Lockheed Martin received a contract from the U.S. Air Force to build a third spacecraft for the Advanced Extremely High Frequency (EHF) satellite constellation.

Advanced EHF satellites, the successor to the Milstar system, will provide global, highly secure, protected, survivable communications for the U.S. Department of Defense.

Lockheed Martin Space Systems, Sunnyvale, Calif., is the prime contractor and is providing a militarized version of its A2100 spacecraft bus and the mission control segment, which will consolidate the Milstar and Advanced EHF satellite control and communication resource planning into a single, modernized mission control system.

Northrop Grumman Space Technology, Redondo Beach, Calif., is the payload integrator and provider of the payload processors, nulling antennas, inter-satellite crosslinks, RF antenna equipment, and phased array antennas.

Advanced EHF satellites will also feature an electric propulsion system, provided by Aerojet of Sacramento, Calif.