Abstract
An adaptive maximum a posteriori (MAP) receiver withmultiple-access interference (MAI) mitigation is proposed for DS-CDMAsystems in frequency-flat, time-varying fading channels. The receiverconsists of a sequence matched filter (MF), an adaptive channelestimator, and a MAP demodulator. By oversampling the MF output, thereceiver can characterize the MAI symbol-by-symbol to suppress thestrong and time-varying MAI. Without any pilot insertion and apriori knowledge, the channel estimator can adapt to various fadingchannels using a general, model-based approach. For practicalimplementations, a reduction in complexity is introduced and is shownto have a negligible effect on both uncoded and decoded bit errorrates (BER's).
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Tsai, S., Gao, W. & Lehnert, J.S. Reduced Complexity Adaptive MAP Receiver for Frequency-Flat, Time-Varying CDMA Channels. Wireless Personal Communications 17, 45–64 (2001). https://doi.org/10.1023/A:1008913501552
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DOI: https://doi.org/10.1023/A:1008913501552