What is 5G millimeter wave

In the 1980s, the first generation of mobile technology, 1G, gave birth to devices such as cell phones, which made voice calls possible; in the 1990s, 1G was upgraded to 2G, which made text messaging possible; wait a minute, 3G ushered in the era of the smartphone, which made it possible to access the Internet online; 4G spawned services such as short-form video, real-time streaming, and VoLTE high-definition voice calls; and 5G is the vehicle through which everything will be interconnected. carrier for everything interconnected.

From 2G, 3G, 4G to 5G, there has been a gradual increase in the size and height of the frequency bands. As the frequency increases, the band gets wider.

So the question is, how does 5G provide such fast speeds?

What is millimeter wave?

Theoretically,what is a distinguishing feature of 5g mmwave the simplest and crudest way to increase 5G network speed is to increase the frequency. Since the frequency bands below 5GHz are now congested and there are no new bands available, manufacturers have come up with millimeter wave technology.

Millimeter wave technology refers to electromagnetic waves with different wavelengths of 1-10 millimeters and frequencies between 30-300Ghz. According to the principle of data communication system, the maximum output signal for wireless network communication to carry out the bandwidth is the carrier through the frequency of about 5%, so for the carrier frequency is getting higher and higher, the signal processing bandwidth problem also affects more and more. In the millimeter wave band, 5G uses the band work is generally 28GHz and 60Ghz, 28Ghz available spectrum analysis bandwidth is 1Ghz, while 60Ghz is 2Ghz.

The 4g-LTE band has a maximum carrier frequency of about 2ghz and a bandwidth of 100mhz. using millimeter-wave technology, the bandwidth can be increased by a factor of 10, or 1,000 megahertz, and the transmission rate can be doubled.

But the speed of light = wavelength × frequency, the higher the frequency, the shorter the wavelength, so the millimeter wave signal attenuation is large. Millimeter waves are mainly affected by oxygen, humidity, fog and rain during atmospheric propagation.

Different millimeter wave bands are affected differently by oxygen, for example: 60ghz must withstand about 20db/km oxygen absorption loss; in high temperature and high humidity environment, millimeter wave signal can be reduced by half within 1 km; millimeter wave signal will also be attenuated when it passes through the fog and clouds,qcm6490 and the most obvious attenuation is in rainy days, when the transmission loss reaches 18.4 db/km.

Second, millimeter waves are easily blocked. Not only will they be blocked by buildings, they will also be blocked by the human body, even when you are holding a cell phone.

That's why we're using more low and medium frequencies for 5G at this stage. But the network speed can realize the enterprise breakthrough, increase the working frequency is inevitable in order to avoid the method. However, it is possible to increase the density of a base station by miniaturizing the 5G base station at the same time, as a way to effectively control the attenuation and obstruction of millimeter waves.

This utility model can replace a large base station, and if the signal is blocked when connecting to a large base station, the phone will automatically switch to a small base station, thus ensuring the stability of the signal connection.

Of course, the 5G program is not only millimeter wave, but also sub-6GHz. millimeter wave is widely used abroad, and the domestic choice is below 6GHz. So what is sub-6GHz and what is the difference between it and millimeter waves?

Millimeter wave is different from sub-6GHz

Sub-6GHz refers to the frequency band below 6GHz, including 800MHz, 900MHz, 1.8GHz, 2.1GHz, 2.6GHz, 3.5GHz and 4.9GHz, which is currently the golden frequency band for mobile communications, supporting medium and high-speed mobility, with low transmission loss, basically no rain fading, and support for non-linear-range wireless communications (NLOS).

The millimeter wave band is at 28GHz, 36GHz, 60GHz, etc. The characteristics that sub-6 has, it does not have, and it can be mainly used for enterprise fixed wireless network communication.

In terms of capacity, millimeter-wave bands can maximize the advantages of massive MIMO technology (the higher the frequency, the smaller the antenna array size, the easier it is to achieve massive antenna arrays), however, developing RF devices in millimeter-wave bands is difficult and expensive.

On the contrary, frequency bands below 6 GHz can reduce the number of antennas to reduce the size of antennas, which is favorable for integration and RF devices are relatively mature. Overall, the technology in the sub-6GHz band is more mature and has a wider application market than the mmWave millimeter wave band.

There is no doubt that millimeter wave is the key technology for 5G to achieve maximum performance. Considering the cost and difficulty of development, below 6GHz is a good technology transition for now. In the future, millimeter waves may replace sub-6 GHz as the best 5G solution.

If millimeter waves are the best solution for 5G, why aren't they used domestically?

Domestic enterprises why we did not use millimeter wave?

First of all, there is the problem of the construction cost of millimeter wave. As we all know, nowadays, if the five ~ G network adopts SA network, then every one hundred and fifty meters or so have to build a base station, but if millimeter wave is used, then you need to build a base station every fifty meters or so. Therefore, the cost of building 5G base stations will increase the operator. In addition, millimeter wave itself is a high-frequency radio wave. Compared with ordinary base stations, power consumption will also be higher, and the combination of the two will make 5G electricity prices rise.

In addition, the penetration of millimeter waves is poor. Previously, Qualcomm specifically demonstrated the penetration of millimeter waves, and a person can block the transmission of millimeter waves with only one hand. This is somewhat similar to the two frequency bands of WiFi. 2.4GHz WiFi has strong penetration and wide coverage, but poor transmission rates, while 5GHz WiFi is just the opposite.

What does millimeter wave offer consumers?

Millimeter waves not only provide faster internet speeds, but have also spawned many applications that provide innovation for consumers and businesses, including industrial automation, telemedicine, autonomous driving, and more.

The low latency and ultra-fast transmission data rates of millimeter waves can make possible many things that businesses cannot carry out to achieve, such as: doctors we can choose to operate on patients far away by using tele-education healthcare service equipment, while at the same time, using China always keep a connection of telemetry sensors and wearable devices to make preventive medicine information safer and more reliable; self-driving cars with the 5G millimeter wave technology research, relying on the cloud server communication, to form a social public traffic management network; robotics companies can learn to become a new workforce, replacing humans to complete the time a lot of national work; do not need to spend a lot of money to buy a computer to get a good performance, cell phone users can be directly through the 5G network, connecting to the cloud, to become a portable handheld computer and so on.

5G millimeter wave technology

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