Now hear this: Y. coming to aid of cellular

PROVO — Cell phones ring during movies, romantic dinners and even religious ceremonies, but that's not the only reason they're annoying.

Audio quality remains a problem — ever really hear a pin drop on the other end of a cell phone call? — and calls frequently drop when a cell phone tower is maxed-out on customers.

Researchers at Brigham Young University don't have a solution for people who won't turn off their phones, but they have found a way cell phone companies could double their capacity. It could be enough to make that special someone sound better, or at least keep her on the phone until you muster the courage to ask her out.

The technology could also be used to improve signal strength, which would improve battery life, but that wouldn't increase profits for the industry giants, one researcher said. Corporate pressure likely will lead companies to double the capacity of cell phone towers.

"You know AT&T and Verizon want more customers, so you know that's what they're going to do," said Michael Jensen, associate professor of electrical engineering.

But continued research could provide methods to increase cell phone capacity sixfold.

Jensen's team built a tiny antenna that can receive two separate radio signals over a single frequency. The antenna is similar to the kind attached to a cell phone's circuit board and would double the amount of information that could be transferred by a cell phone.

The key is bandwith, not the kind that makes a computer modem faster but the range of frequencies allotted to cell phone companies by the FCC.

"Cell phone service providers like Sprint PCS and Verizon have only a certain amount of radio bandwidth they can use for cell phone technology," Jensen said. "To accommodate the maximum number of customers, they make trade-offs in terms of a cell phone's vocal quality and the reliability of its signal.

"The resource is finite, the company needs to make a profit and they balance that with customer satisfaction."

The research was published Monday in "Transactions on Wireless Communications" by the Institute of Electrical and Electronics Engineers.

The BYU team's research was sparked by an article in "Nature" based on a theory developed by Lucent Technologies. The article said that the three polarizations evident in every radio wave double to six in heavily populated areas as the waves bounce off cars, walls, trees and other obstacles.

The new paper in IEEE uses a different theory to explain the same process, and the new antenna makes it possible for the first time to use two of those polarizations instead of one, said Jensen, who worked with postdoctoral researcher Thomas Svantesson and then-doctorate candidate Jon Wallace.

Manufacturers will be able to implement the technology without attaching additional antennas to cell phones, which would be too ugly, or increasing the weight of the phones.

"We've always been able to to do this 'magic,' but it would have required two antennas," Jensen said. "This takes a built-in antenna and makes two connections to it so we can get two streams of information."

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