DOD builds foundation for future SATCOM
New communications satellite network will boost bandwidth while helping reduce terminal sizes
Delays have plagued the Mobile User Objective System (MUOS) satellite communications system, but the Defense Department and its suppliers are now gearing up for deployment. The narrowband military satellite network will support U.S. and NATO military operations worldwide, increasing bandwidth, improving security and aiding the drive to move smart phones into the field.
The first satellite in the MUOS constellation was supposed to launch in 2009, but it was delayed until early 2012. Now, the Navy predicts that the MUOS constellation – four satellites and an on-orbit spare – will achieve full operational capability in 2015. MUOS will replace the Ultra High Frequency Follow-On system and give mobile warfighters improved communications capabilities such as simultaneous voice, video and data.
The moves are part of a broad DOD program designed to increase bandwidth and security while replacing aging hardware. That initiative, which includes the Advanced Extremely High Frequency (AEHF) network, will continue with a number of satellite launches over the next few years.
“We expect MUOS-2 to launch in the third quarter, and complete global coverage should be in place by 2015,” said Mark Pasquale, vice president and deputy of military space programs at Lockheed Martin. “A fifth on-orbit space will be delivered to orbit in 2016. AEHF-3 is slated for a late third-quarter launch, and its six satellites should be in place by 2018.”
Pasquale noted that the satellite scheduled to be placed in orbit this year completed testing in January and is now in storage awaiting launch. MUOS uses a Wideband Code Division Multiple Access (WCDMA) cellular phone network architecture that provides a 16-fold increase in transmission throughput compared to the legacy system. It also will add global connectivity through the Defense Information Systems Network and support services such as full, two-way voice and data transfers.
“A single MUOS satellite will provide four times the capacity of the entire legacy constellation of eight satellites,” said Steven Davis, a public affairs officer at the Space and Naval Warfare Systems Command (SPAWAR). “Each MUOS satellite also includes a legacy UHF payload that is fully compatible with the current system and legacy terminals. This dual-payload design ensures a smooth transition to the WCDMA technology.”
Though representatives of DOD and prime contractor Lockheed Martin are bullish about the program, critics note that delays and cost overruns have diminished much of the luster of the effort. The multibillion dollar program is about two years behind schedule. As a result, DOD has had to contract with Australia for some UHF coverage and use more commercial satellite bandwidth than originally planned.
Although MUOS is finally moving forward, commercial communication suppliers haven’t slowed their launches . For example, Intelsat 22 was launched last year, carrying 40 X 25 kHz UHF channels designed to augment MUOS. The UHF payload is compatible with the UHF Integrated Waveform planned for use on MUOS.
Those involved with MUOS say that while launches and connectivity have been delayed, the system is now providing communications capability with higher levels of security than are currently available.
“Now that our customers are gaining access to this additional capacity, they can reduce costly commercial SATCOM leases,” Pasquale said. “These commercial transmission systems don’t provide the same communications security to prevent eavesdropping and are seldom jam-resistant to the degree our customers demand. Moreover, MUOS represents 16 times the capacity of the satellites the constellation replaces.”
On the ground
As satellites complete testing and come on line, the focus is shifting to terminals, which are undergoing testing .
“From our standpoint, fielding MUOS-capable AN/PRC-155 two-channel Manpack radio is the first step to fully using these satellites,” said Scotty Miller, a vice president of secure communications and computing technologies at General Dynamics C4 Systems. “With the July 2013 launch of the second MUOS satellite, the government will be able to use the two-channel Manpack radios with the MUOS upgrade kit in real user tests as early as September.”
As the terminals move into production, they will be deployed in many different areas. One important attribute of the network is that warfighters can use the satellites regardless of where they’re positioned.
“Whether for vehicles, ships, submarines, aircraft or service members dismounted and on the move, this system was designed to provide voice and data communications services both point-to-point and through netted connections,” Davis said. “A warfighter will be able to make a telephone call over a MUOS terminal and send about 10 times more data than they can now.”
Another critical aspect of the technology is its ability to support warfighters while they’re on the move. MUOS doesn’t require the precise positioning associated with existing satellite links, which requires that users be stationary with an antenna pointed directly towards a satellite.
“MUOS will allow users to be mobile while communicating and to send data at 10 times more capacity than now by adapting a commercial 3G wideband cellular phone network with geosynchronous satellites,” Davis said.
That trait will be attractive to the many military planners who hope to take advantage of smart phones and tablets. Many strategists want to let warfighters leverage the rapid technological advances of these compact handhelds so they can reduce the load carried deep into the field. Any reduction in antenna size will be a huge benefit for these programs.
Though MUOS terminals will continue the drive toward smaller electronics, users also will see improvements in communications. Using cell phone techniques opens the door for simultaneous transfers of voice and data.
“It is important to note that the MUOS waveform is full-duplex, which means users can carry on a conversation as you would on a cell phone, rather than [is the case with] most legacy radios that are half-duplex, where only one person talks and everyone else listens,” Miller said. “Our HMS PRC-155 two-channel Manpack was built to accommodate this full-duplex capability.”
It will be awhile before a substantial number of terminals make their way into the field. The U.S. military has deployed more than 18,000 narrowband terminals, according to the Communications Satellite Program Office.
General Dynamics, which is shipping the only product that has placed calls through the entire MUOS ground infrastructure, won’t make a shipment of more than 100 terminals until fall. That shipment will come after on-orbit tests in March and a subsequent basic system checkout consisting of point-to-point and point-to-net (voice and data calls).
While the number of suppliers is limited at this point, terminal providers are watching the evolution of the constellation and its land-based elements. Harris RF Communications plans to upgrade some of its Falcon III radios to include the MUOS waveform, while Raytheon is working with the Army to redesign its ARC-231 radio so pilots can use MUOS. Other providers are also developing strategies.
“The challenge with our ground system designs and services is to be flexible and work with the availability of these new networks and have options where they are currently unavailable,” said Ben Brown, business development manager for DRS Technologies’ Satcom programs.
That job has become easier in recent months, now that the MUOS waveform is available. It uses IP versions 4 and 6 (IPv4/IPv6) so warfighters can connect to the Global Information Grid regardless of where they are.
“In January, Lockheed Martin delivered the MUOS software waveform,” Davis said. “That will enable military satellite communications terminal providers to deploy equipment that takes full advantage of enhanced MUOS capabilities.”