高距离分辨率雷达的低空目标高度估计方法

Height Estimation on Low-Altitude Target for HRR Radar

雷达在跟踪海面(地面)低空目标时,由于受到多路径反射效应的影响,由目标反射的直接回波和经由海面(地面)反射的反射回波同存在于一个接收天线波束宽度内,从而产生“角闪烁”效应。该文利用直接回波和反射回波之间的多路径时间差与目标高度之间的关系,提出了一种基于目标高分辨一维距离像的测高方法,即通过对高分辨一维距离像进行自相关获得多路径时延差进而估计低空目标的高度。为了提高时域分辨率,避免“栅栏效应”,文中又采用逆Chirp-z变换方法,通过对频域接收信号进行密集采样插值,提高时域目标高分辨一维距离像的分辨能力并改善雷达测高性能。仿真结果验证了本方法的有效性。

To overcome the question of angular glint when radar tracks low-altitude target, a method to measure target height is proposed based on the high range resolution profile（HRRP）. Through the auto-correlation of HRRP, the multipath time delay can be obtained, and the target height can be acquired. To improve the resolution and keep away from＂barrier effect＂, the Inverse Chirp-z Transform（ICZT） is applied to acquire accurate HRRP and improve target height precision. Simulation results show the validity of the method.