8 AUGUST 2019

Many customers, colleagues and friends are talking about the planned roll-out of 5G networks and services, wondering what it will mean to the average consumer of mobile services.  In terms of how Gartner’s hype cycle measures these things, I think it’s fair to say 5G has reached the “Peak of Inflated Expectations”.  That’s because there’s currently a lot more focus on the cool use cases that 5G is expected to enable, such as Autonomous Vehicles, Augmented Reality (AR) and the ubiquitous Internet of Things (IoT).  But in reality, 5G is not a single technology, innovation or solution.  It’s actually an umbrella term for the next generation of mobile network technologies, some of which are already quite mature and deployed on existing 4G networks.  In fact, 4G/LTE networks will exist alongside 5G for the foreseeable future – because in most cases, 4G is doing just fine for how subscribers use their phones today and will continue to evolve in its own right.  For example, Narrowband IoT (NB-IoT) is a low power, wide area network (LPWAN) that relies on LTE-Advanced technology. It provides a pathway to 5G IoT and offers many comparable benefits, like low power usage, long battery life and low device cost.

While 4G coverage will continue in most markets, carriers have been preparing for 5G because it does offer significant benefits – including speeds up to 100 times faster than 4G. But this transition comes with a unique set of hurdles, requiring many changes within a wireless network – especially to the Radio Access Network (RAN) and the Core Network:

RAN Challenges:

  • 5G New Radio (5GNR) introduces new spectrum and interference issues, while simultaneously needing to co-exist with 4G, 3G and even 2G.
  • RAN subsystem architectures are becoming much more complex, through Cloud RAN (cRAN), Virtual RAN (vRAN) and Extensible RAN (xRAN)
  • Shared ownership of RAN elements between operators is becoming more common through Multi-Operator RAN (MORAN) and Multi-Operator Core Network (MOCN)

Core Network Challenges:

– 5G introduces new core elements (e.g. User Plane Function UPF) and a new core architecture
– Control and User Plane Separation (CUPS), which already exists in some virtualized 4G networks, is now a standard part of the new 5G core architecture
–  Network slicing will be common, where multiple virtual network instances exist using a shared physical infrastructure, supporting differing service types on each

As 5G networks begin to launch, many of these challenges have been addressed.  For carriers, the next hurdle is assuring customers are getting the right quality of experience. This becomes especially challenging with 5G, given all the new services, devices and expanding ecosystem of partners involved.  Maintaining customer quality of experience (QoE) will be critical for the commercial success of 5G, but the additional complexity of the new Core and RAN networks makes it more difficult and costly to measure.  On its own, this might not be such a problem, however 5G technologies will inevitably introduce associated QoE issues, especially in some key areas:

Increased inter-cell interference, caused by a very dynamic, mixed population of heterogeneous cells.  5G networks consist of many more cells of many different sizes, compared to 4G networks.  This is known as a HetNet (heterogeneous network), where Femtocells, Picocells and Microcells are mixed in amongst the more traditional Macro cells to provide improved coverage in dense urban or indoor areas. These cells are needed to provide the coverage some 5G spectrum requires, but they can overlap and cause interference when not managed properly.

Unpredictable coverage and dynamic performance within each cell, due to the more complex RF designs inherent in 5G NR, such as Multiple Input Multiple Output (MIMO).  Understanding and predicting the coverage of each cell is now much more difficult, as coverage now depends on the behavior and location of all other devices in the same cell

Poor throughout and latency due to congestion at popular locations.  Subscriber expectations will be high for 5G, so the “acceptable” thresholds for throughput and latency will be correspondingly higher than those used for 4G. And 5G’s dependence on small cells means it will take time to optimize their placement.   Cast your mind back to when you watched low-res music videos using an original iPhone on a 3G network in 2007; what was once deemed “acceptable” throughput and latency is soon to be perceived as “poor.”

Cell capacity (in terms of the numbers of simultaneously connected devices) will be severely challenged when large populations of IoT devices are commissioned.  Each cell has a limited set of RAN resources to allocate towards signaling, and large numbers of IoT devices will need to share these scarce resources with all the other devices served by the same cell.

In summary, for mobile network operators, 5G technologies present many new challenges for deploying and managing the network – many of which are driven by increased customer demands and expectations.  Service demands on the network will increase significantly, with IoT bringing many more simultaneously connected devices and subscriptions.  The capacity expectations of subscribers will similarly increase in terms of peak/average bandwidth, lower latency requirements of some services, and improved coverage.

It’s true that 5G brings many benefits to consumers and industry, with support for new services and applications, and substantial improvements from 4G.  However, these benefits come at the cost of increased complexity for the network operator, and significant QoE challenges.  Carriers need to be prepared to identify and address these at the outset. After all – first impressions matter, and consumer expectations for 5G are high, to say the least.

A QoE “perfect storm” is brewing, and mobile operators are going to find it much more difficult – and expensive – to measure the Quality of Experience due to the increased complexities of the 5G network. Will you be ready?  TEOCO can support you with the 5G challenge.