with my personal experiences having 7 radars shots of my car, the minimum speed limit is 80, then 100 and 120

after the shots u can findout exactly which road , what speed u where at while visiting the traffic dept. while u pay. speed is clearly mentioned at the snaps.
Radars work on radio frequency.
Leadars ar more accurate because the signals ar digital,

but Radars are enough for qatar because of the enviornmental condition -weather