In November 2016, the 3rd World Internet Conference held in Wuzhen , the prototype of 5G technology brought by Qualcomm, which could realize the “Internet of Everything” was selected into 15 “black technologies” - the world's leading Internet achievement. 5G advances to Gigabit mobile networks and artificial intelligence 
The fifth generation of mobile phone mobile communication standards, also known as the fifth generation mobile communication technology, foreign language abbreviation: 5G. It is also an extension of 4G and is under study. Currently there is no public specification or official document referring to 5G from any telecommunication company or standard setting organization (such as 3GPP, WiMAX Forum and ITU-R).
China (Huawei), South Korea (Samsung Electronics), Japan, and the European Union are all investing considerable resources in the development of 5G networks.
On December 21, 2017, at the 78th plenary session of the 3GPP RAN of the International Telecommunication Standardization Organization, the first version of the 5G NR was officially frozen and released.  On February 23, 2018, Vodafone and Huawei completed the first 5G call test .
The fifth generation of mobile phone mobile communication standards, also known as the fifth generation mobile communication technology, foreign language abbreviation: 5G. It is also an extension after 4G. Under study, the theoretical downlink speed of the 5G network is 10Gb/s (equivalent to a download speed of 1.25GB/s).
Nokia cooperated with Canadian operator Bell Canada to complete the testing of the first 5G network technology in Canada. The spectrum in the 73 GHz range was used in the test and the data transmission rate was 6 times that of the existing 4G network in Canada. Given the cooperation between the two, external analysis of Canada is likely to start full deployment of 5G networks within five years.
Due to the rapid development of Internet of Things, especially Internet and other industries, it has higher requirements for network speed, which undoubtedly has become an important factor in promoting the development of 5G networks. Therefore, both the Canadian government and the rest of the world are vigorously promoting the 5G network to welcome the next wave of technology. However, from the current situation, the 5G network is expected to take 4 to 5 years before it is commercialized. The
In February 2013, the European Union announced that it will allocate 50 million euros. Accelerate the development of 5G mobile technology and plan to introduce mature standards by 2020.
On May 13, 2013, South Korea’s Samsung Electronics Co., Ltd. announced that it has successfully developed the core technology of the 5G mobile communications (5G), which is expected to begin commercialization in 2020. The technology can transmit data at a speed of more than 1 Gbps per second over the 28 GHz ultra-high frequency band and can transmit up to 2 km. In contrast, the current fourth-generation Long Term Evolution (4GLTE) service has a transmission rate of only 75 Mbps. Previously, this transmission bottleneck was generally considered by the industry to be a technical problem, and Samsung Electronics used 64 adaptive antenna array transmission technology to solve this problem. Compared with the transmission speed of South Korea's current 4G technology, 5G technology is expected to provide 100 times faster speed than 4G Long Term Evolution (LTE).  Using this technique, it takes only 10 seconds to download a high-definition (HD) movie.
As early as 2009, Huawei had already conducted early research on related technologies and demonstrated the 5G prototype base stations to the outside world in the following years. On November 6, 2013, Huawei announced that it will invest 600 million U.S. dollars in the research and development of 5G technologies by 2018, and predicts that in 2020, users will enjoy 20Gbit/s commercial 5G mobile networks.
On May 8, 2014, Japanese telecom operator NTT DoCoMo officially announced that it will cooperate with six vendors such as Ericsson, Nokia, and Samsung to begin testing high-speed 5G networks that exceed the 1000 times network carrying capacity of existing 4G networks. The transmission speed is expected to reach Increase to 10Gbps. It is expected that outdoor testing will begin in 2015 and it expects to begin operations in 2020.
On March 1, 2015, the British "Daily Mail" reported that the United Kingdom has successfully developed a 5G network and conducted data transmission tests within 100 meters. The data transmission rate per second is as high as 125GB, which is 65,000 times that of 4G networks. Theoretically, 1 In seconds, 30 movies can be downloaded, and it is said to be put into public testing in 2018 and officially put into commercial use in 2020.
On March 3, 2015, the European Union’s digital economic and social committee member Guzel Ortinger formally announced the EU’s 5G company’s cooperation vision and strives to ensure that Europe’s voice in the next generation of mobile technology global standards. Otinger said that the 5G public-private partnership vision will not only involve the integration of optical fiber, wireless and even satellite communications networks, but will also use software-defined networking (SDN), network function virtualization (NFV), mobile edge computing (MEC) and fog computing (Fog Computing) and other technologies. In the field of spectrum, the EU’s 5G public-private partnership vision will also delineate hundreds of megahertz to improve network performance, and frequency bands of 60 GHz and higher will also be taken into account.
The EU's 5G network will be operational between 2020 and 2025.
On September 7, 2015, U.S. mobile operator Verizon Wireless announced that it will begin trials of 5G networks in 2016 and will be fully commercialized in some US cities in 2017. 
China's 5G technology research and development trials will be carried out in 2016-2018 and will be divided into three phases: 5G key technology trials, 5G technical program verification, and 5G system verification. 
In March 2016, Chen Xiongxiong, Vice Minister of the Ministry of Industry and Information Technology, stated that 5G is the main direction for the development of next-generation mobile communications technologies and an important part of the next generation of information infrastructure. Compared with 4G, it will not only further enhance the user's network experience, but will also meet the future application requirements of the Internet of Everything.
From the perspective of user experience, 5G has a higher speed and a wider bandwidth. It is expected that the 5G speed will increase by about 10 times than 4G, and only a few seconds will be required to download a high-definition movie that can meet consumers' demands on virtual reality and super. High-definition video and other higher network experience requirements.
From the perspective of industry applications, 5G has higher reliability, lower delay, can meet the specific needs of smart manufacturing, autopilot and other industrial applications, expand the development space of the integrated industry, and support economic and social innovation and development.
Looking at the development trend, 5G is still in the research stage of technical standards. In the coming years, 4G will maintain its dominant position and achieve sustained high-speed development. However, 5G is expected to be commercially available in 2020. 
Recently, Nokia and Canadian operator Bell Canada have cooperated to complete the testing of the first 5G network technology in Canada. The spectrum in the 73 GHz range was used in the test and the data transmission rate was 6 times that of the existing 4G network in Canada.
On February 9, 2017, 3GPP announced the official logo of "5G." 
On November 15, 2017, the Ministry of Industry and Information Technology released the “Notice on the Use of 3300-3600MHz and 4800-5000MHz Frequency Bands in 5th Generation Mobile Communication Systems” to determine the 5G IF spectrum, which can take into account the basic needs of system coverage and large capacity. 
In late November 2017, the Ministry of Industry and Information Technology of China issued a notice to formally initiate the third phase of the 5G technology R&D experiment and strive to achieve the basic objectives of the third phase of testing by the end of 2018. 
On December 21, 2017, at the 78th plenary session of the 3GPP RAN of the International Telecommunication Standardization Organization, the first version of the 5G NR was officially frozen and released. 
In December 2017, the National Development and Reform Commission issued the “Circular on Organizing and Implementing the Next-Generation Information Infrastructure Construction Project in 2018” and requested that 5G-scale network pilots be launched in not less than 5 cities in 2018. The number of 5G base stations in each city is quite large. There are no less than 500 full-network 5G terminals. 
On February 23, 2018, on the eve of the World Mobile Communications Conference, Vodafone and Huawei announced that the two companies have cooperated in Spain to complete the world's first 5G call test using the non-independent 3GPP 5G new wireless standard and Sub6 GHz frequency band. 
On February 27, 2018, Huawei released the first 3GPP standard 5G commercial chips Baron 5G01 and 5G commercial terminals at the MWC2018 exhibition, supporting the global mainstream 5G frequency bands, including Sub6GHz (low frequency) and mmWave (high frequency), theoretically. Achieve up to 2.3Gbps data download rate. 
Ultra-dense heterogeneous network
In the future, 5G networks are moving toward diversification, broadbandization, integration, and intelligence. With the proliferation of smart terminals, mobile data traffic will explode in 2020 and beyond. In the future 5G networks, reducing the cell radius and increasing the number of low-power nodes is one of the core technologies that guarantee the future 5G network to support 1,000-time traffic growth. Therefore, the ultra-dense heterogeneous network becomes the key technology for improving data traffic in future 5G networks .
In the future, wireless networks will deploy more than 10 times more wireless nodes than existing sites. Within the coverage area of the macro stations, the distance between sites will be maintained within 10 m, and 25 000 users will be supported within every 1 km2. At the same time, there may be a phenomenon that the ratio of the number of active users to the number of sites reaches 1:1, that is, there is a one-to-one correspondence between users and service nodes. The intensively deployed network narrows the distance between the terminal and the node, greatly improving the power and spectrum efficiency of the network. It also expands the network coverage, expands the system capacity, and enhances the services in different access technologies and coverage areas. Inter-level flexibility. Although the ultra-dense heterogeneous network architecture has great development prospects in 5G, the reduction in the distance between nodes and the increasingly dense network deployment will make the network topology more complicated, and thus it is prone to incompatibility with the existing mobile communication systems. In the 5G mobile communication network, interference is a problem that must be solved. The main interferences in the network are: intra-frequency interference, shared spectrum resource interference, and interference between different coverage levels. The interference coordination algorithm of existing communication systems can only solve the problem of a single interference source. In a 5G network, the transmission loss of neighboring nodes generally has little difference, which will lead to similar strength of multiple interference sources, further deteriorating network performance and making It is difficult to cope with the coordination algorithm. In addition, due to the large differences in service and user requirements for QoS, 5G networks need to adopt a series of measures to ensure system performance. These are: implementation of different services in the network, coordination schemes between various nodes, choice of networks, And energy-saving configuration methods .
Accurate and effective perception of neighboring nodes is a prerequisite for achieving large-scale node collaboration. In an ultra-dense network, dense deployment leads to a sharp increase in the number of cell boundaries, coupled with irregular shapes, resulting in frequent and complicated handovers. In order to meet the mobility requirements, new handover algorithms are bound to emerge; in addition, dynamic network deployment technology is also the focus of research. Because the opening and closing of a large number of nodes deployed by a user is sudden and random, the network topology and interference have a wide range of dynamic changes; and the number of service users in each small station also easily leads to the spatial and temporal distribution of services. Severe dynamic changes .
In a traditional mobile communication network, network deployment and operation and maintenance are mainly done manually, which consumes a lot of human resources and increases operating costs. Moreover, network optimization is not ideal. In the future 5G networks, the challenges of deployment, operation and maintenance of the network will be faced. This is mainly due to the existence of various wireless access technologies in the network and the node coverage capabilities of the networks are all different. The relationship between them is complex. Therefore, the intelligentization of self-organizing networks (SONs) will become an indispensable key technology for 5G networks .
The key issues solved by the self-organizing network technology are the following two points: 1 Self-planning and self-configuration in the network deployment phase; 2 Self-optimization and self-healing in the network maintenance phase. Self-configuration means the configuration of newly added network nodes can be plug-and-play, with low cost and easy installation. The purpose of self-optimization is to reduce the workload of the service and achieve the effect of improving network quality and performance. The method is to perform self-optimization of parameters in the local eNB or network management through UE and eNB measurements. Self-healing means that the system can automatically detect problems, locate problems, and troubleshoot, greatly reducing maintenance costs and avoiding the impact on network quality and user experience. The purpose of the self-planning is to dynamically perform network planning and execution, and at the same time meet the requirements of system capacity expansion, business monitoring, or optimization results. At present, there are mainly three types of self-organizing network architectures: centralized, distributed, and hybrid. Among them, the centralized architecture implemented based on the network management system has the advantages of wide control range and small collisions, but it also has the disadvantages of slow running speed and high complexity of the algorithm. In contrast, the distribution is just the opposite, and the distribution is implemented mainly through the eNB. , High efficiency and response speed, good network scalability, less laxity on the system, the disadvantage is the difficulty of coordination; hybrid combination of the advantages of centralized and distributed two kinds of architecture, the disadvantage is that the design is complex. When SON technology is applied to mobile communication networks, its advantages are reflected in the efficiency and maintenance of the network, and at the same time it reduces the capital expenditures and operating costs of the operators. Because existing SON technologies are based on their respective networks, operations such as self-deployment, self-configuration, self-optimization, and self-healing are independent and closed, and there is a lack of collaboration among multiple networks. Therefore, it is of far-reaching significance to study SON technology that supports heterogeneous network collaboration .
Content distribution network
In the future 5G, services such as audio, video, and graphics for large-scale users will grow rapidly, and the explosive growth of network traffic will greatly affect the quality of service for users accessing the Internet. How to effectively distribute large-volume service content and reduce the time delay for users to obtain information has become a major problem for network operators and content providers. Reliance on increased bandwidth alone does not solve the problem. It is also affected by factors such as route blocking and delays in transmission, and processing power of web servers. These problems are closely related to the distance between user servers. The content distribution network (CDN) plays an important supporting role in the capacity and user access of future 5G networks .
The content distribution network is adding a new level in the traditional network, namely the intelligent virtual network. The CDN system comprehensively considers information such as the connection status, load status, and user distance of each node, and distributes the related content to the CDN proxy server close to the user, so that the user can obtain the necessary information nearby, so that the network congestion can be eased and the response time can be reduced.