Hello! I have to compute the Radar Forest Degradation Index band math in SNAP, but I have just VH and VV bands. I need also HH and HV bands. Could you tell me if the other two can be obtained in SNAP starting from the ones I have? Thank you!
If H-polarisation is not sent by the satellite you do not have the HH and HV channels. You can probably assume HV=VH as that is true in most cases, but even with that approximation you are missing the HH polarisation.
RFDI compares the co-polarized response with cross-polarized response. I believe for Sentinel-1 you just use VV instead of HH and VH instead of HV.