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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: DS-CDMA Receiver Based on a Five-Port Technology Ivo Maljevi´ c | EURASIP Journal on Applied Signal Processing 2005 11 1628-1644 2005 Hindawi Publishing Corporation DS-CDMA Receiver Based on a Five-Port Technology Ivo Maljevic The Edward S. Rogers Sr. Department of Electrical and Computer Engineering University of Toronto Toronto ON Canada M5S 1A1 Email ivom@comm.utoronto.ca Elvino S. Sousa The Edward S. Rogers Sr. Department of Electrical and Computer Engineering University of Toronto Toronto ON Canada M5S 1A1 Email sousa@comm.utoronto.ca Received 29 February 2004 Revised 15 November 2004 High data rates low-power consumption and low complexity will be the most important parameters in the design of the nextgeneration mobile terminals. In this paper we are introducing a new paradigm in the design of direct sequence spread spectrum receiver by combining analog and digital signal processing. The main difference with respect to the conventional all-digital receiver design approach is that the proposed mixed analog digital processing results in a symbol rate sampling rather than the high-rate subchip sampling. Analog signal despreading is the key part of the proposed receiver solution which is based on a five-port device a passive RF square-law-type device. It is used to perform two important tasks at the same time namely the direct conversion and analog despreading. To achieve lower complexity the proposed receiver uses rectangular instead of pulse-matched despreading at the cost of only a small performance degradation. Also we propose a new noncoherent pseudonoise PN code tracking scheme based on error signal generated through the L1 norm. This results in comparable or even better PN code tracking performance than L2 norm circuitry using less complex hardware. Further we explore how this technology can be applied in the design of DS-CDMA RAKE receiver for mobile terminals. Depending on how the pilot signal is multiplexed we propose two types of RAKE receivers. It is shown that under Rayleigh fading channel such receiver structures
