This year has been predicted to be the year of the small cell, which should come as no surprise – there have been similar predictions for several years.
There are, however, indications that 2015 will be different and the prediction may be accurate. The end of 2014 saw several announcements by small cell providers working with vendors on outdoor deployments. Research firm ABI Research predicts the number of LTE small cells will double in 2015. Operators are also commencing their research and development around “5G,” which is likely to use the same macrocells as previous generations, supplemented by small cells to “fill in” the network.
Small cells already outnumber macrocells – in fact, they outnumbered macrocells back in 2012. But, 80% of these cells are residential microcells that are not planned and placed by operators to create a better network, but rather are instead used by consumers to get better coverage at home. In reality, the use of small cells by operators to deal with congested networks is still barely past the trial stage.
No easy task
There’s a good reason for this: it’s far from easy. Small cell deployments are often fine in principle, but are fraught with practical problems. Backhaul infrastructure is a major consideration – ensuring that adequate backhaul is available to support a small cell rollout is often the biggest challenge for an operator.
Access for maintenance is another challenge for operators to consider. Lampposts are often described as the perfect place to locate a small cell, but if something goes wrong it can be very difficult for the operator’s engineers to reach and fix the small cell quickly if its location is especially busy or inaccessible. For example, if a small cell in central London malfunctions during the day, engineers might only be able to reach and repair it early the next morning, and then only for a single hour.
It’s not only about offload
The deployment of small cells is about more than simply offloading data use where the network is busiest. There are subtle, but significant, and not immediately apparent factors that influence operators’ decisions on their small cell placement.
For example, the presence of a number of particularly data-hungry users at the edge of a macrocell will affect the quality of service for anyone else using the same cell. The problem in this scenario is not the volume of users, but rather the location of the users. If this scenario is repeated often – for example, if the high-data user is at work or at home – users will find their experience degraded regularly; a small cell could be the solution.
Other variables
This is just a single example and doesn’t take into consideration the other variables that may affect the planning of a small cell roll out in a given area, such as the different devices used by subscribers, the proportion of 3G to 4G users and the availability of Wi-Fi offload nearby. With these factors in mind, simulation of how data usage may change in the future across the network combined with accurate geolocation, are vital to ensure that any rollout is going to be cost-efficient for the operator.
Selective, targeted small cell rollouts – particularly indoors, where usage is highest – can certainly ease congestion and relieve bottlenecks and pressure points on the network. However, traffic hot spots are not the only data that operators should draw upon when planning their small cell roll out.
Know your network users better
Of equal importance is knowing which customers are using the network. While operators can use geolocated data to create accurate maps that identify traffic hot spots, these maps only tell one part of the story. They show network usage without providing visibility on the subscribers using it, such as who they are, what tariff they’re on and how much revenue they generate for the operator.
Any investment into the network must be supported by a guaranteed return, and to do this operators need to incorporate billing data into their network planning. As an example, compare two areas of high data use in different parts of the city. They might initially appear similar, with users in both areas using data in a way that creates bottlenecks and affects other subscribers using the same cell.
A closer analysis
However, a closer analysis that incorporates customer billing data reveals that one area contains the office of a high-value business account, in which the operator provides devices to dozens of staff members. When all together in the same place, these workers – and their connected devices – cause the network to become very congested.
In contrast, the other area of high data usage in the city is a university campus that includes student halls of residence. The high usage comes from data-hungry students on all-you-can-eat tariffs that cover everything from mobile broadband and media streaming to over-the-top applications and services.
If only data traffic is considered, both areas are candidates for small cell rollout as a means to maintain network performance. But the value of these different customer groups – specifically, the potential return on investment for the operator from the corporate customer vs. the student subscribers, based on their respective data tariffs – will be significantly different.
Profitable planning
Identifying these types of cases is impossible on any scale without automation. To be effective, billing data combined with operators’ own potential ROI targets need to be part of the small cell planning process right from the start.
Importantly, by introducing subscriber and billing data into their small cell planning, operators can more accurately identify where they need to locate their small cells in a way that can ensure services can be delivered to subscribers who are paying for access. It’s an important new development that enables operators to make the most of small cell investment, making them less of a simple “sticking plaster” that fixes an overloaded network and more of a targeted solution that improves network performance for those customers who most expect it.
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