Artist’s rendering of WGS-11+

Fact Sheets

Milstar Satellite Communications System



Milstar provides the President, Secretary of Defense and the U.S. armed forces with assured, survivable satellite communications (SATCOM) with low probability of interception and detection, and is designed to operate through contested environments. Milstar is operated by Space Delta 8, located at Schriever Air Force Base, Colo.


The objective of the Milstar program was to create a global, secure, nuclear-survivable, space-based communication system (considered a top national priority during the Reagan Administration in the 1980s). Milstar was designed to perform all communication processing and network routing onboard, thus eliminating the need for vulnerable land-based relay stations and reducing the chances of communications being intercepted on the ground.


The first two satellites carry a low data rate (LDR) payload. The LDR payload can transmit data over 192 channels in the range. Satellite-to-satellite crosslinks provide communications, data exchange and global coverage. The other satellites carry both LDR and medium data rate (MDR) payloads. The payloads increased data over 32 channels. The higher data rates provide the user the ability to transmit large amounts of data in a short period of time. The Milstar satellites provide continuous 24-hour coverage to the warfighter. The follow-on to Milstar, Advanced EHF (AEHF) program augments Milstar.

A key feature of the Milstar system is the use of interoperable terminals by the warfighters of the U.S. Armed Forces. For example, sea-based terminals can be used to upload data in real time onto cruise missiles carried aboard submarines and guided missile destroyers. Land-based terminals provide communications and data exchange for the mobile, ground-based warfighter. Primary command and control of the Milstar constellation is accomplished through a highly survivable mission control segment with both fixed and mobile constellation control stations. Another method of command and control uses the Air Force Satellite Control Network (AFSCN).

General Characteristics

Primary function: Survivable and protected communications
Payload: LDR, MDR, and UHF
Antennas: Crosslink: Earth Coverage (Uplinks & Downlinks), Agile Beams, Spot Beams


Feb. 7, 1994
Nov. 7, 1995
Feb. 27, 2001
Jan. 15, 2002
Apr. 8, 2003

(Current as of Oct 2020)