Ground-to-Air Transmitter Facilities (GAT Facility) were surface-to-air missile radio uplink stations of 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 Signal ...

. They were located near

CIM-10 Bomarc The Boeing CIM-10 BOMARC (Boeing Michigan Aeronautical Research Center) (IM-99 Weapon System prior to September 1962) was a supersonic ramjet powered long-range surface-to-air missile (SAM) used during the Cold War for the air defense of North ...

bases (e.g., Suffolk County Missile Annex on

Long Island Long Island is a densely populated island in the southeastern region of the U.S. state of New York (state), New York, part of the New York metropolitan area. With over 8 million people, Long Island is the most populous island in the United Sta ...

) for

command guidance Command guidance is a type of missile guidance in which a ground station or aircraft relay signals to a guided missile via radio control or through a wire connecting the missile to the launcher and tell the missile where to steer to intercept its ...

of the Interceptor Missiles.Distances of each GAT Facility from the Launch Area were

tbd To be announced (TBA), to be confirmed (TBC), to be determined or decided or declared (TBD), and other variations, are placeholder terms used very broadly in event planning to indicate that although something is scheduled or expected to happen, a ...

(Patrick),

(Hurlburt)(http://www.radomes.org/museum/HurlburtFieldBOMARCFLGATSite.html/documents ) 1 mile (

McGuire The MacGuire ( ) family is an Irish clan based in County Fermanagh. The name derives from the Gaelic , which is "son of Odhar" meaning "dun", "dark one". According to legend, this relates to the eleventh descendant of Colla da Chrich, great-gran ...

), 2⅓ mi (Suffolk), 2¼ mi (Otis), 4½ mi (Dow), 4½ mi (Langley),

(Sault Ste. Marie),

(Ottawa). The unmanned sites with a transmitter building and 2 antenna towers converted the digital "midcourse guidance commands" (after the launch/climb and before the homing dive) received from an

AN/FSQ-7 Combat Direction Central The AN/FSQ-7 Combat Direction Central, referred to as the Q7 for short, was a computerized command and control system for Cold War ground-controlled interception used in the USAF Semi-Automatic Ground Environment (SAGE) air defense network. The ...

into the transmitter building's Digital Data Receivers, processing 28 channels of uplink data. Processing by the AN/GKA-4A's demultiplexer group prepared the SAGE data for

amplitude modulation Amplitude modulation (AM) is a modulation technique used in electronic communication, most commonly for transmitting messages with a radio wave. In amplitude modulation, the amplitude (signal strength) of the wave is varied in proportion to ...

on separate frequencies for each missile (FDDL: frequency-division data link), e.g., 3 missiles were simultaneously controlled in a 1960 test. An AN/GRT-3 transmitter provided the modulated signals to a UHF Klystron high power amplifier—dual chains of components provided redundancy, including 2 exterior GAT Antennas on GAT Towers from which a missile's "command receiver" demodulated the signal. A single local monitoring cabinet allowed review of either chain's function (e.g., during test input to the dummy load), ventilation provided cooling of the building equipment, and "three 150 KVA diesel driven generators housed in the GAT building" provided power. For the advanced Bomarc (IM-99B), a Time-Division Data Link was planned for GAT Facilities to provide an

electronic counter-countermeasures Electronic counter-countermeasures (ECCM) is a part of electronic warfare which includes a variety of practices which attempt to reduce or eliminate the effect of electronic countermeasures (ECM) on electronic sensors aboard vehicles, ships and ai ...

capability using a "directional hlgh-gain data link antenna…composed of 16 stationary segments in a circular pattern 60 feet high".

References

* {{Cite report , date=December 3, 1959 , title=IM-99A Bases Manual , location=Seattle, Washington , publisher=Boeing: Pilotless Aircraft Division , quote=Differences in the Langley Base layout are due to planning for accommodation of the advanced missile system M-99Bground equipment with reviousequipment for the IM-99A system

External links

Remaining Langley GAT building and tower
Aerial warfare ground equipment Equipment of the United States Air Force Anti-aircraft warfare Defunct radio stations in the United States