ALTAIR ( ARPA Long-Range Tracking And Instrumentation Radar) is a radar tracking station on

Roi-Namur Roi-Namur ( ) is an island in the north part of the Kwajalein Atoll in the Marshall Islands. Today, the island is a major part of the Ronald Reagan Ballistic Missile Defense Test Site, hosting several radar systems used for tracking and character ...

island in the north part of the Kwajalein atoll in the Marshall Islands. It is a high-sensitivity, wide-bandwidth, coherent, instrumentation and tracking radar that is capable of collecting precise measurements on small targets at long-ranges. ALTAIR supports several operating modes, including tracking and signature collection at VHF and

UHF Ultra high frequency (UHF) is the ITU designation for radio frequencies in the range between 300 megahertz (MHz) and 3 gigahertz (GHz), also known as the decimetre band as the wavelengths range from one meter to one tenth of a meter ...

. It is part of a network of contributing radar sensors that perform deep-space tracking.Card Index of Radar Sets
in Radartutorial The antenna uses a steerable 150-ft dish (46-m-diameter) and employs a focal point VHF feed and multimode Cassegrain UHF feed in conjunction with a frequency selective sub-reflector (5.5 m diameter). The radar became operational in 1969. The original task was to detect and track intercontinental ballistic missiles. It is currently used to measure satellite orbits and meteor echoes in low-Earth orbit, and to observe ionospheric irregularities and background densities.D.M.Towle: "VHF and UHF radar observations of equatorial F region ionospheric irregularities and background densities", Lincoln Laboratory, Massachusetts Institute of Technology, Lexington, Massachusetts 02173, in Radio Science 1980, p. 71

References

{{CC-notice, cc=bysa3, url=https://www.radartutorial.eu/19.kartei/01.oth/karte005.en.html Military radars of the United States