Browse Resources by Country
Europe launched the first test satellite in the Galileo system in December 2005.
Read MoreThe U.S. NAVSTAR (Navigation Signal Timing and Ranging) GPS constellation consists of ## active and ## spare satellites in MEO. According to the DoD, the fundamental concept of GPS is to use simultaneous distance measurements from ## satellites to compute the position and time of any receiver. The GPS signal is available without cost to users around the world and has spawned many commercial applications.
Read MoreGround station infrastructure provides command, control, tracking, and telemetry systems for launch vehicles, satellites, and other platforms. Worldwide tracking systems operated by government agencies support launch command and control. Satellite ground stations are operated either by commercial or government entities; their components include the large satellite receivers used to transmit and receive signals to and from satellites on orbit for the purpose of communication, navigation, or data transfer.
Read More