Archives for July 2013

How Radar Guns Used By Police Operate.

How do those devices that measure your car speed operate exactly? For over five decades police officers have been pulling over speeding drivers and handing them a ticket (or letting them off with a warning) for going over the marked speed limit.

 photo radargun_zps3c99842a.jpg

Most typically police officers will be stationary hidden away with their police speed gun either mounted in their police vehicle. Until very recently, the radars used by law enforcement were able to detect the speed of a moving car with the Doppler effect. This method measures the change in frequency, or oscillations per unit of time.

Each part of the signal is reflected when it reaches the car, mirroring the original signal exactly. But when the car is moving, each part of the radio signal made by the radar gun is reflected at a different point in space, which changes the wave pattern. When the car is moving away from the radar gun, the second segment of the signal has to travel a greater distance to reach the car than the first segment of the signal.

While conventional radar guns are still in use across the country, many police departments are increasing the radar guns sales of LIDAR radar guns. These guns detect speed by using concentrated light and lasers. A burst of infrared light is made by the LIDAR gun and clocks the time taken to return back to the starting point. It determines how far away an object is by multiplying this time by the speed of light.

Guest post is provided by Radar Guns Sales, a trusted supplier of police radar guns. Visit the website for more details.