Radio receivers, such as those found in remote-controlled toys, wireless phones, cell phones, and wireless doorbells, are cheap, readily available devices that are often used to initiate the explosion in an IED, says Todd Hubing, professor of electrical engineering at UMR.

"At Fort Leonard Wood, Mo., we viewed IED training tapes and saw there are a lot of cases where command-initiated IEDs are placed on the side of the road in a very remote area," says Daryl Beetner, associate professor of electrical engineering at UMR. "If a military convoy was able to detect the presence of a radio receiver on the side of the road up ahead, they would be able to react accordingly before it could pose a threat."

Hubing, Beetner and other researchers in the UMR Electromagnetic Compatibility Laboratory are internationally recognized for their ability to track down the sources of unintentional noise in electronic systems for the purpose of minimizing radio frequency emissions. They are now using some of those same tools to detect and identify radio receivers.

One of the techniques Hubing and Beetner are using involves capturing the electromagnetic radiation from various radio receivers and slowing it down to make audio signals. Filtering, or pre-processing of the signals, is key to enhancing the sound of a particular receiver. By filtering out the normal background signals and emphasizing any new or unexpected signals, the equipment that they have developed gives a person the ability to "listen" for hidden electronic devices.

"It is relatively easy to override these radio receivers once they are identified," Hubing says. "An operator can be trained to recognize the sounds that different IED triggers make or artificial neural networks can be employed to detect various devices automatically." In recent tests, the system being developed at UMR detected and identified five different devices of the type commonly used to detonate IEDs with better than 95 percent accuracy.

The researchers are currently developing a device that can be mounted to a robot and used to detect and identify hidden radio receivers within a room or at close range. Eventually, they expect to have a device that can be mounted to the first vehicle of a military convoy to identify and locate potential IEDs up ahead.

This technology is not only useful for detecting radio receivers, but also other electronic devices such as timers and sensors. "Presumably we’d be able to detect the presence of anything electronic, particularly if it had a processor in it and there was a lot of electrical activity," Hubing says. "This project started as an effort to identify automobiles based on their radio frequency emissions. This turned out to be much easier than we anticipated. We shifted our focus to radio receivers when we learned of the urgent need in this area."

Listen to KUMR's feature on this research.