WASHINGTON — The U.S. Navy has formally accepted three of a planned four General Dynamics-built ground stations for its next-generation mobile communications satellite program, the company announced Jan. 23.

Designed to provide smartphone-like communications to mobile U.S. forces, the multibillion-dollar Mobile User Objective System (MUOS) ultimately will consist of four geostationary-orbiting satellites plus one on-orbit spare, and four ground stations. Lockheed Martin Space Systems of Sunnyvale, Calif., is prime contractor; General Dynamics C4 Systems of Scottsdale, Ariz., is providing the ground segment. 

The MUOS ground station in Wahiawa, Hawaii, was turned over in December 2012, followed by the Chesapeake, Va., ground station in March; both are now operational. The third ground station, in Geraldton, Australia, was turned over to the Navy in July.

All three are now staffed by Navy personnel, a General Dynamics press release said. 

Each ground station includes three 18.4-meter Ka-band antennas on 16.1-meter pedestals, and a centralized operations and control center.

Only the ground station in Niscemi, about 60 kilometers inland from the U.S. Naval Air Station Sigonella in Sicily, is left to be completed. Work on that site resumed in November after a six-month delay following protests sparked by concerns about harmful electromagnetic radiation that might be emitted from the antennas.

The first MUOS satellite was launched in February 2012. The second followed in July 2013.

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Mike Gruss is a senior staff writer for SpaceNews. He joined the publication in January 2013 to cover military space. Previously, he worked as a reporter and columnist for The Virginian-Pilot in Norfolk, Va. and The Journal Gazette in Fort Wayne, Ind. He...