Developers are dealing with the military's need for greater satellite bandwidth by launching new satellites and using technologies that more fully utilize available links.
Although overall defense budgets are being trimmed, there’s little slowdown in the drive to provide more satellite bandwidth. User demand continues to rise, and developers are providing it by using two techniques; launching satellites and using technologies that more fully use available links.
The Defense Information Systems Agency (DISA) and the General Services Administration (GSA) plan to award $5 billion in satellite communications services contracts that will run for a decade. These Future Commercial Satellite Communications (COMSATCOM) Services Acquisition (FCSA) contracts underscore the ongoing shift to commercial providers.
These providers are responding to the demand with multiple launches. For example, Intelsat plans five launches during the next 18 months. Many of the commercial launches use new bands that offer higher power bands that carry more signals.
While new satellites go into orbit, providers also are moving to get more out of them. Engineers continue to develop new encoding and transmission techniques to squeeze more bits into each channel. For example, digital video broadcasting – satellite -- second generation (DVB-S2) improves the ability to send audio and video by about 30 percent without changing a satellite transponder’s bandwidth or emitted signal power.
“MTN has been utilizing advanced DVB-S2 changes within our various satellite networks to allow for the increases in throughput without having to increase physical satellite bandwidth which is, in most cases, unavailable for normal growth in key areas of operations,” said Richard Hadsall, MTN Satellite Communications’ chief technology officer.
As these new technologies increase bandwidth, COMSATCOM providers also are finding new ways to make it more adaptable. Conflicts may break out in different areas, and military officials are often generous about sharing bandwidth when natural disasters strike in areas that can’t be predicted.
“The Boeing-built Global Xpress satellites have the ability to put extra capacity in hot spots to meet unforeseen demand,” said Peter Hadinger, president of Inmarsat Government Services.
He said the terminals that receive signals play an important role in improving overall bandwidth. The Global Xpress terminals use an iDirect modem with a combination of high-efficiency DVB-S2 forward link waveform and efficient time division multiple access return waveform as well as adaptive modulation and coding to optimize channel use.
Though the locations may change, the military’s demand for satellite communications shows few signs of slowing down.
“So far, bandwidth demands have not decreased in Southwest Asia, but may plateau in the next twelve months,” said Andrew Ruszkowski, XTAR’s global sales and marketing vice president. “As this growth begins to slow, we already see growing demand in other regions, and in about 12 to 18 months this growth will potentially be at a faster rate than we have seen before, especially in regions including North Africa.”
The Defense Department's plans to extend communication capabilities further into the field are also driving demand for bandwidth. When individual warfighters under fire need to see the latest imagery from an unmanned aerial vehicle or other sensor, they will need reliable links that provide high speed. Although satellite bandwidth will be important, observers note that ground communications will play a major role as communications pushes towards the tip of the spear.
“Everyone wants to marry terrestrial communications with satellite communications,” said David Cavossa, Harris CapRock’s executive vice president and general manager of Government Solutions. “The most logical is to dismount from a Humvee with a VSAT dish and leverage that to communicate via satellite.”