Sparse Superimposed Coding Based on Index Redefinition
Xuewan Zhang, Dalong Zhang · IEEE Communications Letters · 2023
Sparse superimposed coding (SSC) is a promising coding technique to achieve high reliability and low latency for short packet communications. To further improve its performance, an index redefinition-based SSC (IR-SSC) is proposed, in which the sparse vector can represent$N$index bit streams and$N$modulation bit streams. The index redefinition is introduced to avoid index collisions of$N$index bit streams. Meanwhile, constellation rotation-based constellations are adopted as modulation constellations for$N$modulation bit streams and as identification tags of these$N$index bit streams. Correspondingly, a constellation matching-based multipath matching pursuit decoder is designed to recover the order of these$N$index bit streams and to decode all transmitted bits. Simulation results show that the proposed IR-SSC scheme can improve both the reliability and latency performance, compared with conventional SSC schemes.