The EVOLIS Radar Speed Sign is equipped with a Doppler antenna that emits magnetic waves at a certain frequency. These waves bounce off the oncoming vehicle and are sent back to the antenna at a slightly different rate than when they were generated. This difference enables the EVOLIS radar to accurately calculate the vehicle’s speed, which is then relayed to its LED display. The speed is measured in real time and the display is updated every 1.2 seconds to maintain transparency and accuracy.