InSAR中基线精度要求的探讨

Discussion about Requirement of Baseline Precision in InSAR

基线是合成孔径雷达干涉测量中的一个重要参数。基线长度和倾角的微小误差,都可能引起大幅度的地形高度误差。根据测量相位不定性引起的高度误差,分析了垂直基线与地形高度灵敏度的关系,并推导了垂直基线与高度模糊数的关系式。通过基线长度和倾角不定性引起的高度误差,分别估算了InSAR对基线长度和倾角精度的要求,并给出了高度估计误差对基线误差的灵敏度,最后通过ERS数据进行了仿真,并得出了三点结论。

Baseline is an important parameter in synthetic aperture radar interferometry. Slight errors of baseline length and orientation would result in large terrain height error. This paper analyzes the relationship between perpendicular baseline and terrain height sensitivity firstly, based on height error induced by uncertainty of phase. And the expression of relation between perpendicular baseline and the height of ambiguity is obtained. Depending on the height error induced by uncertainty of baseline parameters, the requirement of baseline length and orientation in InSAR are approximately calculated respectively. Furthermore, sensitivity of height estimated error to baseline error is got. Finally simulation is done on ERS data and conclusion is obtained.