According to the Global Mobile Suppliers Association (GSA), 480 operators had commercially laun­ched 4G long term evolution (LTE) networks across 157 countries as of end-January 2016. In addition, the number of LTE subscriptions had reached around 1.07 billion at the end of 2015, representing a year-on-year growth of 107 per cent. Meanwhile, LTE subscriptions now account for 14.55 per cent of the global mobile base.

With over 580 million LTE subscriptions, the Asia-Pacific region has the highest share (54.3 per cent) in the total number of LTE subscribers. North America is the second-largest LTE market, with around 237 million LTE subscribers and a share of 22.2 per cent. Meanwhile, Europe accounts for 14.8 per cent. However, there are wide variations in global 4G network deployments in terms of spectrum bands, speed, coverage, etc.

tele.net takes a look at the differences in network speed and coverage across countries, the spectrum scenarios in global LTE deployments, the availability of an LTE ecosystem and the challenges invol­ved in LTE deployment…

Wide variations in speed and coverage

A report on the state of LTE released by OpenSignal in September 2015 finds that while LTE has become a near-ubiquitous technology in some countries with high broadband speeds in every pocket, it is still at an infancy stage in others, with wide variations in coverage and speeds at different locations. As per the report, operators based in South Korea have the best LTE networks overall, with download speeds of over 25 Mbps and comprehensive 4G coverage. Meanwhile, US-based operators offer below average speeds but decent coverage, while operators in Japan provide excellent coverage with average speeds. The poorest performers in terms of network and coverage tend to be in the developing regions of the world and in some European countries.

In terms of the proportion of time that users have access to LTE signals, South Ko­r­ea is the leader, with its customers be­ing able to connect to LTE 97 per cent of the time. XL Axiata in Indonesia posted the lo­west coverage score, with consumers getting LTE signals only 19 per cent of the time.

The report further observes that LTE network speeds have begun to increase in many countries. In South Korea, they nearly doubled in 2015 in comparison with 2014. This can be attributed to the fact that many operators are deploying new LTE systems in new frequency bands, adding more capacity to their networks and enabling more customers to be served without sacrificing performance. Several operators are also deploying LTE-advan­ced technologies to boost speed. Mean­while, some countries that had been the earliest adopters of LTE, like the US, Japan, Sweden and Germany, are starting to fall behind in terms of data performance. In the US, for instance, LTE’s introduction in 2010 resulted in a huge base of LTE subscribers who are now competing for the same network resources, thereby slowing down average speeds.

Spectrum bands for LTE deployment

As of now, the majority (51 per cent) of 4G LTE networks worldwide are deployed on re-farmed 2G/3G spectrum in existing bands, while 22 per cent are on the 2600 MHz band and the remaining 27 per cent on digital dividend spectrum bands (700 MHz/800 MHz). Only 64 countries have assigned digital dividend spectrum bands for 4G network deployment. Meanwhile, 1800 MHz is the most common band for 4G, accounting for more than 30 per cent of global LTE deployments.

4G ecosystem

According to GSA, there are 4,416 LTE-enabled devices as of February 2016, an increase of around 67 per cent in comparison with February 2015. Smartphones account for the largest share (61.2 per cent) of these devices. Moreover, 98 per cent of LTE-enabled smartphones are multimodal, capable of operating on at least one 3G technology in addition to LTE. Almost 50 per cent of LTE phones can operate on 42 Mbps DC-HSPA+ networks. Globally, 275 smartphones support voice over LTE (VoLTE) as well. After smartphones, routers account for the highest share of LTE devices (18.5 per cent) followed by tablets (8.3 per cent).

Key challenges

Although operators are rolling out LTE services globally on a large scale, many challenges still need to be overcome for successful network deployment and broad consumer adoption. The main ones are:

  • Spectrum harmonisation: One of the main benefits of GSM networks has been the possibility of seamless roaming across countries, largely because of the presence of harmonised spectrum in large parts of the world. LTE infrastructure is being deployed on different spectrum bands in different countries and also by different operators in the same country. Thus, the burden of providing seamless global roaming shifts to the terminals (mobile devices) to support multiple frequency bands, leading to increased costs and complexity. This process is time-consuming and inefficient.
  • VoLTE: A prominent advantage of LTE is the converged evolved packet core (EPC), which has the ability to carry all types of traffic: voice, video and data. However, most standardisation processes have focused on LTE’s data aspects, neglecting voice. Different operators are according different levels of priority to this issue, with some early adopters considering data-only services for initial LTE roll-outs. The full opex and capex benefits of a converged EPC can only be realised when all traffic types are carried over a single and unified core. The issue of VoLTE standardisation gets even more complicated when taking into account the interlocking of LTE with different types of legacy networks like GSM, HSPA, CDMA2000, Wi-MAX and Wi-Fi.
  • Backhaul augmentation: The major challenge with wireless networks so far has been the limited availability of spectrum. However, in the case of LTE, the capacity bottleneck is shifted from the air interface to the backhaul link between base stations and the core network. Operators thus need to make significant investments in backhaul infrastructure when deploying LTE. To comprehensively address the backhaul challenge, operators will eventually have to use the full range of technologies like microwave, fibre/Ethernet, community access television Ethernet and Wi-MAX, further adding to costs.
  • Traffic management: LTE is deployed in larger spectrum bands for maximum bandwidth potential and increased spectral efficiency, thereby giving higher data rates. However, these gains will eventually be dwarfed by the faster rate of data traffic growth. According to AT&T Wireless, a 3G-enabled iPhone typically generates as much data traffic as 30 basic feature phones, and data traffic is much greater in case of LTE. Moreover, with the growth in data traffic, mobile operators need to look for the ability to offload internet traffic at the edge of their networks and not carry that traffic to and through their core networks.
  • Interoperability: A vibrant and robust ecosystem is essential for the wide deployment and adoption of LTE. To achieve deployment flexibility and lower operation costs, network operators need a strong infrastructure and device supplier base. They also need to be able to mix and match equipment from different suppliers in their networks.
  • Maintenance of multiple networks: Most operators who have launched LTE networks have both 2G and 3G networks in service. While they will continue to operate the three networks simultaneously in the near term, the 2G/3G networks operating on GSM are likely to be shut down in the long term. This will result in a significant loss in roaming revenues for operators as 80 per cent of worldwide users are still on GSM technology. Switching off GSM networks will enable operators to re-farm that spectrum, but there are many strict regulations around this spectrum in different countries, including complete nationwide coverage requirements.

Outlook

Despite the challenges, LTE is poised to attain significant growth in the near future. According to GSMA Intelligence, over 2.5 billion 4G LTE connections are expected worldwide by 2020, by which time 63 per cent of the world’s population will be covered by 4G LTE. Three out of five global LTE connections will come from the developing region in 2020, up from around three in 10 in 2014, largely driven by LTE growth in China.