Is there a method by which I can transform my sentinel 1 images to create new images, like we do band ratios and spectral indices with optical data? I tried to fuse sentinel 1 and sentinel 2 through PCA, but it looks like s-1 has very little loadings into my final PCs. I am not even sure if s-1 will contribute anything to the classification I want to perform.
You can use the Band Maths to create new Bands (menu: Raster / Band Maths).
In the Radar menu are many tools which can be applied to S1 data.
Before you try fusing S-1/S-2 products, I would run calibration and terrain correction on the S-1 data if you are using S1 GRD products. If you’re looking for something like optical band ratios but for SAR, you’ll need to research a little into polarimetric decompositions.
Thank you very much. With regards to image preprocessing I performed; Apply orbit file -> Radiometric calibration ->Speckle filtering -> Geometric correction (terrain correction)…-> Linear to db -> conversion to band -> resampled the channels to 20m -> and then aligned them with Sentinel 2 images (UTM WGS84 Zone ##) …I hope I performed preprocessing appropriately