宽带Radon-Fourier 变换及基于CZT快速实现方法研究

宽带脉冲体制雷达中,脉冲尺度伸缩效应(PSE)和目标跨距离单元走动(ARU)问题会降低脉冲相参积累性能,进而降低微弱目标检测能力.为了解决PSE和ARU问题,文中给出一种宽带Radon-Fourier变换(WRFT)及其快速实现方法.首先设计了宽带匹配滤波器,然后通过联合搜索速度与距离参数空间,同时进行脉间相位补偿、宽带匹配滤波以及跨距离单元走动补偿,进而实现长时间脉冲相参积累.针对WRFT中参数空间遍历搜索带来大运算量问题,进一步给出了基于Chirp-Z变换(CZT)的快速实现方法.最后,数值实验验证了该方法的有效性.

A Study on Wideband Radon-Fourier Transform and Its Fast Implementation Based on CZT

In wideband pulse radar system, the performance of coherent integration can be deteriorated by the pulse scale effect(PSE) and the across range unit (ARU) phenomenon, and the weak target detection ability will be further decreased. To address these two problems, a wideband Radon-Fourier transform (WRFT) is given. First, the wideband matched filter is designed. Then by jointly searching the velocity and range parameter space, the inter-pulse phase fluctuation and the ARU effect can be well compensated and the wideband matched filtering process can also be operated simultaneously, and the long-time coherent integration can be further realized, based on which the weak target detection performance can be improved. Furthermore, to decrease the large computation burden caused by ergodic search in WRFT, a fast implementation based on Chirp-Z transform (CZT) is given. Finally, detailed numerical experiments are provided to demonstrate the effectiveness of the proposed method.