An empirical model for measurement accuracy of along-track deformation by advanced multiple-aperture SAR interferometry from COSMO-SkyMed dataset

Despite several studies using the multiple-aperture interferometry (MAI) technique, X-band SAR has rarely been applied to MAI-based studies due to their shorter decorrelation timescale. However, the relatively short antenna length and high temporal resolution of the COSMO-SkyMed X-band SAR system provides an opportunity to measure the precise displacement in the along-track direction. In this study, we have assessed the MAI performance in comparison with GPS and established an empirical uncertainty model of MAI measurements with respect to interferometric coherence. It enables us to confirm the difference between theoretical and practical uncertainties of the MAI method. Moreover, this study will be helpful for evaluating the reliability of MAI measurements where GPS data are unavailable.