Multiple-Candidate Successive Interference Cancellation with Widely-Linear Processing for MAI and Jamming Suppression in DS-CDMA Systems

摘要

In this paper, we propose a widely-linear (WL) receiver structure formultiple access interference (MAI) and {jamming signal (JS)} suppression indirect-sequence code-division multiple-access (DS-CDMA) systems. A vector spaceprojection (VSP) scheme is also considered to cancel the {JS} before detectingthe desired signals. We develop a novel multiple-candidate successiveinterference cancellation (MC-SIC) scheme which processes two consecutive usersymbols at one time to process the unreliable estimates and a number ofselected points serve as the feedback candidates for interference cancellation,which is effective for alleviating the effect of error propagation in the SICalgorithm. Widely-linear signal processing is then used to enhance theperformance of the receiver in non-circular modulation scheme. By bringingtogether the techniques mentioned above, a novel interference suppressionscheme is proposed which combines the widely-linear multiple-candidate SIC(WL-MC-SIC) minimum mean-squared error (MMSE) algorithm with the VSP scheme tosuppress MAI and {JS} simultaneously. Simulations for binary phase shift keying(BPSK) modulation scenarios show that the proposed structure achieves a betterMAI suppression performance compared with previously reported SIC MMSEreceivers at lower complexity and a superior {JS} suppression performance.