FR1 defines 450mhz-6000mhz, which is also known as sub-6ghz.
FR2 is defined as 24250 mhz-52600 MHz. Since most of the bands covered by FR2 are less than 10 mm wavelength, this part of frequency band is also called millimeter wave.
The global 5g network frequency band is mainly divided into sub-6ghz and millimeter wave. At present, sub-6ghz is mainly used in China. The characteristics of this band are: strong signal penetration, but data transmission speed is slower than millimeter wave. Specifically speaking, the maximum downlink rate of chips supporting sub-6ghz is 4.7gbps, while that of chips supporting millimeter wave can reach 7.35gbps, which can even achieve high-speed transmission of 10Gbps in theory.
The United States mainly uses millimeter wave band, which is characterized by high transmission speed but poor penetration. How bad is that? Millimeter wave is an electromagnetic wave whose wavelength is between 1 mm and 10 mm. We can know from physics class that the higher the frequency of electromagnetic wave is, the shorter the wavelength is, the worse its penetration is.
In this regard, some foreign digital bloggers have tested 5g signals of T-Mobile and other operators in the United States. T-Mobile covers sub-6ghz and millimeter wave bands, while other operators mainly use millimeter wave band.
Millimeter wave penetration ability is poor, vulnerable to environmental impact
The results show that the 5g mobile phone with millimeter wave technology can be blocked by almost anything, such as telephone booth, glass, trees and rain, etc. as long as there is occlusion between the base station and the mobile phone, the 5g network may fall back to 4G state. In contrast, the carrier signals with sub-6ghz and MMW coverage at the same time perform better.
In short, sub-6ghz and millimeter wave represent two large ranges of 5g wireless frequency. At present, Chinas 5g construction is dominated by sub-6ghz, while the United States is dominated by millimeter wave, which is also the two directions of global 5g development.
Current status of sub-6ghz and millimeter wave applications
At present, China has chosen sub-6ghz frequency band for 5g development, while the United States mainly chooses millimeter wave frequency band, while South Korea, Japan, Europe and other countries or regions are developing both frequency bands. Sub-6ghz and millimeter wave are complementary rather than iterative. Just like data cellular network and Wi Fi, network construction depends on the specific needs of operators and use environment.
Network congestion is like a traffic jam. High bandwidth of millimeter wave can satisfy more people to get online at the same time
On the other hand, the bandwidth of millimeter wave is higher, it is easier to solve the congestion problem of users network, and at the same time, it can satisfy more people to access the Internet. The coverage area of this technology is relatively small, and it is more suitable for application in densely populated scenes such as stations, airports, stadiums and so on. In order to achieve the same coverage level as sub-6ghz, the density of the base station is at least five times that of the sub-6ghz base station, and the cost is naturally higher.
To take a simple example, millimeter wave not only needs more signal towers to cover, but also continuously outputs high-intensity signals. The output power of 5g base station is three times that of 4G, and power consumption alone is a huge expense. It is not difficult to understand that some time ago, China Unicom shut down 5g base stations at night in order to save power operation costs.
The cost is high and the signal coverage is easy to be restricted by the environment. Do American operators choose millimeter wave only because of the high speed?
At present, Chinas choice of sub-6ghz frequency band is mainly to solve the signal coverage problem of 5g network, and put 5g technology into practical application as soon as possible, so that most consumers can use 5g network. Of course, for the construction of millimeter wave, China has not stopped.
In March this year, the Ministry of industry and information technology issued the notice on promoting the accelerated development of 5g. It was mentioned in the question that timely release the frequency utilization planning of some 5g millimeter wave frequency band, organize and carry out millimeter wave equipment and performance testing, so as to make reserves for the commercial use of 5g millimeter wave technology, indicating that the state also advocates operators to prepare for the commercial use of millimeter wave, so as to facilitate the construction and development of 5g in the future.
Millimeter wave band width, low delay, high capacity characteristics, in daily life, can achieve second download blue video, solve network congestion. In particular, it can also realize remote control and telemedicine of industrial robots, and has a broad application prospect.
Write it at the end
At present, many mobile phones support 5g millimeter wave in hardware, but manufacturers will make corresponding adjustments according to the market situation in different countries. This also answers the question at the beginning of the article. This year, the Bank of China iPhone 12 may not support millimeter wave, because it is not necessary for apple and domestic operators to launch it. At this stage, consumers cant use it at all. Domestic millimeter wave is still a long way from being truly practical.
In addition, between the signal and the network speed, I believe most people are more concerned about the stability of the signal. After all, the 5g network speed of the sub-6ghz band in China is very fast, so we dont want to experience the fear of being dominated by the iPhone signal difference.
Whether the iPhone 12 supports millimeter wave 5g or sub-6ghz, Apple may launch iPhones that support different types of 5g spectrum according to the local 5g construction situation. Instead of guessing about these, users may be more concerned about when the price of 5g packages will come down, which is the key to the popularity of 5g.
In addition, for the price of iPhone 12, the price increase is inevitable because of the increased cost of 5g. However, we believe that the subsidy for domestic third-party e-commerce platforms will be large. For example, last year, when the iPhone 11 series was released, pinduoli even launched a 10 billion subsidy program, with subsidies ranging from 500 yuan to 900 yuan for new machines. For this years iPhone 12 pinduoduo will discount how much, we might as well look forward to.
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