极化码串行抵消解码算法误码特性研究

项目名称： 极化码串行抵消解码算法误码特性研究

项目编号： No.61501002

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 无线电电子学、电信技术

项目作者： 李莉萍

作者单位： 安徽大学

项目金额： 19万元

中文摘要： 我们已经知道，极化码在使用串行抵消解码算法（SC解码）时，会出现错误的传播现象。此错误传播的特性使得极化码在码长有限的场合下，误码性能不如现有的LDPC码，导致其低复杂的解码优势大大降低。学界目前的解决方式是使用高复杂度的解码算法，比如BP解码算法，来提高极化码的性能。但是在使用这些高复杂度的解码算法的同时，我们却缺乏对SC算法本身的了解。当一个信息比特出错时，这个错误是随机地影响其后的信息比特，还是以一定的规律来影响其后的信息比特？如果是具有规律性的，那这个规律是什么？我们前期的研究结果显示，比特的错误传播具有规律性。本项目通过研究极化码在SC解码时的误码特性，以建立误码的统计规律模型和比特间错误的关联模型。这些模型的建立在加深我们对SC解码算法自身认识的同时，也可以通过利用这些模型来降低现有的高复杂度的解码算法，并在此基础上设计新的、有效的、低复杂度的极化码解码方法。

中文关键词： 信道编码；极化码；编译码

英文摘要： As it’s already studied in the literature, errors propagate in polar codes with the successive cancellation (SC) decoding. Due to this property, polar codes with a finite block length and the SC decoding have worse error performance than LDPC codes, which greatly compromises their advantage as low-complexity codes. Other decoding algorithms, such as belief propagation (BP) decoding, are proposed to improve the performance of polar codes with finite block lengths and the SC decoding. While using these high complexity decoding algorithms, there are few studies to help us understanding the SC algorithm itself. We know errors propagate with the SC decoding, but how the errors are propagated? Is the propagation random or is it propagating with some patterns? If there are patterns, what are these patterns? Our current research shows that the error propagation of the SC decoding has fixed patterns. In this work, we study the error patterns of the SC decoding, trying to establish a statistical model and a bits-correlation model. These models can help us to better understand the SC algorithm itself. More importantly, they can be used to improve the current decoding algorithms and foster new efficient and low complexity decoding algorithms.

英文关键词： Channel Codeing;Polar Codes;Coding/Decoding