复制窗口不等保护喷泉码的与或树渐进性能分析

采用与或树分析方法,结合算法的构造,推导出复制窗口不等保护算法中各类数据的译码失败概率迭代公式.从数学的角度验证算法性能.通过Matlab性能仿真,给出在不同复制因数下复制窗口不等保护算法与算法误比特率性能关系曲线.通过与基于权重的不等保护算法及拓展窗口喷泉码的渐进性能仿真结果进行对比,证明了该算法在相同译码开销下,可将保护级别提高3~4个数量级.此外,本文研究了复制因数对算法性能的影响,在不同的译码开销下,通过Matlab仿真给出复制因数与算法性能的关系曲线.

And-Or tree asymptotic analysis of duplicate window unequal error protection fountain code

To provide theoretical support for balise telegram coding strategy using fountain codes with UEP（ unequal error protection） property,this paper derives the iteration expressions for asymptotic erasure probabilities of the duplicate window algorithm by And-Or tree analysis. We verify algorithm performance through mathematical analysis and get the BER curve by Matlab under different repeat factors. Compared with weighted UEP algorithm and EWF algorithm,duplicate window algorithm can improve 3-4 orders of magnitude at the same overhead. In addition,this paper gives the curve of BER versus repeat factors by Matlab under different decoding overheads,and comes to a general conclusion.