Soft decision feedback receiver for CDMA communication in multipath

Multipath fading in wireless code division multiple access (CDMA) systems worsens the effects of multiple access interference and also leads to the near-far problem. To improve the performance of the detector based on the bank of correlators, in this paper, a post processing structure is proposed for synchronous CDMA systems observed in multipath. The proposed receiver consists of conventional correlator detectors and matrix filters that feedback previous decisions. To minimize the error propagation phenomenon in the decision feedback receiver, a soft decision mapping is proposed. The performance of the proposed receiver structure with the soft decisions is studied via simulations.

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