Project aims to stop interference in wireless signals

By PETER GRIFFIN

With the Broadcast Communications versus Walker Wireless radio interference dispute buried with an out-of-court settlement, wireless providers are keenly aware of the headaches of spectrum management.

Engineers at Auckland University want to undertake a two- to three-year research project that will look at ways of isolating radio signals in built-up apartment and office blocks. Rather than study ways of modifying hardware to prevent interference, the engineers will investigate how building materials can be used to stop signals sharing the same spectrum interfering with each other.

The research will look at how wireless devices, whether they are cellular, Wi-Fi 802.11, Bluetooth or wireless monitoring systems, interfere with one another in built-up environments.

Professor Allan Williamson of the university's School of Engineering, said the risk of interference degrading wireless services was increasing as more devices communicated wirelessly.

"Any building owner will tell you that one of the big costs in the trade is refurbishing for data services. Increasingly, people are going for wireless systems because they are reconfigurable," said Williamson.

At its simplest form, that involved putting screens on intervening walls between offices, creating buffer zones.

"It's a conducting film that has apertures in it that are of the right size to let certain frequencies through but exclude others.

"It could almost be a copper foil lining the back of your GIB board, or aluminium foil on the back of wallpaper or vinyl," said Williamson.

The idea was to design materials that could be made cheaply enough to allow the retro fitting of existing buildings as well as installation in new buildings.

Finding a solution was easy, but finding one that was commercially viable was not, Williamson said.

The engineering department was seeking funding so it could proceed with the research.

It hoped to come up with commercial solutions to radio interference that could be exported.