雷达角闪烁的混沌特性研究

在雷达目标跟踪和控制系统中,雷达角闪烁的大小与目标丢失和误判的概率紧密相连。采用相位梯度法从理论上对共线多散射中心目标的双散射中心和五散射中心的角闪烁进行仿真建模得到了两组角闪烁仿真序列,按照图形电磁学(GRECO)算法对一种典型目标的螺旋运动角闪烁进行了计算,并参考国外学者非线性动力学研究成果设计了一种综合和有效的混沌判定算法计算流程,用洛伦兹吸引子对此算法进行了验证,最后,对各角闪烁时间序列进行混沌仿真验证。混沌验证算法流程首先计算最佳时间延迟和最小嵌入维数,重构吸引子,得到吸引子、庞加莱截面和主分量谱图三种定性判据与关联维数和最大Lyapunov指数两种定量判据的判定结果,依据混沌判定准则及对比洛伦兹吸引子的验证结果,验证了角闪烁的混沌特性,为抑制角闪烁和降低丢失目标概率拓展了新思路。

Chaotic characteristics of angular glint

In radar tracking and target control systems,the angular glint is a key factor in the generation of loss probability of targets tracking.This paper realizes the glint modeling of N-point scattering centers on the same line by the widely accepted phase gradient method,and two and five scattering center objects together with a typical target by Greco method are simulated.With references of foreign research results,the paper focuses on the comprehensive and effective design of the chaotic verification calculation flow based on the nonlinear dynamic theories,and the flow is proved valid by the Lorenz attractor model.The algorithm flow begins with the determination of optimum time lag and minimum embedding dimension,and is followed by the time-delay reconstruction in phase space.The results are presented with both qualitative calculations such as attractor configuration,poincare section and principal component analysis and quantitative calculations such as correlation dimension and largest lyapunov exponent,for the glint series,and with comparison with results obtained by Lorenz attractor,the chaotic traits of angular glint data are verified.This paper develops new reduction ideas to refrain the angular glint in order to decrease the loss probability of radar targets based on chaotic theories.