Error in c2 matrix values of Sentinel-1 data

Microwave Toolbox
#1

Dear marpet have a look…

Hi all,
I have processed Sentinel-1 (VV/VH) IW-SLC product in SNAP 6.0.
Steps were:
S1-TOPS-Spilt–>Radiometric Calibrate (saved as complex) -->S1-TOPS-Deburst–>Multilooked–>Polarimetric Matrix (c2) generated

Now the C11 values are lower than the C22 values for most of the pixels for different classes.
Usually, in dual-pol (c2) matrix, c11 correspond to VV and C22 correspond to VH component, hence c11 values should greater than c22. Whereas in SNAP c2 matrix generation it is happening in reverse way. This will affect the further polarimetric processing.

Does anyone checked this kind of issue?

And if we look directly the intensity/backscatter values, they are proper…ie VV values are higher than VH values.

#2

I think in SNAP, the c11 element in the dual-pol covariance matrix corresponds to VH and c22 corresponds to VV for (VH, VV) polarization because the scattering vector is given as k = [svh, svv]^T.

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