Radar is short for “radio detection and ranging” and it is an instrument that transmits a series of high frequency radio waves through pulses.
It usually helps to track objects by showing a radar echo on a monitor. A computer measures the time taken for the signal to reflect off the target to calculate its distance.
The history of the radar is traced to the work of 19th century scientist Heinrich Hertz who showed that metallic objects could reflect radio waves.
However, systems using radar technology were not built till around the 20th century.
German inventor, Christian Hülsmeyer was the first to build a simple ship detection device that would help prevent accidents during times of extreme fog.
The term “Radar” was coined by the United States Navy in 1940 and a radar machine was able to both detect a target was there, as well as, give its distance.
Soon most countries started working on systems that were able to detect enemy ships and aircrafts, to help during military operations.
A radar system used during the war was able to detect and give the distance of an approaching enemy ship or plane, or indicate if the enemy was attacking.
However, radar systems are used for other purposes too. Weather departments use weather radars that are able to forecast the weather accurately.
Geologists also use radar systems to study the atmosphere such as air pollutions and wind patterns.
Even space programmes use radar systems in space probes to map out the surfaces of distant planets, such as the Magellan space probe.
Air traffic control systems also use radar to track planes that may be in the area when other planes are taking off and landing.
The speed cameras that are fixed onto highways to track if there are speeding motorists also have radar systems installed.
Did you also know that in many grocery stores, malls, and restraints, when the doors seem to “automatically” open when you stand close to it, also use radar systems? The radar senses your presence and sends a signal that triggers the doors to open.
With the increase in technology, radar is used for three very important things today; it is mainly used to track the presence of an object/person (like the grocery doors), it is also used to detect the speed of something (like on highway cameras), and thirdly, it is used to map things (like the space probes).