Editing Microwave (section)

===Post World War II exploitation===
After World War II, microwaves were rapidly exploited commercially.<ref name="Roer" /> Due to their high frequency they had a very large information-carrying capacity ([[bandwidth (signal processing)|bandwidth]]); a single microwave beam could carry tens of thousands of phone calls. In the 1950s and 60s transcontinental [[microwave transmission|microwave relay]] networks were built in the US and Europe to exchange telephone calls between cities and distribute television programs. In the new [[television broadcasting]] industry, from the 1940s microwave dishes were used to transmit [[backhaul (broadcasting)|backhaul]] video feeds from mobile [[production truck]]s back to the studio, allowing the first [[remote broadcast|remote TV broadcasts]]. The first [[communications satellite]]s were launched in the 1960s, which relayed telephone calls and television between widely separated points on Earth using microwave beams. In 1964, [[Arno Penzias]] and [[Robert Woodrow Wilson]] while investigating noise in a satellite horn antenna at [[Bell Labs]], Holmdel, New Jersey discovered [[cosmic microwave background radiation]].
{{multiple image
| align = center
| direction = horizontal
| header =
| image1 = Hogg horn antennas.jpg
| caption1 = C-band [[horn antenna]]s at a telephone switching center in Seattle, belonging to AT&T's Long Lines microwave relay network built in the 1960s.
| width1 = 149
| image2 = NIKE AJAX Anti-Aircraft Missile Radar3.jpg
| caption2 = Microwave lens antenna used in the radar for the 1954 [[Nike Ajax]] anti-aircraft missile
| width2 = 270
| image3 = NS Savannah microwave oven MD8.jpg
| caption3 = The first commercial microwave oven, Amana's [[Microwave ovens|Radarange]], installed in the kitchen of US merchant ship {{ship|NS|Savannah}} in 1961
| width3 = 119
| image4 = Telstar 1 replica.jpg
| caption4 = [[Telstar 1]] [[communications satellite]] launched July 10, 1962 the first satellite to relay television signals. The ring of [[microwave cavity]] antennas received the 6.39&nbsp;GHz [[uplink]], and transmitted the 4.17&nbsp;GHz [[downlink]] signal.
| width4 = 181
}}
Microwave radar became the central technology used in [[air traffic control]], maritime [[navigation]], [[anti-aircraft defense]], [[ballistic missile]] detection, and later many other uses.  Radar and satellite communication motivated the development of modern microwave antennas; the [[parabolic antenna]] (the most common type), [[cassegrain antenna]], [[lens antenna]], [[slot antenna]], and [[phased array]].

The ability of [[short wave]]s to quickly heat materials and cook food had been investigated in the 1930s by Ilia E. Mouromtseff at Westinghouse, and at the [[1933 Chicago World's Fair]] demonstrated cooking meals with a 60&nbsp;MHz radio transmitter.<ref name="SWC">{{cite journal| title = Cooking with Short Waves| journal = Short Wave Craft| volume = 4| issue = 7| page = 394| date = November 1933| url = http://www.americanradiohistory.com/Archive-Short-Wave-Television/30s/SW-TV-1933-11.pdf| access-date = 23 March 2015}}</ref> In 1945 [[Percy Spencer]], an engineer working on radar at [[Raytheon]], noticed that microwave radiation from a magnetron oscillator melted a candy bar in his pocket. He investigated cooking with microwaves and invented the [[microwave oven]], consisting of a magnetron feeding microwaves into a closed metal cavity containing food, which was patented by Raytheon on 8 October 1945. Due to their expense microwave ovens were initially used in institutional kitchens, but by 1986 roughly 25% of households in the U.S. owned one.   Microwave heating became widely used as an industrial process in industries such as plastics fabrication, and as a medical therapy to kill cancer cells in [[hyperthermy|microwave hyperthermy]].

The [[traveling wave tube]] (TWT) developed in 1943 by [[Rudolph Kompfner]] and [[John R. Pierce|John Pierce]] provided a high-power tunable source of microwaves up to 50&nbsp;GHz and became the most widely used microwave tube (besides the ubiquitous magnetron used in microwave ovens). The [[gyrotron]] tube family developed in Russia could produce megawatts of power up into [[millimeter wave]] frequencies and is used in industrial heating and [[plasma (physics)|plasma]] research, and to power [[particle accelerator]]s and nuclear [[fusion reactor]]s.