三种重拖尾分布海杂波的比较与分析

Comparison and analysis of three kinds of distribution of sea clutter with heavy tails

针对雷达杂波的概率密度函数具有非对称和重拖尾等非高斯特征,对描述海杂波的K-分布,α-稳定分布和G-分布等三种重拖尾分布模型进行比较和分析。K-分布的重拖尾特性较轻微;α-稳定分布的重拖尾特性源自其方差无限大,重拖尾最严重;G-分布由二元Rayleigh独立积随机变量和广义χ分布随机变量进行级联而生成的三元独立积,重拖尾特性介于两者之间。最后使用Markov扩散过程模型产生G-分布杂波的相关随机变量,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 non-Gaussian signature of radar clutter, such as non- symmetric probability density function （pdf） with heavy tails, three kinds of pdf have been investigated, i. e. , K-distribution, α-stable distribution and G-distribution. The heavy tail of K-distribution is slight, and the tail of α-stable distribution is heaviest because its variance is infinite. G-distribution is the product of three independent random variables by using two independent Rayleigh variables multiplied by a X distributed random variable with n degrees of freedom, and its heavy tail is mediate. Markov diffusion processes are used to generate correlated random variables of G-distribution. The simulation results are similar to the theoretical value.