雷达导引头跟踪超低空目标时,由于目标镜像多径干扰会引起单脉冲跟踪指示角误差。文中建立了存在镜像目标时的单脉冲差和比模型,推导了单脉冲跟踪指示角误差模型,得到了开环与闭环跟踪模式的指示角解析表达式,仿真分析结果表明,对于开环跟踪,当镜像目标与真实目标相对相位相差180°时,指示角误差最大;对于闭环跟踪,指示角误差偏离程度与弹目距离、目标高度、天线增益、反射系数相关,弹目距离越近,指示角波动幅度越大。
When radar seeker tracks low altitude target, monopulse tracking indication angle error will be caused due to target specular multipath interference. To solve this problem, a difference and ratio model was established under specular multipath interference, a mono- pulse tracking indication angle error model was deduced, an indication angle analytical expression was derived when radar seeker worked in open-loop and closed-loop tracking mode. Simulation results show that, for open-loop tracking, when the relative phase difference is 180° between specular interference and real target, the indication angle error is maximum; For closed-loop tracking, indication angle error is as- sociated with the distance between target and missile, target height, antenna gain, and reflection coefficient. The closer the distance be- tween target and missile is, the greater the indication angle fluctuations.