Design of non-precoded protograph-based LDPC codes

A new family of protograph-based codes with no punctured variable nodes is presented. The codes are constructed by using differential evolution, partial brute force search, and the lengthening method introduced by Nguyen et al.. The protograph ensembles satisfy the linear minimum distance growth property and have the lowest iterative decoding thresholds yet reported in the literature among protograph codes without punctured variable nodes. Simulation results show that the new codes perform better than state-of-the-art protograph codes when the number of decoding iterations is small.