construction of irregular ldpc codes with low error …：与低误差的不规则ldpc码的构造….pdf

Construction of Irregular LD PC Codes with Low Error Floors Huanlin Li, Weizheng Huang and Jeffrey C. Dill Department of Electrical Engi neering puter Science Ohio University Athens, OH 45701, USA ABSTRACT This work describes a ne w systematic construction approach for irregular low-density par ity-check codes based on the splitting-and-filling technique. The generated code using this proposed method not only has a gi ven degree distribution pair but also has girth of at least si x. More importantly, by carefully filling the elements of the variable (check) node sets during the generating process, we can optimize one of the special combinatorial characteristics, such as the stopping size or the girth, of an LDPC code. Simulation results show that the resulting code can achieve good near capacity pe rformance as well as good error-floor performance when decoded using the iterative belief propagation (BP) decoding method. Keywords : Belief Propagation (BP); Irregular Low-Density Parity-Check (LDPC) Codes; Degree Distribution; Euclidean Geometry. 1. INTRODUCTION Low-density parity check (LDPC) codes, originally proposed by Gallager in 1962 in [1], have re-attracted researchers’ interest recently in coding theory because of their near capacity performance [2] and their parallel and plexity decoders. With the help of density e volution algorithm,