针对TanDEM-X卫星计划,重点分析其在一个轨道周期内的测高性能的变化情况.首先从建立双星HELIX构形的HILL.方程出发,分析了一个轨道周期内直接影响干涉测高的有效基线,包括顺轨和交轨基线的影响,然后讨论了系统相关系数及其对干涉相位误差的影响,通过建立相对高程误差模型,进一步分析了系统相对高程精度.最后计算机仿真结果验证了分析的正确性.

According to TanDEM-X satellite program, this paper studies interferometric capabilities of TanDEM-X mission during an orbit period and tries to get the change of relative height error in a global scope. Firstly, based on HILL-equation of the helix formation, effective baseline, including the range and azimuth effective baseline, whichhas a great impacton interferometry is analyzed in detail during an orbit period. Then the influence of baseline decorrelation imposing on interferometric phase error is discussed detailedly, which is themost important influence on relative height error. At lastrelative heightmodel is established and relative heighterrororTanDEM-X system is presented further. The computer simulating result shows the validity ofanalysi