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Wireless System Complements NBN

By Stephen Luntz

CSIRO’s Ngara technology will use analogue TV channels to send and receive wireless broadband

CSIRO has hailed the success of a trial of a wireless broadband technology that it hopes will fill a niche in the National Broadband Network in areas too sparsely populated for fibre but more densely populated than areas that will rely on satellites.

CSIRO’s Ngara technology will use analogue TV channels to send and receive wireless broadband at a minimum of 12 Mbps per user to small clusters of homes. “Someone who doesn’t live near the fibre network could get to it using our new wireless system,” said CSIRO ICT Centre Director Dr Ian Oppermann.

The shutdown of analogue TV signals will leave a legacy of broadcast towers with line-of-sight transmission to home aerials, and Ngara will put these to use. “Even with the analogue 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,” Oppermann said.

Although similar technologies have been developed elsewhere, Opperman claimed: “Analysis we’ve commissioned shows other wireless technologies, which typically operate at higher frequencies, would require four times as many towers”. Ngara allows users the same 12 Mbps rate for uploads as downloads, making teleconferencing viable.

Field trials in Smithton, Tasmania, proved successful but Oppermann says it will be 2 years before the technology is commercially available. The challenge will be to make the cost of the transmission and reception boxes cheap enough to keep the technology viable, given that economies of scale in production may be limited. However, CSIRO hopes that the ready availability of well-placed transmission towers set up to broadcast at the right frequencies will keep costs low.