An adaptive decision-feed back multiuser detector using parallel interference cancellation for CDMA systems
Yung‐Fa Huang, Jyh‐Horng Wen, Hsien–Tsai Wu · 2002
The cancellation-weight in a partial parallel interference cancellation (PPIC) multiuser detector is unable to exhaustively show the correctness of the bit-decision in the previous stage for direct-sequence code-division multiple-access (DS-CDMA) communication systems. Therefore, in this study, we investigate the cancellation-weight property based on the adaptation of the least mean square (LMS) algorithm and propose an adaptive decision-threshold to judge the correctness of the bit-decision in the previous stage. Furthermore, the bit-inversion procedure is proposed to reverse the incorrect bit-decision and thereby an adaptive decision-feedback full PIC (DF-FPIC) detector is proposed to fulfill the multiuser detection for CDMA systems. Simulation results show that the proposed multistage DF-FPIC detector is highly near-far resistant.