determining a number Ns of columns corresponding to systematic bits in the base matrix and a number Nrow of rows of the base matrix according to a code rate of the permutation matrix;

determining a maximum row weight dc of the base matrix and a total weight range of the base matrix, wherein the row weight of each row in the base matrix is dc or dc−1;

according to the total weight range of the base matrix and the number Nrow of rows of the base matrix, determining a first range of rows with the row weights of dc−1 and a second range of rows with the row weights of dc in the base matrix;

according to the number Nrow of rows, the total weight range, the first range and the second range of the base matrix, filling the systematic bit part of each row in an initial base matrix corresponding to the base matrix to obtain an intermediate base matrix;

performing convergence calculation on the intermediate base matrix to determine whether the intermediate base matrix converges, and determining the intermediate base matrix as the base matrix in response to the intermediate base matrix converging;

generating the permutation matrix for QC-LDPC codes based on the base matrix;

encoding data to be transmitted based on the permutation matrix for QC-LDPC codes to generate QC-LDPC codes data; and

transmitting the generated QC-LDPC codes data to a decoding device through a channel.