We have to first export the .tif file from the SNAP. After that just apply this code. Just play with the color map according to the histogram of the image.
ABHILASH SINGH (2020). Sentinel 1A image reading and displaying in MATLAB (https://www.mathworks.com/matlabcentral/fileexchange/73073-sentinel-1a-image-reading-and-displaying-in-matlab), MATLAB Central File Exchange. Retrieved .
Thanks @FSh for letting me know your problem. I will try to add the projection part. Meanwhile you just fixed the aspect ratio and complete your processing. Afterwards just georeference the final image.
Thank you, but the problem is the projection, which is UTM and never matches the other projection