Satellite Communications Systems Wing (MCSW) division of the Space and Missile Systems Center, located at Los Angeles AFB was responsible for development and acquisition of the Milstar space and mission control segments. The Electronic Systems Center at Hanscom AFB is responsible for the US Air Force portion of the terminal segment development and acquisition. The 4th Space Operations Squadron at Schriever AFB and the 148th Space Operations Squadron at Vandenberg AFB are responsible for providing real-time satellite control and communications payload management. In August 2010 control of the Milstar system was transferred to the Advanced Extremely High Frequency program, in preparation for the launch of the first AEHF satellite, USA-214. Advanced Extremely High Frequency satellites are intended to replace Milstar. Characteristics Milstar satellites provide secure, jam resistant, worldwide communications to meet the requirements of the United States military. They were built by Lockheed Martin Missiles and Space Corporation, at a cost of US$800 million each. Each satellite has a design life of 10 years. Six were built, of which five reached their operational geosynchronous orbits, and remain in service. Launches were made using Titan IV rockets with Centaur upper stages, and all six occurred from Space Launch Complex 40 at the Cape Canaveral Air Force Station. The satellites are designed to provide communications which are hard to detect and intercept, and to be survivable in the event of nuclear warfare. The spacecraft have a mass of , and are equipped with solar panels which generate eight kilowatts of electric power to power its transponders. Both Block I and Block II satellites provide low data-rate communications at bandwidths between 75 bit/s and 2,400 bit/s, whilst the Block II spacecraft can also provide medium data-rate communications between 4.8 kbit/s and 1.544 Mbit/s. The satellites' uplinks operate in the Q band, while their downlinks operate within the K band. The uplink corresponds to the extremely high frequency band while downlink corresponds to the super high frequency radio band. Spacecraft See also Advanced Extremely High Frequency Defense Satellite Communications System Transformational Satellite Communications System Wideband Global SATCOM system References King, Mak and Riccio, Michael J. Military Satellite Communications: Then and Now. Crosslinks Magazine. Aerospace Corp. Spring, 2010. External links U.S. Air Force fact sheet on MILSTAR MILSTAR 3 / Advanced Extremely High Frequency (AEHF) Communications satellites Post–Cold War military equipment of the United States Lockheed Martin satellites and probes Military space program of the