The CSL InSAR Suite Processor: Specificities of a Command Line InSAR Processing Software Specifically Adapted for Automated Time Series Processing

LIBERT, LUDIVINE; ORBAN, ANNE; SAMSONOV, SERGEY; BARBIER, CHRISTIAN; D'OREYE, NICOLAS; DERAUW, DOMINIQUE; KIRKOVE, MURIELLE; FRANÇOIS KERVYN

Milano

Simposio; Living Planet Symposium; 2019

European Space Agency

Being part of the ESA Fringe group since its very first meeting in October 1992, the Centre Spatial de Liege (CSL) has a long-standing experience in the frame of SAR processing and SAR interferometry. Through numerous projects mainly funded by the Belgian Science Policy (BelSPo) and ESA, the CSL Signal Processing Laboratory has developed numerous tools now known as the CSL InSAR Suite (CIS).CIS, as all tools of its kind, allows performing all processing steps for InSAR, DInSAR, PolSAR, PolInSAR, ? including geoprojection of results in raw or ENVI format.Additionally, it is a command line processor (coded in C language) having its own peculiarities:- It allows handling most of the former and currently available sensors (ERS, ENVISAT, RADARSAT 1 & 2, TanDEM-X, TerraSAR-X, ALOS, CosmoSKyMed, Komsat-5 and Sentinel-1 A&B),- In addition to Snaphu, it includes two homemade phase unwrapping processors,- It allows performing Split Band interferometry (e.g. for absolute phase unwrapping or ionospheric phase screen estimation) and spectral coherence measurements,- It allows masking the interferometric products before unwrapping based on masks provided in geographic coordinates to avoid perturbations due to low coherence areas,- It incorporates tools for interpolation of small gaps and residual phase plane removal,- It allows pixel coherence tracking.With respect to Sentinel,- It allows reading and processing only selected bursts encompassing the area of interest, or even cropping a region of interest within the burst(s) based on a kml file, to limit processing time- For zone of interest that would span more than one image, it performs automatically the stitching of all the required images to cover in a single scene the desired footprint (provided by a kml file)- Its high precision orbitographic computation allows performing Sentinel1 data coregistration without requesting Extended Spectral Diversity processing.In many aspects, each modular InSAR processing function was fine-tuned and optimized to ease its full automation through shell scripts (see d?Oreye et al., this session) allowing to process all modalities (ascending and descending orbits, vertical and horizontal polarizations, whatever the satellite, the wavelength and the ground based resolution) from the reading of raw images up to the InSAR pair selection and the generation of differential phase, displacement, amplitude, coherence? layers in geo-projected coordinate system.New modalities may be added as they come to extend the time series.We will present some CIS specificities thit a powerful tool, specifically for ? but not limited to - (M)SBAS processing (see Samsonov et al., this session). In particular, it allows referencing all SAR data of a given modality to a single super master image and performing (D)InSAR processing of all pair in the geometry of this super master.Differential phase layers are then sent to the MSBAS processor to generate or update displacement time series, allowing to perform near real time monitoring of natural or anthropogenic ground deformation.In this presentation, we will review the above-mentioned specificities and show some examples issued from full automation like:- Vertical and horizontal MSBAS ground deformation results,- time series analysis of shadow measurements for lava-lake leveling- time series coherence analysis.