WASHINGTON — The U.S. Navy was forced to postpone the final certification test of its next-generation mobile satellite communications system to December 2015 because of problems integrating the system’s new radio frequency waveform with the ground segment and terminals, the service said in October report sent to lawmakers.
The Navy originally scheduled the so-called multiservice operational test and evaluation of its Mobile User Objective System, or MUOS, for April 2014. In March, Army officials overseeing part of the system told lawmakers that the test would take place in June.
But in a report to congressional defense committees Oct. 28, Sean Stackley, assistant secretary of the Navy for research, development and acquisition, said the test was rescheduled for December 2015 because of issues integrating the satellites’ waveform, ground system and radio terminal software.
The report said after initial tests in April, “system performance indicated more time was needed to mature” the capability of the digital payload before successful certification.
Built by Lockheed Martin Space Systems of Sunnyvale, California, the MUOS constellation is designed to provide smartphone-like communications to mobile U.S. forces at rates 10 times faster than the legacy system through a digital payload.
The digital payload employs a communications technology standard known as wideband code division multiple access or WCDMA. The MUOS satellites also have UHF payloads that are similar to those on the Navy’s legacy UHF Follow On mobile communications satellites.
The first two MUOS satellites launched aboard United Launch Alliance Atlas 5 rockets in February 2012 and July 2013. When fully deployed, the system will include four on-orbit satellites, one on-orbit spare and four ground stations.
In 2013, the Navy conducted an initial test involving the MUOS-1 satellite, two Manpack radios and a single ground station to demonstrate basic system functionality, the report said.
The final test will include two satellites, two ground stations, and multiple Manpack radios. Earlier this year, the Navy recognized it was not getting the “over the air performance improvement” it expected, the report said.
In the meantime, the service in May began putting the system through an increasingly complex test scenarios to find and fix software problems.
The program expects to achieve full operational capability in 2017 and the satellites are expected to provide service through 2025.
The slower-than-expected roll-out of MUOS’s advertised capabilities has gotten the attention of U.S. lawmakers.
In March, Congress’ watchdog agency, the Government Accountability Office, said more than 90 percent of the first satellite’s on-orbit capabilities are being underutilized because of delays with the terminal program.
The House Armed Services strategic forces subcommittee, in marking up its portion of the defense authorization bill for 2015, said it was “disappointed with this lack of synchronization in delivery of capability to the warfighter.”
The bill directed the secretary of the Navy and the Pentagon’s top acquisition official to submit a plan for accelerating the fielding of the terminals. The Senate
Armed Services Committee also had questions and asked for a report on the satellites’ ground system and associated terminals.
In response to the Senate provision, the Navy report said that about 12,000 MUOS compatible terminals are expected to be in the field by 2018 or 2019. By 2025, about 53,000 terminals will be online.
In the report, the Navy suggests retrofitting existing terminals to handle the new waveform would be significantly cheaper than buying new ones.
Meanwhile, the report also said the Navy plans to launch the fifth MUOS satellite, the on-orbit spare, in July 2016. A launch vehicle has not be selected and it is unclear whether the mission would be competitively awarded.
The third and fourth MUOS satellites are slated to launch aboard Atlas 5 rockets in January and August of 2015, respectively.
