LT码固定度分布函数的设计与优化

Design and optimization of LT code in fixed degree distribution function

LT码作为一种新型的无码率信道编码技术,能够适应复杂多变的大气湍流信道,其中度分布是LT码设计的关键。提出了一种新型固定度分布函数的构造方法。仿真结果表明:当码长K取任意数量时,相同译码开销下其译码成功率明显要优于泊松度分布函数,且保留了泊松度分布编译码复杂度为O(K)的特点。

LT code, as a new codeless channel coding technology, can adapt to the complex and changeable atmospheric turbulence channel, in which the degree distribution is the key of LT code design. This paper presents a new method to construct the fixed degree distribution function. Simulation results show that the decoding success rate under the same decoding overhead is obviously better than the poisson degree distribution function when the code length K is taken as an arbitrary number, and the feature of the complexity of the decoding of the poisson degree distribution is retained O(K).