共查询到18条相似文献,搜索用时 203 毫秒
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一种新的IP网络视频通信丢包错误纠正方案 总被引:2,自引:0,他引:2
分组丢失是IP交换网络常见的现象。该文针对下一代网络多媒体通信,提出了一套IP网络抗分组丢失的方案。包括纠删编码、打包和发送以及接收端错误掩盖。与常见的纠删编码相比,该文提出的[9,5,3]码具有构造简单,编解码时间短,纠删能力高的优点。打包和发送方案根据[9,5,3]码的纠删性能对视频数据打包,并以一定顺序发送,提高了纠删码抗突发错误的能力。采用新的视频编码方案H.264所提供的抗误码工具——灵活的宏块次序(FMO),对纠删失效的视频数据在解码端进行错误掩盖。 相似文献
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针对范德蒙阵列纠删码算法,介绍了纠删码编译码过程,重点论述了范德蒙码编码算法和译码算法,提出了适合在嵌入式系统实现时的快速算法;在Matlab软件中构建了数字卫星广播系统(DVB-S)模型并进行了信道误码分布仿真,获得了DVB-S系统的误码分布,分析了在系统中使用范德蒙纠删码的可行性;提出了纠删码与系统中的纠错码级联使用模型,并对算法的纠错性能进行仿真,仿真结果表明级联模型能大大提高无线传输系统的可靠性。 相似文献
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本文提出了一种基于(2、1,m)卷积码的网络毛包错误恢复新方法,给出了(2,1,m)系统卷积码的纠删解码算法和判定定理,并证明了最优列距离剖面码具有最优延迟特性。实验结果证明本方法可以在不同的解码延迟条件下保持良好的效果,从而能适应不同的网络延迟条件。 相似文献
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大数据分布式存储系统中,修复流水线(Repair Pipelining,RP)减少90%的修复时间,有效地解决由于修复时间开销较大,纠删码不适用于存储热数据的问题.然而,现有的RP存在节点负载不均衡的问题,导致系统性能下降.通过研究后,设计节点负载均衡的纠删码修复流水线(Node Load Balancing-based Repair Pipelining,NLB-RP),并根据性能评价指标提出计算节点负载的算法和计算修复时间的算法.理论分析及实验结果表明,在没有引入额外修复代价的情况下,NLB-RP从局部到整体有效地平衡并减少节点的负载.相比RP,NLB-RP的节点负载方差为0,即每个节点的负载相同.因此,NLB-RP具有最优的负载均衡性. 相似文献
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针对当前灾备存储系统数据冗余度高的不足,文中提出了将纠删码技术与P2P技术相结合的可信存储系统架构。并设计了与纠删码技术相匹配的分布式散列表,使得系统更快速有效的定位和获取资源;实现了比传统P2P存储系统更完善的管理机制,克服了其存在废弃数据的缺点,能够彻底的删除废弃文件,有效利用存储资源。文中还提供了有效的数据恢复机制,即使灾难来,临,部分存储服务器损坏,系统也能恢复丢失的数据。 相似文献
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Dan Tang 《电子科技学刊:英文版》2016,14(1):43-48
In the process of encoding and decoding, erasure codes over binary fields, which just need AND operations and XOR operations and therefore have a high computational efficiency, are widely used in various fields of information technology. A matrix decoding method is proposed in this paper. The method is a universal data reconstruction scheme for erasure codes over binary fields. Besides a pre-judgment that whether errors can be recovered, the method can rebuild sectors of loss data on a fault-tolerant storage system constructed by erasure codes for disk errors. Data reconstruction process of the new method has simple and clear steps, so it is beneficial for implementation of computer codes. And more, it can be applied to other non-binary fields easily, so it is expected that the method has an extensive application in the future. 相似文献
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In this paper low-density parity-check (LDPC) codes are designed for burst erasure channels. Firstly, lower bounds for the maximum length erasure burst that can always be corrected with message-passing decoding are derived as a function of the parity-check matrix properties. We then show how paritycheck matrices for burst erasure correcting LDPC codes can be constructed using superposition, where the burst erasure correcting performance of the resulting codes is derived as a property of the stopping set size of the base matrices and the choice of permutation matrices for the superposition. This result is then used to design both single burst erasure correcting LDPC codes which are also resilient to the presence of random erasures in the received bits and LDPC codes which can correct multiple erasure bursts in the same codeword. 相似文献
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Ai Da Chang Yilin Luo Zhong Wang Jing 《电子科学学刊(英文版)》2006,23(2):274-276
Tornado codes have been used in the error control of data transmission in IP network. The efficiency of this erasure codes is critically affected by the short cycles in its bipartite graph. To remove this effect, two algorithms are introduced: (1) while generating the graph, the cycle eliminating algorithm is used to reduce the number of the short cycles in it; (2) in the decoding algorithm, cycles that are inevitably in the graph are used to remove decoding efficiency degradation. The simulation results show that they have a better performance than that of general tornado codes. 相似文献
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摘 要:Ustor是一个构建在多个商业云存储服务之上的云存储系统,它旨在保证数据可靠性的同时减少单点失效时占用的修复带宽。不同于将所有数据存储在单个云中,Ustor将数据编码后分布在多个云存储系统中保证可靠性。Ustor的编码模块部署了包括Reed-Solomon码和功能性修复再生码(FRC)在内的多种纠删码,是第一个将功能性修复再生码应用于多个异构的、真实的云存储系统中的应用。与传统的冗余编码比较,FRC显著地减少了单个云存储发生数据丢失时需要从网络上传输的数据量。实验表明:与不编码比较,冗余编码给系统增加了5%~10%的响应时间开销,但可保障节点失效;FRC码编、解码和修复速度与Reed-Solomon码基本相当,256 MB大小文件编码时间差距在0.5 s以内;FRC码修复时与传统的Reed-Solomon码相比减少了25%以上需要下载的数据量。 相似文献
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