码率兼容的LDPC码在中继通信系统中的研究

In this paper, the progressive edge-growth (PEG) algorithmcan be used to construct low-density parity-check (LDPC)codes at finite code lengths with large girths through the establishmentof edges between variable and check nodes in an edge-by-edgemanner. In [1], the authors derived a class of LDPC codes forrelay communication systems by extending the full-diversity root-LDPC code. However, the submatrices of the parity-check matrixH corresponding to this code were constructed separately; thus, thegirth of H was not optimized. To solve this problem, this paper proposesa modified PEG algorithm for use in the design of large girthand full-diversity LDPC codes. Simulation results indicated thatthe LDPC codes constructed using the modified PEG algorithm exhibiteda more favorable frame error rate performance than didcodes proposed in [1] over block-fading channels.