Convergence behavior of iteratively decoded parallel concatenated codes

被引：1680

作者：

ten Brink, S ^{[1
]}

机构：

[1] Bell Labs, Wireless Res Lab, Lucent Technol, Holmdel, NJ 07733 USA

来源：

IEEE TRANSACTIONS ON COMMUNICATIONS | 2001年 / 49卷 / 10期

关键词：

convergence; iterative decoding; mutual information; turbo codes;

D O I：

10.1109/26.957394

中图分类号：

TM [电工技术]; TN [电子技术、通信技术];

学科分类号：

0808 ; 0809 ;

摘要：

Mutual information transfer characteristics of soft in/soft out decoders are proposed as a tool to better understand the convergence behavior of iterative decoding schemes. The exchange of extrinsic information is visualized as a decoding trajectory in the extrinsic information transfer chart (EXIT chart). This allows the prediction of turbo cliff position and bit error rate after an arbitrary number of iterations. The influence of code memory, code polynomials as well as different constituent codes on the convergence behavior is studied for parallel concatenated codes. A code search based on the EXIT chart technique has been performed yielding new recursive systematic convolutional constituent codes exhibiting turbo cliffs at lower signal-to-noise ratios than attainable by previously known constituent codes.

引用

页码：1727 / 1737

页数：11