Labs set on 'cognitive radio' technology for Warfighter support
David Davis (left) and Alexander Pavlotskiy, of the Space & Terrestrial Communications Directorate, in the Software-Defined Radio lab.

FORT MONMOUTH, N.J. -- Radios have been a vital military technology since World War I. Advancing radio technology can provide quicker, more efficient communication in the field. Therefore, CERDEC technologists are developing a more intuitive device known as cognitive radio that will help prevent interference and provide a safe means of communication for the Warfighter.

In hostile environments, Soldiers are faced with difficult radio communication because of limited frequencies - many of which are jammed, compromising prompt and safe communication.

Cognitive radio is a form of wireless communication that allows transceivers to intelligently detect communication channels that are in use. By identifying these channels, the devices can make an immediate transition to vacant channels while avoiding occupied ones, thus aiding the Warfighter in finding accessible frequencies.

Cognitive radios can also be netted together to form cognitive networks that will provide better communication performance to the Warfighter with reduced Soldier intervention.

"Cognitive radio gives the radio enough intelligence to make its own decisions so that the user doesn't have to pick frequencies or plan a network," said Tim Leising, CERDEC electrical engineer.

"The first step is to enable them to actively find out their frequencies instead of telling the radios you can only use frequencies x, y and z. We're now saying you can use any frequencies you want except for 1, 2 or 3; it's more of an exclusion list. Basically, the radio will change how it works to enable better communications for the Warfighter."

Cognitive radio may be viewed as the next generation of software-defined radio (SDR). SDR software can mimic the functionality of older radio types or add new functionality, but cognitive radio will add intelligence to that functionality and capability.

"Because radios have been traditionally implemented in hardware, you've got AM radios, FM radios and VHF radios--that radio; that's all they can do. You can't change an AM radio to an FM radio. But what software-defined radio has done is extract the personality of the radio (AM, FM, VHF), and the software defines the personality. In a software-defined radio, the radio is the software, and the hardware is just the platform," said Jack Ruroede, branch chief of CERDEC's Ground Mobile Radio branch.

Since the summer of 2007, the Space & Terrestrial Communications Directorate SDR lab has been researching and developing cognitive radio. Its introduction to cognitive radio came from the first Department of Defense (DoD) implementation of the technology by the Defense Advanced Research Projects Agency (DARPA) and its Next Generation program.

"DARPA did a lot of research. They actually proved out some of these concepts where they had the software radio actively scanning different frequencies and finding what's occupied and not and acting upon that by using those frequencies," said Leising, lab team lead of CERDEC's SDR lab. "Our role is transitioning it into an actual product."
To reach this goal, the SDR lab has teamed up with the S&TCD Spectrum Analysis Division and the Network Sciences & Design Branch, to implement a lab that is accessible to all engineers and scientists working on the effort.

With these efforts, additional research and partnerships with academia and industry, cognitive radio has taken the forefront for the SDR lab team.

Sagor Hoque, electrical engineer in the SDR lab, was awarded a research grant from S&TCD in February 2008 to develop a cognitive reasoner, software that identifies which radio frequency may be occupied. During Hoque's six-month grant, he researched industry and academia to see what had been done in cognitive radio.
This led the way for a collaborative partnership this year with Virginia Polytechnic Institute and State University (Virginia Tech) to further develop a cognitive reasoner.

"We want to develop something that can work on a small-scale platform with very limited software resources. The plan is to demonstrate that on a small-scale software-defined radio, and we hope to do that by the end of the year," Hoque said
The SDR lab is also working with the Office of the Secretary of Defense to mature the technology and conduct additional research.

"We're developing some of the software on the software-defined radios that we have in the lab to enable future cognitive radio components," Leising said.

Rather than creating radio prototypes, the SDR lab is focusing its efforts on defining the small pieces of software in its existing SDRs. The goal, according to Ruroede, is to create a cognitive network, allowing tens or hundreds of radios on separate networks to coordinate and jump on the same frequency.

"When you've got 10 radios on our network, 10 radios on their network and 10 radios on another network, how does everyone coordinate this jump so that we don't have three networks trying to get to the same thing'" Ruroede said. "We're looking into not only cognitive radio but cognitive networking: how a bunch of these radios out in the field are going to work--together and in their separate enclaves."

The SDR lab has made a lot of progress with cognitive radio research, but Leising estimates a prototype is about five or six years away.

"As we continue our research, we're going to actually start to enhance our current SDRs with new hardware or new software to make them more powerful, more capable for future cognitive radio," Leising said.

"We have folks looking at the actual networking software. I believe by 2015, the CERDEC as a whole will be actually demonstrating a prototype of this, running all the different cognitive radios talking to each other."

The CERDEC S&TCD is formulating a Cognitive Networking R&D program for the next generation of cognitive software for cognitive radios.

Dr. Charles Graff, a senior engineer at S&TCD, said this effort will address the cognitive decision making for these radios in the Army's large-scale, mobile, ad hoc network environment.
According to Graff, the SDR concept has been around since the late 1980s, but it is only now that the advances in computer hardware and micro-electronics have made cognitive radio and cognitive networking possible for Army applications.

(This article appeared in Spectra, the magazine of the CECOM Life Cycle Management Command. To access the full issue in PDF format, 3.2 megabytes, click on the link appearing in the "Related Links" box at the start of the article.)

Page last updated Mon July 6th, 2009 at 17:10