摘要
设计和完成了一套微波成像系统。根据反雷达伪装微波成像的应用需求,系统采用阶跃调频连续波体制和合成孔径技术,可实现对外场全尺寸伪装目标的高分辨二维成像。传统FFT成像方法计算过程比较简单,但分辨率低,图像相对比较粗糙,对50米远处目标的二维分辨率仅能达到0.5m×0.5m。非线性空间谱估计(DOA)即超分辨技术可大大改善在系统带宽内处理空间信号的估计精度和分辨率。随着该技术的日益完善,近年来被广泛应用于雷达成像领域,用来提高距离和方位分辨率。2D-RELAX算法是较易实现的一种精度高、鲁棒性好的超分辨算法。通过对某型伪装示假目标的成像结果表明,在同样的硬件条件下,其对分辨率确有较大改善,可以达到0.25m×0.25m,接近系统分辨率的理论最小值,图像也较精确。
A set of microwave imaging system is Designed and developed based on synthetic aperture radar (SAR). According to the application demand of anti-radar disguise microwave imaging, stepped frequency modulated (FM) continuous wave(CW) and synthetic aperture technique are adopt to realize out-field dimension camouflage target 2-D high resolution imaging, For traditional FKF imaging method, its computing process is relatively simple, but the resolution is quite low, and the image is comparatively roughness. The resolution of target from 50 meter can only reach 0.5m ×0. 5m. Non-linearly direction-of-arrival (DOA), also known as super-resolution can greatly improve estimation precision and resolution, Since this technique 's increasingly perfection, in recent years, it is widely used in radar imaging field to improve range and azimuth resolution. 2D-RELAX algorithm is a super resolution algorithm which has high precision, good robust and it is easy to realize. Through definite experiment, the results of camouflage target show that under same hardware conditions it can greatly improve resolution which can reach 0.25m×0. 25m approaching to system theoretical resolution and the radar image is comparatively precision.
出处
《微波学报》
CSCD
北大核心
2009年第5期10-15,共6页
Journal of Microwaves