Help with coherence maps for detecting mining activity


I am relativity new to working with SAR data, especially InSAR, so bear with me. I am trying to create coherence maps to detect changes associated with open-pit mining over a large area. I am using two images 12 days apart.

I think my maps are doing a reasonable job of showing some areas of change (Below is an example). However, it is very hard to identify amongst all the noisy low-coherence areas where there is vegetation and pasture. I understand this is due to volumetric scattering in vegetated areas and maybe differences in moisture between images?

What I am looking for is a way to make the changes in mining areas more obvious and reduce the noise from vegetation.

I am mostly using default settings, except in the coherence tool I have checked “Subtract flat-earth phase” and “Subtract topographic phase”

Below is screen shot of my process

Any pointers on parameters I could play with, further processing would be greatly appreciated

You can reduce coherence estimation noise and bias by increasing the size of the estimator window. It reduces resolution of the output so it is a trade-off. You can also do some post-procesing for example with median filtering to improve visual interpretability.