Category
page 1Defunct satellite navigation systems
Transit
satellite navigation system
Tsikada
Tsikada ( meaning cicada) was a Soviet satellite navigation system including ten Low Earth Orbit (LEO) satellites. It transmitted the same two carrier frequencies as the U.S. TRANSIT satellite system. The first satellite was launched in 1974.
Tsiklon
satellite constellation
Timation
thumb|The Naval Research Laboratory’s managers for the Timation program and, later, the GPS program: [[Roger L. Easton (left) and Al Bartholomew.]]
thumb|Timation 1 (rectangular object in center of photo), launched May 31, 1967, tested in a "piggyback" launch aboard an Air Force Thor-Agena D rocket
The Timation satellites were conceived, developed, and launched by the United States Naval Research Laboratory in Washington, D.C. beginning in 1964. The concept of Timation was to broadcast an accurate time reference for use as a ranging signal to receivers on the ground.