The Mount Fuji Radar System is a historic

weather radar Weather radar, also called weather surveillance radar (WSR) and Doppler weather radar, is a type of radar used to locate precipitation, calculate its motion, and estimate its type (rain, snow, hail etc.). Modern weather radars are mostly pulse- ...

system located on the summit of Mount Fuji, Japan. It was completed on August 15, 1964, and is now recorded on the

list of IEEE Milestones The following timeline tables list the discoveries and inventions in the history of electrical and electronic engineering. History of discoveries timeline History of associated inventions timeline List of IEEE Milestones The following l ...

in electrical engineering. When first built, the Mount Fuji Radar System was the world's highest weather radar (elevation 3776 meters), and could observe major weather phenomena, such as destructive

typhoon A typhoon is a mature tropical cyclone that develops between 180° and 100°E in the Northern Hemisphere. This region is referred to as the Northwestern Pacific Basin, and is the most active tropical cyclone basin on Earth, accounting for a ...

s, at a range of more than 800 kilometers. It was designed by the

Japan Meteorological Agency The , abbreviated JMA, is an agency of the Ministry of Land, Infrastructure, Transport and Tourism. It is charged with gathering and providing results for the public in Japan that are obtained from data based on daily scientific observation an ...

and built by

Mitsubishi Electric Corporation , established on 15 January 1921, is a Japanese multinational electronics and electrical equipment manufacturing company headquartered in Tokyo, Japan. It is one of the core companies of Mitsubishi. The products from MELCO include elevators an ...

. The system is notable for its advances in weather radar technology,

remote control In electronics, a remote control (also known as a remote or clicker) is an electronic device used to operate another device from a distance, usually wirelessly. In consumer electronics, a remote control can be used to operate devices such a ...

, and difficulty of construction, as it required the transport and assembly of some 500 tons of material during mountain's short summer. It operated at a frequency of 2880 megahertz, with output power of 1500 kilowatts, and a pulse width of 3.5

microsecond A microsecond is a unit of time in the International System of Units (SI) equal to one millionth (0.000001 or 10−6 or ) of a second. Its symbol is μs, sometimes simplified to us when Unicode is not available. A microsecond is equal to 1000 ...

s. Its antenna was a circular dish, 5 meters in diameter, of parabolic shape, rotating at either 3 or 5 revolutions per minute, and housed within a 9-meter

radome A radome (a portmanteau of radar and dome) is a structural, weatherproof enclosure that protects a radar antenna. The radome is constructed of material transparent to radio waves. Radomes protect the antenna from weather and conceal antenna e ...

. The system was decommissioned in 1999, as it was superseded by

weather satellite A weather satellite or meteorological satellite is a type of Earth observation satellite that is primarily used to monitor the weather and climate of the Earth. Satellites can be polar orbiting (covering the entire Earth asynchronously), or ...

s. The dome, radar dish and support equipment were relocated to a purpose-built museum in

Fujiyoshida is a city located in Yamanashi Prefecture, Japan. , the city had an estimated population of 48,782 in 19,806 households and a population density of 400 persons per km2. The total area of the city is . Geography Fujiyoshida lies at the northern ...

, Yamanashi in 2001. It was replaced by an automated weather system in 2004.

References

Mt. Fuji weather radar station on the IEEE Global Milestones Portal
* Tapan K. Sarkar, Robert Mailloux, Arthur A. Oliner, Magdalena Salazar-Palma, Dipak L. Sengupta, ''History of Wireless'', Wiley-IEEE, 2006, pages 470-471. .

;Specific Weather radars Mount Fuji Japan Meteorological Agency {{meteorology-stub