SOURCE-CHANNEL APPROACH TO CHANNEL CODING WITH SIDE INFORMATION

• US 20110311003A1
• Filed: 08/29/2011
• Published: 12/22/2011
• Est. Priority Date: 03/15/2006
• Status: Active Grant

• Current Assignee: Texas A&M University System
• Original Assignee: Texas A&M University System
• Inventors: Sun, Yong, Liveris, Angelos D., Stankovic, Vladimir M., Xiong, Zixiang
• Granted Patent: US 8,245,119 B2
• Time in Patent Office: Days
• US Class Current: 375/341
• CPC Class Codes: H03M 13/1194 Repeat-accumulate [RA] codes
• CPC Class Codes: H03M 13/31 combining coding for error detection or correction and efficient use of the spectrum without error detection or correction H03M5/14 , H03M5/145
• CPC Class Codes: H03M 7/40 Conversion to or from variable length codes, e.g. Shannon-Fano code, Huffman code, Morse code

Abstract

Code designs for channel coding with side information (CCSI) based on combined source-channel coding are disclosed. These code designs combine trellis-coded quantization (TCQ) with irregular repeat accumulate (IRA) codes. The EXIT chart technique is used for IRA channel code design (and especially for capacity-approaching IRA channel code design). We emphasize the role of strong source coding and endeavor to achieve as much granular gain as possible by using TCQ. These code designs synergistically combine TCQ with IRA codes. By bringing together TCQ and EXIT chart-based IRA code designs, we are able to approach the theoretical limit of dirty-paper coding.

Claims

1. A decoding apparatus, the apparatus comprising:

a processor;

tangible, non-transitory computer-readable medium having computer-executable instructions stored thereon that, if executed by the processor, cause the processor to perform operations comprising;

decoding an input signal in order to generate first feedforward information, wherein the decoding comprises;

performing trellis decoding on the input signal over a joint trellis corresponding at least to an accumulator portion of an irregular repeat accumulate (IRA) encoder and a trellis coded quantization, and

performing first check node decoding on data including a modified version of output from the trellis decoding, wherein the first feedforward information is a modified version of output from the first check node decoding; and

generating feedback information from the feedforward information.

2. The apparatus as defined in claim 1, wherein generating feedback information from the feedforward information further comprises:

decoding a permuted version of the first feedforward information, wherein said decoding the permuted version of the first feedforward information includes;

performing variable node decoding, corresponding to variable nodes of the IRA encoder, on the permuted version of the first feedforward information,

wherein the first feedback information is a modified version of output from the variable node decoding.

3. The apparatus as defined in claim 2, the operations further comprising:

determining an estimate for the message bits from the output of the variable node decoding; and

storing the estimate for the message bits in a memory medium.

4. The apparatus as defined in claim 1, wherein generating feedback information from the feedforward information further comprises:

decoding a permuted version of the first feedforward information in order to generate first feedback information,

wherein said decoding the permuted version of the first feedforward information includes performing variable node decoding on the permuted version of the first feedforward information.

5. The apparatus as defined in claim 1, wherein said decoding further comprises performing second check node decoding on a permuted version of the first feedback information, wherein the trellis decoding uses output from the second check node decoding.

6. The apparatus as defined in claim 1, wherein the input signal is a scaled and dithered version of a received signal.

7. A method comprising:

decoding an input signal in order to generate first feedforward information, wherein the decoding comprises;

performing trellis decoding on the input signal over a joint trellis corresponding at least to an accumulator portion of an irregular repeat accumulate (IRA) encoder and a trellis coded quantization, and

performing first check node decoding on data including a modified version of output from the trellis decoding, wherein the first feedforward information is a modified version of output from the first check node decoding; and

generating feedback information from the feedforward information.

8. The method as defined in claim 7, wherein generating feedback information from the feedforward information further comprises:

decoding a permuted version of the first feedforward information, wherein said decoding the permuted version of the first feedforward information includes;

performing variable node decoding, corresponding to variable nodes of the IRA encoder, on the permuted version of the first feedforward information,

wherein the first feedback information is a modified version of output from the variable node decoding.

9. The method as defined in claim 8, the operations further comprising:

determining an estimate for the message bits from the output of the variable node decoding; and

storing the estimate for the message bits in a memory medium.

10. The method as defined in claim 7, wherein generating feedback information from the feedforward information further comprises:

decoding a permuted version of the first feedforward information in order to generate first feedback information,

wherein said decoding the permuted version of the first feedforward information includes performing variable node decoding on the permuted version of the first feedforward information.

11. The method as defined in claim 7, wherein said decoding further comprises performing second check node decoding on a permuted version of the first feedback information, wherein the trellis decoding uses output from the second check node decoding.

12. The method as defined in claim 7, wherein the input signal is a scaled and dithered version of a received signal.

13. A tangible, non-transitory computer-readable medium having computer-executable instructions stored thereon that, if executed by the processor, cause the processor to perform operations comprising:

decoding an input signal in order to generate first feedforward information, wherein the decoding comprises;

performing trellis decoding on the input signal over a joint trellis corresponding at least to an accumulator portion of an irregular repeat accumulate (IRA) encoder and a trellis coded quantization, and

performing first check node decoding on data including a modified version of output from the trellis decoding, wherein the first feedforward information is a modified version of output from the first check node decoding; and

generating feedback information from the feedforward information.

14. The medium as defined in claim 13, wherein generating feedback information from the feedforward information further comprises:

decoding a permuted version of the first feedforward information, wherein said decoding the permuted version of the first feedforward information includes;

performing variable node decoding, corresponding to variable nodes of the IRA encoder, on the permuted version of the first feedforward information,

wherein the first feedback information is a modified version of output from the variable node decoding.

15. The medium as defined in claim 14, the operations further comprising:

determining an estimate for the message bits from the output of the variable node decoding; and

storing the estimate for the message bits in a memory medium.

16. The medium as defined in claim 13, wherein generating feedback information from the feedforward information further comprises:

decoding a permuted version of the first feedforward information in order to generate first feedback information,

wherein said decoding the permuted version of the first feedforward information includes performing variable node decoding on the permuted version of the first feedforward information.

17. The medium as defined in claim 13, wherein said decoding further comprises performing second check node decoding on a permuted version of the first feedback information, wherein the trellis decoding uses output from the second check node decoding.

18. The medium as defined in claim 13, wherein the input signal is a scaled and dithered version of a received signal.