The fourth in a Lockheed Martin-built five-ship fleet for a next-generation, narrowband tactical military satellite communications system was officially accepted by the U.S. Navy this week, following successful completion of the satellite’s on-orbit testing. Launched on Sep. 2, the 7.5-ton Mobile User Objective System-4 (MUOS-4) satellite extends a new, $7 billion secure military communications network (MUOS) for U.S. military forces on the move, expanding the network’s coverage now around nearly the entire planet.
With on-orbit testing now complete the satellite is ready to relocate to its 22,000-mile-high on-orbit operational slot in preparation for operational acceptance next spring.
“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,” said Iris Bombelyn, Lockheed Martin’s vice president for Narrowband Communications. “This is a tremendous upgrade in communications capabilities over what currently exists for our nation and our allies.”
MUOS operates like a “smart phone cell tower in the sky,” supporting a worldwide, multi-service population of users in the UHF band, providing increased communications capabilities to smaller terminals while still supporting interoperability with legacy terminals. The new military SATCOM system will, for the first time, give MUOS Wideband Code Division Multiple Access technology users beyond-line-of-sight capability to transmit and receive voice and data using an Internet Protocol-based system, giving users greater mobility, higher data rates, and improved operational availability.
The Government Accountability Office (GAO) said earlier this year that the unique MUOS ultra-high frequency multi-service capability can not be fulfilled until the program fully solves waveform communications software issues that have significantly delayed operational use of the spacecraft’s most advanced capabilities.
More than 90 percent of the MUOS capabilities remain underutilized, according to Christina T. Chaplain, GAO’s Director of Acquisition and Sourcing, speaking before a Senate Armed Services subcommittee in April.
MUOS program manager, Navy Capt. Joe Kan (pronounced Con), told AmericaSpace he did not agree with that statement, stating that U.S. military services are conducting highly successful tests around the world, including in the Arctic and Antarctic with MUOS radios through the first three MUOS satellites parked over the equator covering the Atlantic, Pacific, and CONUS. MUOS-4 is parked over the Indian Ocean.
“The MUOS program faces challenges that prevent full use of its satellite capabilities,” Chaplain testified. “The Issue is related to the development of the MUOS waveform [UHF radio software] meant to provide increased communications capabilities beyond those offered by the [earlier Boeing] UHF legacy system.” The Boeing satellites were launched between 1993 and 2003.
The waveform issues have “caused delays in the use of radios being developed by the Army as the first operational terminals to incorporate the MUOS waveform. Use of over 90 percent of MUOS’ planned capability is dependent on resolving problems with integrating the waveform, terminals, and ground systems.” Chaplain testified. The 10 percent that is operational involves the MUOS legacy system that is providing continuous service to users operating lower data rate UHF systems with the aging Boeing satellites.
“The MUOS program extended testing to fix software and reliability issues with the waveform integration and now plans to complete operational testing by November 2015—a 17-month delay from the initial schedule estimate. As a result, the Army’s plans to field its MUOS-compatible radios have now slipped from 2014 to 2016, roughly four years since the first MUOS satellite launch,” Chaplain told the subcommittee.
Lockheed Martin has since confirmed in a phone call to AmericaSpace that operational testing was in fact completed last month, and noted that the DOD’s Multi-Service Operational Test and Evaluation (MOT&E) results should be released sometime early next year.
By operating in the UHF frequency band, which is lower than that used by conventional cellular networks, MUOS will provide U.S. and allied warfighters with the tactical ability to communicate in “disadvantaged” environments, including heavily forested areas where higher-frequency signals would be otherwise impaired. Even troops in buildings with no satellite access are expected to see an increase in communications capability.
The size of the MUOS satellites are a result of the nature of the size of the UHF waveform, and, at 15,000 pounds each, their weight is due to the fact that—besides requiring bigger hardware for UHF—they are designed to operate from GEO for an expected 15 years, and so they need a lot of fuel.
MUOS is an IP-based communications protocol based on 3G, which gives military users on the move more communications capability over existing systems, including simultaneous voice, video, and data—similar to the capabilities experienced today with smart phones, providing users with 10 times more communications capacity.
With MUOS-4 ready to go operational next spring Lockheed is busy preparing the next satellite of the constellation for launch In May or June of 2016, MUOS-5, which will actually serve as an on-orbit spare and is currently in final assembly and testing at Lockheed’s satellite manufacturing facility in Sunnyvale, Calif. Once ready the satellite will fly to Florida on a C-5 Galaxy (courtesy of the 60th Air Mobility Wing of Travis Air Force Base) for final preparations and launch, which will take place from Cape Canaveral Air Force Station Space Launch Complex-41 (SLC-41) atop a ULA Atlas-V 551 rocket—the most powerful configuration of the Atlas-V.
“This is another major step toward achieving a fully operational MUOS end-to-end capability by 2016,” said Navy Capt. Joseph Kan, the MUOS program manager. “The Navy, in close collaboration with the Army, Air Force and our industry partners, is bringing the future of worldwide mobile satellite communications into reality for the United States and potentially allied nations.”
The MUOS satellites represent some of the heaviest payloads ever to be launched by ULA’s Atlas-V, second only to Orbital ATK’s new and improved Cygnus spacecraft, which is currently waiting for bad weather to clear central Florida in order to launch to the International Space Station with over 7,000 pounds of supplies, equipment, and experiments. The spacecraft itself, along with its full payload, weighs over 1,500 pounds more than the Navy’s MUOS satellites.
– Written by Mike Killian and Craig Covault
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