基于原模图LDPC码的分布式联合信源信道编码

Protograph LDPC Based Distributed Joint Source Channel Coding

该文提出一种基于原模图低密度奇偶校验(P-LDPC)码的分布式联合信源信道编译码系统方案。该方案编码端,分布式信源发送部分信息位及校验位以同时实现压缩及纠错功能;译码端,联合迭代信源信道译码的运用进一步发掘信源的相关性以获得额外的编码增益。此外,论文研究了所提方案在译码端未知相关性系数的译码算法。仿真结果表明,所提出的基于P-LDPC码的分布式联合信源信道编译码方案在外部迭代次数不大的情况可以获得较大的性能增益,并且相关性系数在译码端已知和未知系统性能基本相当。

This paper proposes a Distributed Joint Source-Channel Coding（DJSCC） scheme using Protograph Low Density Parity Check（P-LDPC） code. In the proposed scheme, the distributed source encoder sends some information bits together with the parity bits to simultaneously achieve both distributed compression and channel error correction. Iterative joint decoding is introduced to further exploit the source correlation. Moreover, the proposed scheme is investigated when the correlation between sources is not known at the decoder. Simulation results indicate that the proposed DJSCC scheme can obtain relatively large additional coding gains at a relatively small number of global iterations, and the performance for unknown correlated sources is almost the same as that for known correlated sources since correlation can be estimated jointly with the iterative decoding process.