星载双基地SAR干涉测高误差分析

针对星载双基地SAR干涉测高的新特点,给出了“空间基线”、“变基线”下的干涉测高原理,建立了绝对高程误差模型和相对高程误差模型。从提高测高精度、优化系统设计的角度出发,分析了相对高程和绝对高程测量精度受基线形式的影响,给出具有一般性意义的测高误差关于空间基线姿态的二维分布全貌图,分析了图中误差极点走廊和两类优良点的位置和相应的物理意义。将误差分布图用于指导辅星相对轨道设计,证明了该图对基于测高性能的辅星轨道优化设计具有重要意义。

Analysis on the height measurement error of spaceborne bistatic SAR interferometry

Principle of height measurement of InSAR in spaceborne bistatic SAR system is given under "solid baseline" and "variational baseline", based on which the error models of absolute height and relative height measurement are built. The influence of the baseline attitude on the measurement accuracy is analyzed and a profile which describes the relationship between height measurement accuracy and baseline attitude angles is given. A 'bad' band and two kinds of 'good' points on the profile are presented and analyzed in detail. The profile is used to guide the design of auxiliary satellite's relative orbit and is proven to be useful for InSAR performance optimization.