Duel polarization image decomposition

[saeedpurakrami]

hello every one,
I apply H Alpha duel pol decomposition on sentinel SLC vv/vh image with this steps.
split-deburst- subset my study area- apply orbit file- calibration(save in complex)- polarimetric filter (refined lee with 7*7 window size that output has 4 band contains c11, c12_real, c12_image and c22)- H Alpha duel pol decomposition- range dopller trrein correction.
range of alpha Between 22.13 to 88.6 and entropy Between 0.05 to 0.994 and anisotropy Between 0.087 to 0.989.
In this picture you can see the RGB color combination of entropy, anisotropy and alpha .

and this image you can see NDVI image

radar and optic images acquisition time is too close together.
this image is a flat agricultural region with Small and relatively large at about 1 ha farms. but in RGB color combination of entropy, anisotropy and alpha Nothing is unknown. when I classify stacked ndvi image with entropy, anisotropy and alpha overall accuracy Much less than alone NDVI classifying .
Is it due to the small size of farms is decreasing classification accuracy?
Is there a flaw in my analysis steps?

[ABraun]

what SAR data are you using?

Polarimetric decomposition works better when you have quad-pol data (HH HV VH VV).
This paper discusses how the parameters change with dual-pol data:
http://earth.esa.int/workshops/polinsar2007/papers/75_cloude.pdf

The decrease of information content could be due to this limited decomposition quality but also of the lower spatial resolution.

Maybe this is also helpful for you:

H-Alpha Plane Problems

@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…

[saeedpurakrami]

thanks for your reponse.
I use sentinel 1 duel polar image (vv/vh).
I want to know that my steps for decomposition is true?

[ABraun]

the earlier you apply the orbit file the higher is the chance that your co-registration is of good quality. So I would personally move that step to the beginning. The rest seems fine to me.

[saeedpurakrami]

@ABraun

the earlier you apply the orbit file the higher is the chance that your co-registration is of good quality. So I would personally move that step to the beginning. The rest seems fine to me.

thank you for your guidance.