System and method for structured LDPC code family

• US 8,560,911 B2
• Filed: 09/07/2010
• Issued: 10/15/2013
• Est. Priority Date: 09/14/2009
• Status: Expired due to Fees

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Abu-Surra, Shadi, Pisek, Eran, Pi, Zhouyue
• Primary Examiner(s): Baker, Stephen M
• Application Number:
  US12/876,903
• Publication Number:
  US 20110066916A1
• Time in Patent Office: 1,134 Days
• Field of Search: 714/752, 714/774
• US Class Current: 714/752
• CPC Class Codes: H03M 13/03 Error detection or forward error correction by redundancy in data representation, i.e. code words containing more digits than the source words
• CPC Class Codes: H03M 13/033 Theoretical methods to calculate these checking codes
• CPC Class Codes: H03M 13/116 Quasi-cyclic LDPC [QC-LDPC] codes, i.e. the parity-check matrix being composed of permutation or circulant sub-matrices
• CPC Class Codes: H03M 13/1165 QC-LDPC codes as defined for the digital video broadcasting [DVB] specifications, e.g. DVB-Satellite [DVB-S2]
• CPC Class Codes: H03M 13/118 Parity check matrix structured for simplifying encoding, e.g. by having a triangular or an approximate triangular structure H03M13/1165 takes precedence
• CPC Class Codes: H03M 13/635 Error control coding in combination with rate matching
• CPC Class Codes: H03M 13/6516 Support of multiple code parameters, e.g. generalized Reed-Solomon decoder for a variety of generator polynomials or Galois fields
• CPC Class Codes: H03M 13/6525 3GPP LTE including E-UTRA
• CPC Class Codes: H03M 13/6544 IEEE 802.16 (WIMAX and broadband wireless access)
• CPC Class Codes: H04L 1/0057 Block codes H04L1/0061, H04L1/0064 take precedence

Abstract

A low density parity check (LDPC) family of codes is constructed by: determining a protograph for a mother code for the LDPC family of codes. The protograph is lifted by a lifting factor to design code specific protograph for a code. The method also includes constructing a base matrix for the code. The base matrix is constructed by replacing each zero in the code specific protograph with a ‘−1’; and replacing each one in the code specific protograph with a corresponding value from the mother matrix. The LDPC code includes a codeword size of at least 1344, a plurality of information bits, and a plurality of parity bits. The LDPC code is based on a mother code of code length 672.

Claims

1. A method for constructing a low density parity check (LDPC) family of codes, the method comprising:

determining, by a Context-based operation Reconfigurable Instruction Set Processor (CRISP), a protograph for a mother code for the LDPC family of codes;

lifting the protograph by a lifting factor to design a code specific protograph for a code; and

constructing a base matrix for the code, the base matrix constructed by;

replacing each zero in the code specific protograph with a ‘

−

1’

; and

replacing each one in the code specific protograph with a corresponding value from the mother matrix.

2. The method as set forth in claim 1, wherein the mother code comprises a code length of 672.

3. The method as set forth in claim 1, further comprising selecting circulant blocks, wherein the selecting comprises:

lifting the protograph by a lifting factor of one of 2, 3 and 4.

4. The method as set forth in claim 1, further comprising deriving a second code from the mother code, wherein the second code comprises a second code rate that is lower than the highest code rate.

5. The method as set forth in claim 4, wherein the second code comprises at least one of a rate-⅝

code;

a rate-½

code and a rate-¾

code.

6. The method as set forth in claim 4, wherein the second code comprises a length of at least one of 1344, 2016 and 2688.

7. The method as set forth in claim 4, wherein the constructed codes comprise at least one of:

a same structures as the mother code;

a 4-layers decodable;

a same row and column degree distribution as the mother code; and

can be decoded by a same decoder as the mother code.

8. A Context-based operation Reconfigurable Instruction Set Processor (CRISP) decoder configured perform an error correction using a low density parity check (LDPC) code, the LDPC code comprising:

a codeword size of at least 1344;

a plurality of information bits; and

a plurality of parity bits, wherein the LDPC code is based on a mother code of code length 672, wherein the LDPC code is constructed by;

determining a protograph for a mother code for the LDPC family of codes;

lifting the protograph by a lifting factor to design a code specific protograph for a code; and

constructing a base matrix for the code, the base matrix constructed by;

replacing each zero in the code specific protograph with a ‘

−

1’

; and

replacing each one in the code specific protograph with a corresponding value from the mother matrix.

9. The decoder as set forth in claim 8, further comprising at least one of:

a same structures as the mother code;

a 4-layers decodable;

a same row and column degree distribution as the mother code; and

can be decoded by a same decoder as the mother code.

10. The decoder as set forth in claim 8, wherein the construction of the LDPC code further comprises:

selecting circulant blocks, wherein the selecting comprises;

lifting the protograph by a lifting factor of one of 2, 3 and 4.

11. The decoder as set forth in claim 8, further configured to derive a second code from the mother code, wherein the second code comprises a second code rate that is lower than the highest code rate.

12. The decoder as set forth in claim 11, wherein the second code comprises at least one of a rate-⅝

code;

a rate-½

code and a rate-¾

code.

13. The decoder as set forth in claim 11, wherein the second code comprises a length of at least one of 1344, 2016 and 2688.

14. A method comprising:

performing, by a Context-based operation Reconfigurable Instruction Set Processor (CRISP), an error correction using a low density parity check (LDPC) code from a LDPC family of codes, the LDPC code comprising;

a codeword size of at least 1344;

a plurality of information bits; and

a plurality of parity bits, wherein the LDPC code is based on a mother code, wherein the LDPC code is constructed by;

determining a protograph for a mother code for the LDPC family of codes;

lifting the protograph by a lifting factor to design a code specific protograph for a code; and

constructing a base matrix for the code, the base matrix constructed by;

replacing each zero in the code specific protograph with a ‘

−

1’

; and

replacing each one in the code specific protograph with a corresponding value from the mother matrix.

15. The method as set forth in claim 14, wherein the mother code comprises a code length of 672.

16. The method as set forth in claim 14, further comprising selecting circulant blocks, wherein the selecting comprises:

lifting the protograph by a lifting factor of one of 2, 3 and 4.

17. The method as set forth in claim 14, further comprising deriving a second code from the mother code, wherein the second code comprises a second code rate that is lower than the highest code rate.

18. The method as set forth in claim 17, wherein the second code comprises at least one of a rate-⅝

code;

a rate-½

code and a rate-¾

code.

19. The method as set forth in claim 17, wherein the second code comprises a length of at least one of 1344, 2016 and 2688.

20. The method as set forth in claim 17, wherein the constructed codes comprise at least one of:

a same structures as the mother code;

a 4-layers decodable;

a same row and column degree distribution as the mother code; and

can be decoded by a same decoder as the mother code.