I've recently focused on the critical enablers of wireless evolution, as we go towards 5G, IoT, gigabit WiFi and other technologies, especially in the enterprise.

As well as spectrum - which I've covered extensively in recent months - deploying in-building coverage is going to be another issue. This often gets overlooked by mobile strategists and policy-makers, despite its importance.

It is not a new assertion that indoor networks are important for enterprise. The frustrations of poor indoor cellular coverage are universal, while businesses of all types need to provide employees and guests with high-quality Wi-Fi.

Yet there is a risk that future in-building wireless gets worse, not better. Three sets of challenges lie ahead:

• New technologies and frequency bands, especially for 5G & WiFi at higher frequencies, where signals don't go through walls well. Other wireless standards will be important for indoor use as well.
   
• New use-cases and behaviour. IoT will use indoor wireless in places and fashions that humans don't. Some may be safety-critical, too.
   
• New service provider types will need access to indoor coverage systems, as well as traditional MNOs.

(If you don't want to read the full post, I'll be presenting on a client webinar on October 5th - details here. I'll also cover trends in home Wi-Fi in a later post, while I've already written about industrial facilities in a number of previous ones, such as here, as the issues are as much about spectrum as about infrastructure and planning.)

Various solutions abound for providing good signal indoors – distributed antenna systems (DAS), small cells, or even just deployment of lower-frequency bands in outdoor networks, with better penetration through walls. Yet costs remain considerable, especially as usage increases near-exponentially. Upgrading or retro-fitting existing installations often requires hard economic decisions, given that most such investments are not directly “monetised”. Suitable expertise, foresight, planning tools and ongoing monitoring/reporting are important.

The future, however, will accelerate the role of in-building/on-site wireless connectivity – in both predictable and unpredictable fashion. If we consider what a building might look like in the year 2030, say – and how it may be used and occupied – we can start to see the challenges and opportunities.

As well as today’s well-known and well-described uses of wireless (smartphones and laptops on Wi-Fi and cellular networks), we can expect to see a huge number of new uses emerge. This means that today’s implementations will require future-proofing, to support the unknowns of tomorrow. For example, consider the implications of: 

• IoT deployments for smart buildings, such as a proliferation of sensors for heating, security, or the operation of elevators. These may require better coverage in unusual places – in ceiling voids, lift-shafts, basements and so on. Bandwidth and latency requirements will vary hugely, from life-critical but low-data fire/carbon monoxide sensors, to networked video cameras, or once-an-hour reporting from water tanks.

• Moving devices such as robots or automated trolleys, delivering products around the building. While some will be fully-autonomous, others will need constant wireless connectivity and control.

• 5G networks will be deployed from around 2020, with further evolutions in following years. These may be extremely demanding on in-building coverage solutions, especially as some networks are likely to use frequencies above 6GHz – perhaps even as high as 80GHz. Extensive use of MIMO and beam-forming may also add complexity to indoor implementations. (A new variant of WiFi known as WiGig also uses 60GHz frequencies)

• Likely huge growth in narrowband wireless, connecting low-powered (but maybe very dense) networks of sensors or other endpoints. These may use 3GPP technologies such as NB-IoT, or other options such as LoRa and SigFox.

All of these trends imply very different traffic patterns. It is not realistic just to extrapolate from current usage – robots may go to places in buildings where humans do not, for example. Mobility requirements may evolve – and so will regulations.

It is not just new classes of device and application which will need to be supported by well-designed coverage infrastructure, but also new classes of service provider that need to access them.

• The advent of new unlicensed or shared-spectrum models of frequency allocation (eg CBRS in the US, or MuLTEfire) may mean the arrival of new operator types – dedicated IoT solutions providers that “bring their own wireless”; enterprises acting as their own local on-site MNOs; various models of “neutral host” and so on.

• Private enterprise cellular networks are starting to become more widespread. Some governments are allocating spectrum for industries like utilities or smart-cities, while equipment vendors are offering optimised enterprise-grade cellular infrastructure.

• Potential future regulations for emergency-services wireless connections. Police and fire authorities are increasingly using broadband mobile, both for humans and remote-sensing devices.
   
• Distributed-mesh service providers, that operate as decentralised networks with micropayments, or as community initiatives. Some may use blockchain-type arrangements for shared-ownership or membership fees.

One of the unknowns is about the convergence (or divergence) of different network types. On one hand, cellular networks are embracing Wi-Fi for offload, or for multi-network aggregation, especially as they worry that returning flat-rate data plans may stress their networks. On the other, some networks are looking at running 4G/5G in unlicensed spectrum instead of (or in addition to) Wi-Fi. Yet more service providers are adopting a “Wi-Fi first” approach, reverting to MVNO models for cellular where needed. Future permutations will likely be more complex still. All will (ideally) need to be well-suppported by indoor wireless infrastructure.

For property developers and owners, the quality of indoor networks is increasingly key in determining valuations and rental occupancy. Already seen in hotels, and office new builds, it will be important for today’s new constructions and refurbishments to support adequate flexibility and headroom for the next decade or more.

This takes on further emphasis if you consider the trend towards “buildings-as-a-service”, exemplified by organisations such as WeWork. These new classes of facility often incorporate wireless connectivity both as a billable service element, but also to enable their owners to manage the properties effectively, in terms of energy-efficiency and security. Other forms of monetisation and data-analytics around wireless location-sensing/tracking are also becoming more important.

Lastly, in-building challenges will be driven by the specific location and industry, which themselves may change in nature over the next decade. New building materials, construction practices and regulations will impact wireless in unpredictable ways – more metallic insulation perhaps, but also perhaps robot or pre-fabricated construction allowing wireless systems to be installed more easily. Individual industry verticals will have their own shifts – what will retail stores look like, and how will customers behave, in the era of home deliveries by drone, but more on-premise “experiences”, perhaps with AR/VR systems? What workplaces of the future look like, in an era of self-driving vehicles? Industrial facilities will become increasingly automated, with the largest uses of wireless connections being machines rather than humans. Hotels and airports will see shifts in data connectivity needs from employees and visitors, as application usage shifts.

Small cells look certain to play a more important role in future, and Wi-Fi is going to remain the most important indoor technology for many users and businesses (ignore the fantasists who think it's at risk from 4G / 5G - see my earlier post here).

There are no easy answers here – even if you construct good scenarios for the future, undoubtedly we will be surprised by events. But some form of upfront discipline in designing and building indoor wireless solutions is ever more critical, given the unknowns. The more future-proofing is possible, the lower the potential risk of being caught out.