A graphical model and search algorithm based Quasi-Cyclic Low-Density Parity-Check codes scheme

Abstract

A constant challenge in Quasi-Cyclic Low-Density Parity-Check (QC-LDP-C) codes lies on flexible code lengths and rates, conditioned by good error performance. This paper presents an optimal construction method of QC-LDPC codes on the basis of graphical model and search algorithm. Utilizing the proposed scheme, we can construct adaptable QC-LDPC codes whose girths are no less than 12, and column weights are 3. Comparing with any other QC-LDPC code construction approach, this method is much more flexible in block length and block rate. Furthermore, when construction parameters are selected, regular QC-LDPC codes can be constructed easily. Simulation results indicate that LDPC codes proposed in the method perform similarly to the classic Progressive Edge-Growth (PEG) based LDPC codes but outweigh in convenience of implementation and applications. © 2013 ICIC International.