The core technology of 5G and 6G-millimeter wave

Compared with the previous 4G communication, 5G communication has many advantages, and the most intuitive one is undoubtedly “high-rate transmission.” It is known that the transmission speed of 5G will increase by 10 times or even 100 times that of 4G, and the theoretical download speed of 6G will be expected to reach 100 times that of 5G, which is 1TB per second! From 4G to 5G to 6G, why can the transmission speed be increased by a hundredfold? A key technology is involved behind this: millimeter wave (mmWave).

In the decades since the development of mobile communications, the most commonly used frequency band is Frequency range 1 (FR1) below 6GHz, the frequency range is 450MHz to 6GHz, commonly known as centimeter wave. Until the comprehensive coverage of 5G networks, people put forward higher requirements for bandwidth, and the communication frequency band will inevitably extend in the direction of “high-speed transmission”. According to the 3GPP agreement, 5G NR supports two major frequency bands: one is FR1 below 6GHz, and the other is Frequency range 2 (FR2) in the frequency range of 24.25GHz to 52.6GHz. Because the FR2 wavelength has been reduced to the millimeter level, it is called the millimeter wave band.

Compared with the frequency bands below 6GHz, the millimeter wave frequency band has abundant spectrum resources and has a huge advantage in carrier bandwidth. It can achieve large bandwidth transmissions of 400MHz and 800MHz. Through co-construction and sharing between different operators, ultra-high rate data transmission. At the same time, the millimeter-wave wavelength is short and the required component size is small, which facilitates the integration and miniaturization of equipment products and meets the mainstream needs of the current terminal market. Therefore, starting in 2019, millimeter wave technology has gradually taken the center stage of the civilian market, assuming the important task of providing better quality networks.

Global centimeter wave and millimeter wave band deployment

Image source: Qorvo official website

In fact, millimeter wave communication technology was mainly used in the military industry in the past. It was a special radar technology that used short-wavelength electromagnetic waves. Thanks to the rapid iteration of 5G and 6G communications, millimeter waves have been able to open up the civilian market and become a major development direction of the global communications industry. At the beginning of 2019, millimeter wave-related product and policy information was spread frequently, and technological progress exceeded expectations. Even Ren Zhengfei, the founder of Huawei, was a “platform” for the technology. He once publicly stated: “Huawei’s success in 5G technology is due to the centimeter wave; the 6G millimeter wave is the general direction!”

It is worth mentioning that Huawei’s deployment of millimeter wave technology was earlier. During the 3rd Tokyo Bay Global 5G Summit in June 2017, Huawei and NTT DOCOMO completed the 39GHz high-frequency technology test based on the 3GPP 5G new air interface for the first time, realizing three-party real-time 4K HD video conferencing. In February 2018, Huawei and Canadian operator Telus tested a 28GHz system in Vancouver to provide fixed wireless broadband access services. In October of the same year, Huawei opened the world’s first 3GPP-based 5G millimeter wave commercial Firstcall, which marked the maturity of the 3GPP-based 5G millimeter wave network and related industry chains, and China’s 5G millimeter wave applications began to set sail. In August 2019, Huawei demonstrated the use of the folding screen mobile phone HUAWEI Mate X to communicate with the base station through millimeter wave technology to play 4K high-definition video online. It is the world’s first mobile phone with a folding screen to open up 5G millimeter wave end-to-end communication in a real network environment. factory.

Coming to mid-2020, good news about the 6G millimeter wave layout is coming. Recently, Yang Tao, vice president of Huawei’s China Operator Business Department, publicly disclosed that Huawei is already participating in 6G-related pre-research work. It has pre-researched 6G mainly using millimeter wave bands, and is in the stage of scene mining and technology search. According to Huawei’s estimates, there will be some 6G usage in 2030, and Huawei is currently actively participating in this area.

However, there are still many bottlenecks in the current 5G millimeter wave technology layout, requiring leading communications companies to lead their local supply chains to break through. For example, the landing application of millimeter wave technology still faces many urgent problems and technical challenges such as spectrum planning, domestic high-frequency device industry capabilities, and system testing solutions. These are all technical bottlenecks that the millimeter wave industry must overcome.

Many countries are betting on millimeter waves, and the competitive landscape has basically taken shape

5G commercialization will usher in a peak in 2020, and 6G pre-research has also been put on the agenda, and the upstream and downstream industry chain companies that deploy millimeter wave technology in advance may usher in opportunities.

Judging from the current 5G millimeter wave pattern, the United States, South Korea, Japan and other countries have successively completed the division and auction of 5G millimeter wave spectrum. The prospects for 5G commercial deployment are clear and the industrial chain is relatively concentrated. In the early stage of their millimeter wave deployment, most countries focused their attention on the two frequency bands of 26GHz and 28GHz, and the resources invested in these two frequency bands are also the most.

At the same time, multiple operators, including Verizon and T-Mobile in the United States, NTT in Japan, and KT in South Korea, have begun testing and applying millimeter wave 5G systems in the country, and have made positive progress. For example, in January 2018, T-Mobile, Nokia and Intel in the United States also tested 28GHz high-frequency systems in Washington, mainly using high-frequency communications to provide users with fixed wireless broadband access services; another example is Korea Telecom in February 2018 ( KT) Implemented 28GHz 5G network applications at the Pyeongchang East Olympics, using the North American operator’s V5G system, etc.

As for China, the communications industry has also begun to consider 5G millimeter wave deployment and application issues from the perspective of system applications. Last year, China Mobile revealed that it has completed the verification of 5G millimeter wave key technologies and plans to realize the commercial deployment of 5G millimeter wave in 2020. But frankly speaking, the relevant domestic research is still relatively scattered, and a clear 5G millimeter wave mobile communication system application direction and deployment plan have not yet been formed. The resistance mainly comes from three aspects:

1. China’s millimeter wave spectrum plan is not yet clear, and the government needs to clarify the millimeter wave spectrum plan as soon as possible to accelerate the development of the millimeter wave industry chain.

2. The maturity of my country’s 5G millimeter wave industry chain lags behind 5G low-frequency, and also lags behind the international advanced levels of the United States and Europe. It is manifested in the single form of millimeter wave equipment, the functions and performances still do not meet the needs of 5G networking, and the small number of 5G millimeter wave chips and terminal models, and the insufficient coverage and form of two aspects. Among them, the hindering factors mainly come from high-frequency devices, including: high-speed and high-precision digital-to-analog and analog-to-digital conversion chips, high-frequency power amplifiers, low-noise amplifiers, filters, integrated package antennas, and so on.

3. There is a shortage of low-cost, high-reliability packaging and testing technologies. Traditional mobile communication radio frequency testing is based on conduction testing, while 5G millimeter wave testing can only use the OTA test method in a darkroom environment. At present, the cost of test site, test efficiency, and test accuracy are all issues that need to be considered for OTA test programs and solutions are given.

Although the overall industry started late, China’s 5G millimeter wave industry is gradually catching up and is expected to open up a huge incremental market. At the end of last year, the industry consulting company TMG predicted that the economic benefits of using millimeter wave frequency bands in China will have an effect of approximately US$104 billion by 2034, accounting for approximately the estimated contribution of millimeter wave frequency bands in the Asia-Pacific region (estimated to reach 2,120 Billion dollars).

In terms of specific vertical industries, manufacturing and utilities such as water and electricity have the largest contribution, accounting for 62% of the total contribution; followed by professional services and financial services, accounting for 12%; information communication and trade, accounting for 10%; and then It is agriculture and mining, and finally public services. In the long run, as the use of 5G millimeter waves continues to grow, this economic advantage, coupled with the many potential industrial applications of 5G millimeter waves, will contribute to the significant impact of vertical industries on GDP.

In this regard, it is imminent to promote the localization of the millimeter wave industry. Some industry players said that the mobile communication industry urgently needs operators to issue clear signals, put forward the overall needs of the 5G millimeter wave new air interface system, clarify the development plan of equipment and terminals, promote the maturity of the millimeter wave industry chain, and prepare for future deployment .

Inventory: 5G millimeter wave industry chain

From the perspective of the industry chain, the millimeter wave industry chain is composed of equipment manufacturers, chip manufacturers, terminal manufacturers, antenna manufacturers, and vertical industries. The following table lists some representative companies:

1. Millimeter wave equipment

From a technical point of view, the millimeter-wave baseband part has the same maturity as 5G low-band equipment, but the radio-frequency-related functions and performance are far behind 5G low-band equipment. In terms of main equipment, since North America, Japan and South Korea have already begun to deploy millimeter wave systems, the frequency bands for manufacturers’ equipment are mainly North America, Japan and South Korea. The device can support basic functions, but some functions such as beam management and mobility need to be further improved. Representative companies are: Ericsson, Nokia, ZTE and other manufacturers.

From the data point of view, in terms of bandwidth and peak rate, millimeter wave equipment should support 200MHz, 400MHz single carrier capability, multi-carrier aggregation, and a total bandwidth of 800MHz. Millimeter wave equipment should support 64QAM and 256QAM modulation methods, and the peak transmission rate of the system should reach more than 10Gbps.

In addition, equipment needs to provide flexible deployment capabilities. Compared with sub 6G equipment, the size of millimeter wave components is smaller, and more antenna elements can be deployed per unit area or millimeter equipment is easier to miniaturize. The equipment needs to be optimally designed to reduce the size of the micro-station and micro-AAU unit equipment, beautify the design to facilitate concealed deployment, and provide a variety of power supply schemes and return schemes.

2. Chip

As for chips, although major chip manufacturers around the world have released 5G millimeter wave related products, the progress is generally behind the equipment, mainly in the R&D and testing stages, and actual commercialization is still in progress.

According to incomplete statistics, there are many 5G chips related to millimeter wave technology on the market. Intel (Intel) released the XMM 8060 5G multimode baseband chip in November 2017. The chip supports both the sub-6GHz frequency band and the 28GHz millimeter wave frequency band. Qualcomm has been able to provide commercial millimeter wave terminal chips X50 and X55, and antenna module QTM525.

As for Qualcomm’s second-generation 5G NR modem, the Snapdragon X55 5G modem, it is a 7-nanometer single chip that supports 5G to 2G multi-mode, as well as 5G NR millimeter wave and frequency bands below 6 GHz. Among them, the new RF front-end solutions include QTM525 5G millimeter wave antenna modules, which can support the design of slim 5G smartphones with a thickness of less than 8 millimeters. At present, 20 OEM manufacturers around the world have carried out related product research and development, and 18 operators around the world are also using X50 5G modems for mobile trials.

In early 2019, the Federal Communications Commission (FCC) of the United States has certified the 5G module released by Motorola. The 5G module is equipped with a proximity sensor. Its function is to turn off 4 millimeter wave antenna modules before the user’s face approaches the phone to reduce the impact of radiation on the user; in addition, if the proximity sensor detects that the finger is blocking the antenna, the 5G module will strengthen Antenna power to achieve better reception of 5G signals.

As for domestic companies, as the subsidiary of H&T is in the field of domestic microwave and millimeter wave T/R chips, private companies that master core technologies except for a few national defense research institutes have strong technological scarcity in China. It can be completed in the data interface, and it can also expand some high-end applications.

3. Antenna

Massive MIMO and beamforming technology are one of the key technologies of millimeter wave systems, so the antenna industry is also worthy of attention.

Generally speaking, the antenna is a wire with a specified length, so it can be manufactured on PCB and FPC. However, due to the miniaturization and portability of the equipment, the design space left for the antenna is already very small, so the current mainstream solution is to use FPC to manufacture the antenna, that is, the foldable antenna. The foldable antenna is made of a soft board and can be bent into any shape to meet people’s higher requirements for the size and design of portable devices.

As the wavelength of millimeter waves is greatly reduced, the problem is that the diffraction ability of electromagnetic waves becomes worse, and the attenuation becomes abnormally obvious. Therefore, in order to improve attenuation and increase transmission speed, 5G technology will adopt MIMO multi-antenna technology, beamforming beamforming, and spatial hierarchical multiplexing technologies.

4. Terminal

Many industry players predict. 5G mobile phones will drive the first wave of terminal consumption of millimeter wave products.

In terms of commercial terminals, OPPO/VIVO/ZTE all expected to launch X55 chip prototype terminals by the end of 2019, and commercial terminals are expected to appear in 2020. Apple is already secretly launching the research and application of millimeter wave technology. Its 5G version of the iPhone that supports millimeter wave will be launched in December 2020 or January 2021, at least three later than the regular version (supporting 5G in the Sub-6G band) Months show the complexity of the commercial use of millimeter wave technology.

There is also news that TSMC has won an order for Apple’s 5G antenna packaging, and it is specifically aimed at 5G millimeter wave system integration.

Regardless of whether the above-mentioned mobile phones can be launched as scheduled, this series of news has brought small surprises to those concerned about 5G millimeter wave applications.

China Unicom believes that in the face of diverse 5G millimeter wave application scenarios, especially campus private network scenarios, millimeter wave terminals should be customized according to the needs of private network services. According to 5G millimeter wave application scenarios, millimeter wave terminals include public and private network hybrid terminals, private network function terminals, and customized CPE. The specific requirements are as follows: public and private network hybrid terminals, integrated design with 5G terminals, supporting multi-mode and multi-frequency, Support 5G high and low frequency dual connection and 5G millimeter wave carrier aggregation capabilities. Support private network APP application. The terminal’s other capability requirements are the same as the current public network terminal.

5. Scenario application

The vertical application scenarios of 5G millimeter wave are rich and diverse, whether it is personal terminal consumption, industrial manufacturing, medical and health and other markets, it will also give birth to a large number of applications. These innovations include enhanced telemedicine and education, industrial automation, virtual and augmented reality, and more.

In terms of medical treatment, telemedicine can achieve a more accurate and fast level through the speed and low latency supported by the millimeter wave spectrum. This includes sensing network functions, using remote sensors and wearable devices that are always connected to enhance preventive medicine, as well as remote surgery and “smart” instruments.

In the field of industrial manufacturing, a new generation of robots, remote object manipulation (remote precise control of machines), drones, and other real-time control applications in digital industrial centers are expected to improve efficiency, reduce costs, enhance safety, and bring Product and process innovation. This is one of the effective means to improve the current uneven level of manufacturing intelligence.

In terms of autonomous driving transportation, 5G millimeter waves will allow unmanned vehicles to communicate with each other, as well as with the cloud and the physical environment, thereby establishing an efficient public transportation network. In the future, these and many other innovative use cases are expected to account for 25% of the total value created by 5G.

In addition, from the perspective of enterprises and industries, indoors, parks, docks, etc.