Research Of Estimation Of InSAR Baseline

Synthetic aperture radar interferometry (InSAR) has been developed in 1960's. It records amplitude and phase information in every pixel of the SAR image. Combining radar system parameters and basing on strict geometry, the three dimensionin formation and height change of the terrain can be precisely extracted. InSAR results have many advantages such as high precision, high resolution, unlimited to weather, wide area imaging and so on. According to these advantages, InSAR is widely used in topographic mapping, deformation monitoring, resource in vestigating etc.Baseline is an important parameter in synthetic aperture radar interferometry. Slight errors of baseline length and orientation would result in large terrain height error.For a two-pass InSAR system, the parameter of baseline will change during the flying. And it should be estimated differently. The common way for calculating the Baseline is based on the DEM. Unfortunately, DEM is always difficult to obtain. To use the available data fully, this paper first calculates the baseline by the geometry of orbits.Experiment results in this paper indicate that the precision of three dimension baseline estimation algorithm based on satellite ephemeris mainly depends on the precision of satellite ephemeris, earth model and rangvariance. The three dimension baseline estimation algorithm based on satellite ephemeris can be used in areas without ground control points or auxiliary DEM data. To promote the precision of DEM, this paper analysises a method of baseline estimation - Konecny Radargrammetric Image Processing method.