{"title":"Protograph-based LDPC codes for partial response channels","authors":"T. Nguyen, Aria Nosratinia, D. Divsalar","doi":"10.1109/ICC.2012.6364385","DOIUrl":null,"url":null,"abstract":"This paper addresses the design of a protograph-based LDPC code which can approach the independent and uniformly distributed (i.u.d.) capacity of partial response channels. We propose a method to calculate the iterative decoding threshold of a joint graph between a protograph and the state structure of a partial response channel using the extrinsic information transfer (EXIT) chart. We then describe a simple method to search for a protograph code whose threshold is close to the i.u.d. capacity limit. This new class of codes is needed because experiments show a protograph that is capacity approaching in the AWGN channel may not perform well in partial response channels. In particular, protographs with punctured nodes are often used to produce good AWGN codes, but they perform poorly with the BCJR equalizer. Numerical results support our analysis.","PeriodicalId":331080,"journal":{"name":"2012 IEEE International Conference on Communications (ICC)","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2012-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"17","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"2012 IEEE International Conference on Communications (ICC)","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1109/ICC.2012.6364385","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 17
Abstract
This paper addresses the design of a protograph-based LDPC code which can approach the independent and uniformly distributed (i.u.d.) capacity of partial response channels. We propose a method to calculate the iterative decoding threshold of a joint graph between a protograph and the state structure of a partial response channel using the extrinsic information transfer (EXIT) chart. We then describe a simple method to search for a protograph code whose threshold is close to the i.u.d. capacity limit. This new class of codes is needed because experiments show a protograph that is capacity approaching in the AWGN channel may not perform well in partial response channels. In particular, protographs with punctured nodes are often used to produce good AWGN codes, but they perform poorly with the BCJR equalizer. Numerical results support our analysis.
本文讨论了一种基于原型的LDPC码的设计,该码可以接近部分响应信道的独立和均匀分布(i.u.d)容量。提出了一种利用外在信息传递(extrinsic information transfer, EXIT)图计算原图与部分响应信道状态结构之间的联合图的迭代解码阈值的方法。然后,我们描述了一种简单的方法来搜索其阈值接近输液器容量限制的原型代码。由于实验表明,在AWGN信道中容量接近的原型可能在部分响应信道中表现不佳,因此需要这种新型编码。特别是,带有穿刺节点的原型通常用于生成良好的AWGN代码,但它们在BCJR均衡器上表现不佳。数值结果支持了我们的分析。