With the development of science and technology, the speed of mobile devices is getting faster and faster. In recent years, 5G technology is very popular. Many people may not know what it is, but they all understand that this represents a network speed upgrade. 5G network can let Our individual users enjoy a gigabit high-bandwidth experience. In theory, 5G can provide a maximum download experience of 20Gbps. In addition to 5G,
also has a very important technology, that is WiFi. It can be said that many families now have it. It can be regarded as the second brother of mobile communication. It has a complementary relationship with cellular networks, and a careful person will find a problem, that is WiFi also has 5G, not only 5G, but also 6G, so what do 5GWiFi and 6GWiFi refer to?
First of all, this is completely different from what we often say about 5G. The 5G we talk about daily refers to the fifth-generation mobile communication network, which is a wide area network, and WiFi belongs to a local area network. WiFi is of course iterated. The latest standard is WiFi 6, also called 802.11.ax, so AX routers of major brands on the market support WiFi 6, and AC routers are WiFi 5.
And 5G WiFi refers to WiFi in the 5GHz frequency band, why use the 5GHz frequency band? There is a very important thing involved here, spectrum resources, communication needs to use electromagnetic waves, but in order to avoid interference between different scenarios, electromagnetic waves are divided into many sections, and the right to use each section needs to be applied for.
WiFi is honored to be assigned to the 2.4GHz frequency band, and it has been used for many years, including the latest WiFi6 standard still has the 2.4GHz frequency band, and will always be used, and the 2.4GHz frequency band bandwidth is very narrow, probably Between 2.4GHz-2.48GHz, there is actually only a total of 80MHz bandwidth, and this bandwidth is divided into 14 5MHz frequency bands, and the actual use is 20MHz, so there are only three channels that interfere with each other completely independently. The transmission rate is only 2Mbps.
This means that a WiFi router can only satisfy three devices to surf the Internet at the same time and there is no frequency band interference. At the beginning, the 20MHz frequency band must meet the demand, but with the advancement of technology, our personal users have higher requirements for network speed, and the 20MHz bandwidth is no longer enough. For example, the current 5G and Sub 6GHz are all 100MHz frequency bands. The frequency bands from 2.4GHz to 5GHz are basically allocated to mobile communication networks, such as 3G, 4G, and many current 5G networks also use this range of frequency bands.
and above 5GHz can be said to be a very blank area with a large area of available spectrum resources, so the spectrum resources in this interval are selected for WiFi use, and the approximate range is between 5.1GHz-5.8GHz, that is A total of 700MHz frequency band, so the bandwidth is much larger. If 20MHz is divided, 15 independent frequency bands can be divided. If higher network speed is required, higher bandwidth can be allocated, such as 40MHz or even 80MHz. In this way, the speed is greatly improved!
With technological innovation, some mobile communication technologies, such as orthogonal frequency multiple access technology, and spatial multiplexing technology have also been used on WiFi. Simply put, a router will connect many devices at the same time, but different devices For different bandwidth requirements, sometimes low network requirements may occupy a lot of bandwidth, so you need to allocate resources to the terminal reasonably. For example, if your mobile phone has download tasks, then you can divide other idle bandwidth to the mobile phone.
The previous generation of WiFi 5 technology can achieve a bandwidth of 80MHz, and the final download rate can also reach the gigabit level. The current routers actually have two frequency bands, 2.4GHz and 5GHz, 2.4GHz coverage is wide, 5GHz network speed is high , But slowly people find that the 5GHz frequency band is not enough, because people are beginning to consider increasing the communication bandwidth to 160MHz, and between 5.1GHz-5.8GHz, if it is divided into 160Hz frequency bands, it will not be divided at all. Through carrier aggregation That is, four 40MHz carriers must be allocated at the same time, which means that one user has to occupyChannels for 4 users.
can only continue to increase the frequency, so the 6GHz frequency band is allocated to WiFi, which is roughly in the range of 5.9-6.1GHz, which is about the total bandwidth of 1.2GHz, which can be divided into 15 80MHz spectrums, and even allows direct use of a single With a bandwidth of 160Hz, the transmission rate will double again. Theoretically, the transmission rate is 2400Mbps, which can be even higher through carrier aggregation, and can allow simultaneous superimposed transmission with 2.4GHz and 5GHz frequency bands.
Currently, Qualcomm has provided relevant technical solutions, that is, WiFi 6E, which appeared on the 865 Plus. Although it still belongs to the WiFi 6, it has expanded the frequency band to the 6GHz area, that is, 6G WiFi. In the future, WiFi 6 routers or WiFi 7 routers will become tri-band (2.4GHz, 5GHz, 6GHz), but 6G WiFi seems to be very active in the United States, and tests are already underway, and there seems to be no such strong enthusiasm in China. .
In addition, WiFi 6 actually provides a 60GHz millimeter wave communication solution, but we can clearly feel the signal attenuation and wall penetration performance in the 5GHz frequency band. Although the millimeter wave WiFi solution looks very good, after all There are more bandwidth resources, that is, a single bandwidth of 400MHz, or even 800MHz, can be very fast, but the transmission capacity will be very weak. A router may be needed in a room, so the cost will be high, but millimeter wave communication Technology will certainly be gradually applied in the future.
