中文摘要：

收发平台的波束同步是关系到星机双基地SAR能否具有实用价值的核心技术．已有学者提出一种基于收发波束指向控制的同步方法，但原方法中所做的一些假设影响了其实用性．本文给出了两种方法．第一种方法去掉了原方法中所做的几条假设．给出了改进后的数学模型．第二种方法充分利用系统“远发近收”的特点，采用宽波束照射，能在方位分辨率相等的前提下获得比第一种方法更长的场景长度．分析了两种方法的优缺点及各自适用场合．

英文摘要：

The biggest challenge in the development of spaceborne/airborne hybrid bistatic synthetic aperture radar,abbreviated as SA-BSAR in the text,is the beam synchronization of the antenna footprints. A method by performing beam steering on both sides has been reported in some published literature. There are,however,in the existing method, some assumptions that significantly limit its practicability. Two methods are given and validated. In the discussion of the first method, a modified mathematical model is presented to cancel those assumptions. The second method transmits a very wide beam in azimuth making use of the characteristic of the receiving distance in SA-BSAR is much shorter than the one in spacebome SAR systems. The second approach provides, with the same azimuth resolution, a longer scene extension than the length achieved by the first approach. Advantages and disadvantages of each method are discussed and the applicable ranges for each method are also analyzed.