China Mobile has made remarkable achievements in 4G network construction. And Shanghai is riding the crest of a wave of 4G construction in China.
By Wang Qiang
Shanghai, China's pearl of the Orient, is an international city that stands at the forefront of rapid development in China. Equally, China Mobile is the nation’s leading telco. In the span of three short years from when the operator began building a 4G network in 2013, China Mobile has deployed over 1.32 million 4G base stations and its 4G subscriber base has grown to more than 429 million.
Shanghai covers an area of 6,340 square kilometers and has a population of 25 million. Shanghai Mobile has 22 million subscribers, including 10 million 4G users. The operator has built 20,000 4G base stations, which provide 99.5 percent 4G service coverage. Shanghai Mobile's is the dominant player in the Shanghai communications market.
Phase 1 (2012-2013)
In the 3G era, China Mobile was constantly playing catch-up thanks to a poor user experience. To turn things around, China Mobile kick started a 4G expansion pilot project in 2012 on trial networks, Shanghai Mobile deployed 1,000 4G sites, and carried out network verification, accumulating technical expertise and experience. This later helped the operator rapidly implement the widest 4G network coverage in the city. Today, Shanghai Mobile's 4G network service coverage has hit 99.5 percent thanks to a range of innovations.
Capacity of existing macro stations maximized through cooperative F/D RF solution
Shanghai Mobile's 4G network macro stations cover F (2010-2025 MHz) and D (2575-2635 MHz) bands. Growth in services, especially VoLTE services, led to requirements for deep coverage. But it was becoming increasingly difficult for Shanghai Mobile to acquire macro station sites with traditional way.
Shanghai Mobile worked with Huawei to solve this problem. The partners introduced D-band RRU (remote radio units) that could support F-band signal reception during the network capacity expansion phase. In addition, algorithms were deployed that gave F-band reception capability to the new modules and existing sites that would be used together. This supported 16 upstream channels, increasing the system's reception power and enhancing F-band upstream coverage by 3 dB. This solution greatly boosted F-band coverage. Shanghai Mobile has now widely deployed this solution, ensuring network capability for services such as VoLTE, which require deeper coverage.
Exploring micro station resources to enhance the deep coverage and capacity
The cooperative F/D RF solution has helped improve coverage capability. However, it didn’t meet all coverage requirements. New station acquisition remained a necessary area in which to explore new solutions. As a large international city, Shanghai has many security and surveillance poles that need provide a potential platform for new cell sites.
Shanghai Mobile's innovative solution involved cooperating with the Shanghai public security bureau by sharing big data in exchange for acquiring poles for site deployment. By analysing mobile user data in cells in its coverage area, Shanghai Mobile can obtain real-time information on the source, number, distribution, and flow trends of people in the area. This kind of information is also useful for the police and security services.
Shanghai Mobile first conducted a pilot on the Bund area, deploying 20 micro stations on surveillance poles. The pilot helped improve coverage and gave security services valuable information. Following the pilot, the scheme entered its second phase at the end of 2015. Shanghai's public security systems provide over 300 surveillance poles, covering the City God Temple, Xintiandi, and Lujiazui areas of Shanghai.
Phase 2 (2014-2015)
At the end of 2013, China issued 4G licenses, and the mobile market in China boldly stepped into the 4G era. With the big three operators all making a big push for 4G, a question that concerned China Mobile was how to ensure its competitive advantage. The heart of Shanghai Mobile's strategy was user experience. The operator actively promoted the commercial adoption of VoLTE while continuing to leverage new 4.5G technology. The aim was to not only consolidate its lead in voice experience rankings, but also to create a faster data rate experience.
Leveraging mobile spectrum and TDD technology to increase network speeds and build capabilities for the fastest 4G network
In 2014, Shanghai Mobile rolled out 2CC CA in the City God Temple and Xintiandi areas, attaining a downstream rate of 220 Mbps. In 2015, the operator successfully piloted DL 3CC CA, UL 2CC CA, and 64QAM technologies, increasing download speeds to 330 Mbps and upload speeds to 30 Mbps. In 2016, Shanghai Mobile attained a download rate of 1 Gbps and upload rate of 50 to 60 Mbps through the use of 4x4 MIMO and 256/64QAM. By enhancing network speed capabilities, Shanghai Mobile stepped into the Gigabit era in 2016.
China Mobile became the first operator to roll VoLTE out city-wide, enhancing 4G users' voice experience
Voice services are the key to China Mobile's growth and the main part of its business. Developing VoLTE service is a strategic focus for China Mobile in the 4G era. One factor behind this strategy is to enhance user voice experience by increasing voice quality from its original 2G level. Another is to free up valuable 2G spectrum by shifting the 2G network voice load to the 4G network, and thus create a flexible strategic reserve of spectrum for future use.
Shanghai Mobile launched commercial VoLTE trials in 2015, the culmination of a year of comprehensive preparations in 2014. In 2016, with the rapid maturation and proliferation of 4G handsets, Shanghai Mobile rolled out VoLTE to customers, increasing the number of customers using the service.
Phase 3 (2016-)
Shanghai Mobile currently has 10 million 4G subscribers, which is expected to exceed 15 million by the end of 2016. In some hotspots, it’s difficult to meet experience requirements by traditional expansion. This has become a priority issue for Shanghai Mobile as it enters the mature phase of 4G network development.
Shanghai Mobile's solution has been to 4G-ize 5G tech by using future 5G technologies in its current network to increase network capacity fivefold, which will help it easily deal with the challenge of explosive service growth.
Deploying Massive MIMO boosts network spectrum efficiency
Massive MIMO is a key 5G technology that uses a large-scale antenna matrix to support extremely powerful three-dimensional beamforming and algorithms. The technology boosts network traffic capacity to realize a fivefold increase in spectrum efficiency compared to traditional 8T8R networks, greatly enhancing mobile network capability.
Shanghai Mobile carried out the world's first Massive MIMO pilot on a commercial network in September 2015. On the 2615-2635 MHz band, 16 commercial handsets (Huawei Mate 7) attained total cell throughput of 670 Mbps and 340 Mbps cell throughput when carrying out 50 percent scrambling on nearby networks. Compared to the existing 8T8R network, this was a five-to-sixfold increase on network capacity.
Huawei and Shanghai Mobile worked together to develop an innovative Massive MIMO solution that uses BBU+AAU split architecture. This allowed the parties to leverage their experience of traditional BBU+AAU network deployment, facilitating project implementation and maintenance. In addition, the solution enables the full potential of baseband to be leveraged, enabling subsequent adaptations based on algorithms and network evolution requirements to be carried out to lay the foundation for continual performance improvements and evolution to 5G.
In 2016, Shanghai Mobile will improve the technical requirements of Massive MIMO and further explore commercial scenarios by taking into account real-world requirements and scenarios.
Super base stations and user experience-centric network construction will ensure industry leading user experience
As networks continue to grow, Shanghai Mobile and Huawei will continue to explore ways to continue optimizing user experience on networks in the future by unleashing the full potential of traditional sites. These methods include super base stations, construction strategies for user experience-centric networks, interference suppression technology and algorithms, and flexible site construction solutions.
Continuous innovation has helped Shanghai Mobile to solidify its competitive advantage. The operator dominates the market, with close to 80 percent of mobile subscribers and almost 90 percent of 4G subscribers in Shanghai. It’s also made significant improvements in terms of user DOU and average revenue per user. China Mobile's shining oriental pearl, Shanghai Mobile, has continually tapped into the power of 4.5G. Through continuous innovation, it’s consolidating its network capabilities, building a superior experience, and developing new site mode. The operator's wireless communications business will continue to go from strength to strength.
