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home > May/June 2007 issue > article
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| Stan Barouh |
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| “Spectrum is a function of our operational scenarios. From Bosnia to the Persian Gulf wars, our dependence on spectrum has increased accordingly.” Badri Younes, Defense Department |
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DOD fine-tunes its spectrum strategy
By Greg Slabodkin
Special to Defense Systems
DARPA, DISA are working on solutions to help the department make better use of the crowded airwaves
Defense Department officials know that there is no simple solution to the spectrum crunch that bedevils their evolving battlefield communications strategies. One solution clearly is not likely: the availability of more spectrum.
In September 2006, the Federal Communications Commission completed the biggest, most successful wireless auction in its history. Grossing almost $14 billion, the auction offered the largest amount of spectrum suitable for deploying wireless broadband ever made available in a single FCC auction.
This spectrum is the kind of prime real estate for which DOD is competing with commercial industry. For DOD, the stakes are high. Spectrum is the lifeblood of network centricity. As military leaders develop new battle strategies that take advantage of mobile and wireless technology, their forces are becoming increasingly dependent on assured access to the radio spectrum.
Badri Younes, DOD director of spectrum management, said that during the past six years, the department has seen an approximately 30 percent increase in spectrum use.
“We believe that net-centricity will drive this need for spectrum even higher,” Younes said. “Spectrum is a function of our operational scenarios. From Bosnia to the Persian Gulf wars, our dependence on spectrum has increased accordingly.”
Paige Atkins, director of the Defense Information Systems Agency’s Defense Spectrum Organization, said some of the spectrum auctioned last year was previously reserved for federal and DOD use.
“The challenge is the explosion of commercial wireless technology and things like WiMax and Wi-Fi, and the need to accommodate those new technologies, which are encroaching on military spectrum,” Atkins said.
“We continually face the challenge of doing more with less or, at the very least, with the same amount of spectrum we have today,” she said. “Our requirements are growing similar to commercial industry, and we have an extremely challenging environment that’s getting more complex every day.”
“Do more with less” may sound like a cliché from the 1990s, but when it comes to spectrum, it is also a mission statement for several projects now under way across the department.
Sharing spectrum
The irony is that although all spectrum may be assigned, most spectrum is unused at any given time. Through its Next Generation (XG) communications program, the Defense Advanced Research Projects Agency is developing technology that will make unused spectrum available to those who need it.
“If you go and look in the allocation tables, you see that every single piece of spectrum is filled,” said Preston Marshall, XG program manager. “But when we go out and measure spectrum usage, what we see is that typically 2 percent to 6 percent are actually being used. That’s because we assign people the frequency, and chances are they are not using it at this moment.”
XG works by sensing holes in the airwaves — parts of the spectrum that may be already allocated or licensed but are not being used — and using those to build or adapt tactical communications networks that do not interfere with other users.
When it comes to operations, the technology essentially will take the “man out of the loop,” allowing networks to be set up much more quickly, without waiting for a communications planner to allocate spectrum.
“What we want to do with XG is treat spectrum like the Internet,” he said. “Everyone will be able to get access to the spectrum when they need it. But when they’re not using it, other people can be jumping in and out. The technology to do that, with a variety of different radios and users that perhaps don’t want to talk to each other necessarily but can still share the spectrum, is the technology that we are working on with XG.”
DARPA researchers believe they can increase spectrum utilization tenfold, providing more assured communications and greater wireless networking capacity. Rather than 2 percent or 6 percent utilization, they are aiming for more than 60 percent, which translates into “at least 10 times more devices in the spectrum on any one point on the ground,” Marshall said.
Marshall is quick to point out that the primary product of the XG program is not a new radio or anything that will supplant developments made through initiatives such as the Joint Tactical Radio System or the Warfighter Information Network-Tactical programs.
“We’re working very closely with programs of record such as JTRS and WIN-T to see how XG technology can transition into their programs.
It’s their call, not ours,” Marshall said. “We did not want to build another radio. There are lots of radios being sold to the military today, and there are a lot more on the drawing board. We want to develop a technology that can go into any of those radios, if they meet a certain level of technological sophistication and flexibility.”
Stuart Timerman, director of the Army’s Spectrum Management Office, attended an XG demonstration at Fort A.P. Hill, Va., in August 2006 and said he was encouraged by the results, which were the first for XG in a real-world environment, instead of a laboratory.
“We’re a very interested observer, and if DARPA is able to come to fruition with XG, we see areas where it could be applicable for future applications for the Army,” said Timerman.
Indeed, XG’s potential benefits might even be applicable to commercial wireless systems, said Kalle Kontson, vice president and chief scientist at Alion Science and Technology. Before any of that happens however, spectrum managers must first address some tricky policy issues.
“Effectively, XG comes along and says to spectrum owners, ‘While you’re away and not looking, I’m going to swim in your
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| Stan Barouh |
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| “We’re still learning lessons from the CJSMPT JCTD and from the analysis of alternatives that will largely define the to-be state of Gemsis, because it hasn’t been fully defined yet.” Paige Atkins, Defense Information Systems Agency |
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pool in your own backyard on your property,’ ” Konstson said. “The spectrum holders that are protected by the existing policies take a dim view of that, and they want certain assurances that their rights are protected. So there’s a huge policy transformation that’s about to occur, and it’s pressured by technologies like XG.”
In the meantime ...
XG, however, is still a work in progress. That leaves military officials looking for immediate solutions to their spectrum problems.
That was the impetus behind a three-year Joint Concept Technology Demonstration (JCTD) started in mid-fiscal 2006 to automate the planning and management of spectrum in the battlefield.
The software being developed, dubbed the Coalition Joint Spectrum Management Planning Tool (CJSMPT), will provide warfighters with a real-time, 3-D view of the radio frequency being used in the battlespace, which will make it easier for them to decide how best to allocate spectrum.
For example, military forces in Iraq have run into a problem in which the technology they use to jam improvised explosive devices also interferes with other communications systems. CJSMPT will help them avoid that.
The system also will feature a simulation component that can predict and visualize potential interference from mobile forces.
“In the short term, CJSMPT will immediately optimize spectrum use to mitigate the effects of jamming on coalition military systems,” said Bill Kline, CJMSPT principal investigator for Advanced Technology Laboratories. “In the long term, it will provide an automated planning tool to manage battlefield spectrum much more efficiently.”
Sponsored by the U.S. European Command with the direct involvement of U.S. Central Command, the program office is expected to begin delivering and demonstrating software in fiscal 2007 and 2008, with final development and demonstrations expected by December 2008.
In September 2006, the U.S. Army Communications- Electronics Research and Development Engineering Center awarded Lockheed Martin a $5.2 million contract, with options, to develop CJSMPT.
The first phase of this program calls for the development of a software tool that partially automates the process of identifying and resolving potential spectrum conflicts. The Army plans to deliver this tool to the theater in southwest Asia to meet urgent requirements for dealing with conflicts and jamming in critical communications. A fully automated tool will be deployed to all coalition forces in a subsequent phase.
Steps toward a common picture
Eventually, CJSMPT could become part of a longer-term solution.
DISA is looking to establish a “program of record” for developing a spectrum management automation architecture and guiding current and future efforts to automate spectrum management, Atkins said. CJSMPT is just the first step in that direction.
The likely candidate for that work is the Global Electromagnetic Spectrum Information System (Gemsis) program.
Gemsis, as it is now envisioned, would provide commanders with a more comprehensive common picture of how spectrum is being used by both friendly and hostile forces, while transparently resolving potential spectrum conflicts created by competing mission requirements. This would make it much easier for military planners to plan and adapt spectrum use.
But the project is in its early stages. DISA is currently in the process of defining requirements and a concept of operations for Gemsis, while also analyzing alternatives, Atkins said. The program does not yet have any official milestones, but DISA has hired a contractor, Data Systems Analysts, to help with the work.
The department also needs to submit a “new start letter” to Congress. Until the program is officially approved, its budget will be limited. For now, the funding covers development of the acquisition documentation and support for the CJSMPT project.
DISA, meanwhile, is trying to get a better idea of the work to be done.
“We’re still learning lessons from the CJSMPT JCTD and from the analysis of alternatives that will largely define the to-be state of Gemsis, because it hasn’t been fully defined yet,” Atkins said. “That will help us address the hurdles and risks associated with achieving our goal.”
There are numerous hurdles. The politics of spectrum management are complex, in both the United States and the international community. As DOD develops new strategies for planning and executing military operations, “there will be significant challenges to ensure we effectively integrate the complexity of systems, processes, and the policy and regulatory environments to support our mission requirements on a global scale,” Atkins said.
From a policy standpoint, Gemsis is in line with the direction and policies that DOD has laid out to date, said Atkins, who oversees the Defense Spectrum Organization, a center for excellence in electromagnetic-spectrum analysis, planning and support.
A convergence of solutions
DISA continues to refine the DOD Electromagnetic Spectrum Management Strategic Plan and is documenting the department’s enterprise architecture for spectrum management, known as the Defense Spectrum Management Architecture. However, DISA will continue to refine both the policy and Gemsis as they move forward, keeping the two tightly coupled.
One variable, of course, is DARPA’s XG program. Such technology advances will not solve all of DOD’s spectrum problems, but they are expected to figure large in the solution.
“XG-like technologies and dynamic spectrum access technologies, in particular, are extremely important to our vision of spectrum management transformation,” Atkins said. “The movement toward those kinds of capabilities coupled with Gemsis is how we are laying out our strategy and enterprise architecture moving forward.”
Younes concurs that XG is not the spectrum management solution but an element of an overall system.
“Technology will need to evolve even further to allow GEMSIS to have its full potential in 2020 and beyond,” he said.
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