通过对地球同步轨道（GEO）卫星运动特点的分析，阐明其对多普勒分辨率的影响。传统的双基合成孔径雷达（SAR）多普勒分辨率表达式由于不考虑雷达平台加速度矢量带来的影响，并不适用于GEO星弹双基SAR系统。根据收发平台的双曲线轨迹对目标的回波多普勒特性影响，首先利用梯度方法推导了GEO星弹双基SAR系统的多普勒分辨率表达式；随后详细地分析了GEO卫星与导弹的空间几何关系及多普勒参数，特别是加速度矢量对多普勒分辨率的影响。仿真结果验证了所推导多普勒分辨率表达式的有效性，其有助于双基SAR理论系统完整性的提高，为后续系统设计及应用实践提供理论支撑。
By analyzing the motion characteristic of Geosynchronous Earth Orbit (GEO) satellite, the influence of GEO satellite on Doppler resolution is expounded. Without considering the acceleration of the platform, the expression of Doppler resolution of traditional bistatic Synthetic Aperture Radar (SAR) cannot be applied directly to geosynchronous-missile bistatic SAR. Firstly, based on the influence of curve trajectories of transmitter and receiver on Doppler characteristic of echo signal, the expression of Doppler resolution for geosynchronous-missile bistatic SAR is deduced with the gradient method. Then the impacts of geometrical configuration and Doppler parameters (especially the acceleration) on the Doppler resolution calculation are discussed in detail. Finally, the simulation results validate the proposed method for calculating Doppler resolution of geosynchronous-missile bistatic SAR. And this could increase the integrality of bistatic SAR theory system and provide theoretical support for the system design and application of bistatic SAR.
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