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Radar

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Radar is a way to see things that are far away.

Radaroperation
Radaroperation

It uses radio waves to find where objects are. These waves help us learn an object's distance, which is called ranging. We can also find its direction, known as azimuth and elevation. Radar can even tell us how fast an object is moving. This tool is very important for many different jobs. It helps us track planes, ships, and even weather patterns.

weather radar
weather radar

A radar system works in a few clear steps. First, a transmitter creates electromagnetic waves. These waves are in the radio or microwave domain. A transmitting antenna sends these waves out into the world. When the waves hit an object, they bounce back.

Radaroperation
Radaroperation

This is like an echo in a large room. A receiving antenna catches these returning waves. Finally, a receiver and processor study the waves. This tells us the location and speed of the object.

Many people worked to make radar a reality. In 1886, Heinrich Hertz showed radio waves could reflect off solids. Later, Alexander Popov noticed interference from ships in 1897. In 1904, Christian Hülsmeyer built a device called a telemobiloscope. He used it to find ships in thick fog.

Watson Radar
Watson Radar

In the 1930s, Robert Watson-Watt and Arnold Wilkins did famous tests. They used a BBC transmitter to find a bomber in 1935. This work helped create the Chain Home system in the UK.

Chain home
Chain home

History shows how radar grew during big events. The U.S. Navy named it RADAR in 1940. This name stands for "radio detection and ranging." During World War II, many countries developed it secretly. In the UK, the cavity magnetron was a huge step. This invention allowed for much smaller radar systems.

Early radar antenna - US Naval Research Laboratory Anacostia
Early radar antenna - US Naval Research Laboratory Anacostia

In the Soviet Union, engineers built the RAPID system. It could find an aircraft within 3 km. The first Russian airborne radar was the Gneiss-2. It began flying on bombers in June 1943.

Today, radar is part of our everyday lives. It helps air traffic controllers keep planes safe.

SPS-10 radar antenna on a Knox class frigate
SPS-10 radar antenna on a Knox class frigate

Marine radar helps ships find landmarks and other boats.

Rotating marine radar - rotating waveguide antenna
Rotating marine radar - rotating waveguide antenna

We even use it to watch for storms. Meteorologists use it to monitor precipitation. Some new cars use radar to drive themselves.

3D Doppler Radar Spectrum showing a Barker Code of 13
3D Doppler Radar Spectrum showing a Barker Code of 13

It even helps scientists look at outer space. Radar makes the invisible world much easier to see.

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🖼️ Images & Media (19)
File:Early radar antenna - US Naval Research Laboratory Anacostia.jpg
Early radar antenna - US Naval Research...
File:Watson Radar.jpg
Watson Radar.jpg
File:Chain home.jpg
Chain home.jpg
File:Watson watt 02 fr.jpg
Watson watt 02 fr.jpg
File:East Coast Chain Home radar station CH15176.jpg
East Coast Chain Home radar station CH15176.jpg
File:Rotating marine radar - rotating waveguide antenna.gif
Rotating marine radar - rotating...
File:3D Doppler Radar Spectrum showing a Barker Code of 13.jpg
3D Doppler Radar Spectrum showing a...
File:weather radar.jpg
weather radar.jpg
File:Doppler effect diagrammatic.svg
Doppler effect diagrammatic.svg
File:Radar-hauteur-en.svg
Radar-hauteur-en.svg
File:Multipath propagation diagram en.svg
Multipath propagation diagram en.svg
File:Radaroperation.gif
Radaroperation.gif

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