Low density parity check (LDPC) code check matrix construction method and corresponding matrix multiply operation device

The present invention relates to a check matrix of the LDPC code construction method and a corresponding matrix multiplication device, the method comprising the steps of: determining a length of the codeword structure n × L, L cyclic permutation submatrix size, and a checksum code rate R the number of rows of the matrix m × L, of the base matrix Hb of size m × n, the parity check matrix H of size mL × nL; check matrix H determining the optimal degree distribution; a configured maximum girth base matrix Hb; selecting appropriate shift factor obtained extend into the base matrix Hb girth QC-LDPC code is maximized, to determine the entire check matrix shifting factor '1' is determined by the position of the elements in the base matrix Hb H. Matrix generating means comprises a check unit, an information sequence generating unit, division unit and the multiplication unit. The present invention enables to reduce coding complexity and the resulting error performance very close to the random structure of the LDPC code, so as to achieve at the same time reduce the complexity of the LDPC code.