Radar speed measurement is mainly based on the principle of Doppler Effect, which calculates the velocity of moving objects by measuring the frequency shift of reflected waves. The following is the detailed process of radar speed measurement:

1、 Principle of Doppler Effect

When the target approaches the radar antenna, the reflected signal frequency will be higher than the transmitter frequency; On the contrary, when the target moves away from the antenna, the reflected signal frequency will be lower than the transmitter frequency. This frequency variation is directly proportional to the speed of the target relative to the radar.

2、 Speed measurement process

Transmitting radar waves:
The radar speed probe emits radar waves (a type of high-frequency radio wave), which propagate in space.
Receive reflected waves:
When radar waves hit moving objects (such as vehicles), they will reflect back. The radar system will then receive these reflected signals.
Measure frequency shift:
The radar system utilizes the principle of Doppler effect to measure the frequency shift between the received reflected wave and the transmitted wave. This frequency shift reflects the velocity of the target object relative to the radar.
Calculation speed:
By measuring the frequency shift, the radar system can calculate the specific velocity of the target object. This speed is the relative speed with the radar as the reference point.

3、 Application and Characteristics

Real time performance: Radar speed measurement is real-time and can complete speed measurement in a very short time.
Accuracy: Radar speed measurement has high accuracy, with an error range usually between ± 1Km/h and ± 2Km/h, meeting the requirements for traffic violation investigation.
Widely used: Radar speedometers have been widely used in industries such as traffic management and police speed testing. They can be fixed on the road surface or installed on patrol vehicles to monitor the speed of moving objects.

4、 Technical Details

Radar beam characteristics: The radar beam has a large illumination area, making it easy for radar speed measurement to capture targets without the need for precise aiming. At the same time, the electromagnetic wave beam emitted by the radar has a certain aperture angle, which affects the accuracy and effective speed measurement distance of the speed measurement.
Speed measurement distance: The maximum speed measurement distance of a radar speedometer depends on the technical parameters and transmission power of the equipment. Generally speaking, the effective speed measurement range of a radar speedometer can range from several hundred meters to several thousand meters.

Equipment calibration: In order to ensure the accuracy of speed measurement, the radar speedometer needs to be calibrated regularly. This is usually accomplished through a fixed frequency tuning fork or other standard equipment.



In summary, radar speed measurement calculates the velocity of moving objects by measuring the frequency shift of reflected waves based on the Doppler effect principle. It has the characteristics of real-time, accuracy, and wide application, and plays an important role in fields such as traffic management.