Analysis: How beneficial will 4G be to the UK?

It is hard to tell how much fourth-generation (4G) mobile internet could be worth to the UK's flagging economy.

But considering how quickly smartphones and other 3G-enabled mobile devices seem be flying off the shelves, it is clear that mobile operators, phone and accessory manufacturers, retailers, application developers and the people they employ represent a significant commercial ecosystem that stands to make a lot of money by encouraging businesses and consumers into upgrading current mobile handsets to support faster mobile broadband speeds.

A shame then, in difficult times, that commercial 4G services expected to offer minimum bandwidth of 5Mbit/s and average throughput of 30-50Mbit/ are still three to four years away in the UK, despite having already been rolled out in parts of mainland Europe and the US.

In contrast, the UK is still at the trial stage, with O2 having announced a London trial of the latest Long Term Evolution (LTE) 4G wireless technology this week.

The pilot will see the operator upgrade over 25 existing masts covering 15 square miles in London's Canary Wharf, Soho, Westminster, South Bank and King's Cross areas. It will run for six months, connecting up to 1,000 hand-picked users. A key aim is to find out whether peak rates of 100Mbit/s are actually achievable in dense urban environments where available bandwidth varies considerably according to the number of people connecting simultaneously and how close to the base station they happen to be, O2 head of LTE Rob Joyce told Computing.

"We learned in previous trials in Slough what a loaded network looked like, but with only 50 users we never got to test the signalling with lots of people," he said. "We think the minimum throughput for the guy standing at the cell edge will be 5Mbit/s, with closer to 100Mbit/s peak rates for those at the centre, but typical throughput will be 30-50Mbit/s."

Unlike the tests in Slough, which used 4G LTE equipment from Huawei, the London trial is based on networking infrastructure supplied by Nokia Siemens Networks (NSN), which supports up to 3,000 simultaneous connections to each cell.

"We have not been able to test it at its limit yet, and hopefully London will get close," added Joyce.

With no 4G handsets as yet available, O2's trial will connect 4G dongles for laptops and other devices with USB ports – not ideal for testing a network that will eventually carry traffic from mobile phones due to significant differences in location and application usage behaviour but still better than nothing, according to Saverio Romeo, senior industry analyst at research firm Frost & Sullivan.

"A trial done on laptops, netbooks or laptops will not give you a lot of insight into mobility aspects but it is important that a mobile operator has started a trial in highly dense user environments because that is where the big challenge is," he said.

The big question is how many people will actually need that sort of bandwidth to push data onto a small screen, mobile device where HTML traffic has been optimised to work better over slow connections.