A Method for Constructing Quasi-Cycle Extension LDPC Codes with Low Encoding Complexity
Wei Li · Electronics Optics & Control · 2012
Progressive-Edge-Growth(PEG) algorithm is an efficient method for constructing LDPC codes with short and intermediate block lengths.However,the complexity of codes produced directly by this algorithm is proportional to quadratic length of the codes,which restricts the implementation of the LDPC codes.To solve the problem,a method was proposed for constructing quasi-cycle extension LDPC codes with low encoding complexity and good error performance.Based on PEG algorithm,a base matrix with an approximate lower triangular was constructed,then all its elements were replaced by circulation permutations.The new method could eliminate the short cycles effectively without changing the degree distribution fraction of the basic matrix.The simulation results show that: compared with LDPC codes generated by PEG algorithm,the LDPC codes presented here have lower encoding complexity and better error performance,which is easy for implementation with hardware.