Hands on with London's first 4G service

UK Broadband has said it will start selling its 4G services next week, in its bid to become the first provider of the super-fast connectivity in the country. On Wednesday, ZDNet UK put the service through its paces ahead of the public launch, to see just what speeds it could reach.

Residents and businesses in Southwark will be able to sign up for the 4G mobile services, following a two-month limited rollout in the London borough. UK Broadband will begin offering them directly to consumers "within the next week or so", it told ZDNet UK. However, this will not be the main business focus, as the company intends mainly to supply the service on a wholesale basis to operators.

The 4G network, which is based on Time Division Long Term Evolution (TD-LTE) technology, is capable of providing download speeds of up to 120Mbps, but typically should reach 40Mbps, according to UK Broadband.

To test the speeds delivered by the service, ZDNet UK visited a Southwark hotel and took a trip around the neighbourhood.

In the picture above, the laptop on the left is connected to UK Broadband's 4G service, while the one on the right is using a Three Mi-Fi dongle with 3G.

Using the service in a stationary position, ZDNet UK saw speed-test results of around 48Mbps. By comparison, the 3G-connected laptop returned results of between 8Mbps and 10Mbps.

The subscription price for the 3.5GHz TD-LTE service will be comparable to the typical cost of a fixed-line broadband service, at around £20 to £25, a spokeswoman for UK Broadband said. It will be provided completely uncapped at launch, meaning there will be no limit on the amount that people can download, she added.

For now, the 4G services are being delivered via an in-building LTE box that looks like any home broadband router. However, Mi-Fi units that can be carried and used on the move are scheduled to arrive in September.

The router pictured is made by Huawei and has been limited to provide a maximum of around 66Mbps downstream. It can handle up to 36 devices at once, connected via Wi-Fi, according to Philip Marnick, chief technical officer at UK Broadband.

Marnick said the upstream rate — in terms of "a pure mobile play" — is consistent at around 3Mbps. However, he noted that the service could be configured differently to help provide super-fast broadband services in rural areas, to fulfil the government's Next Generation Broadband access requirements of a minimum of 5Mbps uploads.

ZDNet UK also tried out the service in a moving vehicle around Southwark, where the speed-test results returned were in the 28Mbps-38Mbps range. As a comparison, the same test using a Vodafone Mi-Fi unit saw speeds of around 4Mbps.

With Marnick (shown above), we carried out Skype calls simultaneously across UK Broadband's service and on the Vodafone network, and found the 4G call was considerably less blocky and free from lag or stuttering. In addition, we managed to stream HD video from the BBC iPlayer service while on the move.

Mobile handsets compatible with the 3.5GHz band are expected to go on sale next year. Huawei will make mobile phones compatible with the TD-LTE network, UK Broadband confirmed. Other manufacturers are also looking at providing similar hardware, but these have yet to be announced, it added.

"We're expecting those mid-next year," Marnick said. "Huawei has already put pictures up, but there are certainly others as well."

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