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arXiv · 2205.08121

Design of Joint Source-Channel Codes Based on a Generic Protograph

Jia Zhan·Francis C. M. Lau
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Abstract

In this paper, we propose using a generic protograph to design joint source-channel codes (JSCCs). We present a generalized algorithm, called protograph extrinsic information transfer for JSCC algorithm (PEXIT-JSCC algorithm), for analyzing the channel threshold of the proposed JSCC. We also propose a source generic protograph EXIT (SGP-EXIT) algorithm, which is more appropriate than the generalized source protograph extrinsic information transfer (GSP-EXIT) algorithm, for evaluating the source threshold of a generic protograph. Moreover, a collaborative optimization method based on the SGP-EXIT and PEXIT-JSCC algorithms is proposed to construct generic-protograph JSCCs with good source and channel thresholds. Finally, we construct generic-protograph JSCCs, analyze their decoding thresholds, and compare their theoretical and error performance with JSCC systems based on optimized double-protographs. Results show that our proposed codes can attain channel thresholds within 1 dB from the Shannon limit and outperform double-protograph-based JSCCs.

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Jia Zhan, Francis C. M. Lau. 2022-05-17. Design of Joint Source-Channel Codes Based on a Generic Protograph. https://arxiv.org/abs/2205.08121

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