The compact in-ground AccuSense MicroRadar works using the same principle as any other radar. High frequency RF pulses are transmitted, bounced off a target object, and the return pulses are measured by a time-gated RF mixer. RF reflections are analyzed to produce presence, distance, and motion measurements.
AccuSense MicroRadar sensors are installed very close to the roadway surface and are capable of detecting trains, cars, trucks, and bicycles. AccuSense MicroRadar sensors are also capable of detecting and distinguishing objects in motion from objects that are stationary, as well as large objects from small objects. AccuSense MicroRadar sensors have a programmable detection range between 4’ (1.2 m) and 10’ (3 m). The width of a detection zone is approximately 90 degrees and the default range is 6’ (2 m). AccuSense MicroRadar sensors can detect bicycles that are stopped at a stop bar and differentiate between a vehicle and a bicycle. The basic method to differentiate bicycles from vehicles is based on measuring the breadth of the returned RF signal. Bicycles yield relatively small breadth values while vehicles generate both small and large values depending on the location of the vehicle. AccuSense MicroRadar sensors can also detect vehicles parked on the street or in a parking lot. Since there is always the possibility of a person or a vehicle moving in or near the detection zone, a filter is applied during detection to eliminate the effects of nearby moving objects. The filter removes any short term variations so that detection is performed only on that part of the return signal that is long term stationary.