In what could prove to be a major breakthrough for people living in rural and regional Australia, CSIRO is developing wireless broadband technology that could operate using barely a quarter the number of transmission towers required by current systems.

"Analysis we've commissioned shows other wireless technologies, which typically operate at higher frequencies, would require four times as many towers," CSIRO ICT Centre Director Dr Ian Oppermann said.

CSIRO's first prototype Ngara access system currently gives six simultaneous users 12 megabits per second (Mbps) from the network to their home and 12 Mbps from their home to the network. It is being shown to decision makers in industry and policy this week.

"We feel symmetry is important as people interact more using bandwidth-hungry applications such as video conferencing - they could be working from home, participating in a lesson or visiting their doctor online," CSIRO ICT Centre Director Dr Ian Oppermann said.

"It's easy to see how these services would be particularly valuable in rural areas."

CSIRO's Ngara technology aims to bring wireless broadband access to people living beyond Australia's planned fibre network using existing broadcasting infrastructure and UHF spectrum, such as that left behind when Australian TV goes 100 per cent digital.

"Even with the analog TV switch-off, there won't be much spectrum to spare so any wireless system has to be very efficient, sending as much information as possible within its allotted frequency range," Dr Oppermann said.

At 20 bits per second per Hertz (20 b/s/Hz), CSIRO's Ngara access system is one of the most spectrally efficient in the world. The 12 Mbps, six simultaneous user system works in the space of one television channel, which is seven megahertz (MHz) wide.

During recent field testing from a Broadcast Australia tower in Tasmania, CSIRO's low-power prototype system operated over distances up to 16 kilometres.

"A feature of our first prototype Ngara system is that all six simultaneous users within the coverage area would have access to and from their homes at 12 Mbps," Dr Oppermann said.

"Current wireless technologies are not designed to allow uploads and downloads at the same rate and making them symmetrical would likely mean even more towers."

Ngara is a word of the Darug people meaning to listen, hear and think.The Darug people are the traditional owners of the land on which the ICT Centre's Sydney lab sits. This project is supported by the Science and Industry Endowment Fund. CSIRO acknowledges the assistance of Broadcast Australia.