روشي جديد براي ساخت كدهايي با ماتريس پريتي - چك كم - چگالي

A New Construction Method for Low-Density Parity-Check Codes

Low-Density Parity-Check (LDPC) codes were introduced by Gallager in 1962. After more than three decades the near Shannon limit performance of these codes rediscovered by MacKay and Neal in 1996. Currently, LDPC code is one of the hot topics for research. In spite of simple iterative decoding for these codes by Sum-Product Algorithms (SPA), encoding and constructing of these codes have major difficulty. There exist a variety of methods for constructing LDPC codes. In this paper, we present and compare the most important of these methods. In addition we introduce a new constructing method to enhance the error performance.