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Mike Wright Telstra's wireless executive director, told iTWire that the main aim of the trial was to see if the parameters in the LTE specification could be 'tweaked' to enable it to operate over such distances.
As the distance from base station to device increases the time taken for either unit to receive a response from a signal sent the other increases. If this interval is beyond what is permitted in the standard, the system will not function correctly.
"When they write these standards they don't usually have a country like Australia in mind and it is a question of seeing if we can modify the standards easily to get it working," Wright said. "We had to make some software and configuration changes [in the network, not the device].
He added that Telstra had made similar modifications to earlier networks. "With GSM we extended that first to 35km, then to 70km and then to 100km. CDMA we took to 160km and Next G we have taken out to 200km'¦Most of our traffic is over less than 100km, because beyond that the curvature of the earth means you need special antennas, or you need to be in an aircraft."
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Were Telstra to implement LTE at the 850MHz frequency used by Next G, or in the 700MHz digital dividend band, it would have a much better change of getting satisfactory operation over long distances. Wright said it was too early to give any indication as to what frequencies Telstra might use.
He said there could well be overseas interest in Telstra's results. "We have seen some 700MHz digital spectrum being auctioned in other countries, and LTE is more viable over long distances at those frequencies."
Telstra has not yet revealed any results from trials with its other LTE trial partners, Ericsson and Huawei. Both of which are being conducted in metro areas.
"All the trials are about understanding LTE capabilities, limitations and performance to feed into our network planning," Wright said.
A key question is performance under load from many users, and Wright said: "We can model that mathematically, and some of the vendors are able to generate artificial loads on the network."