针对主星带辅星群编队InSAR的双站、斜视、空间基线等特点，首先建立绝对测高误差与相对测高误差模型；重点分析了基线去相关对干涉相位误差的影响；对干涉车轮和钟摆编队的测高性能、对测高精度与基线矢量的关系进行仿真分析；其次与两种经典近似几何关系下的测高精度分析进行对比。仿真结果表明：干涉测高精度必须考虑基线去相关的影响；相对测高精度明显优于绝对测高精度；经典近似几何给分析测高精度带来很大误差。

Based on bistatic,squint and spatial baseline characteristics of spaceborne parasitical interferometric synthetic aperture radar(InSAR),models of absolute and relative digital elevation model(DEM) errors are set up.The influence of baseline decorrelation imposing on interferometric phase error is analyzed in detail,which is an important influence of DEM error.The absolute and relative DEM performance of interferometric Cartwheel and Pendulum are simulated.The relation of absolute and relative DEM accuracy with baseline vector are simulated too.Two classical approximate geometries including side-glance and identical range-elevation plane geometries are analyzed.The absolute and relative DEM accuracy of them are compared with those of actual geometry.The simulation results show that baseline decorrelation must be considered in DEM accuracy analysis of spaceborne parasitical InSAR,relative DEM accuracy value is prior to absolute DEM accuracy value,the classical approximate geometry bring great errors which cannot be neglected.