The AN/FPS-6 Radar was a long-range
height finding radar
A height finder is a ground-based aircraft altitude measuring device. Early height finders were optical range finder devices combined with simple mechanical computers, while later systems migrated to radar devices. The unique vertical oscillating ...
used by the
United States Air Force
The United States Air Force (USAF) is the air service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part of the United States Army Si ...
's
Air Defense Command
Aerospace Defense Command was a major command of the United States Air Force, responsible for continental air defense. It was activated in 1968 and disbanded in 1980. Its predecessor, Air Defense Command, was established in 1946, briefly inac ...
. The AN/FPS-6 radar was introduced into service in the late 1950s and served as the principal height-finder radar for the United States for several decades thereafter. It was also used by the
Royal Air Force
The Royal Air Force (RAF) is the United Kingdom's air and space force. It was formed towards the end of the First World War on 1 April 1918, becoming the first independent air force in the world, by regrouping the Royal Flying Corps (RFC) an ...
alongside their
AMES Type 80
The AMES Type 80, sometimes known by its development rainbow code Green Garlic, was a powerful early warning (EW) and ground-controlled interception (GCI) radar developed by the Telecommunications Research Establishment (TRE) and built by Decca ...
s. Built by General Electric, the S-band radar operated on a frequency of 2700 to 2900 MHz. Between 1953 and 1960, about 450 units of the AN/FPS-6 and the mobile AN/MPS-14 version were produced. The AN/FPS-90 and AN/FPS-116 radars were identical to the AN/FPS-6 except for receiver modifications.
Operation
The radar consisted of an antenna group, a transmitter group, a receiver group, and an ancillary group. Most fixed sites had a remote group, which allowed the control of the radar from inside the operations center. Also located in operations, was the anti-jam receivers. These receivers were
fed with raw video from the tower receiver, and output several types of processed video to enable operators to see through jamming.
The ancillary group originally consisted of an AN/OA-270 Range Height Indicator (RHI), and then later upgraded to an AN/OA-929 RHI, which displayed the raw or anti-jam video, and allowed the operator to position the azimuth of the antenna. At SAGE sites, the antenna azimuth was selected by command from the Air Division, and the operator could slew the antenna plus or minus ten degrees for fine adjustment.
The AN/FPS-90 radar was designated a high-power model, using a QK-338A magnetron and rated at 4.5 MW peak power, versus the QK-327A magnetron at 3.5 MW peak power. The receiver mixer was also modified to handle the larger signal dynamic range. Due to maintenance costs and high failure rates, these radars were all retrofitted to the same magnetron as the AN/FPS-6 by the late 1960s, and were no longer high power. The radar maintained its AN/FPS-90 designation due to the receiver modifications. Everything else was identical.
See also
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Joint Electronics Type Designation System
The Joint Electronics Type Designation System (JETDS), which was previously known as the Joint Army-Navy Nomenclature System (AN System. JAN) and the Joint Communications-Electronics Nomenclature System, is a method developed by the U.S. War Depa ...
*
List of military electronics of the United States
This article lists types of American military electronic instruments along with brief descriptions of them. Electronic items of this sort are assigned designations according to the Joint Electronics Type Designation System, beginning with the AN ...
External links
Ground radars
Radars of the United States Air Force
General Electric radars
Height-finding radars
Military equipment introduced in the 1950s
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