Telstra has achieved 300 Mbps speeds in a test on its 4G network by aggregating two channels of 20 MHz spectrum.
Telstra was testing a technique called LTE Advanced (LTE-A) carrier aggregation, which allows greater data download speeds by combining spectrum across two separate spectrum bands. The test aggregated 20 MHz bandwidth from the 1800 MHz band and another 20 MHz from the 2600 MHz band.
The 300 Mbps speeds were achieved in a trial environment; actual speeds for users will be lower.
Telstra's executive director of networks, Mike Wright, wrote on the Telstra blog that the trials "build on our earlier LTE-Advanced work and set us up to continue to deliver a reliable network experience and more reliable speeds into the future".
Telstra will refer to the trials next year as it develops its network and prepares to launch devices that combine its 700 MHz and 1800 MHz spectrum holdings, he said.
Last month, Telstra released its first 4G device supporting LTE-A, a Wi-Fi hotspot, which can aggregate spectrum in the 900 MHz and 1800 MHz bands.
LTE-A is not yet available in most places where Telstra has 4G coverage. Telstra has LTE-A coverage in one region of the Sunshine Coast, Queensland. Wider rollout of LTE-A coverage is expected after Telstra rolls out the 700 MHz spectrum that it won in the recent Digital Dividend auction.
Telcos may begin to use the 700MHz band on 1 January 2015. The band must first be cleared of its existing broadcasting users.
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