Multi-temporal InSAR for deformation study (MInDS): A software for deformation monitoring

Multi-temporal SAR Interferometry (MT-InSAR) is one of the widely used modern geodetic techniques for monitoring the surface deformation. By using the spatio-temporal analysis of a stack of differential interferograms,  MT-InSAR measures the time series deformation pattern. The analysis separates the deformation component from decorrelation noise, atmospheric error, and inaccurately modelled nuisance parameters. In the initial phase of the development of MT-InSAR approach, only highly coherent pixels, called the persistent scatterers (PS), were used for deformation monitoring. Highly coherent pixels are mostly found either in the urban regions or on the slopes facing the satellite. To estimate the deformation pattern in other regions, moderately coherent pixels, called distributed scatterers (DS), are used. However, before applying spatio-temporal analysis to estimate deformation, the phase information of DS pixels needs to be optimized by the phase triangulation algorithm (PTA).

We have developed a software Multi-temporal InSAR for deformation study (MInDS), which uses a similar environment as stamps use.  The processing chain of the MInDS processing chain is based on Similar Time-series Interferometric Pixels (STIP), representing the number of neighborhood pixels with similar phase history. In this approach, PS selection and estimation of look angle error is improved by using STIP of the PS pixels. After the selection of PS, the PTA implemented by using complex least squares utilises the phase information of neighboring STIPs to improve the phase coherence of DS pixels. Finally, the deformation pattern of the PS and phase-optimized DS pixels are used for deformation estimation using spatio-temporal analysis.