ISAR系统相位失真的一种校正方法

A Correction Method for Phase Distortion of ISAR System

逆合成孔径雷达(ISAR)主要应用于雷达静止不动而目标运动的场景,能够获得高分辨的二维图像。ISAR系统比较大的幅相失真会造成散焦等情况,从而使成像模糊,因此有必要对系统的幅相失真进行补偿以提高成像质量。文中给出某ISAR系统相位失真的一种实际校正办法。该系统带内相位原来800°左右的起伏,跟踪空间站时距离门内主副瓣比≤20 dB,经过该方法校正后带内相位达到≤±5°的水平,距离门内主副瓣比达到≥28 dB的水平。

Inverse synthetic aperture radar (ISAR) is mainly applied to the radar stationary but the target motion scene, can obtain the high-resolution two-dimensional image. In ISAR system, image degradation is induced if big nonlinearity of amplitude and phase of ISAR make the data defocus. In this paper,a corrective method of some ISAR system's phase nonlinearity is proposed. In the system original phase fluctuation of in-band is about 800 degree and the ratio of mainlobe peak to sidelobe peak is less than 20 dB in the distance door when tracing the space station. After using this corrective method the phase fluctuation of in-band is less than plus-minus 5 degree and the ratio of mainlobe peak to sidelobe peak is more than 28 dB in the distance door.