The lack of fibre-optic transmission networks outside SA’s main urban centres could prove a huge stumbling block to rolling out next-generation long-term evolution (LTE) networks in rural areas and add significant costs for operators wanting to meet roll-out obligations for these networks.

Richard Morse, group technology executive at Dimension Data subsidiary Plessey, says there is a desperate need for more fibre infrastructure in rural areas because microwave technology is simply not good enough to support the sorts of speeds and latencies that consumers will demand from LTE networks, which will eventually offer download speeds in excess of 1Gbit/s.

“When you start thinking about how you’re going to get that data back from multiple towers to a central location, you realise that new [fibre] infrastructure has to be built,” Morse says.

In large parts of SA, even in densely populated rural areas like the outlying areas of KwaZulu-Natal, there is very little fibre in the ground to provide backhaul to next-generation radio access networks, he adds. And it’s simply too expensive for one operator to absorb the cost of building this network, which Morse estimates could cost more than US$10bn (R75bn).

Government, through the Independent Communications Authority of SA (Icasa), wants companies that are successful in bidding for spectrum that is suitable for building LTE networks in rural areas to provide 70% geographic coverage, but without fibre to connect the radio access network operators won’t be able to offer the speeds consumers will get in urban areas.

“The objective is to have high-speed broadband in rural areas and that means the same infrastructure in urban areas has to be deployed in rural areas,” he says. But international research shows that as much as 70% of the network costs for new operators are in establishing backhaul links. “There’s a reason why the current operators don’t have fast 3G services all over the rural areas and that’s because the backhaul infrastructure isn’t there to support it.”

Though the incumbent operators make extensive use of microwave technology for backhaul, especially in more remote parts of the country, it’s simply not suited to next-generation wireless broadband networks, he adds. Microwave should only be used to connect onto fibre backhaul as quickly as possible as more than one or two “hops” between microwave transmission towers means network latency becomes too high. Microwave is also affected by adverse weather conditions.

One solution to the problem is infrastructure sharing, Morse says, where components of the network, including the active radio access segments, are pooled by multiple players to reduce costs.

He believes there is scope for companies with access to spectrum suitable to LTE — including Sentech, Neotel and iBurst parent Wireless Business Solutions — to work with successful new spectrum licensees and pool their resources to build a national LTE network.

“The concept of radio access network sharing is an essential part of the planning of any prospective market entrant,” Morse says. “Plessey has been putting the R&D into laying the groundwork to enable that sort of sharing in reality.” — Duncan McLeod, TechCentral