Networks head says vendor selection ongoing, though NSN is "Plan A"
Finnish operator Elisa expects to be re-using its 1800MHz spectrum for LTE by 2012, according to its head of Access Networks, Dr Eetu Prieur.
The operator recently won a licence at 2.6GHz, but also holds permission from the regulator to use 1800MHz for LTE. Prieur said that LTE at 1800MHz would double the 5.8km2 coverage per site that could be achieved at 2.6GHz, and also allow the operator to reuse its existing antenna lines. 1800MHz is also easier to re-farm than 900MHz, he said, as there are more frequencies in the band and less GSM traffic.
Elisa would also be able to re-use the site plans they have for GSM1800 and UMTS2100 services, he said, meaning sites and masts could be reused.
The only delay would be brought about by the lack of devices that have 1800MHz capability, he added. But he expects 1800MHz devices to be available 6-12 months behind other modes, which he regarded as not a big hurdle.
As for vendors, Nokia Siemens Networks has the existing contract providing Elisa's pilot network, but the operator is carrying out vendor selection right now for LTE, Prieur said. "Nokia Siemens has the existing contract," he said, "but that could change. Vendor selection is still ongoing."
With the principal advantage of 1800MHz LTE being coverage, what about capacity – does Prieur see a role for small cells, or femtocells, in LTE?
“I think operators will squeeze the macro network and ony then go to more expensive solutions like using small cells. Adding a small cell means you need fibre to go to the femtocell for backhaul,” he said.
Nor does Prieur appear to think that voice over LTE is any kind of issue to be worrying about soon. "We're completely satisfied that data is on LTE and voice on 3G. Dropping back to 3G for voice, that's fine. It’s probably not going to be fine for ever but it seems too early for us to think about that [VoLTE],” he added.
Prieur also appeared to pour cold water on one plank of Nokia Siemens' marketing around LTE.
Speaking at an event to demo LTE technology in London, Christian Fredrikson, head of sales for Network Systems, NSN, had said that the vendor has 20,000 LTE-ready Flexi base stations installed with customers. This would enable those customers to switch from WCMDA radio to LTE, merely by a software upgrade.
“We are the only ones who can do a complete software swap from W-CDMA to LTE in under 20 minutes,” Fredrikson said.
But Prieur said that the ability to move to LTE through a software upgrade would be extremely rare. “I regard LTE as a hardware upgrade,” he said, “because it is a new radio module. That is normal.”
But what of NSN’s vision of having Flexi nodes in the network, just ready and waiting to be switched over to LTE?
Prieur's view is that to be able to move to LTE, an operator will need to have the “latest” base stations as well as be able to re-use the same frequency bands they are using for their 3G or 2G services. That will be a very small selection of operators, he said.
“If you have a brand new GSM base station at 1800MHz then you could upgrade to LTE that way if you have the ability to re-use that spectrum. But usually that’s not going to happen,” he said.
Prieur also punctured some orthodoxy around mobile data demand, saying that in Elisa’s experience it has been linear, rather than exponential. Elisa has seen a steady volume of mobile data per user, at around 1.9Gb per user per month, with growth in data volumes mainly driven by new users moving to 3G, rather than an explosion of data volume per user. Currently, over half of Elisa’s customers are 2G users, so there is plenty of scope for increasing data use by migrating data users, he said.
Very heavy users could be moved to LTE, he said. That would also extend the life of Elisa’s HSPA network by offloading those intensive users off that network, he added.