Iterative source-channel decoder using symbol-level extrinsic information

Author

Pan, Yen-Chang ; Wu, Chun-Feng ; Chang, Wen-Whei

Author_Institution

Dept. of Commun. Eng., Nat. Chiao-Tung Univ., Hsinchu, Taiwan

fYear

2009

fDate

8-10 Dec. 2009

Firstpage

1

Lastpage

4

Abstract

An iterative source-channel decoding scheme which exploits the source residual redundancies on symbol-basis is proposed. We first derive a modified BCJR algorithm based on the sectionalized code trellis for symbol decoding of the convolutional codes. This is used in conjunction with a softbit source decoder that computes the interpolative a posteriori probabilities of quantizer indexes. Simulation results indicate that our proposed scheme can achieve significant improvement over the conventional bit-level schemes.

Keywords

combined source-channel coding; convolutional codes; iterative decoding; trellis codes; convolutional codes; iterative source-channel decoder; modified BCJR algorithm; quantizer index; sectionalized trellis code; symbol-level extrinsic information; Computational modeling; Concatenated codes; Convolutional codes; Delay; Iterative algorithms; Iterative decoding; Iterative methods; Redundancy; Speech codecs; Transmitters; index-level iterative source-channel decoding; sectionalized trellis diagram;

fLanguage

English

Publisher

ieee

Conference_Titel

Information, Communications and Signal Processing, 2009. ICICS 2009. 7th International Conference on

Conference_Location

Macau

Print_ISBN

978-1-4244-4656-8

Electronic_ISBN

978-1-4244-4657-5

Type

conf

DOI

10.1109/ICICS.2009.5397709

Filename

5397709