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communications
January 2008
Promise of ‘Revolution’ in Satellite Communications Faces Challenges
By Stew Magnuson with additional reporting by Sandra I. Erwin
 ORLANDO, Fla. — On Oct. 11, the Air Force launched the first of five Wideband Global Satcom spacecraft, marking the first in a series of four constellations that will revolutionize the military’s ability to communicate with forces on the ground, Air Force officials have said.
Part of an overarching strategy, the transformational communications architecture, the Defense Department is promising thousands of times more bandwidth by the middle of the next decade.
But as often is the case whenever it comes to the tricky business of space systems, there are technological and bureaucratic hurdles to overcome. And satellite acquisition programs do not enjoy a good reputation after several projects fell behind schedule and exceeded their cost estimates.
The Air Force has reformed satellite acquisition processes by adopting a “block” approach. This involves measured steps deigned to prove new capabilities before the satellite is launched. A Government Accountability Office report released in August generally gave this strategy good marks, however, it warned of an impending budget crunch. The Defense Department’s investment for all major space acquisitions is expected to rise over the course of the next three years from $6.3 billion to $9.2 billion, a 46 percent jump, GAO said.
One of the four planned space communications systems, the Transformational-Satellites, better known as T-Sat, may be the first victim of this budget crunch. Defense appropriators slashed its funding for the 2008 cycle.
Maj. Gen. Jeffrey Sorenson, special assistant to the secretary of the Army and the service’s chief information officer, said the Air Force has gotten lucky because some of the current communication constellations are surviving beyond their expected lifetimes.
“From an Army perspective, from a joint force perspective, we just can’t continue to rely on luck … We need to maintain schedules,” he said.
The following is a look at the four constellations, their capabilities and when they’re expected to go into service.
Wideband Global Satcom. In-flight check-outs on the first WGS, formerly known as the Wideband Gapfiller Satellite, are expected to be completed in January. The manufacturer, Boeing Co. will hand over the satellite to the Air Force then. At that moment, it will become the military’s highest capacity communications satellite.
Boeing is under contract to build five, with launches scheduled every eight to 10 months.
In a unique arrangement, the Australian military has signed a contract to buy a sixth satellite. This will allow its forces to use one-sixth of the constellations’ global capacity from the outset of the program.
Each satellite will have 3 gigabytes per second of capacity, 18 moveable spot beams employing X- and Ka- band transponders with on-board channelizers that will that will allow signals to switch between the two bands. In other words, a signal can be transmitted from an unmanned aerial vehicle to the satellite in Ka-band and relayed to a headquarters in the X-band, said Marc Johansen, director of space and intelligence systems at Boeing Co.
“This is going to be a major improvement in terms of our wideband communications,” he said.
They will replace the aging fleet of defense satellite communications systems III (DSCS III), which has been called the “workhorse” of military communications satellites, but are based on 1980s technology.
The first WGS will have a footprint over the Pacific, reaching roughly from the West Coast of the United States to China. The second spacecraft to follow later this year will cover the Middle East, Johansen said.
Advanced EHF. The first of three advanced EHF satellites, designed to augment, and eventually replace, the current Milstar constellation, is scheduled for launch in late 2008.
The Space and Systems Center in Los Angeles Air Force Base and contractor Lockheed Martin completed systems tests in October that ensured that the spacecraft will be compatible with ground terminals. It will provide data rates up to 8 megabytes per second. The three-satellite constellation will provide 10 times the transmission capacity as the Milstar’s five spacecraft, according to Air Force fact sheets.
Advanced EHF will link commanders to ships, submarines, aircraft and ground stations with encrypted, secure communications designed to continue working during a nuclear conflict.
Congress during the last two budget cycles has expressed interest in funding a fourth spacecraft to augment the military’s communication capacity as it awaits the development of the T-Sat.
Lt. Gen. Michael Hamel, commander of space and missiles command, said extending the program might cause significant production and engineering challenges. Among the issues is whether the parts would be available since the service only planned for three satellites. “We are looking at how we would go about doing that,” he said.
Mobile User Objective System (MUOS). The MUOS satellites, slated for launch in 2010, require new terminals that were scheduled to be developed under the Joint Tactical Radio System. However, JTRS has run into technical setbacks, funding delays and may not exist for several more years.
The Navy, which oversees satellites that use narrowband communications, has not synchronized with the Army the deployment of the satellites to the development of the JTRS terminals, said Bryan Scurry, director of operations at the Navy’s program executive office for space systems, at the Milcom conference.
The Defense Department ordered that the MUOS satellite also connect to the global information grid so users can access the Pentagon’s proprietary networks such as SIPRNET and NIPRNET. The capability has been built into the satellites, but the Defense Information Systems Agency has yet to come up with a connection into ground-based teleports to support that capability.
Scurry said network connectivity was a “requirement without funding.” DISA has no financial authority over the services, and no money of its own so far to solve the teleport problem.
The narrowband system will not be a white elephant for the foreseeable future because of the failing health of the ultra-high frequency follow-on communications (UFO) satellites that they are designed to replace, he said.
MOUS will have legacy payloads that will duplicate the UFOs’ capability. UHF is the only radio frequency that can penetrate clouds, foliage and urban structures.
The four planned MUOS satellites are due to begin launching at a rate of one per year starting in 2010, he said. That leaves a 15-month gap between the projected failure of the next UFO satellite and the first launch.
The newly opened Operationally Responsive Space Office under U.S. Strategic Command has been asked to provide solutions to the close this capability gap.
Scurry said if one more UFO satellite fails prematurely, there will be a loss of capability for troops in Iraq and Afghanistan.
About 85 percent of MUOS capability is intended for the Army and the Marine Corps.
The Navy is starting to “turn the tide” to push the Army to issue requirements to develop terminals and radios to support MUOS capability, Scurry said.
“The requirement wasn’t there, the funding wasn’t there … so we’re still at a roadblock as far as pursuing that terminal,” Scurry said.
“Once that capability gets fielded, then that capacity goes through the roof,” Scurry said. One MUOS will equal 10 UFO satellites, he said.
“We need to get those terminals moving faster and fielded much quicker than we are currently projected.”
Sorenson said, “We’re still working, trying to figure out what is that interface is going to be. What is that soldier going to walk around with to basically take advantage of that capability?”
“We still have some work to do,” he said without providing any timelines.
Transformational-Satellite (T-Sat). Scheduled to have its first launch as early as 2016, T-Sat is designed to dramatically boost the bandwidth that can be pushed to the lowest echelons by employing powerful Ku-band transponders and laser-based communications that are nearly impossible to jam.
The five-satellite constellation will support the Marine Corps and Army’s vision of space-based on-the-move communications, which entails sending and transmitting live streaming video to and from a humvee, Stryker or other vehicles as they speed down roads.
Johansen of Boeing Co., who is vying for the contract along with Lockheed Martin, said T-Sat could “revolutionize” satellite communications.
The decision on which of the satellite builders wins the contract may come as early December.
Meanwhile, Congress continues to question whether the Air Force should take money out of the T-Sat account and buy additional WGS or advanced EHF satellites.
T-Sat is a test of the “block approach” to developing satellites. The program calls for the services that will use the system to produce clear requirements, then for the builders to achieve technical milestones in increments before they proceed to the next block. Under this strategy, the first T-Sats to reach orbit will not have all the capabilities envisioned. Once the first blocks prove themselves in space, the second generation will become fully capable. This measured approach is designed to reduce risk and maintain a predictable schedule.
So far for T-Sat, the approach seems to be working, GAO found. Six of the seven critical technologies have been tested in relevant environment, it noted.
GAO warned that T-Sat will be one of the most costly and technically complex military systems ever attempted. It has a $14 billion to $16 billion price tag.
Please email your comments to SMagnuson@ndia.org
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