Exploring how traffic patterns drive network evolution

Mobile networks must continuously evolve within the RAN domain, utilizing mid-band and mmWave to meet capacity and speed demands, but not all locations are equal. This is highlighted by a detailed analysis of data traffic growth and patterns across different locations in some North American and European networks, providing key insights and considerations for network evolution.

Traffic growth is not universal across locations

Variations in subscriber concentrations are clearly illustrated when traffic growth in several networks from Western Europe and North America are analyzed across different location types: dense urban, urban, suburban and rural areas. Traffic demand per location is 500 to 1,000 times higher in dense urban locations relative to more sparsely populated rural locations in both Western Europe and North America.

In Western Europe, relative growth in traffic during peak periods across the four different locations between 2021 and 2022 can be seen in Figure 23. Data for the most recent year shows that traffic growth per location is highest in dense urban and urban locations, with up to 80 percent growth.

But it has been much lower in rural areas with growth below 10 percent. The proportion of traffic on 5G in rural areas is lower due to reduced population coverage at the current stage of network deployment and also likely lower penetration of 5G devices.

When comparing North America with Western Europe, there are a couple of key differences that can be observed in the 2022 traffic. Firstly, traffic demand is higher in North America in both dense urban and urban locations. Secondly, in all locations, a greater proportion of traffic comes from 5G, which is likely a driving factor behind higher traffic volume in urban areas.

Traffic behavior drives different needs across locations

To support network evolution strategies, it is important to understand traffic patterns and behavior in more detail in different locations. Understanding daytime population density is very important, especially in dense urban-to-urban areas, since the highest traffic is in the middle of the day in both Western Europe and North America. Figure 24 shows that in Western Europe, dense urban areas have the peak traffic period during the middle of the day, compared with the rural areas, which have the peak traffic period in the evening. The rural areas are likely to be impacted by Fixed Wireless Access (FWA) subscriptions which have a significantly higher usage per subscription. North America follows a similar pattern, and in both regions urban and suburban traffic has a much flatter profile with the highest traffic levels more evenly distributed between the middle of the day and the late evening before traffic drops off.

Analysis of traffic by location shows a greater proportion of total traffic is uplink in dense urban locations in the peak period compared with other locations. In North America, dense urban uplink traffic is around 14 percent of total traffic compared with rural areas, where it is around 9 percent of total traffic. Traditionally for mobile broadband and FWA services, uplink has had a smaller impact on overall user experience. However, with more uplink-centric services there is now also a need to consider uplink performance, especially in dense urban areas. This is also required to prepare for new uplink-demanding services like XR, which will place even more demanding requirements on networks.

Examination of network data across the locations shows that, although total traffic is significantly higher in urban locations, individual traffic in peak periods is highest in suburban locations, with this difference being much more pronounced in Western Europe. This shows how the combination of population density and peak usage per user is important when considering network capacity requirements.

North America leads Europe with mid-band deployments

Globally, 5G population coverage reached 35 percent at the end of 2022. However, when looking into the mid-band deployments that bring the step change in network performance, only about 25 percent of 4G sites have been upgraded, and outside China this drops to around 20 percent. There is a significant difference in the regions studied here, with North America at over 30 percent and Europe just above 10 percent.

Looking at the specific networks analyzed, 5G has been commercially deployed in Western Europe and North America since 2019, but rollout is far from complete. In Europe, some additional sites, totaling around 5–10 percent, have been added to suburban and rural areas to meet increased coverage expectations and license obligations. The focus on fulfilling coverage requirements is reflected in the much higher levels of New Radio (NR) frequency division duplex (FDD) sites deployed for coverage, compared with mid-band time division duplex (TDD) sites for capacity in the networks analyzed from Western Europe.

The 5G deployments in Western Europe and North America for the locations sampled give a snapshot of the status of network deployment in the two regions, as illustrated in Figure 25. The figure shows the proportion of sites that have been upgraded to 5G NR FDD, compared to sites where 5G carriers have been added in either the mid-band TDD or with mmWave. Depending on the capacity demands of a particular site, mid-band TDD and mmWave carriers can be co-located at the same site. In Western Europe, it is notable that while the 5G NR FDD bar is as high as North America – or higher in certain cases – much of this has been achieved through spectrum sharing. This gives a high level of coverage but without the same levels of capacity, latency, or uplink capabilities.

In North America, there has been a focus on mid-band and mmWave from the early stages of 5G deployment to deliver higher capacity alongside coverage. mmWave is capable of supporting higher capacity in the network for dense urban and urban locations. Since the data set was collected, the North American operators have continued deploying mid-band at pace, as reflected in the number of sites deployed now being higher than the global average.

Rollout is far from complete

Network deployment comprises both coverage and capacity sites. Coverage sites provide basic geographical coverage while capacity sites add extra capacity where coverage is good and there is a high density of subscribers. To achieve optimum 5G performance, both coverage and capacity must be available throughout the network. Upgrading coverage sites with 5G enables coverage to be built out, but upgrades of capacity sites are also required to realize 5G services to most subscribers. Our analysis shows that firstly there are still existing sites without 5G, which need upgrading to 5G to enhance network coverage. Secondly, there are many sites without the additional capacity dimensions, and mid-band TDD deployments, needed to deliver the step change in 5G performance. Without network evolution, resource utilization will increase, resulting in poor user experience. Therefore, peak utilization must be maintained or, ideally, reduced over time to offer higher speeds and ensure a high-quality user experience.