数字喷泉码度分布优化设计的最新研究进展
Recent Progress on Optimization Design of Degree Distributions in Digital Fountain Codes

数字喷泉码是一种速率码,能 够有效避免大规模网络广播组播传输中的“反馈风暴”问题,在大数据的网络传输中具有广 阔的应用前景。本文论述了当前数字喷泉码的研究现状，分别介绍了不同信道条件下几种典 型的数字喷泉码。度分布是数字喷泉码设计的基础，本文总结了现有数字喷泉码度分布优化 设计方面的研究工作，重点介绍了不同信道下基于密度演化方法的度分布设计模型,并分析 了存在的不足及改进之处。最后，对数字喷泉码的设计、应用和发展趋势给出了分析和展望 。
Digital fountain codes are an effectiv e kind of rateless codes to avoid “feedback storm” in network broadcast/multic ast with a wide horizon of development in the network transmission of big data. Therefore, the recent research progress of digital fountain codes is summerized and some typical digital fountain codes are intro duced in different c hannels. Since degree distributions are fundamental to design digita l fountain codes, previous work about optimization design of degree distribut i ons is summarized and some linear optimization techniques over different channel s based on density evolution are presented in particular. Meanwhile, the problem s of optimization design are pointed out and some possible improvements are proposed. Finally, the outlook of optimization design in degree distributions and a p plications of digital fountain codes is analyzed.