Advanced multi-pass InSAR imaging for surface deformation studies

This paper describes a multi-pass InSAR imaging approach for surface deformation studies. Such a technique extends concept of SAR tomography (TomoSAR) based on multi-pass InSAR data, in order to produce deformation map in elevation domain and velocity domain, respectively. Compared to conventional InSAR method, multi-pass InSAR imaging technique acquires multi-baseline information and allows reconstruction of multiple scattering sources in Tomo-Doppler plane (Elevation-Velocity plane). This technique offers a solution to layover issue over conventional InSAR method, but it suffers from double-scattering problem. This paper simulates a phenomenon where double-scattering impairs the imaging process and an improved solution method to separate single and double scatters from inferring pixels. In real circumstance, there are still other interferometric issues such as phase ambiguities of noise and phase discontinuity. Thus, a phase-unwrapping method associated with an improved ordered-statistical filter is included for interferometry processing. An experiment based on real SAR data is set up to demonstrate this technique.