Method and apparatus for efficient data decoding

A digital data decoder for efficiently decoding codewords, comprising:

• a memory for storing processor-executable instructions, a plurality of temporary storage bins, and a low-density parity check (LDPC) H matrix, the LDPC H matrix comprising a plurality of zero and non-zero circulants arranged in a plurality of rows and columns;
• a plurality of decoding logics for decoding the codewords using circulants stored in the LDPC H matrix;
• and
• a processor coupled to the memory for executing the processor-executable instructions that causes the digital data decoder to:
• evaluate the LDPC H matrix in a first row ordering sequence, wherein each of the rows is evaluated one row at a time in an order prescribed by the first row ordering sequence;
• determine, for the first row ordering sequence, a first total number of column assignment mismatches;
• evaluate the LDPC H matrix in a second row ordering sequence, wherein each of the rows is evaluated one row at a time in a second order prescribed by the second row ordering sequence;
• determine, for the second row ordering sequence, a second total number of column assignment mismatches;
• assign the columns of the LDPC H matrix to the plurality of decoding logics based on the first row ordering sequence when the first total number of column assignment mismatches is less than the second total number of column assignment mismatches;
• and
• assign the columns of the LDPC H matrix to the plurality of decoding logics based on the second row ordering sequence when the second total number of column assignment mismatches is less than the first total number of column assignment mismatches.

A method, performed by a digital data decoder comprising n decoding logics, for efficiently decoding codewords, comprising:

• (a) ordering rows of a low-density parity check (LDPC) H matrix in a first particular order;
• (b) evaluating each row of the LDPC H matrix in sequence as defined by the ordering to assign columns of the LDPC H matrix to a set of n temporary storage bins, and to determine a mismatch in the assignment of columns to the set of n temporary storage bins;
• (c) repeating steps (a) and (b) a plurality of times, each time assigning columns of the LDPC H matrix to a different set of n temporary storage bins;
• (d) determining which ordering of the rows resulted in a fewest number of mismatches;
• and
• (e) assigning columns in the set of n temporary storage bins corresponding to the fewest number of mismatches to the n decoding logics.