Wireless technology currently in development by the CSIRO may be the key to bringing a cost effective National Broadband Network to regional and rural Australia, acczeording to the national science organisation.

The technology, dubbed Broadband to the Bush, is designed to make use of analogue television infrastructure already in place within Australia, Alex Zelinsky, group executive information and communication sciences and technology at the CSIRO said.

“What we are proposing to do is use the broadcast towers and UHF and VHF frequencies that will be left when analogue television is switched off,” he said. “The whole idea is that there is no comms gear in that space as it has been used for TV and we can reuse the broadcast infrastructure.”

In this way, wireless broadband would be available anywhere a current analogue television signal could be received, Zelinsky said.

The CSIRO’s technology uses orthogonal frequency division multiplexing (OFDM) – a modulation scheme used in wireless LAN standards such as 802.11g – and, multiple input multiple output (MIMO), which uses multiple antennas to transmit and receive multiple data streams.

Combined, the CSIRO’s OFDM-MIMO technology could offer significant efficiencies over existing wireless and prove to be a valuable addition for reaching the last 10 per cent of the population as part of the National Broadband Network, Zelinsky said.

“With normal wireless technologies you would need 36 base stations to cover what we can do with one, so you reduce your capital costs,” he said. “We believe [the broadcast range] could cover 100 square kilometers and at rates of between 12 and 50 megabits per second, but it could scale up to the full 100Mbps (equal to the proposed speed of the fibre NBN).”

Zelinsky acknowledged that wireless technology would likely continue to lag behind fibre in speed for some time, and be subject to some interference, but said the technology was rapidly improving.

“Wireless is always slower than wired, but wireless is always progressing - we have shown you can do wireless backhaul at six gig,” he said. “As time goes on the six gig will become 12 gig and so on. Invariably as you are not going through glass fibre, a sealed medium, there will always be some interference so it will be less reliable.”

While the technology’s use in the NBN would be reliant on the federal government agreeing to assign the UHF and VHF spectra for wireless broadband use, Zelinsky said there was potentially a global market for Broadband to the Bush.

“It’s a good opportunity for Australia, but China with it’s large population could use this technology, as well as south American and Africa,” he said. “We’ve had success with our Wireless LAN technology and this is another exciting opportunity.”

Zelinsky said field trials for the technology would likely occur in the next 12 to 24 months, with commercialisation expected in the next three to five years.