In February last year, construction of the world's first 5G railway station began in Shanghai, China, signifying the start of commercial adoption of 5G indoor coverage. Mobile operators around the globe are actively deploying 5G indoor networks. This has resulted in significant implementation of 5G commercial applications in airports, shopping malls, exhibition halls, and other landmark buildings. The arrival of 5G has led to a growing importance of indoor coverage, and improving indoor coverage and user experience has emerged as an industry-wide consensus. Related industry forecasts have indicated that indoor scenarios will enable operators to achieve greater 5G business success, highlighting the significance of high-quality indoor coverage networks.

Indoor and Outdoor 5G Networks Must Be Constructed in Parallel

In the first wave of 5G construction, operators prioritized indoor places as key coverage locations. This is because indoor locations, including airports and railway stations, have already been traffic hotspots in the 4G era. Consequently, introducing 5G to these locations will improve capacity and user experience. Exhibition halls and sports stadiums were also top priorities as they provide operators with opportunities to build their 5G brands through successful network assurance. High-end hotels, office buildings, and shopping malls were preferred as these places are frequented by the first wave of 5G users. For operators, the experience gained from 4G deployments offered a valuable reference to understanding indoor data traffic and user distribution, and this guided them towards achieving increased targeted indoor coverage.

Parallel deployment of indoor and outdoor networks is already commonly practiced by operators across the globe. The majority of first-wave operators in Europe, the Middle East, and South Pacific, started constructing 5G indoor coverage networks when 5G deployment first began. For example, Switzerland's Sunrise listed large venues, office buildings, and service centers as key 5G coverage locations in the first wave of 5G construction. Operators in the Middle East were especially proactive deploying 5G networks in shopping malls, venues, and royal palaces during the initial stages of 5G adoption. In China, 5G deployment was started nearly in all indoor scenarios and indoor networks were deployed faster than other practices outside China. This shows the great importance operators all over the world have attached to 5G indoor coverage.

The high level of importance attached to indoor coverage is attributed to the fact that 70% of data traffic is generated indoors. Another reason includes the introduction of high-band spectrum, making it challenging to rely on outdoor networks to complete indoor coverage. 4G network analysis shows, given the same outdoor macro coverage, the area with weaker coverage on the 3.5 GHz band is doubled compared to the 1.8 GHz band for specific office buildings. This shows that improving the in-depth coverage in indoor areas has been an imperative priority for operators in the 5G era.

5G Indoor Coverage Is a Bridge Towards B2B Markets

The most noticeable thing distinguishing 5G from 4G is that 5G is able to enable industrial transformation and accelerate industrial digitalization. Purely outdoor industrial businesses, such as unmanned aerial vehicles (UAVs) and self-driving, account for a minor proportion of industrial businesses. A large majority of industrial customers and businesses are based indoors.

Moreover, both common users and industrial customers are present in each indoor scenario. For example, airlines are industrial customers in airports, stories in shopping malls, doctors and nurses in hospitals, and manufacturing workshops in factories, where a huge number of common customers are present. When delivering 5G indoor coverage to common users, operators are getting close to serving industrial customers. Therefore, 5G indoor coverage is a bridge in leading operators towards valuable new opportunities in industrial business.

In the Beijing Daxing International Airport, China Unicom has placed a top priority in providing passengers with mobile broadband (MBB) services through 5G networks. These services include high-speed Internet access, gaming, and entertainment. China Unicom has also cooperated with Huawei to provide China Eastern Airlines with 5G smart travel services. This is the first time 5G commercial services have been introduced to the aviation industry. It is a showcase for China Eastern Airlines in promoting smart travel services worldwide and provides China Unicom with valuable experience for future exploration of 5G industrial applications. In other industries, such as hospitals and factories, more businesses are embracing 5G, aiming to utilize the full potential of 5G. In China, by the end of 2019, more than 300 large hospitals introduced 5G indoor networks to their campuses. Remote ultrasound examination, video consultancy, VR ICU visits, and mobile ward round as well as many other smart applications have been implemented. This reflects the genuine existence of 5G demand throughout the medical industry.

Overall, operators develop industry markets gradually, with early-stage efforts focused on the industrial applications that are easier to implement. This will enable operators to seek the collaboration models and accumulate experience required to deal with the scenarios with demanding requirements. These indoor places having both common and industrial customers are ideal opportunities for them to achieve such purpose. After all, regardless of whether an indoor deployment is to serve common or industrial users at the first place, it would be extremely efficient to use just one 5G indoor network to serve both common and industrial users.

DIS Architecture Takes Center Stage and Differentiation Is Imperative

Fast growth in 4G traffic and commercial adoption of 5G are placing indoor networks under increasing pressure relating to capacity expansion and upgrades. Traditional distributed antenna system (DAS) networks do not support convenient expansion, network evolution, or quality user experience. They have long been stumbling stones hindering operators in terms of future development.

The decline of traditional technologies comes side by side with the rise of newer ones. Digital indoor system (DIS) is a new digital indoor coverage solution, which began to stand out in the medium phases of 4G growth. The new favorite has achieved broad recognition among operators in terms of experience, capacity, evolution, and network management. Many operators, including Hong Kong Telecom (HKT) and China Unicom, have all released their white paper on 5G indoor digitalization to describe their experiences and strategies in this regard. Global System for Mobile Communications Association (GSMA) is also calling for operators to fully prepare themselves for the transition to the next generation of digital indoor network architecture.

DIS has entered its positive uptrend in industry ecosystem. The world's leading consulting firm Dell'oro confirmed in its latest report that the shipment of global digital indoor access products has increased by nearly 50% annually on average over the past two years. Global leading equipment vendors as well as DAS vendors have all launched their indoor coverage solutions based on the DIS architecture. In 2019, Huawei's LampSite modules, as an example, accounted for more than 60% of its 5G shipment. Therefore, it is not only 4G capacity and experience but also 5G requirements are promoting DIS to take the center stage of indoor coverage networks.

Requirements will continue to further diversify in indoor scenarios, leaving DIS faced with enormous challenges in terms of traffic volume, building's internal structure and layout, and applications. For example, high-traffic and high-value buildings require solutions with higher integration and performance. Office buildings and hotels, in which the internal space is filled with partitions and the traffic demand is relatively low, require simpler and lighter solution. These places account for more than 60% of indoor construction excluding homes, becoming important scenarios where operators will compete in 4G and 5G indoor coverage. To take the "center" stage, all equipment vendors have no choice but to provide differentiated series DIS solutions that will help operators build indoor networks efficiently, while achieving 5G business success.