Smarter traffic signs ahead?

Ever get caught up in a pileup or have a near miss with one during bad weather? Researchers in Poland have created smart road signs that use built-in Doppler radar, video, and acoustic radar and weather stations to monitor ...

Electronics & Semiconductors

Development of highly compact radar sensors for industry

Radar systems have long been used on aircraft or ships. Now, they are increasingly applied in cars for the 'short range' in particular. Thanks to the great progress achieved in semiconductor technology in the past years, ...

Hi Tech & Innovation

New automotive radar spots hazards around corners

Using radar commonly deployed to track speeders and fastballs, researchers have developed an automated system that will allow cars to peer around corners and spot oncoming traffic and pedestrians.

Electronics & Semiconductors

A terahertz wave radar based on leaky-wave coherence tomography

Researchers at Keio University and the National Institute of Information and Communications Technology (NICT) in Japan have recently introduced a new design for a terahertz wave radar based on a technique known as leaky-wave ...

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Radar is an object detection system that uses electromagnetic waves to identify the range, altitude, direction, or speed of both moving and fixed objects such as aircraft, ships, motor vehicles, weather formations, and terrain. The term RADAR was coined in 1941 as an acronym for radio detection and ranging. The term has since entered the English language as a standard word, radar, losing the capitalization. Radar was originally called RDF (Radio Direction Finder, now used as a totally different device) in the United Kingdom.

A radar system has a transmitter that emits microwaves or radio waves. These waves are in phase when emitted, and when they come into contact with an object are scattered in all directions. The signal is thus partly reflected back and it has a slight change of wavelength (and thus frequency) if the target is moving. The receiver is usually, but not always, in the same location as the transmitter. Although the signal returned is usually very weak, the signal can be amplified through use of electronic techniques in the receiver and in the antenna configuration. This enables radar to detect objects at ranges where other emissions, such as sound or visible light, would be too weak to detect. Radar is used in meteorological detection of precipitation, measuring ocean surface waves, air traffic control, police detection of speeding traffic, and by the military.

This text uses material from Wikipedia, licensed under CC BY-SA