凝视数字多波束合成孔径雷达原理

针对传统合成孔径雷达在实现高分辨大测绘带(简称高分宽幅)成像中存在的问题,文中将数字波束形成技术和合成孔径雷达结合,提出凝视数字多波束合成孔径雷达的概念。首先,将成像区域在距离和方位向分割为多个子区域进行独立成像,避免传统合成孔径雷达在高分宽幅成像领域的设计限制;然后,利用数字波束形成技术对天线阵面所有接收单元进行数字加权,在方位向和俯仰向形成多个高增益的接收窄波束,并控制接收波束实现对每个子区域的凝视观测,延长合成孔径的长度,提高成像分辨率。仿真表明,凝视数字多波束合成孔径雷达可以有效突破传统合成孔径雷达系统设计上的瓶颈,实现高分宽幅成像。

The Principles of Staring Digital Multiple Beam Synthetic Aperture Radar

In this paper, an innovative imaging concept of staring digital multiple beams synthetic aperture radar (SAR) is presented for overcoming the shortcoming of traditional SAR in high-resolution wide-swath imaging. Staring digital multi-beams SAR is the combination of the digital beam-forming (DBF) technology with the principle of SAR. For avoiding the restriction in the traditional one, the new imaging concept in this paper divides the imaging area into several sub-patches to imaging independently. In additional, the multiple narrow receiver beams in elevation and azimuth are formed by whole elements in antenna aperture and DBF, and the steering of multiple beams is controlled to achieving the staring observation, which can extend the length of synthetic aperture to improve the resolution of imaging. The simulation shows the staring digital multi-beam SAR can break though the limitation in the tradition SAR effectively, and achieve the high-resolution wide-swath imaging.