Engineering

Radar beams for networking and localizing everyday objects

In the OmniConnect project, Fraunhofer researchers are working with other partners on networking objects in indoor areas. They are doing this using radar beams and passive tags that are attached to moving objects, but also ...

Hi Tech & Innovation

Combining news media and AI to rapidly identify flooded buildings

Artificial intelligence (AI) has sped up the process of detecting flooded buildings immediately after a large-scale flood, allowing emergency personnel to direct their efforts efficiently. Now, a research group from Tohoku ...

Automotive

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 ...

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Radar

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