Encoding method and encoding apparatus

• US 7,484,159 B2
• Filed: 03/03/2005
• Issued: 01/27/2009
• Est. Priority Date: 03/05/2004
• Status: Expired due to Fees

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Kikuchi, Atsushi, Yokokawa, Takashi, Miyauchi, Toshiyuki, Kan, Makiko
• Primary Examiner(s): Lamarre; Guy J
• Application Number:
  US11/071,096
• Publication Number:
  US 20050204261A1
• Time in Patent Office: 1,426 Days
• Field of Search: 714/755, 714785-786, 714/781
• US Class Current: 714/755
• 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 13/118 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 13/1185 wherein the parity-check matrix comprises a part with a double-diagonal
• CPC Class Codes: H03M 13/1194 Repeat-accumulate [RA] codes

Abstract

Disclosed is an apparatus for encoding data into linear codes on a ring R, including: as many shift registers as the length of information input thereto, the shift registers having a plurality of memory elements; a shift adding unit for adding values which are cyclically input depending on a check matrix for the linear codes, from the shift registers; a storage unit for storing parity values of the linear codes; and an accumulative adding unit for adding a sum from the shift adding unit and the parity values of the linear codes stored in the storage unit to each other to determine new parity values of the linear codes, and supplying the new parity values to the storage unit.

Claims

1. An apparatus for encoding data into linear codes on a ring R, comprising:

as many shift registers as the length of information input thereto, said shift registers having a plurality of memory elements;

a shift adding unit for adding values which are cyclically input depending on a check matrix for said linear codes, from said shift registers;

a storage unit for storing parity values of said linear codes; and

an accumulative adding unit for adding a sum from said shift adding unit and the parity values of said linear codes stored in said storage unit to each other to determine new parity values of said linear codes, and supplying the new parity values to said storage unit.

2. An apparatus according to claim 1, wherein said check matrix for said linear codes is of a low density.

3. An apparatus according to claim 1, wherein said ring R comprises a finite field having elements represented by a power of a prime number.

4. An apparatus according to claim 1, further comprising:

a selecting unit for selecting the sum from said shift adding unit depending on the check matrix for said linear codes;

wherein said accumulative adding unit adds the sum selected by said selecting unit and the parity values of said linear codes stored in said storage unit to each other to determine the new parity values of said linear codes, and supplies the new parity values to said storage unit.

5. A method of encoding data into linear codes on a ring R, comprising the steps of:

adding values which are cyclically input depending on a check matrix for said linear codes from as many shift registers as the length of information input thereto, said shift registers having a plurality of memory elements;

storing parity values of said linear codes in a storage unit; and

accumulatively adding a sum from said adding step and the parity values of said linear codes stored in said storage unit to each other to determine new parity values of said linear codes, and supplying the new parity values to said storage unit.

6. A method according to claim 5, wherein said check matrix for said linear codes is of a low density.

7. A method according to claim 5, wherein said ring R comprises a finite field having elements represented by a power of a prime number.

8. A method according to claim 5, further comprising the step of:

selecting the sum from said adding step depending on the check matrix for said linear codes;

wherein said accumulatively adding step adds the sum selected by said selecting step and the parity values of said linear codes stored in said storage unit to each other to determine the new parity values of said linear codes, and supplies the new parity values to said storage unit.