The US Navy has accepted Lockheed Martin's fourth Mobile User Objective System (MUOS) satellite after the recent completion of on-orbit testing.
The MUOS-4 is the fourth out of five planned satellites the company is due to deliver to the navy. All the satellites support communications for mobile military forces.
It will join the MUOS-1, MUOS-2, and MUOS-3 after its relocation to on-orbit operational slot in 2016. MUOS-5 is scheduled for delivery in 2016.
Lockheed Martin narrowband communications vice-president Iris Bombelyn said: "MUOS-4 completes the initial constellation, providing the MUOS network with nearly global coverage.
"Mobile forces, equipped with MUOS terminals, will soon be able to communicate with each other, including voice, data and exchanging imagery; real-time, virtually anywhere on the Earth."
The MUOS network provides ground communications capabilities over existing systems, including voice, video, and data.
The satellites are equipped with a Wideband Code Division Multiple Access (WCDMA) payload, offering a 16-fold increase in frequency transmissions.
Each MUOS satellite features a legacy UHF payload that Lockheed Martin says is fully compatible with the existing UHF Follow-on system and legacy terminals.
The company said over 55,000 radio terminals can be upgraded to be MUOS-compatible, with only a software upgrade needed for several terminals.
Lockheed Martin Space Systems is the MUOS prime contractor and system integrator.
The US Navy's programme executive office for space systems and its communications satellite programme office are responsible for the MUOS programme.
Image: The MUOS-4 satellite completes the Navy's initial Mobile User Objective System (MUOS) secure communications constellation. Photo: courtesy of United Launch Alliance.