As a kind of radio wave, the millimeter wave in the past was inconspicuous in the past. Compared with its lower frequency microwave, the transmission distance is farther, and it has great achievements in the field of communication. There are millimeter waves in the middle that no one cares about.

However, at some point, mmWave suddenly became the focus of everyone's attention.

The popular fried chicken on the tuyere

If you want to talk about what the air outlets are in today's era, I believe everyone will blurt out terms such as 5G, autonomous driving, artificial intelligence, etc. What is not well-known to the public is that these outlets use a technology called "millimeter wave".

From this, it can be seen that this "wave" called millimeter wave is a tuyere in the tuyere, and it is difficult to think whether it is popular or not.

Millimeter waves generally refer to electromagnetic waves with a wavelength of 1-10 mm. Millimeter waves have extremely high bandwidth, and the total available bandwidth is as high as 135GHz, which is five times the bandwidth of traditional microwave bands. force;

Secondly, the beam of the millimeter wave is very narrow, which can more accurately distinguish the target and restore the details of the target;

Compared with lasers, millimeter waves have lower climate requirements. Compared with microwaves, millimeter wave components are smaller in size, and millimeter wave devices are easier to miniaturize.

However, millimeter waves also have the disadvantages of severe attenuation and high requirements for device precision. It is these two shortcomings that have restricted the development of millimeter waves in the past.

Millimeter wave, the second half of the 5G equipment competition

The global 5G network frequency band is divided into Sub-6GHz and millimeter wave, and my country has put the 5G millimeter wave network construction on the agenda when the 5G Sub-6GHz network construction is basically mature.

Some people may have doubts, since both Sub-6GHz and millimeter wave can realize 5G, and Sub-6GHz is mature, why is it necessary to build millimeter wave?

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In fact, millimeter wave and Sub-6GHz can form a complementary relationship. The frequency band of 5G millimeter wave is 24GHz-86GHz, which is about 16 times that of Sub-6GHz frequency band, so the transmission speed and content will be much faster; also because of the high frequency band, 5G The propagation range of mmWave is also much smaller than that of Sub-6GHz.

Therefore, 5G millimeter wave is suitable for use in the same area, at the same time, and a large number of users such as stations, airports, and stadiums, while Sub-6GHz is suitable for use in long-distance and open places.

Whoever is the first to complete the 5G millimeter wave construction will be able to provide users with faster and more stable Internet services, and will win the second half of the 5G competition.

Autonomous driving, millimeter wave radar shows its talents

People have predicted that the Internet will be followed by the Internet of Things era, and millimeter-wave radar is the "ears" and "eyes" of the Internet of Things era. It has rich application prospects in many fields such as border defense, agriculture, and medical care. Among them, the most popular is the application in the field of unmanned driving.

The millimeter wave radar, like ordinary radar, sends out radio waves, then receives the echoes, and measures the position data of the target according to the time difference between sending and receiving.

Millimeter waves can help the car accurately perceive the surrounding environment, and quickly identify the distance, angle, speed and other data of the surrounding objects and the car, so as to ensure the safe driving of the car.

And because millimeter waves are less affected by bad weather such as rain, snow, and haze, millimeter waves can operate around the clock and have high stability, making them the best choice for IoT devices such as autonomous driving.

Wireless screen projection, the most perceptible scene at present

Perhaps the changes in the 5G band are difficult to perceive, and autonomous driving is too far away. Currently, it is still living in a sci-fi movie, and wireless projection is an application and technology that is closer to us.

The recently emerging millimeter wave wireless screen projector effectively solves the problem of video and audio air-dropping.

The traditional Wi-Fi screen projection and LAN screen projection have high latency, unclear picture quality, and intermittent signals, which are only "usable", and the millimeter wave wireless screen projection device can replace HDMI to a certain extent. The data cable meets the requirements of smooth office use.

Taking Greenlink's "Nebula Watcher" as an example, it adopts 60GHz millimeter wave transmission, the rate reaches 3.96Gbps, and the transmission speed reaches 480MB/s, which is equivalent to the transmission speed of USB3.0 and HDMI 1.0.

Thanks to the advantages of strong anti-interference ability of millimeter wave, it can also transmit 4K@30Hz pictures stably in large conferences and confined places, and the flexibility of use is enhanced after getting rid of the shackles of cables.

Although it is not widely used yet, as the public's requirements for picture quality are getting higher and higher, and the usage scenarios are becoming more random and complex, millimeter-wave wireless screen projectors will also have a wider space for use.

From: Blockchain Talk