Improved quasi-cyclic LDPC codes based on Euclidean geometry

This paper presents an improved Euclidean geometry (EG) method for constructing parity check matrix of quasi-cyclic low-density parity-check (QC-LDPC) codes to decrease the performance degradation of short cycles to the iterative decoding. The new method results in a class of QC-LDPC codes with much fewer short cycles than usual EG-LDPC codes with the same parameters. Simulation results show that the designed QC-LDPC codes with fewer short cycles perform better than the existing Euclidean geometry LDPC codes under iterative decoding.