Performance analysis of an adaptive decision-feedback receiver in asynchronous CDMA systems
نویسندگان
چکیده
Recently, the performance of several linear multiuser receivers including the matched filter receiver, the decorrelator receiver, and the MMSE receiver has been analyzed in CDMA systems with random sequences. Little work has been done for nonlinear decision feedback receiver. In this paper, we extend the results for linear multiuser receivers to an asynchronous CDMA system with an adaptive decision-feedback detector (DFD). The performance of the DFD using both deterministic sequences and random sequences is analyzed. With the assumption of perfect feedback (i.e., the receiver always makes correct decisions), the feedback part of the adaptive DFD can suppress the interference due to the previous symbols of all users completely and correspondingly the user capacity of the whole system increases greatly when compared with a system using the MMSE receiver.
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تاریخ انتشار 2002