Advantages and Limitations of Forward Squint SAR In Single Pass Interferometric Mapping Of Topography

In our paper we discuss advantages and limitations of original alternative interferometric scheme of topography mapping with one-pass single-antenna forward squint synthetic aperture radar (SAR). Key specificity of the new interferometric scheme is in forward/backward squint geometry of SAR observations, where interferometric baseline is formed thanks to observation of the surface from two points displaced along the orbit in azimuth direction. A comparison with classic scheme of interferometric observations is made and it is shown that in the new scheme the sensitivity of interferometric phase to topography variations is dependent on squint angle and interferometric baseline. The interferometric baseline length is limited by acceptable level of coherence, which is dependent on Doppler centroids decorrelation and decorrelation because of scene rotation.