ABraun
November 29, 2018, 3:20pm
28
there are some decompositions which also work for Dual-polarized data but the results are not very good.
@agw2
No, sorry. As I started this discussion here, I tried to use the zones in SNAP for doing a classification. Then I realized that the result of the classes didnt fit to the zones. I thought that it is a problem of the SNAP program, but it isnt. I figured out that the H/Alpha Classifier in SNAP is not intended for the SENTINEL 1 SLC Data. It is made for Quadpol Data like Radarsat.
So the Problem is, that the H/Alpha Classification in SNAP based on the entropie and alpha (thats fine) but th…
technically, you can derive entropy and alpha, yes. But the results are not very useful, especially for cross polarization. It just doesn’t give all the information needed for polarimetry:
Thus, HH-VV SAR is a suitable alternative to full-polarization SAR in certain cases. Meanwhile, the extraction performance of the other two dual-polarization SARs is badly degraded due to the lack of co-polarization. Therefore, HH-HV and HV-VV SARs cannot effectively extract the scattering mechanisms in the …
most of the decompositions require 4 polarizations: HH, HV, VH and VV.
However, most of the Sentinel-1 data in IW mode is in only one or two polarizations:
There are studies which apply decompositions on dual polarized SAR data:
You can chose the Entropy-Alpha Dual Pol Decomposition for a try.
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It is discussed in other topics if it makes sense: