Terminology

Acquisition

The date of SAR acquisition or image, expressed as a datetime.datetime object.

Pair/Pairs

A pair is a combination of two SAR acquisitions in acquisition order.

Note

In FanInSAR, pairs will be ordered automatically.

Loop/Loops

A loop contains a list of edge pairs and one diagonal pair. See paper [1] for more details.

TripletLoop/TripletLoops

triplet loop is a special loop that contains three pairs. See paper [1] for more details.

CRS

A coordinate reference system (CRS) is a coordinate-based local, regional, or global system used to locate geographical entities. In FanInSAR, the CRS is handled by the rasterio and pyproj packages. A valid CRS input for FanInSAR can be any type supported by the pyproj.crs.CRS.from_user_input() method.

[1] (1,2)

: Fan, C., Liu, L., Zhao, Z., Mu, C., 2025. Pronounced underestimation of surface deformation due to unwrapping errors over tibetan plateau permafrost by sentinel-1 InSAR: identification and correction. J. Geophys. Res.: Earth Surf. 130, e2024JF007854. https://doi.org/10.1029/2024JF007854