5g has begun to be commercialized on a large scale, and the key technologies of 5g in the next stage also begin to attract people’s attention. Due to its high bandwidth, low delay and other advantages, millimeter wave can release 5g key potential, thus realizing the revolutionary improvement of business experience and helping the digital transformation of Qianxing Baiye.
GSMA predicts that millimeter wave, as the core enabling technology for high-speed access to industrial automation, health care, intelligent transportation and virtual reality, will contribute $656 billion to global GDP by 2035, accounting for 25% of the total contribution of 5g. Nowadays, the development of millimeter wave industry has become the focus of attention.
22 operators have deployed millimeter wave in the world
With the development of 5g and the expansion of industry application, the communication frequency band is developing towards millimeter wave. The biggest advantage of millimeter wave is that the frequency band resources are rich, the bandwidth can reach 400MHz or even 800MHz, and the transmission speed can reach 10Gbit / s. Because of high frequency and small antenna size, the terminal can integrate more antennas to form a narrower beam. Both millimeter wave base station and mobile phone supporting millimeter wave can realize high-speed data transmission by carrier aggregation or beam aggregation, which supports dense spatial multiplexing while reducing interference.
The following two frequency bands are deployed: 5g band and 5g band. ITU has planned the relevant frequency band for the development of millimeter wave. In November 2019, ITU World radiocommunication Conference (wrc-19) determined more frequency bands for 5g, including 24.25-27.5ghz, 37-43.5ghz, 45.5-47ghz, 47.2-48.2ghz and 66-71ghz. Currently, millimeter wave deployment is mainly carried out in North America, Europe, Asia and Australia. According to the data in August 2020, 22 operators have deployed millimeter wave 5g systems worldwide. The United States, Japan and South Korea have mainly deployed commercial networks in the 28ghz frequency band. At the same time, the United States is still considering the commercialization of 26ghz.
Li Fuchang, deputy director of wireless technology research department of China Unicom Research Institute, said that in general, millimeter wave can be applied to three types of scenes. The first type is network-based data hotspot scenarios, which have a large demand for network traffic, such as traffic hubs, airports, squares, stadiums, pedestrian streets, etc. In this scenario, millimeter wave is deployed to form the high-throughput layer of the network to solve the problem of network capacity. The second category is the smart park scenario. Millimeter wave can be combined with AI technology to overlay rich intelligent services, providing solutions with large capacity, high speed and localization of the park, and providing services for the private network of the park. The third type is fixed wireless broadband access, which can provide some broadband access services through millimeter wave. In addition, as a partner of the Olympic Games, China Unicom is committed to building a broadband wireless Olympic Stadium.
R17 version will adapt to more millimeter wave scenes
Millimeter wave is progressing well in terms of standards. The 3GPP R15 version brings millimeter wave into the scope of work. In the R15 stage, the basic functional version of 5g NR including millimeter wave is given. The R16 version is optimized and the R17 version is further enhanced.
For millimeter wave, 3GPP has developed solutions based on large-scale multi antenna technology, and has also formulated relevant system information design, etc., and has defined relevant functions based on management, such as QCR design of antenna port, recovery mechanism based on beam failure, etc. these technologies can meet the basic deployment requirements of millimeter wave. Li Nan, deputy director of the Wireless Technology Research Institute of China Mobile Research Institute, said that in the standardization work of R16, 3GPP focused on improving the working efficiency of millimeter wave system and reducing the delay and cost of millimeter wave communication. For example, in the R15 standardization stage, the configuration of millimeter wave is mostly based on RC configuration, with relatively long period and large delay. In the process of R16 standardization, the default configuration is introduced to solve this problem, which enables millimeter wave to complete relevant configuration more quickly and obtain better performance.
The R17 version has further enhanced the millimeter wave performance and can adapt to more scenes. A new beam mechanism is introduced for medium and high-speed mobile scenes (such as 30km / h), so as to realize the control channel switching, meet the needs of system work more quickly and achieve higher communication rate. It is understood that 3GPP will introduce more 5g NR enhancement features supporting millimeter wave in R17 and future versions, such as optimizing IAB to support distributed deployment. This enhancement feature can help introduce full duplex operation and mobile relay (such as automobile) to improve capacity, coverage and service quality. R17 and future versions will also introduce optimized network coverage and beam management to reduce system overhead, enhance performance and improve network coverage.
In R17 and future versions, the millimeter wave spectrum will be further expanded to support 52.6ghz to 71ghz and license free bands, which will greatly expand the spectrum utilization range. The future version will also support new use cases other than embB, extend millimeter wave to the use cases of urllc and industrial Internet of things, and will also support enhanced positioning technology to provide positioning performance enhancement for a wide range of use cases and achieve centimeter level positioning accuracy.
Chips, terminals and modules are ready to go
In order to further promote the development of millimeter wave technology, millimeter wave industry chain enterprises have started research and development work. Qualcomm has overcome many obstacles in millimeter wave technology and commercialization. It can not only provide millimeter wave modem, but also provide end-to-end system design. Luo Tao, senior director of engineering and technology of Qualcomm, said that Qualcomm has launched millimeter wave module, which can integrate antenna, RF front-end and transceiver in a very compact size. A mobile phone can integrate multiple millimeter wave modules, which can not only meet the design requirements of compact and thin smart phones, but also meet the low-power consumption requirements of smart phones and maximize performance.
After the chip module is available, terminal manufacturers should also solve the problem of installing millimeter wave into smart phones. If the millimeter wave is put into the mobile phone, there will be three challenges: first, the road damage is relatively high, and the coverage is limited; second, if the traditional antenna and chip separation method is adopted, it will lead to very low efficiency and serious heat; third, millimeter wave is easy to be covered by objects, especially in the design of mobile phone, the shielding of hand or human body should be considered. With the efforts of all parties, millimeter wave mobile phone has become a reality. “The one plus millimeter wave version was launched in North America on April 29. It’s a very lightweight flagship with a thickness of 8mm and hardware support for 2 × 2 MIMO.” Zhong Yongwei, senior Wireless Engineer of Yijia mobile phone, said. Yijia mobile phone has cooperated with Ericsson’s commercial base station to complete the imt-2020 millimeter wave terminal test in 2020.
Future development of millimeter wave
As a matter of fact, with the evolution of 5g, millimeter wave will also gain stronger ability to support more application scenarios. According to Wang Wei, senior standardization manager of Ericsson (China), 5g is only in the initial stage. R17 will introduce 5g NR products with low complexity and high reliability to help millimeter wave expand to new terminal types, bringing enhanced experience of excellent speed and unlimited capacity. R17 will enable more new services, make full use of new spectrum resources, and release 5g millimeter wave potential in an all-round way.
The millimeter wave network will be ready soon. Experts of China Mobile think that millimeter wave will have the ability of large-scale commercial use in 2022, and hope to deploy millimeter wave network on the basis of SA architecture. At the same time, aiming at the bottleneck problems in the development of millimeter wave technology, including outdoor coverage, indoor coverage and dramatic changes in signal after occlusion, new networking technologies and implementation schemes are proposed Research and exploration.
Millimeter wave applications are also in the process of continuous development. Wang Jianli, chief engineer of ZTE wireless product planning, believes that in 2019-2020, FWA will be the main application of millimeter wave. With the development of the 2021 Winter Games, mbeb has been widely used. By 2022, with the introduction of R16 and R17 standards, millimeter wave will play a greater role in industrial Internet and more enterprise applications. It can be expected that the potential of 5g will be fully released after the millimeter wave scale commercial application.
Editor in charge: Tzh