Phase Noise Resilient Codebook Design for Sparse Code Multiple Access

TL;DR

This paper introduces a new codebook design for SCMA that enhances phase noise resilience, leading to better error rates in future communication systems with massive connectivity.

Contribution

It proposes a novel phase noise resilient codebook design using a new metric and a PAM-based constellation, improving error performance over existing codebooks.

Findings

Proposed codebooks have higher MPNM values.

Achieve improved error rate performance.

Outperform state-of-the-art codebooks.

Abstract

Sparse code multiple access (SCMA) is a promising technique for future machine type communication systems due to its superior spectral efficiency and capability for supporting massive connectivity. This paper proposes a novel class of sparse codebooks to improve the error rate performance of SCMA in the presence of phase noise (PN). Specifically, we first analyze the error rate performance of SCMA impaired by looking into the pair-wise error probability. Then, a novel codebook design metric, called minimum PN metric (MPNM), is proposed. In addition, to design PN resilient codebooks, we propose a novel pulse-amplitude modulation (PAM)-based low projection mother constellation (LP-MC), called LP-PAM. The codebooks for different users are obtained by rotating and scaling the MC, where the phase rotation angles and scaling factors for different users are optimized by maximizing the proposed MPNM. Numerical results show that the proposed PNCBs have larger MPNM values and achieve improved error rate performance than the-state-of-the-art codebooks.