基于波束空间的SAR阵列天线波束展宽方法

针对合成孔径雷达（SAR ）天线设计过程中,难于获得均匀幅度和较宽的照射区域,实现灵活多变的波束变换的问题,提出一种基于波束空间阵列天线波束展宽的方法.通过将平面阵列天线分成多个子阵列,以子阵列为单位设计出基本波束,再通过幅度和相位加权使各子阵波束在空中实现同相移位叠加,从而实现波束覆盖区域的控制.由于各子阵可作为基本单元来处理,只需对各子阵实行加权,即可极大地降低阵列导向矢量的数目,能灵活地设计各种波束图,实现指向控制和干扰抑制.仿真实验的结果证明了该方法的正确性和有效性.它可用于单波束发射多波束接收(SIMO)与多波束发射多波束接收（MIMO）等新的SAR成像体制中.

Investigation of SAR array antenna beam broadening based on beam pattern space

In the antenna design process of synthesized aperture radar (SAR) system, it is difficult to get wide beam and uniform irradiating amplitude, and not flexible to change beam pattern. A design method of SAR array antenna beam broadening based on beam pattern space was given out. The planner array antenna is divided into many sub arrays, and then the preliminary beam pattern is designed from sub array; after amplitude and phase being weighted, each sub array has the same beam pattern and added together with space shift to perform the desired covered region pattern in same phase. For the process is based on sub array, it only needs to consider the weighty of sub array. The results greatly decrease the amount of manifold vectors. This novelty makes it easy to design variable beam pattern, control beam direction and suppress interference. The simulation results verified the correctness and validity. This method can be used in the new concept SAR system as single input with multiple output (SIMO) or multiple input with multiple output (MIMO) SAR.