Constructing PCGCs with unequal-code-rate irregular component LDPC codes is proposed in this paper. Parameters of component codes are optimized by differential evolution based on EXIT chart. In the optimization results, code rate of component code 1 is relatively higher and the other one is lower so that these two component codes play different roles in different decoding stages. Numerical simulation results show that the proposed PCGCs with optimized parameters outperform PCGCs constructed by equal-code-rate regular/likely regular component codes and optimized irregular LDPC code.
['Fang Wang', 'Shixin Cheng', 'Wei Xu', 'Haifeng Wang']
Design and Code Optimization of Parallel Concatenated Gallager Codes