星载双天线干涉SAR基线高精度测定

星载干涉合成孔径雷达(InSAR)基线的高精度测定是获取地面数字高程信息的关键技术,针对双天线InSAR系统,采用光学系统测量和激光测距联合法。其中,光学系统用于测量基线指向,根据3点T型标志点,给出近似解析解确定算法;由于光学成像测量在相机视轴方向精度不高,需采用激光测距方法,通过信号混频FFT检测相位,最终确定基线长度。模拟结果显示,光学测量与激光测距相联合可高精度确定干涉基线矢量。

High Precision Measurement of Spaceborne Dual-antenna InSAR Baseline

High precision measurement and determination of spaceborne InSAR baseline is a key technology in the acquirement of digital elevation information.The optical measurement and laser range finder were applied to the dual-antenna INSAR system.The orientation of interferometric baseline was measured by the optical system.Based on the three T-type targets,approximate analytic solution was obtained.However,since the precision of solution was low in the axis of sight,the laser range finder was proposed,which could derive the length of baseline by the detection of phase after signal mixing with the application of FFT.Simulations conducted show that the vector of interferometric baseline could be precisely determined by the combination of optical measurement and laser range finder.