What is Millimeter Wave? What is mmWave? What are the applications?

Electromagnetic waves with a wavelength of 1 10 mm.

Called millimeter wave, it is located in the wavelength range where microwave and far-infrared wave overlap, so it has the characteristics of both spectrums. The theory and technology of millimeter waves are the extension of microwaves to high frequencies and the development of light waves to low frequencies, respectively.

The mmWave band is not too precisely defined, and is usually in the frequency domain of 30 to 300 GHz.

The wavelength of 1 10 mm) electromagnetic waves are called millimeter waves, which are located in the wavelength range where microwaves and far-infrared waves overlap, so they have the characteristics of both spectrums. The theory and technology of millimeter waves are the extension of microwaves to high frequencies and the development of light waves to low frequencies, respectively.

People with very good hearing can hear very high audio, and usually children's ears are more sensitive than adults. So, maybe there are some sounds that you can hear, but Mom and Dad can't.

However, no matter how you say it, you won't hear all the sounds, and if it's really high, you won't be able to hear it. But dogs can! Dogs not only have good noses and a strong sense of smell, but also have excellent hearing.

There is a whistle that emits a high-pitched whistle, which is specially used to train dogs, and humans can't hear that whistle at all, but dogs can hear it, and they will obediently press the whistle to do the action. In short, there are many sounds in the world that cannot be heard by the ear. It's the same with light, there is a lot of light in the world that the eye can't see.

There are all kinds of colors that we can see, and among the light waves that can be sensed by the human eye, the longest wavelength is red light, in addition to orange, yellow, green, blue, indigo, violet, and so on; Of all the light waves that can be sensed by the human eye, the shortest wavelength is violet light.

Needless to say, there must be other colors that are not visible to the human eye, such as infrared (wavelength too long) and ultraviolet (wavelength too short), etc. Some animals can see colors that are invisible to these eyes, such as infrared light for snakes and ultraviolet light for bees.

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There are many other types of light waves (sometimes light waves are also called rays , so some people say X-rays, some say X-rays, both are the same). When you call your phone, you use airwaves. The dentist sees through your cheek and sees the teeth, the kind of ** that uses x-rays.

In addition, gamma rays, millimeter waves, submillimeter waves....These are different types of light that are invisible to the eye. The only thing we can see is the so-called visible light, but it's a pity! Human beings are like hearing-impaired friends who are appreciating **, and only part of what they can hear** is not enjoyed, and very low and high pitches cannot be enjoyed.

In short, there are various kinds of light emitted by stars, nebulae and galaxies, and the visible light in the universe can be seen with ordinary telescopes, but the study of other types of light can require special instruments. To find radio waves, millimeter waves, submillimeter waves, etc., astronomers use large antennas, which are commonly known as radio telescopes or radio wave antennas, which are usually shaped like shallow disks.

The ALMA Observatory, consisting of 66 radio telescopes, is designed to search for millimeter and sub-millimeter waves in the universe. This kind of millimeter-wave radio wave has a longer wavelength than infrared light, and of course the eye cannot see millimeter wave or sub-millimeter wave, but as long as there is a radio signal, ALMA will definitely be able to catch it. Ha!

Isn't that great? Because we must study millimeter waves and sub-millimeter waves, astronomers can better understand the universe, just observing visible light is not able to know the whole thing, such as the universe ** sugar molecules, this is by Alma from the radio signal to find, visible light can not help find sugar molecules!

In information communication, millimeter-wave communication is one of the focuses of current scientists' research.

Millimeter wave refers to a type of radio wave with a wavelength of only 1 10 millimeters. Millimeter-wave communication has incomparable advantages over other radio waves, such as microwave, shortwave, and mediumwave, so it is increasingly valued by the Institute of Information and Communications Technology and gradually applied in practice.

Millimeter wave is a very high-frequency electromagnetic wave, which is the only electromagnetic wave that can cover the oscillation frequency of human cells, with a wavelength of 1-10mm and an oscillation frequency of 30-300GHz

Radar is no stranger to everyone, not to mention the application of aircraft, ships, etc., in daily life, radar has gradually entered people's lives, through the integration of artificial intelligence technology, radar has become more "smart", smart wear, drones, car blind spot detection, etc. are all familiar applications.

Radar uses electromagnetic waves, which are alternating electromagnetic fields that propagate in free space, and the frequency of this electromagnetic field alternating determines the basic properties of radar. The radio bands used for AM and FM broadcasts are below 300 GHz, and the microwave bands are the main frequency bands used for communications and radar, where the 30-300 GHz frequency band is called millimeter wave.

Compared with optical seekers such as infrared, laser, and television, millimeter-wave seekers have strong ability to penetrate fog, smoke, and dust, and have the characteristics of all-weather (except heavy rain). In addition, the absolute accuracy, directionality, and stability of the millimeter wave seeker are also better than those of other microwave seekers.

Comparison of sensors.

The fusion of radar and millimeter wave, millimeter wave radar has become the vast power of Sun Dasheng, smart office, smart home, smart home appliances, amusement equipment, smart lighting, smart bathroom, transportation, security, nursing, etc., can see the powerful ability of millimeter wave radar.

Hello netizens, it's a pleasure to meet your question. In recent years, with the growth of demand for millimeter-wave systems, millimeter-wave technology has made major breakthroughs in the development of transmitters, receivers, antennas and millimeter-wave devices, and millimeter-wave radar has entered a new stage of various applications. Since the 80s of the 20th century, due to the growing demand for millimeter-wave radar, a boom in the development of millimeter-wave radar has formed, which depends on the following characteristics of millimeter-wave radar:

1) The frequency band is extremely wide, suitable for all kinds of broadband signal processing; 2) Narrow beams can be obtained under small antenna apertures, with good directionality, extremely high spatial resolution, and high tracking accuracy; 3) It has a wide Doppler band, the Doppler effect is obvious, it has good Doppler resolution, and the speed measurement accuracy is high; 4) The ground clutter and multipath effects have little influence, and the low-altitude tracking performance is good; 5) The millimeter wave scattering characteristics are sensitive to the details of the target shape, so it can improve the ability of multi-target resolution to identify the target and the imaging quality. 6) since millimeter-wave radars are emitted in narrow beams, making it difficult for the enemy to intercept them in electronic countermeasures; 7) At present, the stealth frequency range of stealth aircraft and other targets is limited to 1 20 GHz, and because the uneven parts such as the fuselage are more obvious than those of millimeter waves, these uneven parts will produce angular reflection, thereby increasing the effective reflection area, so millimeter wave radar has a certain anti-stealth function; 8) Compared to laser and infrared, although it does not have the higher resolution of the latter, millimeter wave has the ability to penetrate smoke, dust, and fog and works around the clock. The disadvantages of millimeter-wave radar are mainly affected by atmospheric attenuation and absorption, and the current range is mostly limited to less than 10 kilometers. In addition, compared with microwave radar, the components of millimeter-wave radar currently have a low yield rate for mass production.

In addition, many devices need to be coated with gold or silver in the mmWave band, so the cost of the device is high. Finally, I wish you a happy life.

Questions. What disease can be cured by the Bolai wave ** instrument, please give it to you.

The millimeter wave instrument is mainly used for all kinds of pain and cardiovascular and cerebrovascular diseases, in addition to the regulation of sub-healthy people and the treatment and recuperation of various chronic diseases. In fact, for millimeter wave meters, the focus is on understanding millimeter waves. The wavelength of millimeter wave is 1-10mm, which is exactly between microwave and infrared, and can completely act at the cellular level, so that millimeter wave and cell coherent resonance, so that the diseased cell can be adjusted so that it can be repaired, so as to achieve normal functional effect.

The popular millimeter wave instrument is to generate millimeter waves, so that the millimeter wave can no longer be seen from the macroscopic eye level, but directly reach the cell level of the corresponding organ, so the role of the millimeter wave instrument is obvious.

Questions. How much does it cost?

Hello netizens, after inquiring about this millimeter wave ** instrument, the national price is about 12,800 yuan.

Questions. Can he cure the disease?

Hello netizens, I'm sorry. To tell you the truth, healing is not my specialty. You'll have to go to the hospital.

Millimeter Wave. Refers to electromagnetic waves with a wavelength of 10 1 mm. It is located in the wavelength range where microwaves and far-infrared waves overlap, so there are both.

Spectrum. features: Millimeter wave in communications, radar, guidance, remote sensing technology.

Radio astronomy.

Clinical Medicine and.

Spectroscopy. are of great significance.

It can be applied to mobile phones, but it will not be popularized because it is not used in China, and it has been popularized in some foreign regions, and millimeter wave is the main frequency band used in the United States, which is characterized by fast transmission speed, but poor penetration. Millimeter waves are electromagnetic waves with a wavelength between 1 millimeter and 10 millimeters, and we know from physics classes that the higher the frequency of electromagnetic waves, the shorter the wavelength, and the worse their penetration.

Sub-6GHz and mmWave represent two large ranges of 5G wireless frequencies. At present, China's 5G construction is dominated by Sub-6GHz, while the United States is dominated by millimeter waves, which are also the two directions of global 5G development.

The current state of mmWave applications.

At this stage, China has chosen the sub-6GHz frequency band to develop 5G, the United States mainly chooses the millimeter wave frequency band, and South Korea, Japan, Europe and other countries or regions are developing both frequency bands. Sub-6GHz and mmWave are complementary, not iterative. Just like data cellular networks and Wi-Fi, network construction depends on the specific needs of the operator and the usage environment.

First, the advantages are different.

1. Centimeter wave: It can take into account the coverage of the network and the penetration ability of the building.

2. Millimeter wave: extremely wide bandwidth, it is generally considered that the frequency range of millimeter wave is as high as the bandwidth; The beam is narrow, and the beam of millimeter wave is much narrower than that of microwave under the same antenna size; The propagation of millimeter waves is much less affected by the climate and can be considered to have all-weather characteristics.

Second, the disadvantages are different.

1. Centimeter wave: The centimeter wave in the sub-6 frequency band in the United States has always been occupied by the military, resulting in the United States having to use millimeter wave to build 5G networks.

2. Millimeter wave: severe propagation attenuation in the atmosphere; The processing accuracy of the device is required.

Third, the wavelength is different.

1. Centimeter wave: Usually centimeter wave refers to electromagnetic waves in the frequency domain of 3 30GHz (wavelength of 1 10cm).

2. Millimeter wave: The electromagnetic wave with a wavelength of 1 10 mm is called millimeter wave, which is located in the wavelength range where microwave and far-infrared wave overlap.

1. The nature is different.

Millimeter waves are located in the overlapping range of microwave and far-infrared wavelengths, so they have the characteristics of both spectrums. The theory and technology of millimeter waves is the extension of microwaves to high frequencies and the development of light waves to low frequencies.

The basic properties of microwaves are penetration, reflection, and absorption. In the case of glass, plastic, and porcelain, microwaves are almost passed through without being absorbed. Water and food, etc., absorb microwaves and cause their own heat. Metals, on the other hand, reflect microwaves.

2. The characteristics are different.

The millimeter wave frequency range is generally considered to be 26 5 300 GHz, with a bandwidth of up to 273 5 GHz. More than 10 times the total bandwidth from DC to microwave. Even if atmospheric absorption is taken into account, only four main windows can be used for propagation in the atmosphere, but the total bandwidth of these four windows can reach 135 GHz, which is five times the bandwidth of each frequency band below microwave.

In today's world of limited frequency resources, this is certainly attractive.

Microwaves have longer wavelengths than other electromagnetic waves used for radiative heating, such as infrared and far infrared, and therefore have better penetration. When the microwave penetrates the medium, the microwave interacts with the medium to a certain extent, and the microwave frequency is 2450MHz.

The dielectric molecules vibrate 2450 million times per second, the dielectric molecules rub against each other, causing the increase of the medium temperature, the internal and external heating of the dielectric material is almost at the same time, and the formation conditions of the bulk heat source greatly shorten the conditions of the thermal conductivity and dielectric loss factor of conventional heating and the negative correlation with the medium temperature, and the internal and external heating of the material is uniform.

3. The frequency and wavelength are different.

Electromagnetic waves with a wavelength of 1 10 millimeters are called millimeter waves.

The wavelength of the microwave is between 1 meter (excluding 1 meter) and 0 1.