can police track speed while moving
The radar beam. hits oncoming cars, and is reï¬ected back. to the radar unit, which can calculate. speeds from those reï¬ections. Radar can be used from a police car. thatâs either stationary or moving, since. it does not require precise aiming to. clock traï¬c speeds. There are also hand-. held units that can be operated from a. car, motorcycle, or an oï¬cer standing at. the side of the road.