The Potentials of L-band SAR Satellites for Measuring Azimuth Deformation

Along-track (approximately north-south) deformation is critical in constructing three-dimensional deformation with synthetic aperture radar (SAR) satellites orbiting the Earth in sun-synchronous polar orbit. The problem of measuring along-track deformation with short-wavelength SAR data is decorrelation. A fleet of newly launched and upcoming long-wavelength L-band SAR satellites bring new opportunities to achieve this goal. We analyze the possible methods that can be used to measure along-track deformation considering the significant impacts of the ionosphere on L-band data. We evaluate the performance of some selected L-band SAR satellites. The results show that along-track deformation with decimeter precision at kilometer resolution can be measured by multiple-aperture InSAR (MAI) with ionospheric corrections. Time series analysis of corrected MAI interferograms reveals the postseismic deformation of 2016 Kumamoto earthquakes in Japan. The performance of time series analysis is expected to be improved with future L-band SAR missions that have much higher duty cycles.