An Efficient Global Scale Sentinel-1 Radar Backscatter and Interferometric Processing System

Abstract

We describe an efficient and cost-effective data access mechanism for Sentinel-1 Terrain Observation with Progressive Scans (TOPS) mode bursts. Our data access mechanism enables burst-based data access and processing, thereby eliminating the European Space Agency’s (ESA’s) Sentinel-1 Single Look Complex (SLC) data packaging conventions as a bottleneck to large scale processing. The pipeline throughput is now determined by the available computation resources and the efficiency of the analysis algorithms. For targeted infrastructure monitoring studies, we are able to generate coregistered, geocoded stacks of SLCs for any area of interest (AOI) in the world, in a few minutes. In addition, we describe our global scale radar backscatter and interferometric products, and associated pipeline design decisions that ensure geolocation consistency across the suite of derived products from Sentinel-1 data. Finally, we discuss the benefits and limitations of working with geocoded SLC data.

Contextual Uncertainty Assessments for InSAR-Based Deformation Retrieval Using an Ensemble Approach

“…Each scene is stored as a GeoTIFF. The details of the coregistration process can be found in Agram et al (2022). Note that this cost will be present for any InSAR pipeline, and this cost is shared between the two InSAR methods being assessed, since these data are reused.…”

Radiometric Terrain Flattening of Geocoded Stacks of SAR Imagery

“…GTC products have been geolocated precisely [9] but have not been corrected for terrain-related radiometric effects. While we provide mathematical expression for working with different calibration levels of GTC products, we specifically focus on σ 0,E GTC products, which we process at Descartes Labs at a global scale [10].…”

“…For all examples presented in this section, we consider a facet located at near-range of the imaged swath as the impact of change in imaging geometry decreases with slant range [19]. We also specifically consider the transformation of σ 0,E GTC products to γ 0,T as this is most relevant for use with our global scale radar backscatter product [10]. This analysis can be easily extended in the same framework to study transformation of β 0 and γ 0,E GTC products.…”

“…We consider a stack of 58 acquisitions corresponding to a single Sentinel-1 burst footprint with European Space Agency (ESA) identifier IW1-0151226 (Descartes Labs identifier [10] 071-2637-IW1-VV-RD) over Big Bear, California in the USA and spanning the time period of January 1, 2020 to January 1, 2021. The perpendicular baseline variation of this stack is about 200 meters.…”

“…In the context of this manuscript, we specifically refer to GTC products generated on a common grid from interferometrically compliant acquisitions as a geocoded stack, unless mentioned otherwise. Such products are usually labelled with a common Path-Frame identifier (ERS, ALOS etc) or unique burst identifiers (Sentinel-1) [10,12]. These identifiers represent unique imaging geometry configurations, i.e., all images in the collection share baselines of less than a few kilometers with respect to each other and are acquired at similar incidence angles.…”