What does low frequency Doppler represent in moving RADAR?

In the context of moving RADAR, low frequency Doppler specifically represents the speed of the patrol vehicle itself. This is because the low frequency shift detected by the RADAR is primarily influenced by the speed of the unit that the radar system is deployed in, which is typically the patrol vehicle.

When a moving radar system is in operation, it continuously emits radar waves and measures the frequency of the waves returning after they bounce off of targets, such as other vehicles. The frequency shift relates to the relative motion between the radar unit and the target. In the case of the patrol vehicle, the low frequency Doppler indicates how fast the patrol unit is traveling.

This is essential for the proper functioning of the RADAR system because it enables the operator to differentiate between the speed of the patrol vehicle and the speeds of other vehicles. Therefore, understanding that low frequency Doppler correlates to the patrol speed is critical for accurate speed enforcement and operator training.