Five things you need to know about small cell networks
By Greg Starr
The world can’t get enough of bandwidth. Wherever we are, we all want to be contactable and have access to any information, in any format, even if we’re 30 metres underground waiting for a train. At 4site we’ve had a lot of conversations with organisations including local government bodies, large public venue landlords and other organisations who want to enable better connectivity using small cell technology.
If you’re new to small cell, it’s a remarkably powerful way to deliver more bandwidth to users, using a highly distributed radio access network. Curious to know more? Read on.
1. What small cell is, and why it matters
Mobile networks deliver voice and data coverage chiefly through 20-metre high masts which deliver a signal for several kilometres around. But that’s an imperfect solution, not only because it leaves black spots where the radio signal can’t quite reach, but also because certain parts of its catchment area will have a concentration of users – standing at a train platform, for example – all wanting lots of bandwidth at the same time. Small cell networks deliver that supplementary coverage – both to black spots, and to high-demand bandwidth areas – by using a series of smaller radio transceivers that deliver concentrated coverage precisely where it’s needed. It’s important to realise that small cell networks aren’t just a bunch of antennas; that’s something called a distributed antenna system (DAS), an older technology which has been around for some time. A small cell network is actually a collection of small base stations, all with their own radio equipment, all working in concert to send and receive voice and data for the users in the immediate 50- or 100-metre radius of the equipment. Once established, the small cell infrastructure can also be used to deliver Wi-Fi or IoT connections: an added bonus, especially in public areas.
2. Small cell networks have lots of stakeholders
So, you want to deliver targeted extra bandwidth for mobile voice and data – maybe even deliver free public Wi-Fi while you’re at it – and you’re thinking of small cell? Well, get ready to negotiate. Buy-in will be needed from local government and planning authorities, equipment vendors who make the base stations, mobile operators, infrastructure owners (the people who own or manage the “street furniture” where the equipment will be mounted), and landowners to name just a few. Buy a big packet of biscuits because it’s going to be a long meeting with lots of chat and lots of competing agendas. In reality, of course, it’s going to take more than one meeting and real patience, which is where a turnkey partner comes in: we understand all parties’ perspectives and work to come up with a solution that delivers the coverage where it’s needed while also making commercial sense for all concerned, with a design acceptable to all. For what it’s worth, 4site’s view is that the most feasible solutions are multivendor hubs, which establish small-cell infrastructure that competing mobile operators can use as a shared resource to deliver services to their own end customers.
3. A bandwidth-addicted world absolutely needs small cell
Gone are the days when people looked at the back of the telephone directory for local bus times – they’re searching from their smartphone, at the bus stop. And it’s not just that we expect connectivity everywhere, we expect high bandwidth: Netflix, YouTube and streaming music services demand it. Small cell networks are the mechanism to expand the reach of the existing mobile network, in a targeted and – interestingly – scalable, controllable way. Did you know that innovations in mobile network technology allow certain parts of the network to do what’s known as “self optimising?” That means one tiny part of the network – let’s say a 10-metre radius around a handful of high-bandwidth end-users – can automatically be “flexed” to deliver more bandwidth on the spot when it’s needed. The power and intelligence of small-cell equipment is increasing all the time, which is why a close link with equipment vendors is vital if you’re to make the most of what your small cell network can do.
4. Small cell networks demand specific, in-depth technical knowledge
It’s important to recognise that putting together a small-cell network isn’t as easy as putting up some equipment and hoping for the best. Our experience in design and build has shown that site selection, which is critically important, is all too easy to overlook if the parties involved don’t have an appreciation of the real needs of a radio network. Concrete structures stop a wireless signal dead – that’s why it’s so difficult to get indoor coverage in large buildings – while metal and glass bounce around a radio signal, posing challenges for the receiving device. And it’s not just the environmental materials that need to be considered: when it comes to designing small cell networks, specifically when it comes to site selection, services to the potential site must be considered. Each mini radio base station is going to need electrical power, as well as fibre connectivity into a transmission network provider, like BT or eir. Discovering too late that roads need to be dug in order to deliver electricity to a favoured base station site can be an expensive mistake that plays havoc with deployment budgets.
5. Small cell isn’t just for local authorities
Many of the first small cell deployments we’ve seen have been on behalf of local authorities and city councils who want to enhance connectivity – specifically free public Wi-Fi – in order to boost tourism-appeal. But many of the conversations we’re having now are outside this particular small-cell sweet spot, and include bodies like university campuses or transport networks, who need to meet the extremely high and concentrated bandwidth demands of their end-users. New figures from Cisco reveal that mobile data traffic has grown 4000-fold over the past decade; in a single year, 2015, a stunning half a billion mobile devices and connections were added to global networks. Bandwidth-hungry mobile video traffic accounted for 55% of all mobile data traffic last year: proof, if it were needed, that our global appetite for bandwidth really is insatiable.
For large public venues, local authorities, enterprises, universities – any organisation needing to meet bandwidth demands – small cell networks are absolutely a technology to consider. While the core mast sites that power mobile networks are vital, they are only the highways of connectivity, with small cell networks providing the essential “last-mile” of the wireless network, the rural and secondary routes that deliver mobile voice and data connectivity exactly where it’s needed.
But it’s important to proceed with caution, not forgetting the complex consultation, engagement and multilateral buy-in needed to make the vision of a highly connected, high-bandwidth area a reality. With the right approach, a small-cell solution can be struck that suits all parties.