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

TL;DR

This paper introduces a novel widely-linear multiple-candidate SIC receiver with vector space projection for effective suppression of multiple access interference and jamming in DS-CDMA systems, improving performance and reducing complexity.

Contribution

It proposes a new interference suppression scheme combining widely-linear processing, multiple-candidate SIC, and vector space projection for enhanced MAI and jamming suppression in DS-CDMA.

Findings

Achieves better MAI suppression than previous SIC MMSE receivers.

Provides superior jamming signal suppression.

Operates at lower complexity.

Abstract

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