Joint Component Design for the JSCC System Based on DP-LDPC Codes
Sanya Liu, Lin Wang, Jun Chen, Shaohua Hong · IEEE Transactions on Communications · 2020
The joint base matrix BJof the joint source-channel coding (JSCC) system based on double protograph low-density parity-check (DP-LDPC) codes consists of four components, namely, the source code Bs, the channel code Bc, the type1 connection edge BL1and the type-2 connection edge BL2, each having a non-negligible influence on the system performance. Different from the traditional component-specific design approach, we propose a joint design and optimization algorithm based on the idea of multi-objective differential evolution (MODE). Specifically, we consider the optimization of the DP-LDPC JSCC system through joint design of three components Bs, Bc, BL1and all four components Bs, Bc, BL1, BL2, respectively. The proposed algorithm has low search complexity due to the reduction in size and element value of base matrices. The joint protograph extrinsic information transfer (JPEXIT) analyses and the simulation results demonstrate that the resulting JSCC system is free from a high error floor, requires fewer number of iterations for reaching the same bit error rate (BER) and achieves significant coding gains as compared to the state-of-the-art. Our DP-LDPC JSCC system is also shown to outperform its separation-based counterpart by a wide margin.