Joint Source and Channel Decoding for Variable Length Encoded Turbo Codes. (21st November 2007)

• Record Type: Journal Article
• Authors: Liu Liu, Jianjun Jianjun; Tu Tu, Guofang Guofang; Zhang Zhang, Can Can; Yang Yang, Yang Yang
• Other Names: Dai Dai Huaiyu Huaiyu Academic Editor.
• Is Part Of: EURASIP journal on advances in signal processing. Volume 2008(2008)
• Publication Date: 2007-11-21
• Subjects: Signal processing -- Periodicals; Traitement du signal; Signal processing; Periodicals; 621.3822
• DOI: 10.1155/2008/149839
• Languages: English
• ISSNs: 1687-6172

Abstract

Abstract : Joint source and channel decoding (JSCD) has been proved to be an effective technique which can improve decoding performance by exploiting residual source redundancy. Most previous publications on this subject focus on a traditional coding scheme in which the source variable-length coding (VLC) is serially concatenated with a channel code. In this paper, a parallel concatenated coding scheme for the VLC combined with a turbo code is presented. By merging a symbol-level VLC trellis with a convolutional trellis, we construct a symbol-level joint trellis with compound states. Also, a solution of the symbol-by-symbol a posteriori probability (APP) decoding algorithm based on this joint trellis is derived, which leads to an iterative JSCD approach in the similar way to the classical turbo decoder. The simulation results show that our joint source-channel en/decoding system achieves some gains at the cost of increasing decoding complexity, when compared to the joint iterative decoding based on the bit-level super trellis for the separate coding system.