Hi, im wondering if it possible to build a cct that will use radar as a ranging device upto about 50m??
and give accuracy of <1cm? is this possible if so how?
You can certainly buy a laser rangefinder that has better resolution than that. Additionally, a laser rangefinder will not have any beam footprint problems, as its beam will be orders of magnitude smaller than most radars.
Sick, Inc makes a pretty nice little laser rangefinder with 1/8 mm resolution and will work out to 50 m, albeit with a retroreflector
Not much data to go on, but you could do somethings to get good resolution. You could use a chirping radar, based on a low cost DDS synthesizer, that would give back a tone proportional to distance. You could also modulate a code onto a radar signal, and time-match filter the received signal to the transmitted to determine round trip distance.