Method and device for generating code rate compatible with low density parity check (LDPC) codes and hybrid automatic repeat request (HARQ) schemes

Abstract

The invention relates to the technical field of mobile communication channel coding, in particular to a method and a device for generating code rate compatible with quasi-cyclic low density parity check (LDPC) codes. The method comprises the following steps that: the degree distribution of high-code-rate quasi-cyclic LDPC codes and the low-code-rate requirement of a system are obtained, and the degree distribution of low-code-rate quasi-cyclic LDPC codes is designed; variable nodes to be expanded and check nodes to be resolved in the high-code-rate quasi-cyclic LDPC codes in the low-code-rate quasi-cyclic LDPC code constructing process are determined; check matrixes of the low-code-rate quasi-cyclic LDPC codes are constructed on the basis of a constructing method and the limitation of the low-code-rate quasi-cyclic LDPC codes on the check matrix check part structure; and the check bits of the obtained quasi-cyclic LDPC codes are interwoven, and then, code rate compatible codes are obtained through residue deletion. The embodiment of the invention also provides the device for implementing the method and provides hybrid automatic repeat request (HARQ) schemes based on the code rate compatible quasi-cyclic LDPC codes.

Description

technical field [0001] The invention relates to the technical field of channel coding for mobile communication, in particular to a method and device for generating code rate compatible LDPC codes and HARQ schemes. Background technique [0002] Low density parity check (LDPC, low density parity check) code is a linear block code proposed by Gallager in 1962. Because of the small number of "1" in its parity check matrix, it is called low density parity check The checksum was then reintroduced and improved upon by Mackay in 1996. In addition to expressing LDPC codes with parity check matrices, Tanner graphs can also be used (see figure 1 ) represents an LDPC code, and the Tanner graph corresponds directly to the check matrix, which consists of variable nodes, check nodes and edges connecting them. Each check node z i Corresponding to a row of check matrix, each variable node x i Corresponds to a column of the parity check matrix. When a certain bit in the codeword is inclu...

AI Technical Summary

Problems solved by technology

The degrees of the variable nodes corresponding to the high code rate quasi-cyclic LDPC codes in the low code rate quasi-cyclic LDPC code obtained by the above method cannot be flexibly adjusted, and the performance of the code needs to be optimized

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