ALOS PALSAR Projection

Microwave Toolbox
#1

I am attempting to use ALOS-PALSAR L1.5 data from the ASF, however, when trying to load the data into another visualization software (i.e. ArcMap) the projection appears to be missing. This occurs when loading the .img file from the SNAP output.

Basic preprocessing steps were to calibrate to sigma naught and perform speckle filtering. I also downloaded the RTC data from the ASF, however, this data is gamma-naught calibrated and I would like to use sigma-naught.

Any recommendations on how to ensure the data remains projected when reading it with other software would be appreciated.

#2

Level-1.5 products are not fully geocoded. I recommend downloading Level-1.1 data, applying calibation, filtering and Range Doppler Terrain Correction and then load the img into ArcMap.

ASF also provides analysis ready (RTC = radiometrically terrain corrected) products in many cases.

#3

Thanks for your reply.

Unfortunately, Level-1.1 data is not available for the data formats that cover my area of interest through the ASF - is there another source you might recommend for downloading the data?

I did look at the RTC data, however, it is gamma-naught calibrated and other data that I have is sigma-naught.

#4

I thought L1.5 products are always accompanied by L1.1 products at ASF…

Gamma0 from ASF is produced by Radiometric Terrain Flattening on SNAP and only differs from Sigma0 at slopes.

#5

My area also lacks L1.1. There is L1.0 or L1.5.