系统工程与电子技术

• 通信与网络 • 上一篇    下一篇

基于无码率码的独立窗不等差错保护方案

陈英,顾术实,焦健,李云鹤,吴绍华,张钦宇   

  1. 哈尔滨工业大学深圳研究生院通信工程研究中心, 广东 深圳 518055
  • 出版日期:2014-05-22 发布日期:2010-01-03

Independent window UEP scheme based on rateless codes

CHEN Ying, GU Shu-shi, JIAO Jian, LI Yun-he, WU Shao-hua, ZHANG Qin-yu   

  1. Communication and Engineering Research Center, Harbin Institute of Technology Shenzhen Graduate School, Shenzhen 518055, China)
  • Online:2014-05-22 Published:2010-01-03

摘要:

提出一种能够匹配多媒体业务特性的独立窗口LT码(independent window LT, IW-LT)不等差错保护方案,采用无码率LT码对不同重要等级的数据分别进行独立选窗和编码。通过与或树分析法推导了IWLT码的渐近译码性能,并结合多目标进化算法联合优化编码度分布和选窗概率,以精确匹配预设的不等保护增益及译码开销,增加了不等差错保护方案的灵活性。仿真证明,IWLT码与现有的无码率码不等差错保护方案相比,能在精确匹配不等差错性能参数的前提下,获得更低的译码差错概率。

Abstract:

To match the multimedia service transmission, an unequal error protection (UEP) scheme based on the independent window LT (IW-LT) code is proposed. According to the level of importance, the original data are divided into independent windows and encoded by rateless LT codes. The asymptotic decoding performance of IW-LT codes is derived by the AND-OR tree analysis technique. Moreover, to accurately match the expected UEP gain and decoding overhead, multi-objective genetic algorithms are introduced to optimize the degree distribution and probabilities of selecting windows, which enhance the flexibility of the IW-LT UEP scheme. The simulation results show that, compared with the existing rateless coding UEP scheme, IW-LT codes can obtain a lower decoding error rate under the fixed parameters of UEP property.