CSIRO trials wireless broadband in the field
CSIRO has taken its prototype Ngara rural wireless broadband technology out of the lab and into the fields near the town of Smithton in north-west Tasmania.
The Ngara system is designed to bring broadband to people in rural and regional areas of Australia who live beyond the planned optical fibre network.
“We’re not going to get out of bed in the morning just to give people Internet access, it’s about giving people access to twenty first century services and allowing everyone to contribute to the digital world equally,” Dr Oppermann said.
Antennas mounted on existing television broadcasting towers would exchange signals with a slightly modified ordinary household TV antenna (there are some components in current antennas that prevent them being used as transmitters).
“About a month ago we showed the first half of the system working in the lab – what we call the uplink, going from your house to the tower. This week we have demonstrated it in the real world,” CSIRO ICT Centre Director Dr Ian Oppermann said.
CSIRO set up ‘user terminals’ at six farms around Broadcast Australia’s tower at Willis Hill, just outside Smithton. The farms range from 10 metres to 8.1 kilometres away from the tower, called the ‘access point’.
Each user terminal was simultaneously sending data at 12 megabits per second (Mbps). This data is in the form of a standard definition movie, video conferencing, an internet-based phone call and web browsing. All of this happens within one TV channel (which is seven megahertz wide).
Using only three watt antennas, the team had a user terminal sending high quality signals from 15.5 kilometres away (by way of comparison, TV transmitters typically use 40 kilowatts).
The reason CSIRO’s system can go so far on so little is because the information being sent is focused into a beam. This ‘beam-forming’ comes courtesy of the clever application of techniques called multi-user multiple input, multiple output (MIMO) and spatial division multiplexing.
The set-up in Smithton, which CSIRO is this week showing to leaders in industry and government policy is the first time these techniques have been used outdoors to users who are kilometres apart.
“This world first is testament to the tremendous efforts our team has made in the lab and here in Smithton,” Dr Oppermann said.
Of course, users also have to receive information and CSIRO does have the ‘downlink’ part of the system working, albeit partially.
“The team is only able to beam-form to one user at the moment, but this is an experiment, not everything is going to work on the first go. We are confident we will get there soon" Dr Oppermann said.
Find out more at: http://www.csiro.au/science/Broadband-to-the-bush.html