constellation will link command authorities with a wide variety of resources,
including ships, submarines, aircraft and ground stations.
will be the most advanced military communications satellite system to date and
represents the future of the U.S. communications capability. The operational Milstar
satellite constellation will be composed of four satellites positioned around
the Earth in geosynchronous orbits plus a polar adjunct system. Each mid-latitude
satellite will weigh approximately 10,000 pounds and have a design life of 10
years. The first Milstar satellite was launched Feb. 7, 1994 aboard a Titan IV
expendable launch vehicle. The second low data rate satellite is scheduled for
launch in 1995. Beginning with the third launch in 1998, the satellites will have
greatly increased capacity because of an additional medium data rate payload.
A total of six launches are currently planned.
satellite serves as a smart switchboard in space by directing traffic from terminal
to terminal anywhere on the Earth. Since the satellite actually processes the
communications signal and can link with other satellites through crosslinks, the
requirement for ground controlled switching is significantly reduced. The satellite
establishes, maintains, reconfigures and disassembles required communications
circuits as directed by the users. Milstar terminals will provide encrypted voice,
data, teletype, or facsimile communications. A key goal of Milstar is to provide
interoperable communications among the users of Army, Navy, and Air Force Milstar
terminals. Geographically dispersed mobile and fixed control stations provide
survivable and enduring operational command and control for the Milstar constellation.
Milstar system is composed of three segments: space (the satellites), terminal
(the users), and mission control. Air Force Materiel Command's Space and Missile
Systems Center (SMC) at Los Angeles Air Force Base, California, is responsible for
development and acquisition of the Milstar space and mission control segments.
Electronics Systems Center (ESC) at Hanscom Air Force Base, Mass., is responsible
for the Air Force portion of the terminal segment development and acquisition.
The 4th Space Operations Squadron at Falcon AFB, Colo., is the front line organization
providing real time satellite platform control and communications payload management.
Weight: About 10,000 pounds
altitude: 22,400 nautical miles (inclined geostationary orbit)
Solar panels generating 8,000 watts
Payload: Low data rate communications
(voice, data, teletype and facsimile) at 75 bps to 2,400 bps (All satellites)
data rate communications (voice, data, teletype, facsimile) at 4.8 Kbps to 1.544
Mbps (Satellites 3 through 6 only)
Launch vehicle: Titan IV/Centaur upper
Primary contractor: Lockheed
(Current as of July 1995)