LTE in South Africa: Construction issues outstrip technology considerations

Although some operators are still deploying LTE networks for coverage purposes, many are now trying to differentiate themselves though speed, services and QoS. Previously the key differentiator was coverage, but we have moved into an era of who can provide the highest speed. Therefore, construction becomes important, as the race is now whoever deploys first is the one who can claim higher bandwidth.

some operators are still deploying LTE networks for coverage purposes, many are now trying to differentiate themselves though speed, services and QoS (image: file)

Consider the bold steps South Africa took for 2010 by committing to and ensuring that Africa’s first FIFA World Cup was a resounding success.

The project, which had tight immovable deadlines, required exceptional planning in order to achieve the required results. Among other things, the project meant:

· New stadiums needed to be built and existing ones upgraded (five new stadiums were built and five existing ones were upgraded). More than 70,000 construction workers joined together to ensure the construction was completed on time

· Public transport infrastructure needed to be upgraded—major road networks were improved, repaired and a new rapid rail system, “Gautrain,” was installed in Johannesburg

· Broadcasting and telecommunications infrastructure had to become world-class, with multiple protection and fail-over options and vastly increased bandwidth

· Airports had to meet world-class standards

Preparations costs for the World Cup went over R27bn (US$3.9 billion), and South Africa hosted more than 300,000 tourists during the event.

The slogan that was used by South Africans during the preparations of the World Cup was a theme phrase: “Ke Nako,” which means, “it is time.” This promoted the idea that South Africa—and Africa as a whole—was ready and capable of hosting huge global events. Again, we can say “Ke Nako” for South Africa to implement LTE, too—not only to equal world-class telecommunications infrastructures but also to bring to South Africans all the benefits that LTE systems enable as well as bridge the Digital Divide.

Like the World Cup stadium challenge of the 2000s, building out a national LTE infrastructure in South Africa is a major undertaking. The largest challenges in building out an LTE network consist of planning, staging and deploying the technology at maximum speed and with minimal costs. Mobile operators are in a tight race to build out LTE networks in South Africa as quickly and cost-effectively as possible; backhaul is the critical component.

There are more than 200,000 2G/3G cell sites in South Africa; LTE penetration is only just starting. Mobile operators want to have 80 percent of their subscribers covered by LTE as of 2015, so a massive construction project lies ahead with a tight timeframe for completion.

To give this some perspective, we will revisit the World Cup analogy: Building networks to support LTE is similar to the concerted, six-year effort to buildout the stadiums and associated infrastructure for the 2010 World Cup. But it was not the compressed timeframe that was daunting; it was the number of stadiums and amount of infrastructure that needed to be built in that timeframe. Similarly, network buildout to support LTE is not about the capacity needs of backhaul—both microwave and fibre exceed the capacity requirement—but rather the massive construction that is both urgent (speed of deployment) and expensive (cost of build).

Backhaul is the significant factor in accomplishing LTE rollouts. Mobile operators can simply overlay LTE base stations on their existing cell site infrastructure to handle the Radio Access Network (RAN) portion of the deployment, but backhaul in most cases will require switching from copper to either fibre or microwave because of the capacity required.

Microwave and fibre have ample capacity to handle LTE backhaul. It is estimated that 200 Mbps will be required to backhaul 3G and LTE services over the same link. Microwave and fibre provide this level of capacity. The backhaul must also provide QoS capabilities to discriminate between applications and to deliver the right level of service to each application.

The issues are deploying LTE backhaul quickly and with minimal capital expenditure. And operational expenditures are proportional to capacity. Because LTE has two to five times more capacity than 3G, operational costs should at least double, in line with the increased capacity offering of LTE. 2G and 3G networks are not going away either. Therefore, it is essential to hold down backhaul costs.

Fibre is as a good choice in fibre-rich environments because of its ease of deployment due to pre-existing installations—the story is different where fibre does not pre-exist. In greenfield urban environments, microwave maintains its superiority over fibre for quicker time-to-market and more cost-effective implementation.

In suburban and rural areas (e.g., most parts of South Africa, the rest of Africa), microwave is an even better fit than fibre because it is even easier and much more cost-effective to deploy in the long run over the longer distances involved between cell sites as it can take months to run fibre to distant cell sites.

Another requirement is the ability to carry 2G, 3G and 4G traffic on the same backhaul link. 2G networks run TDM traffic rather than IP, so the microwave solutions must therefore use hybrid radios that can carry both TDM and IP.

From a deployment standpoint, microwave radios require site surveys and engineering, path planning, and installation. It is therefore essential for mobile operators to work with a technology provider who has strong experience in deploying microwave for cellular backhaul.

Rolling out LTE will require deploying new backhaul to tens of thousands of cell sites, all within a tight timeframe and budget. When fibre is not readily available, microwave technology is the best choice for backhaul technology. But in seeking a solution to the backhaul problem, mobile operators should look for microwave technology vendors who have extensive experience in successfully deploying their products in telecommunications networks. If microwave technology helps to address the cost issues of LTE backhaul, an experienced microwave vendor will solve the logistical issues in getting it deployed.

Siphiwe Nelwamondo, Technical Marketing Manager, Aviat Networks