Terrain correction with a external DEM brings to the corrected S1 level curves phantoms

Hi, I downloaded a hi-res DEM (12.5 JAXA/Alaska facility) in FBS beam mode to terrain correct a S1 image, but the result is an image with some pixels that looks like a level curves of DEM in the final image. Is it the beam mode? or any parameters when I apply the terrain correction tool? Any thoughts?


The DEM file that is included with the Alaska Satellite Facility ALOS PALSAR RTC product .zip file is a copy of an open-source DEM that was downloaded, modified, and used to perform radiometric terrain correction (RTC) on an ALOS PALSAR granule. The height values of the modified DEM differ from the source DEM because an ellipsoid correction was applied before it was used for RTC. These files are not intended to be used in place of a standard DEM product but are included to assist in interpreting/evaluating the RTC products.

The sources of the DEMs downloaded and used for this project vary depending on the location of the PALSAR granule. Details about the DEMs used and the modifications applied are available here:

Note that the DEM file used for RTC is resampled to match the pixel spacing of the PALSAR source file, so the pixel spacing does not necessarily reflect the resolution of the source DEM.

General information about the ALOS PALSAR RTC products is available here: