高重频频率步进雷达的杂波抑制和高分辨处理

Clutter Cancellation and High Resolution Processing in HPRF Stepped-frequency Radar

充分利用多个频率步进周期的回波,提出一种类似MTD原理的同频去杂波方法,从频域上有效分离杂波并加以剔除,再反变换恢复时域波形。运动补偿后相参积累,最后脉压得到一维高分辨距离像。文中给出了关键参数的设计原则,仿真并分析了慢时间内目标运动对成像的影响及所需的速度补偿精度。研究表明,该方法不受限脉宽频率步进阶梯积的取值,即使目标和杂波在距离像上混叠,它仍能在强杂波、低信噪比情况下取得很好的检测性能和成像效果。

A novel algorithm for cancelling clutter similar to MTD principle, via DFT between the returns of these pulses with same carrier frequency in different bursts, is proposed to separate targets and clutter in frequency domain. All modified data after motion compensation are integrated to improve the SNR, then HRRP of moving target can be achieved by IFFT transform. The design rules of key parameters are put forward, and the influences of target motion or the required precision for motion compensation during slow time are analyzed and simulated in detail. The results show that, the method isn＇t limited by the product of pulse width and frequency step size. Even if the target is masked by the clutter in range profile, it can also obtain both high detection performance and fine HRRP with lower SCR or SNR.