I am working on processing SAR scenes for a mountainous area, and the highest resolution DEM I have access to for the area is at 1 arc-second. The processing flow I’d like to employ is:
-Deburst -> Remove Thermal Noise (if applicable) -> Apply Orbit File -> Calibrate -> Speckle Filter -> Terrain Flatten -> Multilook -> Terrain Correct
As the DEM is of coarser resolution than the SAR scene, when I try to terrain flatten SNAP posts a warning that my DEM is of coarser resolution than the SAR scene and I should multi-look the product before Terrain Flattening.
As Small’s paper on flattening gamma focuses on radar geometry interacting with topography to influence both the radar cross section as well as returned brightness, I am curious how multi-looking will affect the accuracy of my Terrain Flattened brightness values. Does anyone have thoughts on the matter?
Thanks in advance,