Patent ID: 8489955
Filing Date: 2013-07-16
Classification: H03M,H04L

Abstract:
1. A data processing apparatus, comprising: re-arrangement means for carrying out, where code bits of an LDPC (Low Density Parity Check) code are written in a column direction of storage means for storing the code bits of the LDPC code in a row direction and the column direction and read out in the row direction are set as a symbol whereas m code bits equal to or more than 2 bits of the LDPC code are transmitted as one symbol, column twist interleave of changing the writing starting position when the code bits of the LDPC code are to be written in the column direction of said storage means for each column of said storage means as a re-arrangement process for re-arranging the code bits of the LDPC code; said storage means storing, where the code length of the LDPC code is represented as N bits, a predetermined positive integer as b and a minimum integer equal to or greater than N/(mb) as B, mb bits in the row direction and B bits in the column direction; when mb bits read out in the row direction of said storage means are set as b symbols, the LDPC code being any of LDPC codes which are prescribed in the DVB-S.2 or DVB-T.2 standard and have 11 different encoding rates and a code length N of 64,800 bits; the m bits being 14 bits while the integer b is 1; the 14 code bits of the LDPC code being mapped to ones of 2 said storage means having 14 columns for storing 14×1 bits in the row direction; said re-arrangement means setting, where the address of the top position of said storage means in the column direction is 0 and the addresses of the positions of said storage means in the column direction are represented by integers of an ascending order, the writing starting position for the first column from among the 14 columns of said storage means to the position whose address is 0, the writing starting position for the second column from among the 14 columns of said storage means to the position whose address is 2, the writing starting position for the third column from among the 14 columns of said storage means to the position whose address is 4, the writing starting position for the fourth column from among the 14 columns of said storage means to the position whose address is 5, the writing starting position for the fifth column from among the 14 columns of said storage means to the position whose address is 5, the writing starting position for the sixth column from among the 14 columns of said storage means to the position whose address is 6, the writing starting position for the seventh column from among the 14 columns of said storage means to the position whose address is 11, the writing starting position for the eighth column from among the 14 columns of said storage means to the position whose address is 14, the writing starting position for the ninth column from among the 14 columns of said storage means to the position whose address is 14, the writing starting position for the tenth column from among the 14 columns of said storage means to the position whose address is 14, the writing starting position for the eleventh column from among the 14 columns of said storage means to the position whose address is 14, the writing starting position for the twelfth column from among the 14 columns of said storage means to the position whose address is 19, the writing starting position for the thirteenth column from among the 14 columns of said storage means to the position whose address is 23, and the writing starting position for the fourteenth column from among the 14 columns of said storage means to the position whose address is 24.