International Joint Conference on Information and Communication Engineering (JCICE)

Optimization of Root-Protograph LDPC Codes for Joint Source Channel Coding System over Block Fading Channel

Jihua Wu, Mengyao Wang, Qiwang Chen, Chen Chen

Published May 1, 2023• 1 citation

Abstract

Double protograph low-density parity-check (DP-LDPC) codes based on the joint source channel coding (JSCC) system has been demonstrated to have outstanding error performance over additive white Gaussian noise (AWGN) channels. However, because of the non-ergodic nature of the block-fading (BF) channels, the protograph low-density parity-check (PLDPC) codes cannot perform well over BF channel. Whereby the excellent error performance of root protograph LDPC (RPLDPC) codes under BF channel, we utilize RPLDPC codes for channel coding in DP_LDPC systems over BF channels. Then, we design a modified joint protograph extrinsic information transfer (JPEXIT) algorithm to calculate the decoding threshold of this system. utilizing the modified JPEXIT algorithm, to improve the error performance of the system. The traditional root protograph LDPC (RPLDPC) code for this system has been redesigned. The research results display that the systems with improved RPLDPC codes have lower decoding thresholds and faster convergence trend than existing RPLDPC codes and PLDPC codes.

DOI: 10.1109/jcice59059.2023.00021

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