频率捷变雷达跟踪海面低空目标的频点自适应优化技术  

Adaptive Frequency Point Optimization Technique for Frequency Agility Radar Tracking Low Altitude Targets on the Sea Surface

作　　者：王娜 张劲东[1] 徐婧 柏磊 WANG Na;ZHANG Jingdong;XU Jing;BAI Lei(College of Electronic and Information Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing,Jiangsu 211106,China;CSIC Eighth Research Institute,Yangzhou,Jiangsu 225000,China)

机构地区：[1]南京航空航天大学电子信息工程学院,江苏南京211106 [2]中船重工第八研究院,江苏扬州225000

出　　处：《信号处理》2022年第10期2041-2052,共12页Journal of Signal Processing

基　　金：国家自然科学基金(62171220)资助课题。

摘　　要：针对雷达跟踪海面低仰角目标产生多径效应引起的仰角测量误差问题,本文建立了海面多径反射和频率捷变下低角误差测量模型,提出了一种基于频率捷变自适应优化的改善低角测量误差方法。该方法通过宽带频率捷变去除目标信号与多径反射信号的相关性,利用网格自适应直接搜索算法(Mesh Adaptive Direct Search Algorithms,MADS)优化频点技术,根据不同距离、不同高度和不同海情产生多径效应的大小自动选择频点改善误差,形成了雷达自适应频率捷变对抗海面低空目标多径的方法。仿真结果表明,该方法能根据不同情况自动选择低误差频点,控制每一个距离的低角测量误差在±2 mrad内,基于网格自适应直接搜索的频点优化算法也大大提高了频点选择速度,减少了迭代次数,表明了该优化算法的有效性。In this paper,the elevation measurement error caused by multipath effect was studied when radar tracked low el⁃evation targets on the sea surface.Firstly,the multipath reflection effect and frequency agility radar system model of sea surface signal were established,and the elevation error model of frequency agility radar under multipath effect was solved by bringing the target into the model.A low angle measurement error improvement method based on adaptive frequency agility optimization was proposed.The method used wideband frequency agility to remove the correlation between target signal and multipath reflected signal,was developed to reduce the multipath effect,and controlled the error range of eleva⁃tion measurement by selecting the central frequency point.Then,Mesh Adaptive Direct Search Algorithms(MADS)was used to optimize frequency points with low elevation errors,which were automatically selected according to the multipath effects generated by different distances,altitudes and sea conditions.On this basis,a strategy was developed to combat the multipath of the low altitude target on the sea surface through the adaptive frequency agility of radar.The simulation re⁃sults showed that the distance and height of the target,the frequency point of the transmitting signal and the sea condition had great influence on the elevation measurement error.When the parameters of the target and the sea surface remained unchanged,the elevation measurement error could be controlled by selecting the frequency point of the transmitting sig⁃nal.The frequency point optimization algorithm based on mesh adaptive direct search could automatically select low error frequency points according to different conditions,and controlled the low Angle measurement error of each distance within±2 mrad.Compared with the traversal frequency-point method and genetic algorithm,the CPU calculation time of MADS was reduced by nearly 6 times and 2 times,and the number of iterations was reduced by 20 times and 2 times,respec⁃tively.The algo

关 键 词：多径效应 频率捷变 低角测量误差 海面低空目标 网格自适应直接搜索算法 

分 类 号：TN974[电子电信—信号与信息处理]