Homemade polarimetric synthetic aperture radar drone

This is dang cool. Admittedly I skimmed the post due to the technical nature of radar I don't understand, but I gather the radar imaging near the bottom was not real-time? I would assume processing on-device to create images wouldn't be feasible.

Is AESA possible or are the components restricted to the defense industry? While FCC didn't play into the op's post, are there any FCC concerns with SAR?

This project is incredible and the author is an exceptional talent. So much complexity spanning multiple disciplines.

The radar PCB is incredibly complex and dense, and worked on the first revision with only one minor issue. That's remarkable. Imagine writing an entire software application and the first time you build it runs as intended with only a couple compiler warnings.