Mad idea

Although they are doing it for an entirely different reason someone has developed a device for scanning Antarctic ice surfaces for shallow buried iron meteorites which otherwise bury themselves in sunlight.

Well sure, very few parts, but most likely any real world solution to a RADAR problem will many transistors, most likely millions.

Rick C.

You could have said this in your original post...

Rick C.

For the DSP/FPGA alone. Why not? They're free.

I'm not the OP. I replied to Bill Beaty, who also was not the OP. He mentioned "local altitude sensing" and I replied. In that context it was obvious we weren't talking about the metal detection function.

Yes and it didn't trigger on just proximity but on the doppler effect too, it had to be "looming proximity" not static proximity!

piglet