基于混沌寻优的大动态非相干信号RELAX测向算法研究  

A relaxation direction finding algorithm for large dynamic incoherent signals based on chaos optimization

作　　者：郭述利 陈云帆 梅竹青 孙中森 GUO Shuli;CHEN Yunfan;MEI Zhuqing;SUN Zhongsen(Qingdao University,Qingdao 266071,China)

机构地区：[1]青岛大学,青岛266071

出　　处：《电波科学学报》2024年第6期1168-1175,共8页Chinese Journal of Radio Science

基　　金：国家重点研发计划战略国际科技合作与创新计划(批准号2018YFE0206500)。

摘　　要：针对电波沿低空链路传播产生的折射效应、接收机与干扰远近差异所导致的非等功率导航干扰信号测向计算量大和测向精度低的问题,提出了一种基于混沌寻优的改进松弛(relaxation, RELAX)算法。该算法利用混沌现象的遍历性、不可重复性和不可预测性等特点,通过将混沌状态引入到优化变量中,在获得一个近似最优解后,利用混沌变量对初始条件的敏感依赖性,在最优解的相邻区域内进行细搜索,大大提高了搜索速度,实现了非等功率导航干扰信号的测向。将该算法用于均匀线阵仿真验证,可实现两个及以上强导航干扰信号弱目标信号共存时测向算法计算量的降低和精度的提高,在弱信号的信噪比高于15 dB且强干扰与弱信号干信比低于25 dB条件下,本文所提算法的测向均方根误差在3°以内,与文内仿真精度最高的算法相比,精准度提升了0.1°~0.2°。Aiming at the problems of large calculation amount and low direction finding accuracy of non-equal power navigation interference signal caused by the refraction effect of radio wave propagation along low altitude link and the difference between receiver and interference distance,an improved relaxation(RELAX)algorithm based on chaos optimization is proposed.The algorithm takes advantage of the ergodic,non-repeatability and unpredictability of chaotic phenomena,and introduces chaotic state into the optimization variables.After obtaining an approximate optimal solution,the algorithm makes use of the sensitive dependence of chaotic variables on initial conditions to conduct a fine search in the adjacent region of the optimal solution,thus greatly improving the search speed and realizing the direction finding of non-equal power navigation interference signals.When the algorithm is applied to the simulation of uniform linear array,it can reduce the computational load and improve the accuracy of the direction finding algorithm when two or more strong navigation interference signals coexist with weak target signals.Under the condition that the signal to noise ratio of the weak signal is higher than 15 dB and the interference to signal ratio of the strong interference to the weak signal is lower than 25 dB,the root mean square of the direction finding algorithm proposed in this paper is less than 3°.Compared with the algorithm with the highest simulation accuracy in the paper,the accuracy is improved by about 0.1°-0.2°.

关 键 词：RELAX算法 混沌优化 强弱信号共存测向 导航干扰信号 均匀线阵 

分 类 号：TN98[电子电信—信息与通信工程]