ACM语音和语言处理TSLP(ACM Transactions on Speech and Language Processing)侧重于语音和文本处理系统及其相关理论的设计、开发和评估的实践领域。TSLP范围内的主题包括:自然语言理解、生成和解析;对话框管理;机器翻译;文档摘要;问题回答;实体、关系、主题和新颖性的检测和跟踪;机器翻译和语音的语言建模语音韵律;音频索引;语音文档检索。 官网地址:


In this paper, we analyze the error floor of quasi-cyclic (QC) low-density parity-check (LDPC) codes decoded by the sum-product algorithm (SPA) with row layered message-passing scheduling. For this, we develop a linear state-space model of trapping sets (TSs) which incorporates the layered nature of scheduling. We demonstrate that the contribution of each TS to the error floor is not only a function of the topology of the TS, but also depends on the row layers in which different check nodes of the TS are located. This information, referred to as TS layer profile (TSLP), plays an important role in the harmfulness of a TS. As a result, the harmfulness of a TS in particular, and the error floor of the code in general, can significantly change by changing the order in which the information of different layers, corresponding to different row blocks of the parity-check matrix, is updated. We also study the problem of finding a layer ordering that minimizes the error floor, and obtain row layered decoders with error floor significantly lower than that of their flooding counterparts. As part of our analysis, we make connections between the parameters of the state-space model for a row layered schedule and those of the flooding schedule. Simulation results are presented to show the accuracy of analytical error floor estimates.