Text: Wang Xinxi
A lot of controversy about the coming of the 5G era, WiFi may have to disappear. At the Guizhou Digital Expo, Lu Tingjie, a professor at Beijing University of Posts and Telecommunications, said that 5G will be the basis of 4k and 8k video in the future. wifi is already a backward technology and it is difficult to carry such a large bandwidth.
But in my opinion,WiFi will not be eliminated, but will evolve and evolve.
As early as 2017, Bloomberg had issued a document saying that the 5G era is coming to WiFi or will be out of the historical arena, pointing out that the current major mobile operators in the United States are providing unlimited data traffic services, consumers do not need to open WiFi networks to avoid expensive traffic charges. . This will likely cause WiFi to exit the stage of history.
We know that domestic expectations for 5G are great. Operators need to improve their performance and develop new services such as IoT, cloud and big data. These services are very compatible with the 5G era. Once the 5G network is officially commercialized, it is expected that 撬Animal networking industry.
Not long ago, the Ministry of Industry and Information Technology officially issued a 5G commercial license. China Mobile, China Telecom, China Unicom and China Radio and Television have all obtained the 5G license. At present, global 5G has entered the critical period of commercial deployment, and from the perspective of China's 5G commercial timetable, the 5G commercial timetable is roughly in 2020.
As we all know, 5G brings more Internet speed than the current 4G experience. It is said that 5G's network speed can reach 10-100 times that of 4G, can transmit 8K resolution 3D video in real time, or download a 3D movie in 6 seconds.
But the problem is that 5G commercial use in 2020 does not mean that the national 5G is completely seamlessly covered. It requires a relatively long construction period to gradually replace and cover it gradually.
According to the law, the existing 4G LTE will continue to evolve and become an important part of the 5G platform, and the 4G, 3G, and 2G networks will continue to work after 5G commercial use. and,The actual communication speed of 5G is subject to the external environment, including the number of devices and users and the coverage of base stations.
Of course, the advantage of 5G over WiFi is that its faster network speed and low latency have solved the delay of WiF's network transmission, as well as slow speed and weak security. However, WiFi also has advantages. First, its traffic is cheap. The use environment is more indoors and more stable; the second is the exclusive use of each other, and also bears a lot of data traffic scenarios.
Although the 5G network has a bright future, its short board is also very obvious. One is capacity. The terminal base station to which 5G is connected has a limited capacity. Once the capacity exceeds the limit, the user experience and speed will decrease, and the theoretical speed will not be reached. At present, each base station of the 4G network can accommodate up to 1200 users, and the 5G network is similar. If the number of people exceeds the limit, the network speed will fluctuate and decrease.
The second is weak penetration. Because the 5G network uses the millimeter wave technology, the 5G signal has a higher frequency than the 4G network. The 5G signal is weaker than the 4G's ability to “pass through the wall”.Because it is a kind of electromagnetic wave that has weak penetration and will decay rapidly, which determines its anti-interference ability is weak and its stability is not as good as WiFi.
The fourth is the low coverage of the base station, which means that the wide coverage of 5G requires more base stations to be built, which requires longer base station replacement work.
What is the coverage of 5G base stations? According to industry sources, the current coverage of the 5G pilot is weak. In the 2G era, a base station can cover more than 5 kilometers, and in the 4G era, a base station can cover only 1 to 3 kilometers, and in the 5G era, a 5G micro base station can only cover 100 meters to 300 meters. In addition, the 5G signal has poor penetrating power and is dropped when entering the building.
The reason why the coverage of the 5G base station is low is that the 5G uses a higher frequency band, the communication frequency is lower, the diffraction ability of the radio wave is stronger, and the high frequency can only rely on direct reflection and reflection, which will generate many dead angles. The 5G macro base station signal deployed in the high frequency band faces a large link loss problem when the indoor wall is penetrated, and the indoor depth coverage is limited.
simply put,The high frequency band has a short propagation radius, and the medium and low frequency bands have a long propagation radius, and the latter has a better coverage. Therefore, the coverage area of a 5G base station is naturally smaller than that of 4G.
The fifth is that the scarcity attribute of frequency resources contradicts the realization of unlimited traffic in the 5G era.
When it comes to the layout of the base station, we have to talk about frequency resources. In fact, as early as 2017, major operators began to test the unlimited traffic packages, allowing consumers to rekindle the hope of unlimited traffic. The reason why unlimited traffic is difficult to achieve is because wireless frequency resources are limited. Unlike fixed networks, wireless data transmission depends on bandwidth.
The frequency resources of each of the three major operators are precious resources, and the current one base station can withstand hundreds of megabytes of traffic, and the number of access users per base station is also limited. Users have more preferential access, which will affect all users. The speed of the Internet, therefore, the network quality of operators continues to decline as the number of users increases.
Today, the current demand for entertainment consumption is skyrocketing, the Internet access rate of 4G networks is getting faster and faster, and the contradiction of frequency resources is becoming more and more obvious. In the era of high-definition video and live broadcast, VR games, and short video, the increase in the size of unlimited traffic users will lead to a small number of frequency resources. When people occupy it, the traffic will reach tens of mega-hundreds of megabytes in an instant. If the unrestricted use is excessively released, the base station cannot afford it.
According to the arrangement of the Ministry of Industry and Information Technology, China Telecom obtained 5G test frequency resources with 100MHz bandwidth of 3400MHz-3500MHz; China Mobile obtained 5G test frequency resources of 2515MHz-2675MHz and 4800MHz-4900MHz bands; China Unicom obtained 5G test frequency of 3500MHz-3600MHz with 100MHz bandwidth Resources.
In the true sense, the unlimited traffic package needs to break the limitation of the limited frequency resources. It is difficult to say whether the 5G era can break through the technical bottleneck of wireless frequency scarcity. If the tariff is too high and the wireless traffic package is difficult to achieve, the status of Wi-Fi is still not Will be replaced.
The reason why WiFi will coexist with 5G networks for a long time is more than that. It also involves the competitiveness of WiFi's self-evolutionary upgrades.
First, even if 5G comes, the home Internet will not abandon the fiber and switch to 5G.
What needs to be known is that after the current fiber-optic network enters the home, the terminal and the device are connected through WiFi. The so-called WiFi is to convert the wired signal into a wireless signal, and the wireless wave is connected to the network, which cannot be separated from the stable bandwidth or the optical fiber. However, fiber-optic access is a long-term investment in the country and a network infrastructure that is being planned for expansion. It will not be abandoned in a short time.
Second,Technically, 5G is faster than 4G because of the higher frequency band, and WiFi is also being upgraded. In October 2018, the Wi-Fi Alliance has released a new Wi-Fi technology standard, Wi-Fi 6.The prospect of WiFi6 is not inferior to 5G.
By increasing the coding efficiency of data to increase the throughput of the transmission, WiFi6 also makes the data throughput larger and faster. The stability of the WiFi6 standard for practical applications and the low latency performance level with 5G may not be much more.
According to the industry, the new generation of WiFi standards is the standard of 802.11ax (also known as WiFi6). The first two generations of technology —— 802.11n and 802.11ac are named WiFi4 and WiFi5 respectively. Multi-user Multiple Input Multiple Output (MU-MIMO) and Orthogonal Frequency Division Multiple Access (OFDMA) have been added. These technologies enable WiFi6 to better serve multiple devices simultaneously.
According to the measured data of the first batch of 5G users in the United States, the current downlink speed of 5G network mobile phones is 400Mbps-600Mbps (equivalent to download speed 50— 60MB/s), while Huawei, the president of Huawei's terminal mobile phone product line, used Huawei MateX. The measured 5G download rate results in 1Gbps. However, there is a saying that Wi-Fi 6 is based on Wi-Fi 5 and is more suitable for processing large data requests at the same time, about three times the current maximum speed of Wi-Fi 5.
To some extent, in the 5G era, the speed of WiFi has also increased by one level, because WiFi will also be upgraded to 5 GHz, that is, WiFi also has a fifth-generation frequency band. There was an article on the IT Peer Network that said Wi-Fi 6 would increase the efficiency of a single network by a factor of about four, which in turn would increase the average data throughput of those connected to Wi-Fi 6 by about 4 Times.
In addition, it is revealed that the Wi-Fi6 standard absorbs a large number of 5G key technologies, such as OFDMA, MU-MIMO, 1024QAM, etc., to optimize the power consumption and coverage of the device, and is fully applicable to support various IoT applications of smart homes. The theoretical downlink speed of 5G is 10Gb/s, while the fastest downlink speed of WiFi6 is 9.6Gb/s.
In other words, WiFi6 has become more and more like 5G, and both are on the same level of speed.
Third, the most direct is the economic account.With regard to the speed and traffic that are generally worried about in the 5G era, there is a big increase in costs, and the advantage of free WiFi is obvious.
The 5G high-speed network era is an important time node for operators to increase traffic charges in order to improve their performance. Therefore, for 5G users, the bandwidth charges, large bandwidth consumption, and 5W era are more likely to bring additional power consumption. With the skyrocketing tariffs, many users have expressed concerns about the traffic charges in the 5G era. In addition, the market will face additional power consumption caused by the 5G-enabled terminal performance enhancement and how to implement multi-antenna design in a limited space.
Some users have said that many hardware devices, including your indoor TV, mobile phone, tablet, computer, etc., are connected through 5G network. How much will it cost per month? In the homes, because the performance of fiber and WiFi is rapidly improving and the cost is lower, there is basically no big pain point of experience. As long as the user is rational enough, he will not throw it away and choose to spend money to purchase the 5G flying base station.
Therefore, if the 5G tariffs skyrocket, it is clear that more traffic demand may be diverted to the WiFi network. Since 2009, China Mobile has invested heavily in building millions of WiFi hotspots nationwide. The launch of these WiFi hotspots has also played an important role in the shunting of mobile data networks.
Therefore, in summary,Compared with the past, WiFi is not marginalized, but has the possibility of rising, because in the past, WiFi applications were limited to the consumer Internet, but in the future it may open up the scene and application space of the industrial Internet.
For example, in the automotive industry, manufacturers are now disagreeing over whether Wi-Fi or 5G is the standard for car network communication. Although there are more manufacturers who agree to adopt the 5G standard, brands such as Renault, Toyota, and Volkswagen are supporting Wi-Fi, and the European Parliament supports Wi-Fi as the standard for network communication.
Even in terms of consumption scenarios, indoor space will be the natural dominant territory of Wi-Fi in the long run. The 5G layout rhythm, its base station construction popularity and base station coverage should be penetrated into the indoor private territory from the outdoor wide coverage. It is necessary to eliminate small networks through the big network. At present, it is a task that cannot be completed in a short time, and WiFi6 is obviously more competitive than in the past.
Although the evolution of new 5G technologies will affect WiFi in the future, wifi is also evolving, which determines that WiFi has a large market for high privacy (such as home indoors, shopping malls, and office areas). From this point of view, indoor WiFi is used as a supplement, and the outdoor 5G division of coverage will not change.
At present, I want to realize the Internet of Things, connect various smart devices to the network, and perhaps still have a wireless router with WiFi6 technology, which is difficult to be replaced as a “smart gateway”.
therefore,WiFi will not be eliminated, but will continue to evolve. 5G and WiFi have applications and imagination in the industrial Internet of Things. The two are not a substitute relationship, but a relationship of mutual promotion, competition and coexistence.
Therefore, 5G will come, WiFi will also evolve itself. Instead of questioning whether the 5G era will eliminate WiFi, it is better to think about the new opportunities that the WiFi6 era will bring.