Method for generating low density parity check (LDPC) code

Abstract

The invention discloses a method for generating a low density parity check (LDPC) code. The method comprises the following steps of: reading circle length g and column weight k for a check matrix, and judging whether g / 2 is not more than 12; building a full mother matrix with k x k if g / 2 is not more than 12; searching effective cyclic shift parameters of each cyclic shift matrix and orders L of each cyclic shift matrix corresponding to each nonzero element in the mother matrix to acquire the cycle shift matrix corresponding to each effective cyclic shift parameter, wherein the cycle shift matrixes corresponding to zero elements in the mother matrix are zero matrixes, the orders are L; acquiring a sparse matrix H according to the cycle shift matrixes, wherein the circle length of the sparse matrix is g / 2; acquiring a Tanner pattern of the sparse matrix H; building a sparse check matrix H* through the Tanner pattern, wherein the column weight is 2, and the row weight is k; generating the LDPC code according to the acquired sparse check matrix H*, wherein the circle length is g, the column weight is 2, and the row weight is k. The LDPC code is small in column weight, and is long in circle length, so that the correction performance of a channel is improved.

Description

Technical field [0001] The invention belongs to the field of communication channel coding and decoding, and more specifically, relates to a method for generating LDPC codes. Background technique [0002] In actual applications, the channel is not ideal. There are various noises and other interferences, which damage the signal to be transmitted and cause errors in the received signal. Therefore, in order to ensure the accuracy of transmission, the information is usually Some redundant bits are added to the sequence to suppress interference, and the method of introducing redundant bits into the information bits is called channel coding. [0003] In channel coding, Low Density Parity Check (LDPC) is a linear block code approaching Shannon’s limit. It was proposed by Gallager in 1962. Due to the limitation of the calculation conditions at that time, it was not taken seriously. . With the development of computer technology, in 1995, Mackay and Neal perfected the LDPC code. However, f...

AI Technical Summary

Problems solved by technology

However, for traditional LDPC codes, the larger the column weight, the better the performance, but with the increase of the column weight, it will inevitably lead to the appearance of short loops, thereby reducing the error correction performance of the channel

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