结合数字波束形成技术,星载方位多通道合成孔径雷达(SAR)系统可以克服最小天线面积限制,实现高分辨宽测绘带(High Resolution and Wide Swath,HRWS)SAR成像。结合多站SAR系统即可实现高分辨干涉合成孔径雷达(Interferometric SAR,InSAR)地形测绘。该文通过分析星载多站模式下各接收通道接收回波的信号模型,推导得到了其相对于参考接收通道接收回波的通用相位补偿公式,该公式同时补偿了由沿航向和垂直航向基线引起的相位误差,然后对基于最优Capon法的多相位中心解模糊成像的保相性进行了分析证明,由此得到了解模糊后每个方位时刻回波所对应的卫星轨道信息,为后续干涉处理及目标定位等奠定基础,最后利用地球椭球模型仿真的星载双通道多普勒模糊回波数据验证了该文方法的有效性。
Incorporated with digital beamforming processing, along-track multi-channel spaceborne SAR systems are promising in High-Resolution and Wide-Swath (HRWS) imaging by overcoming the minimum antenna area constraint. In this paper, a common phase compensating equation for multi-static space-borne SAR systems is given. Then, it is proved that the optimum capon method can keep the phase quality, and the orbit parameters of each sample are obtained for the following SAR interferometry processing and target locating. Finally, the proposed method is validated using the simulated data based on the ellipse earth model.