Standard landing, commercial sprint. However, on the road of 5G rushing all the way, the shortage of spectrum resources has become a major obstacle.
Compared with any previous generation of communication systems, 5G needs to meet more diversified scenarios and extreme performance challenges, so the candidate frequency bands that support the new 5G standard need to be deployed in full frequency bands. However, the low frequency bands are already extremely crowded, and most of them involve Other system interference protection. In most parts of the world, the most direct way is to use higher frequency frequency bands, including the 3GHz frequency band below 6GHz and the millimeter wave frequency band above 24GHz. Compared with the low frequency, these frequency bands have more available bandwidth.
In the process of searching for new spectrum resources, my country is also facing an unprecedented shortage of spectrum resources. 4G has gradually consumed high-quality frequencies in the low frequency bands, so my country took the lead in dividing low frequency frequency bands for 5G. According to the plan, my country’s 5G frequency band resources are mainly concentrated in the 3.5GHz and 4.8GHz frequency bands. The millimeter wave, which has attracted much attention before but has been stuck in the stage of soliciting suggestions, is also expected to make progress.
At the 5G and future network strategy seminar that ended not long ago, Chen Lidong, deputy director of the Communication Development Department of the Ministry of Industry and Information Technology, requested that the evolution of mobile communication air interface technology, millimeter wave and other new technology fields be strengthened. The Special Working Group on 5G Microwave and Millimeter Wave Technology specially established by the Committee for the Promotion of Future Mobile Communication Technology and Standards Development released a white paper on 5G millimeter wave spectrum planning recommendations, calling on my country to clarify the 5G millimeter wave spectrum layout and establish the available frequency bands as soon as possible. Plan 24.75~27.5GHz and 37~42.5GHz to give the industry a clear direction. It is recommended that the frequency plan be completed by the end of 2018 to support the millimeter wave pre-commercial trial in 2019 and the large-scale commercial deployment of millimeter wave in 2020.
In fact, in my country, millimeter wave technology is not a technology that has never been involved before. In this regard, Qualcomm, which has made important contributions to the aforementioned white paper, has a profound experience. Xu, the company’s head of R&D in China, said that through exchanges with many Chinese manufacturers and partners, China’s accumulation of millimeter wave technology is not weak, and many research institutions and universities have relevant research accumulations in base station technology. There is also a certain degree of application. “In fact, millimeter wave technology has been applied in many fields, and we now need to promote this technology to a wider range of commercial applications.” The reporter learned that at the level of technical support, including multi-antenna technology, broadband automatic processing capabilities, etc. , my country already has a certain technological reserve as the basis of millimeter wave technology, and may first use the frequency band technology below 6GHz. At present, many Chinese operators and manufacturers are actively promoting the application of millimeter wave technology in this frequency band.
Looking at the world, planning for millimeter waves is the general trend. At present, in the frequency band below 6GHz, we see frequency bands around 3GHz gaining attention around the world. Many countries around the world are allocating or planning to allocate millimeter wave frequency bands above 24GHz. In July 2016, the United States divided up to 11GHz millimeter wave spectrum into 5G frequency bands. Other regions including Europe, South Korea, Japan, Australia and Canada are also allocating millimeter wave spectrum for 5G. In some cases, part of the millimeter-wave spectrum may be divided into shared or unlicensed spectrum—rather than licensed spectrum, which may be necessary under certain circumstances.
“There is no doubt that millimeter wave spectrum is essential for 5G in China and globally. Millimeter wave frequency bands can provide extreme bandwidth, so it is essential to meet the needs of better and faster enhanced mobile broadband. Compared with gigabit LTE services in China and other parts of the world, the millimeter wave frequency band can provide a significant difference for 5G.” Xu thinks so.
This importance is evident in the comparative data in a series of tests. In this regard, Qualcomm conducted a series of 5G real network simulation experiments. A 5G network simulation experiment was conducted in the San Francisco experiment in the United States. The existing LTE base station was supplemented with millimeter wave capacity to achieve 5 times the network capacity gain. At the same time, when 4G reached 100% coverage, the millimeter wave Joining the existing 4G base station can achieve 65% coverage of the 5G network. Another set of experiments in Frankfurt is a simulation experiment of converting 4G to 5G on the frequency spectrum below 6GHz. As far as the download rate is concerned, the average value of 4G users has increased from 56Mbps to the average value of 5G users of more than 490Mbps, which is 8.8 times faster. The gain, in terms of burst data at the edge of the cell, can reach a gain of 9.2 times.
Thanks to the results of the experiment, Qualcomm has now developed and demonstrated a test platform that utilizes the two frequency ranges below 6GHz and millimeter wave, and has launched the Snapdragon X50 modem that can support 5G new air ports operating in the below 6GHz and millimeter wave frequency bands. .
Regarding the challenge of millimeter wave, Xu Ye frankly said: “The use of millimeter wave frequency band transmission is more likely to cause path obstruction and signal attenuation. Therefore, the efficiency and robustness of millimeter wave signal transmission is one of our research and development priorities. Making the millimeter wave technology better adapt to the size and power consumption of the terminal is also the direction of Qualcomm’s technical research.”