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BT mobile network hit by technical hurdles
Attack on mobile operators could be delayed until next financial year over fears calls will be interrupted in Wi-Fi 'handover'
BT’s return to the consumer mobile market could be delayed beyond the current financial year because of technical problems that undermine its plan to undercut rival operators, The Telegraph understands.
Sources said the company is struggling with technology that is meant to ensure that as much voice call and data traffic as possible is carried over Wi-Fi networks rather than a 4G mobile network.
Getting the technology right is essential to keeping the cost of providing the service down so BT can undercut traditional mobile networks. The more traffic that is carried over 4G, the more the company will have to pay via its deal with EE, which has agreed to rent capacity to BT to fill in the gaps between its 5.4 million Wi-Fi hotspots.
It is understood that BT has hit trouble with the 'handover’ between Wi-Fi and the mobile network. It is meant to be seamless so that calls are not interrupted, but mobile operators have been grappling with technical challenges for years.
A source said: “The handover is absolutely essential for BT to do what it wants to do with mobile. It’s possible the launch will slip into the second quarter of next year now.”
The second quarter of the calendar year will be the first quarter of BT’s next financial year, meaning it would miss a self-imposed deadline to attack the consumer mobile market.
Discussing mobile plans at the company’s annual results in May, Gavin Patterson, said the new technology would make BT’s network “pretty cost effective”.
He said: “We think we’ll be able to get the majority of people’s usage onto our network. And where we can’t, they’ll be able to roam seamlessly onto the arrangement we’ve got with EE.
“In terms of the timeframe, the critical thing we’ve got to get right is the customer experience.”
It could choose to go ahead with the launch using only the EE network to begin with, though that would radically increase the costs.
A BT spokesman insisted on Sunday that the plans were still on track.
As well as trying to crack the handover problem on a large scale, BT is working on ambitious plans to further reduce the cost of the new network later on. It paid £186m for its own chunk of 4G radio spectrum last year, which it intends to use to make itself even less reliant on EE.
That plan, meant to be implemented by the end of next financial year, is also facing technical challenges. BT aims to turn its Home Hub router into a miniature 4G mobile mast to use the spectrum, but because several neighbours in a street may have BT broadband it needs to find a way to ensure the signals do not interfere with each other.