Joint source-channel iterative decoding of codes

In this paper an innovative joint source channel coding scheme is presented. The system is based on iterative soft decoding of arithmetic codes, by means of a novel soft-in soft-out decoder based on suboptimal search and pruning of a binary tree. An error resilient arithmetic coder with a forbidden symbol is used in order to improve the performance of the joint source/channel scheme. The performance in the case of transmission across the AWGN channel is evaluated in terms of frame error rate, and compared to a traditional separated approach. Finally the convergence property of the system is analyzed by means of the EXIT chart technique.