Patent ID: 7363570

Claim:
A computer readable recording medium storing a program for implementing a method of converting a parity check matrix for low density parity check coding, the method comprising moving rows and columns of the parity check matrix such that elements of a diagonal line are filled with “1”, the elements of an upper block with respect to the diagonal line are filled with “0”, and the elements of a lower block with respect to the diagonal line contains at least one “1,”. wherein the moving the rows and columns comprises: moving columns linked with a first row in the parity check matrix to a left side of the parity check matrix; defining a submatrix including the columns linked with the first row and excluding the first row as a current search area, and a submatrix to the right of the current search area as a current complementary search area; selecting rows in which a number of 1's included in the current search area is equal to (row degree −1); moving an element positioned at an intersection of one of the selected rows and a column linked with the one of the selected rows, to an upper left corner of the current complementary search area through row movement and/or column movement of the one of the selected rows and the column linked with the one of the selected rows if a row is selected; updating the current search area to include the column moved during the moving of the element and to exclude the one of the selected rows, and updating the current complementary search area to be a submatrix positioned to the right of the updated current search area; performing iteratively the selecting of the rows through the updating of the current search area and the current complementary search area; and updating iteratively the current search area until a last row of the parity check matrix is reached.