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Báo cáo hóa học: " Two-Stage Maximum Likelihood Estimation (TSMLE) for MT-CDMA Signals in the Indoor Environment"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Two-Stage Maximum Likelihood Estimation (TSMLE) for MT-CDMA Signals in the Indoor Environment | EURASIP Journal on Wireless Communications and Networking 2004 1 55-66 2004 Hindawi Publishing Corporation Two-Stage Maximum Likelihood Estimation TSMLE for MT-CDMA Signals in the Indoor Environment Quazi Mehbubar Rahman Department of Electrical Computer Engineering Queen s University Kingston ON Canada K7L3N6 Email rahman@post.queensu.ca Abu B. Sesay Department of Electrical Computer Engineering University of Calgary AB Canada T2N1N4 Email sesay@enel.ucalgary.ca Mostafa Hefnawi Department of Electrical Computer Engineering Royal Military College of Canada ON Canada K7K 7B4 Email hefnawi-m@rmc.ca Received 31 October 2003 Revised 15 March 2004 This paper proposes a two-stage maximum likelihood estimation TSMLE technique suited for multitone code division multiple access MT-CDMA system. Here an analytical framework is presented in the indoor environment for determining the average bit error rate BER of the system over Rayleigh and Ricean fading channels. The analytical model is derived for quadrature phase shift keying QPSK modulation technique by taking into account the number of tones signal bandwidth BW bit rate and transmission power. Numerical results are presented to validate the analysis and to justify the approximations made therein. Moreover these results are shown to agree completely with those obtained by simulation. Keywords and phrases code division multiple access indoor fading channel OFDM maximum likelihood estimation. 1. INTRODUCTION High-data-rate multimedia communications is one of the challenges currently being addressed in the research domain for the upcoming next generation wireless systems 1 2 . Although the third generation 3G systems www.3gtoday.com are supporting a maximum data rate of 153 kbps CDMA2000 and 384 kbps WCDMA for voice and data applications and 2.4 Mbps for data-only CDMA 2000 1xEV-DO applications transmission rate for combined voice and data applications for the future generation systems is expected and needed to be much .