Method and apparatus for low density parity check encoding of data

Apparatus for low-density parity-check (LDPC) encoding of data, the apparatus comprising:

• matrix definition logic for defining a first M×N parity check, H=[H1] [H2];
• a triangular matrix generator for generating a second parity check matrix based on the first parity check matrix the second parity check matrix having an M×M triangular sub-matrix by replacing [H1] with a triangular matrix;
• and,
• an encoder for mapping the data into an LDPC code word based on the second parity check matrix.

A computer program product for low-density parity-check (LDPC) encoding of data, the computer program product comprising a machine readable storage medium storing computer program code which, when loaded in a programmable data processor, configures the processor to perform the steps of:

• defining a first M×N parity check matrix, H=[H1] [H2];
• generating, based on the first parity check matrix, a second parity check matrix having an M×M triangular sub-matrix by replacing [H1] with a triangular matrix;
• and,
• mapping the data into an LDPC code word based on the second parity check matrix.

A data transmitter for transmitting data received from an information source via a communications channel, the data being encoded by the transmitter into a low-density parity-check (LDPC) code word, the transmitter comprising:

• matrix definition logic for defining a first M×N parity check matrix, H=[H1] [H2];
• a triangular matrix generator for generating a second parity check matrix based on the first parity check matrix;
• the second parity check matrix having an M×M triangular sub-matrix by replacing [H1] with a triangular matrix;
• and, an encoder for mapping the data into an LDPC code word based on the second parity check matrix.

A data storage system for storing data received from an information source in a data storage channel, the data being encoded by the system into a low-density parity-check (LDPC) code word, the system comprising:

• matrix definition logic for defining a first M×N parity check matrix, H=[H1] [H2];
• a triangular matrix generator for generating a second parity check matrix based on the first parity check matrix;
• the second parity check matrix having an M×M triangular sub-matrix by replacing [H1] with a triangular matrix;
• and, an encoder for mapping the data into an LDPG code word based on the second parity check matrix.

A method for low-density parity-check (LDPC) encoding of data, the method comprising the steps of:

• defining a matrix H;
• generating a matrix HS by cyclically shifting the rows of matrix H until the leftmost subblock of HS contains the identity matrix I along its diagonal;
• triangularizing HS by replacing with zeroes all elements below the identity matrix I along the diagonal;
• and
• mapping the data into an LDPC code word based on the triangularized HS .

Apparatus for low-density parity-check (LDPC) encoding of data comprising:

• a matrix definition component for defining a matrix H;
• a matrix generating component for generating a matrix HS by cyclically shifting the rows of matrix H until the leftmost subblock of HS contains the identity matrix I along its diagonal and for triangularizing HS by replacing with zeroes all elements below the identity matrix I along the diagonal;
• and
• an encoder for mapping the data into an LDPC code word based on the triangularized HS .

A computer program product for low-density parity-check (LDPC) encoding of data, the computer program product comprising a machine readable storage medium storing computer program code which, when loaded in a programmable data processor, configures the processor to perform low-density parity-check (LDPC) encoding of data, the method comprising the steps of:

• defining a matrix H;
• generating a matrix HS by cyclically shifting the rows of matrix H until the leftmost subblock of HS contains the identity matrix I along its diagonal;
• triangularizing HS by replacing with zeroes all elements below the identity matrix I along the diagonal;
• and
• mapping the data into an LDPC code word based on the triangularized HS.