A few days ago, the Ministry of Industry and Information Technology issued a document to allocate all or part of the 6GHz (6425-7125MHz) frequency band for 5G/6G systems, which has aroused widespread concern inside and outside the industry.

The 6GHz frequency band, to be precise, refers to the frequency range of 5925-7125MHz, with a total of 1200MHz spectrum resources.

6GHz and 6G technical standards are two different things. Many media say that 6G is coming soon, so the spectrum is allocated to 6G, blah blah blah. This is obviously nonsense, 6G is still very early, at least five years later.

In this frequency band division, it can only be said that the spectrum is allocated to cellular mobile communication technology (IMT, International Mobile Telecommunications, international mobile communication, 2G-6G belongs to this), and it is not clear that it must be used by 6G in the future. 5G can also be used first if needed.

Another camp corresponding to IMT is the RLAN (Radio Local Area Network, wireless local area network) technology represented by Wi-Fi.

In this spectrum division incident, simply put, the two camps of cellular communication and Wi-Fi competed for the spectrum, and the former won a phased victory.

Why grab the 6GHz frequency band?

For any wireless communication technology, the most important thing is spectrum resources.

For IMT cellular communication, I posted a spectrum distribution map ( link ) a few days ago. The spectrum in use is mainly in a few ranges:

Below 1000MHz:

For example, 700MHz and 800MHz belong to the low-frequency band, and the working frequency is low, but the wavelength is longer and the coverage is farther. This kind of frequency band has extremely tight resources and is called the golden frequency band.

Its bandwidth is relatively narrow (1MHz/5MHz/10MHz, etc.), and it is not suitable for large-bandwidth (video, VR/AR, etc.) services, but it is very suitable for IoT such as NB-IoT, and it is cheaper to build a site.

1000MHz~7125MHz :

The so-called mid-frequency band is also the main frequency band of our mobile communications now. In 5G, we often refer to Sub-6GHz (meaning "below 6GHz", and later the range was changed to below 7125MHz), which mainly refers to this frequency band.

There are slightly more resources in this frequency band, and each operator can be allocated several hundred MHz. Using this frequency band for coverage, the area is moderate, and it can achieve large bandwidth and large capacity, which belongs to balance.

Above 24.25Ghz:

This is the millimeter wave frequency band that the industry often refers to. The coverage capability is weak, but the bandwidth is large, the rate is high, and the capacity is large.

The frequency band a little higher than the millimeter wave frequency is the THz (terahertz, 1T is 1000G) frequency band, which was previously considered to be the research direction of the 6G standard.

Let’s look at Wi-Fi again.

The frequency bands used by Wi-Fi are simpler. It uses unlicensed spectrum, or what we call free spectrum. These spectrums, to put it bluntly, are left over from other people's use.

When I introduced the history of Wi-Fi before, I said that the major forces competed for spectrum. Some people say that some spectrum should always be reserved for small devices, free for ordinary users to do experiments and so on. Therefore, it was just a tiger's mouth, and there was an ISM (Industrial Scientific Medical, industrial, scientific, medical) frequency band. Based on this free frequency band, there was later Wi-Fi.

The traditional frequency band of Wi-Fi has two ranges, namely 2.4GHz and 5GHz. Everyone should be familiar with it.

Starting from Wi-Fi 6E, in order to obtain greater bandwidth, the idea of ​​using the 6GHz frequency band has been proposed and proposed to be used for Wi-Fi.

This is where the scramble for 6GHz comes in.

Everyone should remember that the 6GHz frequency band is very, very, very important.

For IMT cellular mobile communications, don't think about the low frequency band. In the middle frequency band, the 6GHz frequency band is the last piece of fat. It has the advantages of both coverage and capacity, which is conducive to the construction of high-quality cellular communication networks.

Although there are many resources in the millimeter wave frequency band, the frequency is too high and the coverage effect is not good. It has been used in some places abroad, and the general feedback is that it is not good. Some countries even took back the frequency bands. In our country, we have been suppressing it all the time.

6GHz, which plays a great role in the construction of 5G private networks in the industry, as well as in large-capacity demand scenarios such as gymnasiums. Also, 6GHz is an excellent resource for FWA scenarios.

For Wi-Fi, if the 6GHz frequency band resources cannot be obtained, the communication rate cannot be greatly improved, and its future prospects will be worrying. (With 6GHz, up to 29 40MHz channels can be added, 160MHz channels or 320MHz channels can also be easily realized, and the rate is directly doubled, which is really delicious.)

 What does this incident mean?

The competition around 6GHz has already started a few years ago.

There are different attitudes in different regions of the world, which can be roughly divided into several types:

1. All to Wi-Fi. Such as the United States, South Korea.

2. Half for Wi-Fi and half for IMT (or to be determined). Most of these. It should be noted that most of them use 500MHz of the low 6GHz frequency band (5925-6425MHz) for Wi-Fi, such as the European Union, Australia, and Japan.

3. All to IMT. Very few people hold this attitude.

China's attitude has always been rather vague. There used to be a lot of rumors that China would use all of IMT.

Some people think that it is because our country tends to state-owned enterprises, and operators are all state-owned enterprises, so it is only given to operators.

This statement is not quite right. The national conditions of our country are indeed relatively strong infrastructure. Our number of base stations is the largest in the world, and the coverage rate is also very high. The unified management of resources also serves the public and will have a higher utilization rate.

Another key point is that in the field of IMT, our country's industrial chain accounts for a higher proportion and has a greater say in technology. There are several big manufacturers in the IMT camp in the EU, so they also tend to give at least half to IMT.

As for the technical direction of Wi-Fi, basically the right to speak is in the hands of a certain country, and the control of the industrial chain accounts for a larger proportion.

If you still remember the battle between LTE and WiMAX, you should understand the truth.

China's division of 6425-7125MHz into 5G/6G this time is not just an internal matter of our country.

China is a country with a huge user base and industrial chain. Every decision we make in the field of communications has a major impact on the global communications industry.

The research and development of wireless devices all follow the wireless spectrum. For example, your research and development of 700M base stations is different from the development of 3.5GHz base stations. It’s not that if I build a base station, if I want to adjust 700M, I can use 700M, and if I want to adjust 3.5G, I can use 3.5G. New frequency bands require corresponding design, development and testing.

Using 6425-7125MHz for IMT means that industry chain manufacturers (including chip modules) will carry out industrial design and manufacturing based on this purpose. The industrial ecology on the Wi-Fi side will be damaged.

Therefore, the forces of IMT and RLAN will come to seek support from the Chinese government.

China's decision this time is a blow to the Wi-Fi camp. However, for them, it was also expected. In a sense, it's even good news.

why?

Because it was said before that all 6GHz should be given to IMT. This time it is publicly announced that half will be given first. Doesn’t that mean that for the remaining half, Wi-Fi still has a chance! It's better than declaring everything to IMT.

There is one more detail. According to Xiaozao Jun’s secret source, Kevin Robinson, chairman of the Wi-Fi Alliance, just visited the Ministry of Industry and Information Technology some time ago. Shortly after the visit, the Ministry of Industry and Information Technology issued this document, and you can take a closer look at the relationship in it.

I personally think that 5925-6425MHz is very likely for Wi-Fi. In other words, we and the EU are likely to go together.

In any case, towards the end of the year, the ending will gradually become clear.

On November 20, 2023, the 2023 World Radiocommunication Conference (WRC-23) of the International Telecommunication Union will be held in the United Arab Emirates. At the meeting, the final fate of the 6GHz frequency band will be discussed and decided.

Let's wait patiently for a few more months!