COMET LiCSAR processing using Gamma SAR and Interferometry software on Sentinel 1 IW SLC products.

For the details of the LiCSAR methodology [LiCSAR: An Automatic InSAR Tool for Monitoring Tectonic and Volcanic Activities paper in the docs tab]. In summary, once a new acquisition arrives, it is logically decomposed into pre-defined burst units and registered in the LiCSInfo database that handles burst and frame definitions. Images including bursts that form a given frame are extracted and merged into frame images. These are coregistered towards a primary frame image (a master image) that was set during the initialization of a frame, beforehand. The coregistration process includes spectral diversity and other necessary corrections. Once coregistered, the interferograms are formed by combining the new image with three chronologically previous ones. This way is suitable for interpretation and for further use of the interferograms in multitemporal InSAR processing methods based on small baselines strategy (e.g. NSBAS approach currently implemented into custom LiCSBAS chain [ LiCSBAS: An Open-Source InSAR Time Series Analysis Package Integrated with the LiCSAR Automated Sentinel-1 InSAR Processor paper in the docs tab]). The interferogram unwrapping is performed using optimised SNAPHU approach. All the LiCSAR products are multilooked by factors of 5 in the range and 20 in the azimuth directions to achieve a resolution of around 100×100 m per pixel.

LiCSAR processing chain consists of:
1. Preparation of Frame Epoch SLC
2. Resampling to RSLC
3. Formation of Differential Interferograms
4. Unwrapping Interferograms
5. LiCSInfo Metadata Database
6. LiCSAR FrameBatch Processing
7. FrameBatch Processing Chain
8. FrameBatch Post-Processing

For more information please see the LiCSAR: An Automatic InSAR Tool for Monitoring Tectonic and Volcanic Activities paper in the docs tab.