The National Reconnaissance Office (NRO) is a member of the United States Intelligence Community and an agency of the United States Department of Defense which designs, builds, launches, and operates the reconnaissance satellites of the U.S. federal government. It provides satellite intelligence to several government agencies, particularly signals intelligence (SIGINT) to the National Security Agency (NSA), imagery intelligence (IMINT) to the National Geospatial-Intelligence Agency (NGA), and measurement and signature intelligence (MASINT) to the Defense Intelligence Agency (DIA). The NRO announced in 2023 that it plans within the following decade to quadruple the number of satellites it operates and increase the number of signals and images it delivers by a factor of ten.
The Central Security Service (CSS) is a combat support agency of the United States Department of Defense which was established in 1972 to integrate the National Security Agency (NSA) and the Service Cryptologic Components (SCC) of the United States Armed Forces in the field of signals intelligence, cryptology, and information assurance at the tactical level. In 2002, the CSS had approximately 25,000 uniformed members. It is part of the United States Intelligence Community.
The SAMOS or SAMOS-E program was a relatively short-lived series of reconnaissance satellites for the United States in the early 1960s, also used as a cover for the initial development of the KH-7 GAMBIT system. Reconnaissance was performed with film cameras and television surveillance from polar low Earth orbits with film canister returns and transmittals over the United States. SAMOS was first launched in 1960 from Vandenberg Air Force Base.
Microwave transmission is the transmission of information by electromagnetic waves with wavelengths in the microwave frequency range of 300 MHz to 300 GHz of the electromagnetic spectrum. Microwave signals are normally limited to the line of sight, so long-distance transmission using these signals requires a series of repeaters forming a microwave relay network. It is possible to use microwave signals in over-the-horizon communications using tropospheric scatter, but such systems are expensive and generally used only in specialist roles.
Magnum was a class of SIGINT spy satellites reportedly operated by the National Reconnaissance Office (NRO) for the United States Central Intelligence Agency (CIA). The program remains classified, and the information that exists is speculative.
Jumpseat, also known as AFP-711 is reportedly a code name for a class of SIGINT reconnaissance satellites operated by the National Reconnaissance Office for the United States Air Force in the 1970s and 1980s. The program is classified, and much of the information in the open is speculative.
The Atlas-Agena was an American expendable launch system derived from the SM-65 Atlas missile. It was a member of the Atlas family of rockets, and was launched 109 times between 1960 and 1978. It was used to launch the first five Mariner uncrewed probes to the planets Venus and Mars, and the Ranger and Lunar Orbiter uncrewed probes to the Moon. The upper stage was also used as an uncrewed orbital target vehicle for the Gemini crewed spacecraft to practice rendezvous and docking. However, the launch vehicle family was originally developed for the Air Force and most of its launches were classified DoD payloads.
Canyon was a series of seven United States spy satellites launched between 1968 and 1977. Also known by its program number AFP-827, the satellites were developed with the participation of the Air Force. The Canyon project is credited as being the first American satellite system tasked for COMINT.
Orion, also known as Mentor or Advanced Orion, is a class of United States spy satellites that collect signals intelligence (SIGINT) from space. Operated by the National Reconnaissance Office (NRO) and developed with input from the Central Intelligence Agency (CIA), eight have been launched from Cape Canaveral on Titan IV and Delta IV launch vehicles since 1995.
Advanced Extremely High Frequency (AEHF) is a constellation of communications satellites operated by the United States Space Force. They are used to relay secure communications for the United States Armed Forces, the British Armed Forces, the Canadian Armed Forces, the Netherlands Armed Forces and the Australian Defence Force. The system consists of six satellites in geostationary orbits. The final satellite was launched on 26 March 2020. AEHF is backward compatible with, and replaces, the older Milstar system and will operate at 44 GHz uplink and 20 GHz downlink. The AEHF system is a joint service communications system that provides survivable, global, secure, protected, and jam-resistant communications for high-priority military ground, sea and air assets.
Signals intelligence by alliances, nations and industries comprises signals intelligence (SIGINT) gathering activities by national and non-national entities; these entities are commonly responsible for communications security (COMSEC) as well.
Signals intelligence operational platforms are employed by nations to collect signals intelligence, which is intelligence-gathering by interception of signals, whether between people or between machines, or mixtures of the two. As sensitive information is often encrypted, signals intelligence often involves the use of cryptanalysis. However, traffic analysis—the study of who is signalling whom and in what quantity—can often produce valuable information, even when the messages themselves cannot be decrypted.
Marisat satellites were the first mobile telecommunications satellites and were designed to provide dependable telecommunications for commercial shipping and the U.S. Navy from stable geosynchronous orbital locations over the three major ocean regions. The three Marisat satellites, F1, F2, and F3, were built by Hughes Aircraft Corporation (HAC) for COMSAT Corporation starting in 1973. The satellites were designed to provide maritime telecommunications services in three large ocean areas, the Atlantic Ocean, the Pacific Ocean, and the Indian Ocean, and were located at 72.5° East longitude, 176.5° E, and 345° E in the geosynchronous orbital arc. The three-satellite Marisat system served as the initial INMARSAT constellation.
After the end of World War II, all the Western allies began a rapid drawdown of military forces, including those of signals intelligence. At the time, the US still had a COMINT organization split between the Army and Navy. A 1946 plan listed Russia, China, and a [redacted] country as high-priority targets.
The Atlas SLV-3, or SLV-3 Atlas was an American expendable launch system derived from the SM-65 Atlas / SM-65D Atlas missile. It was a member of the Atlas family of rockets.
Discoverer 20, also known as KH-5 9014A, was a USAF photographic reconnaissance satellite under the supervision of the National Reconnaissance Office (NRO) which was launched in 1961. Discoverer 20 was the first KH-5 ARGON satellite to be launched.
Vortex, previously known as Chalet, was a class of spy satellite operated by the United States during the 1980s and 1990s to collect signals intelligence (SIGINT) from high Earth orbit. The Vortex satellites were operated by the National Reconnaissance Office for the United States Air Force and listened to radio transmissions originating from Earth or space. The intercepted data is believed to have been fed into and analyzed by the National Security Agency ECHELON system.
Telstar is the name of various communications satellites. The first two Telstar satellites were experimental and nearly identical. Telstar 1 launched on top of a Thor-Delta rocket on July 10, 1962. It successfully relayed through space the first television pictures, telephone calls, and telegraph images, and provided the first live transatlantic television feed. Telstar 2 was launched May 7, 1963. Telstar 1 and 2—though no longer functional—still orbit the Earth.
A SIGINT Activity Designator identifies a signals intelligence (SIGINT) line of collection activity associated with a signals collection station, such as a base or a ship. For example, the SIGAD for Menwith Hill in the UK is USD1000. SIGADs are used by the signals intelligence agencies of the United States, the United Kingdom, Canada, Australia and New Zealand.
The Initial Defense Communications Satellite Program or IDCSP was the first United States Department of Defense communications satellite constellation and the first stage of the Defense Communications Satellite Program (DCSP). Launched in five groups by Titan IIIC launch vehicles to near equatorial, subsynchronous orbits between 1966 and 1968, they were intended to be experimental testbeds. They were so successful that, by the time of the launch of the last set of eight satellites, the IDCSP was deemed operational and renamed Initial Defense Satellite Communications System or IDSCS. This system allowed real-time collection of battlefield intelligence during the Vietnam War. A total of 35 IDCSP satellites were launched, 27 successfully.
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