEE Signal Processing Advances in Wireless Communications SPAWC 2007. Helsinki (Finland), 2007, p. 1 - 5.
- SADOUGH, S. M. S., DUHAMEL, P. Improved iterative detection and achieved throughputs of OFDM systems under imperfect channel estimation. IEEE Transactions on Wireless Communications, 2008, vol. 7, no. 12., p. 5039 - 5050.
- SADOUGH, S. M. S., KHALIGHI, M. A., DUHAMEL, P. Improved iterative MIMO signal detection accounting for channel-estimation errors. IEEE Transactions on Vehicular Technology, 2009, vol. 58, no. 7, p. 3154 - 3167.
- SADOUGH, S. M. S. Robust iterative receiver design under imperfect channel estimation. In Proceedings of 6th IEEE Conference on Wireless Advanced WiAD 2010. London (UK), 2010, p. 1 - 5.
- SADOUGH, S., PIANTANIDA, P., DUHAMEL, P. MIMO-OFDM optimal decoding and achievable information rates under imperfect channel estimation. In 8th IEEE Workshop on Signal Processing Advances in Wireless Communications SPAWC 2007. Helsinki (Finland), 2007, p. 1 - 5.
- PRASAD, R. OFDM for Wireless Communications Systems. Boston: Artech House, 2004.
- MCLACHLAN, G. J., KRISHNAN, T. The EM Algorithm and Extensions. New York: Wiley, 1997.
- KULLBACK, S. Information Theory and Statistics New York: Wiley, 1959.
- BAHL, L., COCKE, J., JELINEK, F., RAVIV, J. Optimal decoding of linear codes for minimizing symbol error rate. IEEE Transactions on Information Theory, 1974, vol. 20, no. 2, p. 284 - 287.
- SCHARF, L. Statistical Signal Processing. Reading (MA, USA): Addison and Wesley, 1991.

Keywords: EM algorithm, VBEM algorithm, joint iterative data detection and channel estimation, characterizing channel estimation errors, OFDM.

**C. Gong, B. N. Zhang, A. J. Liu, D. X. Guo**
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A High Accurate and Low Bias SNR Estimator: Algorithm and Implementation

Signal to noise ratio (SNR) estimators are required for many radio engineering applications. In this paper, a SNR estimator based on the first and second order moments is derived and examined for constant envelop modulations over additive white Gaussian noise (AWGN) channel. In the first, a modification method is proposed to reduce the bias of conventional first and second order moments based SNR estimator. Then, in order to reduce hardware implementation complicity, multi segments of cubic polynomial are adopted to approximate the expression of the proposed SNR estimator which doesn’t have a close form solution. The approximate expression is very precise in the SNR range -10dB ~ 20 dB as illustrated by numerical simulation. Besides, practical hardware circuit is proposed for FPGA implementation. Simulation results show that the proposed SNR estimator has the lowest normalized bias and variance when compared with two other classic estimators.

- BENEDETTO, S. et al., High-speed ACM modem for satellite application. IEEE Wireless Communications, April 2005, p. 66-77.
- HANZO, L., WOODARD, P., ROBERTSON, P. Turbo decoding and detection for wireless applications. Proceedings of the IEEE, 2007, vol. 95, no. 6, p. 1178-200.
- BEAULIEU, N., TOMS, A., PAULUZZI, D. Comparison of four SNR estimators for QPSK modulation. IEEE Communication Letters, Feb. 2000, vol. 4, p.43–45.
- SUMMERS, A., WILSON, G. SNR mismatch and online estimation in turbo decoding IEEE Transactions on Communications, 1998, vol. 46, no. 4, p. 421-423.
- XU, H., ZHENG, H. The simple SNR estimator for MPSK signals. In Proc. IEE ICSP, vol. 2, p. 1781-1785
- BEAULIEU, N., TOMS, A., PAULUZZI, D. Comparison of four SNR estimators for QPSK modulation. IEEE Communication Letters, 2000, vol. 4, no. 2, p.43–45.
- LI, B., DIFAZIO, R., ZEIRA, A. A low bias algorithm to estimate negative SNRs in an AWGN channel. IEEE Communication Letters, 2002, vol. 6, no. 11, p. 469–471.
- REN, G., CHANG, Y., ZHANG H. A new SNR’s estimator for QPSK modulations in an AWGN channel. IEEE Transaction on Circuits and Systems—II: Express Briefs, 2005, vol. 52, no. 6, p. 336-338.
- BENEDICT, R., SOONG, T. The joint estimation of signal and noise from the sum envelope. IEEE Trans. Inform. Theory, 1967, vol. IT-13, p. 447–454.
- MATZNER, R., ENGLEBERGER, F. An SNR estimation algorithm using fourth-order moments. In Proc. IEEE Int. Symp. on Information Theory. Trondheim (Norway), 1994, p. 119.
- GAO, P., TEPEDELENLIOGLU, C. SNR estimation for nonconstant modulus constellations. IEEE Trans. Signal Processing, 2005, vol. 53, no. 3, p. 865-870.
- BAKKALI, M., STEPHENNE, A., AFFES, S. Iterative SNR estimation for MPSK modulation over AWGN channels. Vehicular Technology Conference. Montreal (Que), 2006, p. 1-5.
- LOPEZ-VALCARCE, R., MOSQUERA, C. Sixth-order statisticsbased nondata-aided SNR estimation. IEEE Communication Letters, 2007, vol. 11, no. 4, p.351-353.
- STEPHENNE, A., BELLILI, F., AFFES, S. Moment-based SNR estimation over linearly-modulated wireless SIMO channels. IEEE Transaction on Wireless Communications, 2010, vol. 9, no. 2, p. 714-722.
- PROAKIS, G. Digital Communications. 4th edition. New York: McGraw-Hill, 2001.
- KOTA, K., CALLARO, R. Numerical accuracy and hardware trade-offs for CORDIC arithmetic for special purpose processors. IEEE Transactions on Computers, 1993, vol. 42, no.7, p.769-779.

Keywords: SNR estimation, MPSK, moment based, curve fitting, FPGA

**M. Stanić, A. Lebl, D. Mitić, Z. Markov**
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Error Probability in Redundant Packet Sending over IP Network

In this paper we calculate error probability of packetized signal when method of redundant packet sending is used in IP network. The number of repeated signaling packets from each interval of packetization is determined to achieve the desired error probability. The method for management of this number of repetitions is developed based on the new analysis. This method is especially important in the case of sending signaling criteria of classic telephony network over IP network, because it makes possible to reach the same error probability as in classic telephony network.

- KYRCHBACHOV, B., BARONAK, I., KOVACIK, M., JANATA, V. Evaluation and investigation of the delay in VoIP networks. Radioengineering, 2011, vol. 20, no. 2, p. 540 - 547.
- SCHULZRINNE, H., TAYLOR, T. RFC 4733: RTP Payload for DTMF Digits, Telephony Tones, and Telephony Signals. December 2006.
- PERKINS, C., KOUVELAS, I., HODSON, O., HARDMAN, V., HANDLEY, M., BOLOT, J.C., VEGA-GARCIA, A., FOSSEPARISIS, S. RFC2198: RTP Payload for Redundant Audio Data., September 1997.
- HAY, R. IP Packet Overhead. [Online]. Available at: http://www.tamos.net/~rhay/overhead/ip-packet-overhead.htm.
- ITU-T. Recommendation G.107: The E-model: a computational model for use in transmission planning. April 2009.
- ITU-T. Recommendation Q.706: Specifications of signalling system No. 7: Message transfer part signalling performance. March 1993.
- FRIEDMAN, T., CACERES, R., CLARK, A. RFC3611: RTP Control Protocol Extended Reports (RTCP XR). November 2003.
- SCHULZRINNE, H., CASNER S., FREDERICK, R., JACOBSON, V. RFC3550: RTP: A Transport Protocol for Real- Time Applications. July 2003.

Keywords: IP network, error probability, redundant packet

**Y. Tang, R. Simerly, R. A. Moats**
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An Automatic Technique for MRI Based Murine Abdominal Fat Measurement

Because of the well-known relationship between obesity and high incidence of diseases, fat related research using mice models is being widely investigated in preclinical experiments. In the present study, we developed a technique to automatically measure mice abdominal adipose volume and determine the depot locations using Magnetic Resonance Imaging (MRI). Our technique includes an innovative method to detect fat tissues from MR images which not only utilizes the T1 weighted intensity information, but also takes advantage of the transverse relaxation time(T2) calculated from the multiple echo data. The technique contains both a fat optimized MRI imaging acquisition protocol that works well at 7T and a newly designed post processing methodology that can automatically accomplish the fat extraction and depot recognition without user intervention in the segmentation procedure. The post processing methodology has been integrated into easy-to-use software that we have made available via free download. The method was validated by comparing automated results with two independent manual analyses in 26 mice exhibiting different fat ratios from the obesity research project. The comparison confirms a close agreement between the results in total adipose tissue size and voxel-by-voxel overlaps.

- MANN, G. V. The influence of obesity in health. N Engl J Med, 1974, vol. 291, p.178–185.
- LARSSON, B., SVARDSUDD, K., WELIN, L., WILHELMSEN, L., BJORNTORP, P., TLIBBLIN, G. Abdominal adipose tissue distribution, obesity and risk of cardiovascular disease and death: 13 y follow up of participants in the study of men born in 1913. Br Med J Clin Res, 1984, vol. 288, p.1401-1404.
- BECHAH, Y., PADDOCK, C. D., CAPO, C., MEGE, J. L., RAOULT, D. Adipose tissue serves as a reservoir for recrudescent Rickettsia prowazekii infection in a mouse model. PLoS One , 2010, vol. 5, no. 1, e. 8547.
- CHURCH, C., LEE, S., BAGG, E. A., MCTAGGART, J. S., DEACON, R., GERKEN, T., LEE, A., MOIR, L., MECINOVIĆ, J., QUWAILID, M. M., SCHOFIELD, C. J., ASHCROFT, F. M., COX, R. D. A mouse model for the metabolic effects of the human fat mass and obesity associated FTO gene. PLoS Genet, 2009, vol. 5, no. 8, e. 1000599.
- RANEFALL, P., BIDAR, A. W., HOCKINGS, P. D. Automatric segmentation of intra-abdominal and subcutaneous adipose tissue in 3D whole Mouse MRI. J Magn Reson Imaging, 2009, vol. 30, no. 3, p. 554-560.
- SIEGEL, M. J., HILDEBOLT, C. F., BAE, K. T., CHENG, H., WHITE, N. H. Total and intraabdominal fat distribution in preadolescents and adolescents: Measurement with MR imaging. Radiology, 2007, vol. 242, no. 3, p. 846-856.
- CHAE, Y., JEONG, M. G., KIM, D. Three dimensional volume measurement of mice abdominal fat in magnetic resonance images. e-Health Networking, Application and Services, 2007, p. 252–255.
- POSITANO, V., GASTALDELLI, A., SIRONI, A. M., SANTARELLI, M. F., LOMBARDI, M., LANDINI, L. An accurate and robust method for unsupervised assessment of abdominal fat by MRI. J Magn Reson Imaging, 2004, vol. 20, no. 4, p. 684-689.
- POSITANO, V., CHRISTIANSEN, T., SANTARELLI, M. F., RINGGAARD, S., LANDINI, L., GASTALDELLI, A. Accurate segmentation of subcutaneous and intermuscular adipose tissue from MR images of thigh. J Magn Reson Imaging, 2009, vol. 29, p. 677-684.
- HOU, Z. A review on mr image intensity inhomogeneity correction. Int. J. Biomed. Imag, 2006, p.1-11.
- VOVK, U., PERNUS, F., LIKAR, B. A review of methods for correction of intensity inhomogeneity in MRI. IEEE Trans Med Imaging. 2007, vol. 26, p. 405–21.
- DIXON, W. T. Simple proton spectroscopic imaging. Radiology, 1984, vol. 153, p. 189-194.
- REEDER, S. B., PINEDA, A. R., WEN, Z., SHIMAKAWA, A., YU, H., BRITTAIN, J. H., GOLD, G. E., BEAULIEU, C. H., PELC, N. J. Iterative decomposition of water and fat with echo asymmetry and Least-Squares Estimation (IDEAL): Application with fast spin-echo imaging. Magnetic Resonance in Medicine, 2005, vol. 54, p. 636–644.
- PENG, Q., MCCOLL, R. W., WANG, J., CHIA, J. M., WEATHERALL, P. T. Water-saturated three-dimensional balanced steady-state free precession for fast abdominal fat quantification. J Magn Reson Imaging, 2005, vol. 21, p. 263–271.
- MANSON, J. E., COLDITZ, G. A., STAMPFER, M. J., WILLETT, W. C., ROSNER, B., MONSON, R. R., SPEIZER, F. E., HENNEKENS, C. H. A prospective study of obesity and risk of coronary heart disease in women. N Engl J Med, 1990, vol. 322, p. 882–889.
- LESLIE, W. D., LUDWIG, S. M., MORIN, S. Abdominal fat from spine dual-energy X-ray absorptiometry and risk for subsequent diabetes. J Clin Endocrinol Metab, 2010, vol. 95, no. 7, p. 3272- 3276.
- ZHAO, B., COLVILLE, J., KALAIGIAN, J., CURRAN, S., JIANG, L., KIJEWSKI, P., SCHWARTZ, L. H. Automated quantification of body fat distribution on volumetric computed tomography. J Comput Assist Tomogr, 2006, vol. 30, no. 5, p. 777 to 783.
- OHSHIMA, S., YAMAMOTO, S., YAMAJI, T., SUZUKI, M., MUTOH, M., IWASAKI, M., SASAZUKI, S., KOTERA, K., TSUGANE, S., MURAMATSU, Y. MORIYAMA, N. Development of an automated 3D segmentation program for volume quantification of body fat distribution using CT. Nippon Hoshasen Gijutsu Gakkai Zasshi, 2008, vol. 64, no. 9, p. 1177-1181.
- LUU, Y. K., LUBLINSKY, S., OZCIVICI, E., CAPILLA, E., PESSIN, J. E., RUBIN, C. T., JUDEX, S. In vivo quantification of subcutaneous and visceral adiposity by micro-computed tomography in a small animal model. Med Eng Phys, 2009, vol. 31, no. 1, p. 34-41.
- TOMASI, C., MANDUCHI, R. Bilateral filtering for gray and color images. Proc. Int. Conf. Computer Vision, 1998, p. 839-846.
- DUNN, J. C. A fuzzy relative of the ISODATA process and its use in detecting compact well-separated clusters. Journal of Cybernetics, 1973, vol. 3, p. 32-57.
- LIU, J., NIEMINEN, A., KOENIG, J. L. Calculation of T1, T2 and proton spin density in nuclear magnetic resonance imaging. Journal of Magnetic Resonance, 1998, vol. 85, p. 95-110.
- BONNY, J. M., ZANCA, M., BOIRE, J. Y., VEYRE, A. T2 maximum likelihood estimation from multiple spin-echo magnitude images. Magnetic Resonance in Medicine, 1996, vol. 36, p. 287-293.
- SIJBERS, J., DEN DEKKER, A. J., VERHOYE, M., RAMAN, E., VAN DYCK, D. Optimal estimation of T2 maps from magnitude MR images. Proc. SPIE Med. Imag., 1998, vol. 3338, p. 384.
- MARQUARDT, D.W. An algorithm for Least-Squares estimation of nonlinear parameters. Journal of the Society for Industrial and Applied Mathematics, 1963, vol. 11, p. 431-441.
- HENKELMANM, R. M. Measurement of signal intensities in the presence of noise in MR images. Med. Phys, 1985, vol. 12, p. 232 to 233.
- YOUSEM, D. M., IHMEIDA, I., QUENCER, R., ATLAS, S. W. Paradoxically decreased signal intensity on post contrast short-TR MR images. AJNR, 1991, vol. 12, p. 875-880.
- GONZALEZ, R. C., WOODS, R. E. Digital Image Processing. 2nd edition. Boston, MA: Addison-Wesley Longman Publishing, 1992.
- ZADEH, L. A. Fuzzy sets. Inform Contr, 1965, vol. 8, p. 338-353.
- CALDERAN, L., MARZOLA, P., NICOLATO, E., FABENE, P. F., MILANESE, C., BERNARDI, P., GIORDANO, A., CINTI, S., SBARBATI, A. In vivo phenotyping of ob/ob mouse by magnetic resonance imaging and H-Magnetic resonance spectroscopy. Obesity, 2006, vol. 14, p. 405–414.
- COX, E. The Fuzzy Systems Handbook: a Practitioner's Guide to Building, Using and Maintaining Fuzzy Systems. Academic Press, 1994.
- MINSKY, M. A framework for representing knowledge. In P.H.Winston(Ed), The Psychology of Computer Vision. New York: McGraw-Hill,1975.
- COLLINS, D. L., ZIJDENBOS, A. P., BAARE, WIM F. C., EVANS, A. C. Animal+Insect: Improved cortical structure segmentation. Lecture Notes in Computer Science, 1999, vol. 1613, p. 210-223.
- CALVIN, M., QI, R. S., RAGHAVAN, V. A Linear time algorithm for computing exact Euclidean distance transforms of binary images in arbitrary dimensions. IEEE Transactions on Pattern Analysis and Machine Intelligence, 2003, vol. 25, no. 2, p. 265-270.

Keywords: Measurement, MRI, abdominal, mice, FatExtractor.

**D. Schwarz, T. Kasparek**
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Comparison of Two Methods for Automatic Brain Morphometry Analysis

The methods of computational neuroanatomy are widely used; the data on their individual strengths and limitations from direct comparisons are, however, scarce. The aim of the present study was direct comparison of DBM based on high-resolution spatial transforms with widely used VBM analysis based on segmented high-resolution images. We performed DBM and VBM analyses on simulated volume changes in a set of 20 3-D MR images, compared to 30 MR images, where only random spatial transforms were introduced. The ability of the two methods to detect regions with the simulated volume changes was determined using overlay index together with the ground truth regions of the simulations; the precision of the detection in space was determined using the distance measures between the centers of detected and simulated regions. DBM was able to detect all the regions with simulated local volume changes with high spatial precision. On the other hand, VBM detected only changes in vicinity of the largest simulated change, with a poor overlap of the detected changes and the ground truth. Taken together we suggest that the analysis of high-resolution deformation fields is more convenient, sensitive, and precise than voxel-wise analysis of tissue-segmented images.

- ASHBURNER, J., HUTTON, C., FRACKOWIAK, R., JOHNSRUDE, I., PRICE, C., FRISTON, K. J. Identifying global anatomical differences: deformation-based morphometry. Hum Brain Mapp, 1998, vol. 6, p. 348 - 357.
- ASHBURNER, J., FRISTON, K. J. Voxel-based morphometry-- the methods. Neuroimage, 2000, vol. 11, p. 805 - 821.
- GIULIANI, N. R., CALHOUN, V. D., PEARLSON, G. D., FRANCIS, A., BUCHANAN, R. W. Voxel-based morphometry versus region of interest: a comparison of two methods for analyzing gray matter differences in schizophrenia. Schizophr Res, 2005, vol. 74, p. 135 - 147.
- GONG, Q. Y., SLUMING, V., MAYES, A., KELLER, S., BARRICK, T., CEZAYIRLI, E., ROBERTS, N. Voxel-based morphometry and stereology provide convergent evidence of the importance of medial prefrontal cortex for fluid intelligence in healthy adults. Neuroimage, 2005, vol. 25, p. 1175 - 1186.
- KELLER, S. S., MACKAY, C. E., BARRICK, T. R., WIESHMANN, U. C., HOWARD, M. A., ROBERTS, N. Voxel-based morphometric comparison of hippocampal and extrahippocampal abnormalities in patients with left and right hippocampal atrophy. Neuroimage, 2002, vol. 16, p. 23 - 31.
- MEHTA, S., GRABOWSKI, T. J., TRIVEDI, Y., DAMASIO, H. Evaluation of voxel-based morphometry for focal lesion detection in individuals. Neuroimage, 2003, vol. 20, p. 1438 - 1454.
- BOOKSTEIN, F. L. Voxel-based morphometry should not be used with imperfectly registered images. Neuroimage, 2001, vol. 14, p. 1454 - 1462.
- CORBO, V., CLEMENT, M. H., ARMONY, J. L., PRUESSNER, J. C., BRUNET, A. Size versus shape differences: contrasting voxel-based and volumetric analyses of the anterior cingulate cortex in individuals with acute posttraumatic stress disorder. Biol Psychiatry, 2005, vol. 58, p. 119 - 124.
- XIE, Z., FARIN, G. E. Image registration using hierarchical Bsplines. IEEE Trans Vis Comput Graph, 2004, vol. 10, p. 85 - 94.
- CSERNANSKY, J. G., WANG, L., JONES, D., RASTOGICRUZ, D., POSENER, J. A., HEYDEBRAND, G., MILLER, J. P., MILLER, M. I. Hippocampal deformities in schizophrenia characterized by high dimensional brain mapping. Am J Psychiatry, 2002, vol. 159, p. 2000 - 2006.
- GASER, C., NENADIC, I., BUCHSBAUM, B. R., HAZLETT, E. A., BUCHSBAUM, M. S. Deformation-based morphometry and its relation to conventional volumetry of brain lateral ventricles in MRI. Neuroimage, 2001, vol. 13, p. 1140 - 1145.
- SCHWARZ, D., KASPAREK, T., PROVAZNIK, I., JARKOVSKY, J. A deformable registration method for automated morphometry of MRI brain images in neuropsychiatric research. IEEE Trans Med Imaging, 2007, vol. 26, p. 452 - 461.
- KASPAREK, T., PRIKRYL, R., MIKL, M., SCHWARZ, D., CESKOVA, E., KRUPA, P. Prefrontal but not temporal grey matter changes in males with first-episode schizophrenia. Prog Neuropsychopharmacol Biol Psychiatry, 2007, vol. 31, p. 151 to 157.
- SLED, J. G., ZIJDENBOS, A. P., EVANS, A. C. A nonparametric method for automatic correction of intensity nonuniformity in MRI data. IEEE Trans Med Imaging, 1998, vol. 17, p. 87 - 97.
- COLLINS, D. L., NEELIN, P., PETERS, T. M., EVANS, A. C. Automatic 3D intersubject registration of MR volumetric data in standardized Talairach space. J Comput Assist Tomogr, 1994, vol. 18, p. 192 - 205.
- ROGELJ, P., KOVACIC, S. Spatial deformation models for nonrigid image registration. In Proceedings of the 9th Computer Vision Winter Workshop (CVWW’04). Piran (Slovenia), p. 79 - 88.
- ASHBURNER, J., FRISTON, K. J. Unified segmentation. Neuroimage, 2005, vol. 26, p. 839 - 851.
- CUADRA, M. B., CAMMOUN, L., BUTZ, T., CUISENAIRE, O., THIRAN, J. P. Comparison and validation of tissue modelization and statistical classification methods in T1-weighted MR brain images. IEEE Trans Med Imaging, 2005, vol. 24, p. 1548 - 1565.
- HONEA, R., CROW, T. J., PASSINGHAM, D., MACKAY, C. E. Regional deficits in brain volume in schizophrenia: a meta-analysis of voxel-based morphometry studies. Am J Psychiatry, 2005, vol. 162, p. 2233 - 2245.
- ELLISON-WRIGHT, I., GLAHN, D. C., LAIRD, A. R., THELEN, S. M., BULLMORE, E. The anatomy of first-episode and chronic schizophrenia: an anatomical likelihood estimation meta-analysis. American Journal of Psychiatry, 2008, vol. 165, p. 1015 - 1023.
- MEDA, S. A., GIULIANI, N. R., CALHOUN, V. D., JAGANNATHAN, K., SCHRETLEN, D. J., PULVER, A., CASCELLA, N., KESHAVAN, M., KATES, W., BUCHANAN, R., SHARMA, T., PEARLSON, G. D. A large scale (N=400) investigation of gray matter differences in schizophrenia using optimized voxel-based morphometry. Schizophr Res, 2008, vol. 101, p. 95 - 105.
- ASHBURNER, J. A fast diffeomorphic image registration algorithm. Neuroimage, 2007, vol. 38, p. 95 - 113.
- ROHLFING, T., MAURER, C. R., JR., BLUEMKE, D. A., JACOBS, M. A. Volume-preserving nonrigid registration of MR breast images using free-form deformation with an incompressibility constraint. IEEE Trans Med Imaging, 2003, vol. 22, p. 730 to 741.
- SHEN, D., DAVATZIKOS, C. Very high-resolution morphometry using mass-preserving deformations and HAMMER elastic registration. Neuroimage, 2003, vol. 18, p. 28 - 41.

Keywords: Image registration, voxel-based morphometry, deformation-based morphometry, simulated deformations, MRI.