Efficient coding method based on quasi-cyclic low density parity check (LDPC) code

Abstract

The invention provides an efficient coding method based on a quasi-cyclic low density parity check (LDPC) code. The method comprises a first step of obtaining an offset matrix B, wherein the number of rows of the offset matrix is 32, the number of columns of the offset matrix is 64, and element value is -1, 0, 1, 2...,63, each column of the offset matrix B is provided with three elements not being -1, each column is provided with five or six or seven elements not being -1, and the condition that in the offset matrix B, none of elements a, b, c and d is -1 in any 2*2 submatrix is nonexistent, or the condition that none of elements a, b, c and d is -1 is existent, but the a, b, c and d cannot fit a formula; a second step of constructing a parity check matrix H according to the offset matrix B, namely, replacing each element in the matrix B as a null matrix with size being 64*64 or a circular permutation matrix (CPM); a third step of conducting gaussian elimination on the H to form a system form Hsys; and a fourth step of encoding 2048 bit information m to be transmitted according to the system form Hsys. According to the efficient coding method based on the quasi-cyclic LDPC code, requirements to storage space are lowered, and good error correction performance can be well achieved in a decoding process.

Description

technical field [0001] The invention belongs to the technical field of information theory and coding, and in particular relates to a high-efficiency coding method based on a quasi-cyclic low-density parity-check (LDPC) code. Background technique [0002] As we all know, LDPC codes are very suitable for aerospace communication tasks, and its quasi-cyclic structure greatly reduces the requirements for hardware. See Song, Shumei, Bo Zhou, Shu Lin, and Khaled Abdel-Ghaffar."A unified approach to the construction of binary and nonbinary quasi-cyclic LDPC codes based on finite fields."Communications, IEEE Transactions on57, no.1(2009 ):84-93. The key to the quasi-cyclic LDPC code design is the design of the parity check matrix H. Not only the generation of the coding matrix G depends on H, but also the code rate and decoding performance of the designed LDPC code are directly determined by H. However, since the encoding matrix requires a large amount of storage resources, its sto...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to overcome the defects of the prior art, in order to solve the problem of large storage capacity when using quasi-cyclic LDPC codes in aerospace communications, the present invention improves the parity check matrix H in the quasi-cyclic LDPC codes, and proposes An Efficient Coding Method Based on Quasi-Cyclic LDPC Codes

Images