Encoding method and device for low density generator matrix codes

Abstract

The present invention discloses an encoding method and device for Low Density Generator Matrix Codes (LDGC). Wherein, the method comprises: construct an LDGC mother code set using a plurality of LDGC with code rate Rand different code lengths, wherein the LDGC mother code set has a uniform base matrix G={(g)}; obtain length L of an intermediate variable according to a relationship between length K of an information bit sequence to be encoded in the LDGC mother code set and length L of the intermediate variable; obtain an expanding factor z for processing the base matrix using the length of the intermediate variable and the number of rows in the base matrix; process the base matrix using the expanding factor to obtain a binary generator matrix Gtmp, the front L rows and front L columns of which compose a triangular matrix; modify the binary generator matrix to obtain a modified binary generator matrix; take a matrix Gcomposed of L rows and the front N+L−K columns of the modified binary generator matrix as a generator matrix of the information bit sequence to encode the information bit sequence.