LTE pull is capacity, not speeds: Telstra

Key Telstra executives this morning emphasised that its newly announced Long Term Evolution (LTE) roll-out was about freeing up capacity on its flagship Next G network, rather than just boosting top-line speeds.

At Mobile World Congress in Barcelona last month, Telstra announced that it would install LTE in mobile towers within the CBDs of all Australian capital cities and selected regional centres by the end of 2011. To do so, Telstra will use the 1800MHz spectrum, running the LTE service alongside its existing 850MHz HSPA+ technology, with users able to switch between them.

Mike Wright, Telstra's executive director of Networks & Access Technologies (Wireless), told journalists that the overarching theme at Mobile World Congress had been the need to manage the demand for mobile bandwidth. With mobile data usage typically doubling "every 12 months", telcos were struggling to cope.

The executive said LTE had typically been discussed in terms of being "a new network". But he saw the technology more as giving Telstra a "hybrid" network, rather than a whole new separate network.

Wright and Telstra chief technology officer Hugh Bradlow pointed out this morning that by far the biggest consumers of data on Telstra's network were customers with USB dongles connected to their laptops, despite the fact that they existed in smaller numbers than smartphone users.

To keep the service operating at a high level, Telstra plans to start selling dual-mode LTE/HSPA+ mobile broadband modems, which will allow those users to use both the existing 850MHz (HSPA+) and planned 1800MHz (LTE) frequencies in areas that support them. When those users range off HSPA+ onto LTE, Wright said, they will free up HSPA+ spectrum and bandwidth for other users.

Advancing network technology, the executive pointed out, "doesn't always mean maintaining higher peak speeds".

"It's a step change in what we're putting on the network," Wright said. "But it's also about maintaining the network performance."

Even if the upgrade was just about speeds, handsets were behind the game, according to the telco.

Telstra's Next G network has already pushed past a 42Mbps theoretical limit in some areas, but Bradlow noted this morning that the telco was only now starting to see smartphone handsets available with chipsets that could do 21Mbps and 42Mbps speeds, with most still focusing on the legacy 7.2Mbps limit.

The telco doesn't expect the first LTE handsets at 1800MHz to be available for a while yet, with Bradlow guessing they could arrive within the next 12 to 18 months.

Fostering interest in 1800MHz

Telstra's shift to the 1800MHz spectrum for LTE mirrors the approach the telco took when it rolled out its 850MHz Next G network in late 2005. At the time, the telco was questioned for using a spectrum frequency which was unpopular with international telcos — with some claiming few handsets would ever support the range.

However, since that time, a number of other telcos around the world have introduced the 850MHz spectrum on their networks, and it is common for handset manufacturers to support 850MHz by default.

Wright said Telstra had noticed that interest in 1800MHz was "growing" around the world, and that it was beginning to emerge as a standard, with chipsets in development and vendor partners (Telstra has partnered with Qualcomm, Ericsson and Sierra Wireless) beginning to emerge.

Telstra, he said, had "essentially created a global interest group" around 1800MHz LTE and had hosted a session on the standard at Mobile World Congress, which was attended by about 70 CTO-level executives.

"The feedback from that session was very positive," he said, noting that he would be surprised if Telstra remained the only telco with a "hybrid" HSPA+/LTE network.

"I think a lot of people have been thinking about it and talking about it," the executive added.

"We said: 'Why can't we be the catalyst?' And once we started having the discussion, we found — hey presto! — a lot of people agreed with us. It's not that different from when we launched Next G ... [we had] a user group at that stage also."

Bradlow said that in the future the spectrum band a provider uses will be less important than the number of bands used. He expected future handsets to be capable of utilising up to 12 bands.