Re: Great
RADAR specifically, in cars, would create 'RF pollution' if EVERYBODY does it. All of those RADAR systems interfering with one another... and there are other logistic problems with RADAR, like a 'blind spot' directly in front of the antenna, for when the 'pulse going out' switch hasn't turned off yet on the wave guide [to protect front-end components, you have to temporarily short out the input circuit while transmitting the high power pulse]. Additionaly, high power microwaves for long periods of time are bad for fleshies. You use these when cooking in a microwave oven, right?
But the worst of it is the object resolution. To properly resolve an object or distance that's 10 cm you will more than likely need a "much less than 10cm" wavelength (although phase shift detection MIGHT let you do it, if you like super-sophisticated detectors like that). 10cm is 30Ghz, and it'll only get more expensive (and require higher output power) as wavelength drops.
And you thought it was bad when running a microwave oven caused your bluetooth and/or wifi devices to temporarily disconnect... imagine a bozillian cars doing the SAME! THING!
well it's been decades since I did anything with a RADAR system and so the tech has probably improved, but the general principles remain the same
A 'FLIR' system (plus optical) might be the best choice (assuming it's already part of the package), especially for detecting cars and people. They tend to emit infrared light on their own, too.