虚拟孔径天线配置及其成像性能研究

Study on Antenna Configuration of Virtual Aperture and Its Associated Imaging Performance

合成孔径雷达可以获取2维高分辨雷达图像,但只能工作在侧视模式,不能进行前视成像,也不能对静止和运动目标同时聚焦。针对上述雷达成像中的新问题,基于多发射多接收原理的虚拟孔径是一条有效的解决途径。该文研究了虚拟孔径成像中的天线配置及成像方法,比较了不同天线配置下的直线虚拟孔径成像性能。从理论上证明了两个发射单元分别置于接收线阵两端是一种有效的直线虚拟孔径天线配置方案,推导了这种天线配置下的成像分辨率解析表达式,并通过实测数据进行了验证。

Synthetic aperture radar can obtain two-dimensional high resolution radar images, but it has to work in side-looking mode without forward-looking imaging capability, and can not focus stationary and moving targets simultaneously as well. Virtual aperture on the multiple-input multiple-output theory is an efficient solution to the aforementioned new problems of radar imaging. In this paper, antenna configuration and associated image formation of virtual aperture imaging are studied. Linear virtual apertures of different antenna configurations are compared in terms of imaging performance. It is theoretically proved that two transmitting elements are placed on the ends of received array is an efficient antenna configuration scheme to form a linear virtual aperture. The analytical expression of imaging resolution of this antenna configuration is derived, which is also validated with real data.