UPDATE: Can we make radio interference into a virtue?

A University of Illinois researcher is trying the wireless equivalent of making a silk purse out of a sow’s ear.

The National Science Foundation has awarded Daniela Tuninetti a five-year, $400,000 grant to explore ways of using radio interference to improve wireless communications. Tuninetti is an assistant professor of electrical and computer engineering at the university's Chicago campus. She talked this week with Network World about her research.

“I remember my first course in communications,” Tuninetti says. “We called it ‘noise’ because we didn’t know what to do with that.”

But interference is not in fact a random phenomenon. “What I’m saying is that it is indeed a communication [between two radios], with a structure. And it can be exploited,” Tuninetti says.

To illustrate, she uses the metaphor of people talking among themselves at a party. Person A says something to Person B, but because of the sound level, B can’t understand it. A third person, standing between them, however, does understand what A said, and then repeats it for B.

This concept, applied to wireless, is now being called “collaborative communications” – a group of client devices cooperatively monitor the radio environment and share power, signal strength, signal processing and other resources to enable and support optimal communications. “You take advantage of the fact that everyone can ‘listen’ to everyone else, and then share things like a better signal quality to help others,” Tuninetti says.

“Interference, which is [in fact] a message, can be decoded to facilitate this communication,” she says.

One promising area for collaborative communications, which has been emerging as a hot research area over the past few years, is multi-antenna designs, such as those used in phased-array antennas and more recently in multiple input, multiple output (MIMO) radios. MIMO is the basis of the emerging 802.11n high-throughput wireless LAN standard, which will boost data throughput to well over 100Mbps and sustain high rates over much longer distances.