Noisy Index Coding with Quadrature Amplitude Modulation (QAM)

TL;DR

This paper introduces a novel method for mapping index coded bits to M-QAM symbols in noisy Gaussian broadcast channels, enhancing decoding performance for receivers with specific side information conditions.

Contribution

It proposes a new QAM-based mapping technique for index coding, providing coding gain improvements over existing PSK-based methods in noisy channels.

Findings

QAM mapping yields coding gain for certain receivers

Comparison shows QAM outperforms PSK in specific scenarios

Method enhances robustness of index coding in noisy environments

Abstract

This paper discusses noisy index coding problem over Gaussian broadcast channel. We propose a technique for mapping the index coded bits to M-QAM symbols such that the receivers whose side information satisfies certain conditions get coding gain, which we call the QAM side information coding gain. We compare this with the PSK side information coding gain, which was discussed in "Index Coded PSK Modulation," arXiv:1356200, [cs.IT] 19 September 2015.