Milstar program


Series of military communications satellites built by Lockheed and also known as ES-8A. The operational constellation consisted of three satellites in a near geostationary orbit. They were equipped with transponders operating in the 45/21 GHz, to service mobile military terminals, 225/400 MHz and 60 GHz bands, the latter for satellite to satellite communications.

The Milstar team is led by the MILSATCOM Joint Program Office at the Air Force Space and Missile Systems Center in El Segundo, CA. TRW Space and Electronics Group provides the low data rate payload for the satellite. Hughes Aircraft Company is providing the medium data rate payload for Milstar Block 2. The major technologies aboard are on-board signal processing and routing and inter-satellite links.

US military communication system. To provide secure worldwide wartime telecommunications. The satellites apply the switchboard in space concept and provide on-board signal processing, signal routing, resource control, crossbanding and satellite crosslinks.

Milstar-1 was also known as Development Flight Satellite (DFS)-1 and, in addition to the normal payload, may have carried a technology experiment as part of the Brilliant Pebbles programme. With the introduction of Milstar 2-1 the capacity was increased to 32 transponders in the 45/21 GHz band whilst the Medium Data Rate payload and a crosslink capacity at 60 GHz were introduced on Milstar 2-2 and Milstar 2-3 respectively.

The GAO reported the first 2 Milstar have serious problems which hinder there capability to carry out their missions. The report notes that there us a chance that the system (even with the second series of Milstar) could degrade below a minimally acceptable level in 2003.

The followup program (advanced EHF, AEHF, also called Milstar 3) has Lockheed Martin as prime contractor but will contract parts with TRW (digital processing subsystems) and Hughes (payload integration). The system will consist of 4 satellites (with in-orbit links) covering from 65° north to 65° south. Transmission rates should be 10 times those of Milstar 2 (fastest channel: 8.2 Mbps). Approx 500 Mbps throughput per satellite. First satellite planned in late 2004. The program is to cost approx $3 billion.

Launch list:

Name Intl. Designation Launch Re-entry Notes
Milstar 1-1 1994 009A 7-Feb-1994   Also known as USA-99 and DFS-1
Milstar 1-2 1995 060A 6-Nov-1995   Also known as USA-115
Milstar 2-1 1999 023A 30-Apr-1999   Also known as USA-143; failed to achieve correct orbit
Milstar 2-2 2001 009A 27-Feb-2001   Also known as USA-157
Milstar 2-3 2002 001A 16-Jan-2002   Also known as USA-164
Milstar 2-4 2003 012A 8-Apr-2003   Also known as USA-169

External resources

Ref: #15, #98a, #99 - update: 30.06.05