FIG. 5A shows a code rate 1/2 LDPC parity check matrix H=336 rows×672 columns, with Z=42. FIG. 5B shows a code rate 5/8 LDPC parity check matrix H=252 rows×672 columns, with Z=42. FIG. 5C shows a code rate 3/4 LDPC parity check matrix H=168 rows×672 columns, with Z=42. FIG. 5D shows a code rate 13/16 LDPC parity check matrix H=126 rows×672 columns, with Z=42. In FIGS. 5A-5D, the blank entries represent Z×Z submatrices with all zero entries.
LDPC Codes with Codeword Length 1344 in 802.11ay
FIGS. 6A-6D illustrate four LDPC codes proposed in 802.11ay with the rates of 13/16, 3/4, 5/8 and 1/2. The code rate K/N denotes that a K bits source word is encoded to an N bits codeword. With respect to the 802.11ay standard, the codeword length N is 1344 bits. Therefore, for the code rates of 13/16, 3/4, 5/8 and 1/2, the sizes of the corresponding source word are 1092, 1008, 840 and 672 bits, respectively.
The LDPC codes illustrated in FIGS. 6A-6D are generated by two-step lifting. In the example of FIG. 6A, the rate 13/16 LDPC code 606 with codeword length of 1344 is generated from a lifting matrix 602 and the rate 13/16 base matrix 604 of 802.11ad with the lifting factor Z=42, as shown in FIG. 5D. In other words, the base matrix 604 has 126 rows×672 columns, Z=42, or 3 rows×16 columns of submatrices.
As shown in FIG. 6A, the lifting matrix 602 has the same rows and columns of submatrices as the rate 13/16 base matrix 604 of 802.11ad.
