Andy Sutton, Principal Network Architect, EE is speaking on the Mobile Backhaul track on Day One of the LTE World Summit, taking place on the 24th-26th June 2013, at the Amsterdam RAI, Netherlands.
Andy Sutton, Principal Network Architect, EE is speaking on the Mobile Backhaul track on Day One of the LTE World Summit, taking place on the 24th-26th June 2013, at the Amsterdam RAI, Netherlands. EE was the first to launch a national LTE network in the UK and ahead of the show we spoke to him about its progress on rolling out its LTE network and found out more about its approach to backhaul.
A year ago the prospect for LTE in the UK looked bleak. The UK operators were mired in wrangling over the proposed LTE spectrum auctions, and the only individuals gaining much from the process were the lawyers.
However, in mid-2012 EE managed to pull off something of a master-stroke when UK regulator Ofcom allowed it to re-farm its 1800MHz spectrum. It has a surplus of this following the creation of Everything Everywhere through the merger of T-Mobile UK and Orange, owned by parent company’s Deutsche Telekom and France Telecom.
The move set the cat amongst the pigeons in the UK telecoms markets but in late October 2012, under the new EE brand, the UK’s first LTE network was switched on across 11 cities, in a project in which EE will invest more than £1.5 billion pounds.
At the time of writing, LTE covers 45 per cent of the UK population, and this is scheduled to hit over 55 per cent by the summer and 70 per cent by the end of 2013. The eventual target is 98 per cent LTE population coverage by the end of 2014.
The project wasn’t just about LTE though, Andy Sutton, Principal Network Architect at EE told Telecoms.com in a recent catch-up. “It was also about enhancing the 2G layer and improving the 3G network with Dual Carrier HSPA”, he said.
DC-HSPA currently covers 40 per cent of EE’s network, an important factor in keeping customer satisfaction high where LTE hasn’t yet arrived. While DC-HSPA can’t match LTE for consistent double-digit speeds, and doesn’t offer the same low latency or upload speeds, it is capable of matching it in ideal circumstance for real-world speeds to the handset on the downlink, and delivers a great mobile data experience.
In terms of network architecture, the LTE and DC-HSPA upgrades are separate. The DC-HSPA upgrades use EE’s spectrum, but employ the infrastructure that it shares with Hutchison as part of the shared network MBNL deal between T-Mobile and Hutchison, that predated the EE merger. Its 2G and LTE use its Huawei SingleRAN technology, and Sutton explains that its LTE upgrades are not available to others using that shared infrastructure.
“It’s a unilateral RAN deployment but it uses all of the commonalities and synergies afforded by MBNL. So we use the same sites, structures, cabins and power and we share the backhaul between 2G, 3G and LTE. But it’s not a shared LTE network in the way we had a shared 3G network. And that’s a very important point as we’re investing quite heavily in deploying that LTE infrastructure to give EE a benefit in the marketplace.”
For backhaul EE uses Gigabit Ethernet, having moved away from using TDM and ATM during the Godiva project that integrated the networks of T-Mobile UK and Three. From 2008 onwards MBNL implemented a backhaul upgrade programme to deliver backhaul running at 100Mbps, this was sufficient to support 3G and was based on BT MEAS (Mobile Ethernet Access Service), and hybrid point-to-point microwave radio. But to keep pace, or ahead of the demand curve, improvements are being made.
“As we roll out LTE, we upgraded from Fast Ethernet to Gigabit Ethernet and we’re continuing with an evolved version of the BT MEAS product. We’re also introducing Virgin Media backhaul.” The latter is additional to EE’s backhaul agreements with UK incumbent BT.
What’s interesting about EE backhaul is that while its 2G/4G and 3G are separate, the backhaul for all of them is aggregated, and runs over the same network with logical separation used to control the traffic flows within the pipe. Sutton explains the reasoning behind this.
“It allows us to realise synergies and makes for a more efficient network design. It helps as we only have to connect to a particular location once and then we can actually use that capacity effectively to support multiple radio access technologies. As we move towards SingleRAN, ultimately we have a single interface. It’s much more efficient, much slicker, more reliable and easier to manage.”
As well as Ethernet for Backhaul EE also offers its customers wifi access through BT Openzone hotspots widely found in public locations throughout the UK, of which there are around 3,500. Additionally, through its agreement with Virgin Media, EE customers also get wifi access for free at London Underground stations.
Sutton says EE views wifi as an integral part of its appeal. “We are looking to incorporate wifi as part of the story,” he says. However, he points out that wifi doesn’t always offer the best customer experience. “Currently with wider radio channels those using LTE have a better experience than those using public wifi. What we don’t want is a device selecting wifi when actually the experience on cellular would be better.” Sutton said that eventually the network will be able to intelligently decide which is the best connection for the user, a feature that he points out has been part of the 3GPP standards since Release 5 in 2002, along with IMS, both of which the telecoms industry is only now starting to embrace.
In terms of other innovations Sutton says EE is looking at small cells but that it is currently working out exactly how and where they will be required. Currently EE is focused on putting capacity in to the macro network and that LTE would push back the need for small cells. “The problem is how we see traffic migrating between the two.” The long-term aim is to create a HetNet, with a mixture of macro cell and small cells working intelligently together. However this will require the use of LTE small cells. “3G small cells will be for specific hot-spots, but we won’t be rolling them out to large areas. 3G wasn’t really designed for HetNets whereas LTE was, so in the future we’ll be deploying a large number of LTE small cells as we really look to add capacity in a particular geography.”
Deploying HetNets will inevitably have an impact on how backhaul is set up Sutton says. “One of the challenges of deploying any small cell technology is that you have to ensure that you have the correct backhaul solution in place. Increasingly, the coordination and cooperation of the two layers (macro and small cell) will allow you to get greater capacity and greater performance. Those are quite clear objectives for us as we manage the on-going quality of experience.
Speaking to Sutton, the quest to improve the quality of experience is an overriding theme and he says that he is excited about the progress that EE will make in 2013. “It’s very exciting. Getting [LTE] out to as large a population as possible is our objective.”
It’s also going to get better for those that have already signed up he claims. “In-building coverage will improve. Capacity will improve. At the moment we want to get LTE services out there so people can see what it can do. It’s a game changing technology. It’s a real step forward.”
The LTE World Summit, the premier 4G event for the telecoms industry, is taking place on the 24th-26th June 2013, at the Amsterdam RAI, Netherlands. Click here to download a brochure for the event.