High speed mobile phones face technical problems

BT Cellnet claims it will deliver a high speed mobile data service in the UK by next summer, despite lingering concerns about overheating handsets and short battery life.

Scientists at BT Cellnet's labs last weekend performed the first data call using general packet radio service (GPRS) over a live GSM mobile network. GPRS provides a constant mobile data connection at up to 115Kbps, although initial services are likely to offer much lower speeds.

However, unlike receiving data, sending data from a GPRS phone requires that large amounts of radiation are emitted from the handset to maintain a signal. This can cause overheating in the phone as well as rapid battery drain.

Motorola, which is supplying the handsets for BT Cellnet, said the heat issue will not delay handset rollout as it is only a problem when transferring large amounts of data upstream, something it says users will rarely do.

Dominic Strowbridge, communications division marketing manager at Motorola in the UK, told vnunet.com at the recent Telecom 99 show in Geneva: "If you try to use more timeslots in the uplink, then you get problems with heat and battery life.

"Symmetric applications, like large file transfer, ideally like as many timeslots as possible. Those aren't mass-market applications. We found that the vast majority of emails are answers like yes, no and hi," he said.

Mike Short, BT Cellnet's director of network strategy, said the issue has been overhyped and that it will be resolved in time for the company's planned rollout.

"Our terminals have to be properly tested. I still think there will be GPRS terminals ready by June next year," said Short.

A senior executive at a mobile phone technology company in the UK, who asked not to be named, confirmed the problem. "When transmitting, a phone has to radiate RF power. The laws of physics say it has to radiate in order to pick up a signal," he said.

BT Cellnet's trial used a Motorola GPRS handset to access a remote Web server over the BT Cellnet commercial network, and download Web pages to a laptop. BT Cellnet managing director Peter Erskine said a GPRS service would be launched in the first half of next year.

What are the other UK operators' plans for GPRS?

• Vodafone is testing GPRS equipment and is planning a service "some time next year".
• One 2 One is testing GPRS in conjunction with Ericsson and will launch a service "well in advance of 2002", when third generation mobile will appear.
• Orange is about to launch its own high speed data service, HSCSD (high speed circuit switched data) and is planning a GPRS service by the end of 2000.