主星带辅星群干涉SAR编队设计的约束条件

针对主星带辅星群干涉SAR的星载双站、斜视、空间基线等特点,从系统工作过程和测高性能分析角度出发,分别对主星带辅星编队干涉SAR编队设计的几个变量(主星与辅星群的距离、基线的长度和指向角)提出设计约束条件。对辅星回波时序、信噪比进行分析,得到主、辅星间距离设计的约束条件;对干涉测高精度进行分析,重点考虑空间基线去相关对干涉相位误差进而对测高精度的影响,给出基线长度和指向角与干涉测高精度的关系,得到基线长度和指向角设计的约束条件。仿真分析表明,由于干涉车轮和干涉钟摆编队是基于正侧视干涉几何提出的,它们的测高性能不是最优的。

Restriction of Spaceborne Multistatic InSAR Formation Configuration Design

The formation configuration design of distributed spaceborne interferometric SAR(DSInSAR) is key issue of system design.It must be combined with the flow of work and function of system.Because of its features of multisatic,squint angle and spacial baseline,spaceborne(multisatic) InSAR system must be analysed by new signal processing and performance evaluating methods.New restrictions of formation configuration design also must be put forward.Improved interferometric signal processing and performance evaluating methods are researched.Based on these new methods,restrictions of destance between master satellite and assistant satellites(formation),spacial baseline vector are presented.Distance restriction is based on analysis of bistatic radar SNR and time series.Spacial baseline vector restriction is based on analysis of DEM precision.Spacial baseline decorrelation which influence the interferometric phase error and DEM precision is analysed in detail.The quantitative and qualitative relation of spacial baseline vector,spacial(baseline) decorrelation,the intrferometric phase error and DEM precision is presented.Because(interferometric) Cartwheel and Pendulum formation is put forward based on side-glance geometry,simulation results show that the DEM performance of them are not optimal.