Synthetic Aperture Radar Autofocus and Calibration
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Synthetic Aperture Radar
Radar Technology
Diy Projects
Signal Processing
The post showcases a DIY Synthetic Aperture Radar (SAR) project with impressive results, sparking discussion on the technical achievements and the conditions that enable such deep tinkering and innovation.
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Homemade polarimetric synthetic aperture radar drone - https://news.ycombinator.com/item?id=43073808 - Feb 2025 (60 comments)
His work is pretty amazing actually. Lots of little details he’s worked out and built upon. Someday I’d like to replicate his designs.
The EHT black hole telescope is an example of VLBI.
And there’s a similar field of synthetic aperture ultrasound which is where I did a ton of work a decade ago.
https://en.wikipedia.org/wiki/John_Harrison
https://en.wikipedia.org/wiki/Isaac_Newton
And I'm sure lots more?
Or maybe more generally Europe circa 18th century?
Probably a lot more creativity/discovery/"personal projects" vs. the US 50s or 60's would be my guess? So we need prosperity and a monarchy?
What places have this today? I see an answer suggesting AUS below. ChatGPT says Switzerland
https://hforsten.com/homemade-synthetic-aperture-radar.html
https://hackaday.com/2019/08/15/bike-mounted-synthetic-apert...
This hobbyist SAR project made by hforsten absolutely nuts. Wonderful.
He mastered mechanics, electronics, software and applied higher math of the highest difficulty grade. Guess we have to call this "The Holy Quadrivium".
Back to the tech:
Radar stuff is very interesting. Reverse Engineering cheap FMCW radars from China makes these very accessable to hobbyists too. Often you "only" have to care about the VCO for the frequency sweep and then read back the I/Q channels using two sync'ed ADCs. Then you can play around with algorithms to analyze the signals.
These 24GHz Car Speed CW (you see next to streets) radars can be used for classifying rain drops for example. They antenna pattern is quite sharp and they have high gain.
We need more articles uncovering the SAR mechanics, even for Satellite Data.