Patent ID: 7191378

Claim:
A method of encoding, comprising: accessing memory storing information representing a structured parity check matrix of Low Density Parity Check (LDPC) codes, the information being organized in tabular form, wherein each row represents occurrences of one values within a first column of a group of columns of the parity check matrix, the rows correspond to groups of columns of the parity check matrix, wherein subsequent columns within each at the groups are derived according to a predetermined operation; and outputting an LDPC coded signal based on the stored information representing the parity check matrix, wherein the first information bit in the j th group of M information bits is accumulated in the j th parity bit accumulator if the i th entry in (jM) th column of the parity check matrix is 1, where i=0,1,2,3, . . .k ldpc /M−1, wherein the remaining (M−1) information bits m=jM+1, jM+2, jM+3, . . . (j+1)M−1 of the j th group is accumulated in the parity bit accumulators according to {x+m mod M×q}mod(n ldpc −k ldpc ), wherein x denotes the address of the parity bit accumulator corresponding to the first bit, jM, in the group, and q is a code rate dependent constant, wherein after all of the information bits are exhausted, operations, starting with i=l are performed according to p l =p i ⊕p i−1 , i=1,2, . . . ,n ldpc −k ldpc −1, wherein final content of p i , i=0,1, . . . ,n ldpc −k ldpc −1 is equal to the parity bit p i .