针对雷达杂波具有尖峰、非对称和重拖尾等非高斯特征,使用二元Rayleigh独立积和自由度为n的广义x~2分布的随机变量进行级联,得到扩展K-分布随机变量。二元Rayleigh独立积使得扩展K-分布比K-分布在概率密度函数上具有更为明显的尖峰和重拖尾,且二元Rayleigh独立积的出现与高分辨率雷达杂波的散射机制相符。使用Markov扩散过程模型产生相关的扩展K-分布杂波随机变量。仿真得到的随机序列的概率密度分布与理论值吻合很好。

In order to model the probability density function (pdf) of radar clutter, which has some non-gaussian features, i.e., peak, asymmetry and heavy tail, the extended K-distribution random variables are obtained through multiplying the product of two independent rayleigh variables by generalized X~2 distribution random variable with n degrees of freedom. This pdf of extended K-distribution has more significant peak and heavier tail than that of previous K-distribution with the help of the product of two independent Rayleigh variables, whose effect corresponds well with the scattering mechanism of clutter of high resolution radar. Besides, the model of Markov diffusion process is used to generate correlated random variables of the extended K-distribution. The simulation results of the above pdf correspond well with the theoretical value.

TN911.7

国家自然科学基金项目(60572024)，教育部新世纪优秀人才支持计划(NCET-04-0519)，教育部博士点基金项目(200509230031)资助课题。