Here’s how cops bust you for speeding: First ever in-depth look of a police interceptor

Overspeeding is one of the prime reasons for accidents in India. The authorities and the law enforcers do try to keep the speeding vehicles in check by implementing speed detecting cameras on the roads and highways. There are fixed type speed detecting cameras that are permanently installed on the poles. Police also surprise the road users by using Interceptor vehicles that have such speed detection cameras installed. These are mobile and can be positioned anywhere along the roads.

Here is a live video that shows how speed detecting cameras work. The video by Keshav Today shows how the cops use the set-up. The video is from Haryana. The cops here are using radar-based speed detection systems, which are more widely used around the world. However, there are also laser-based speed detection systems, which are more advanced and precise.

The speed trap camera is installed in the boot of the Maruti Suzuki Ertiga of the police team. There is an operator who targets various cars to check the speed. The camera shows the speed of the moving vehicle to inform the operator. The operator then tells the vehicle number to his colleagues who stop and issue an overspeeding challan to the violators.

Here’s how cops bust you for speeding: First ever in-depth look of a police interceptor

During the live video, two cars crossed the speed limit of 90 km/h. The cops waved them to stop and issued a challan. The cops also said that they have to pay a fine of Rs 2,000 and the license gets barred for 3 months. It is a court challan, which means that the violator will have to visit the court to submit his license and the challan amount. In India, the fine for speeding has increased over the years to discourage motorists from speeding.

How do the speed trap cameras work?

Since they used radar-based cameras, we will only talk about the technology used in this system. A radar camera uses the Doppler Effect to detect the speed of the cars. The radar can be of different forms including the handheld guns or the ones that we see here.

The radar-based camera throws radio waves that travel at the speed of light. The radio wave hits the moving vehicle and depending on the speed, the frequency of the radio wave gets compressed. When the wave travels back to the radar-based camera, it then calculates the speed in real-time. The same system can be used for cars that go away from the camera. In that case, the frequency of the radio waves become longer or longitudinal.

Laser guns also use similar technology but they are much more precise and much more expensive as well. Modern radar-based cameras also come with an ANPR or Automatic Number Plate Recognition system that also correctly identifies the registration number of the car.

In most cases, the cops remain hidden from the view of the motorists but this video shows them parked right on the highways, which can be dangerous to the motorists as well. The range of radar-based cameras is about 2 km, depending on the cameras.

Shantonil Nag

Shantonil Nag, senior feature writer at, channels his expertise and enthusiasm into insightful car reviews and test drives. (Full bio)