Interference Reduction Technique in Multistage Multiuser Detector for DS-CDMA System

Authors: Lokesh Tharani, R.P.Yadav

Abstract:

This paper presents the results related to the interference reduction technique in multistage multiuser detector for asynchronous DS-CDMA system. To meet the real-time requirements for asynchronous multiuser detection, a bit streaming, cascade architecture is used. An asynchronous multiuser detection involves block-based computations and matrix inversions. The paper covers iterative-based suboptimal schemes that have been studied to decrease the computational complexity, eliminate the need for matrix inversions, decreases the execution time, reduces the memory requirements and uses joint estimation and detection process that gives better performance than the independent parameter estimation method. The stages of the iteration use cascaded and bits processed in a streaming fashion. The simulation has been carried out for asynchronous DS-CDMA system by varying one parameter, i.e., number of users. The simulation result exhibits that system gives optimum bit error rate (BER) at 3rd stage for 15-users.

Keywords: Multi-user detection (MUD), multiple accessinterference (MAI), near-far effect, decision feedback detector, successive interference cancellation detector (SIC) and parallelinterference cancellation (PIC) detector.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1076818

References:

[1] Lokesh Tharani and Dr. R.P.Yadav, "Performance evaluation of multistage multiuser detector for asynchronous DS-CDMA system" IEEE Proceeding of International Conference on Computational Intelligence and Multimedia Applications 2007 (ICCIMA-07), Volume IV, page No. 316-321, Sivakasi, Tamilnadu, India,Dec 2007
[2] Andrew J. Viterbi, "CDMA Principles of Spread Spectrum Communication", Addison Wesley Longman, ISBN: 0201-63374-4.
[3] Sergio Verdu, "Multi-user detection", Cambridge University Press. ISBN: 0521-59373-5.
[4] Duel-Hallen, J. Holtzman, and Z. Zvonar, "Multi-user detection for CDMA systems,". IEEE Personal Communications Magazine, April 1995.
[5] Louis G.F. Trichard, " Optimal Multistage Linear Multiuser Receivers", IEEE Transaction on Wireless Communication, Vol. 4,NO. 3, May 2005
[6] S. Moshavi, "Multi-user detection for DS-CDMA communications--, IEEE communications magazine, Vol. 34, No. 10, page no. 124-136, October, 1996.
[7] H. V. Poor, S. Verdu, "Single-user detectors for multiuser channels," IEEE Trans. Comm. Vol. 36, no. 1, pp. 50-60, Jan. 1988.
[8] R. Lupas, S. Verdu, "Near-far resistance of multiuser detectors in asynchronous channels," , IEEE Trans. Comm. Vol. 38, no. 4, pp. 496- 508, April 1990.
[9] Tan F. Wong: "Spread spectrum & CDMA". www.wireless.ece.ufl.edu/twong/Notes/CDMA/ch6.pdf.
[10] John G. Prokis, "Digital communication", forth edition, McGraw-Hill International, 2001.
[11] Zartash Afzal Uzmi, "Simplified multiuser detection for CDMA systems", Ph.D., Thesis, September, 2002
[12] H.Y.Wu and A. Duel-Hallen," Performance comparison of multiuser detectors with channel estimation for flat rayleigh fading CDMA channels," Wireless Pres. Communication., July/august 1996
[13] Shridhar Rajgopal, Shrikrishna Bhashyam, Joseph R. Cavallaro and Behnaam Aazhang, "Real-Time Algorithms and Architectures for Multiuser Channel Estimation and Detection in Wireless Base Station Receivers", IEEE Transactions on Wireless Communications, Vol. 1, No. 3, July 2002.
[14] R..Michael Buehrer, Neiyer S. Correal-Mendoza and Brain D. Woerner," A simulation comparison of multiuser receivers for cellular CDMA", IEEE Transactions on Vehicular Technology, Vol. 49, No. 4, July, 2000.
[15] Lokesh Tharani and Dr. R.P. Yadav, "Non- Linear suboptimal multiuser detectors for DS-CDMA systems", Proceedings of International conference on soft computing and Intelligent System (ICSCIS-07), Jabalpur Engineering College, Jabalpur(M.P.), Vol. 3, page NO. 176- 180, December, 2007.
[16] Cottatellucci, Laura;Debbah, Merouane;Muller, Ralph R, "Linear multiuser detection for CDMA systems with correlated spatial diversity", ISCCSP 2006, IEEE 2nd International Symposium on Communications, Control and Signal Processing, 13-15 March 2006, Marrakech, Morocco.
[17] Cottatellucci, Laura;Debbah, Merouane;M├╝ller, Ralf R, "Asymptotic design and analysis of multistage detectors for asynchronous CDMA systems", ISIT 2004, IEEE International Symposium on Information Theory, June 27 - July 2, 2004, Chicago, USA , pp 509- 509.
[18] Seung Hee Han and Jae Hong Lee, "Multi-stage partial PIC receivers for multi_rate DS-CDMA system with multiple modulation," in Proc. of the IEEE WCNC 2003, pp. 591-594, Mar. 2003.
[19] Jerome M. Shapiro and James Dunyak, "Soft Information in Interference Cancellation Based Multiuser Detection", submitted for IEEE transaction on Wireless Communication, July 2005.
[20] Stephen J. Chapman, "MATLAB Programming for Engineering", Second Edition, Thomson Publication.
[21] A. Rajeswari, K.Gunavathi and A.Shanmugam,"A Selective Survey on Multiuser Detection Techniques in CDMA Systems", Academic Open Internet Journal, Volume 13, 2004.
[22] Halil Tanyer Eyyuboglu,"MATLAB Simulation of Multiuser Detection in CDMA", Proceeding of World Academy of Science, Engineering and Technology, volume 3, January 2005.