Впервые кому-то удалось так просто и понятно объяснить принцип работы 5G.

1

Простая и волшебная формула

Today’s story starts with a formula.

It's a formula that's both simple and magical. It's simple because it only has 3 letters in total. It is said to be magical because this formula contains the profound secrets of communication technology, and countless people on this planet are obsessed with it.

Эта формула ——

I believe many students recognize this formula. If not, and you are a science student, please remember to call your middle school physics teacher when you have time!

Please explain, the above formula is the basic formula of physics.Speed ​​of light = wavelength & times; frequency.

For this formula, we can say:Whether it is 1G, 2G, 3G, or 4G or 5G, everything remains the same. They all make a fuss about it and do not jump out of its "Five Finger Mountain".

Let me tell you slowly.

2

wired? wireless?

Communication technology, no matter what black technology or white technology, in the final analysis, can be divided into two types——Wired communications and wireless communications.

When I talk to you on the phone, information and data are either transmitted in the air (invisible and intangible) or in physical objects (visible and tangible).

If it is transmitted on physical materials, it is wired communication, which basically uses copper wires and optical fiber cables, collectively called wired media.

When data is transmitted over wired media, the rate can reach very high values.

Taking optical fiber as an example, in the laboratory,The maximum speed of a single optical fiber has reached 26Tbps. . . It is 26,000 times that of traditional network cables. . .

оптоволокно

Проблема распространения сигнала по воздуху является узким местом мобильной связи.

The current mainstream mobile communication standard is 4G LTE, with a theoretical rate of only 150Mbps (excluding carrier aggregation). This is completely incomparable to wired.

Therefore, if 5G wants to achieve high end-to-end speeds, the focus is to break through the bottleneck of the wireless part.

3

Какая волшебная волна

Как всем известно, беспроводная связь использует электромагнитные волны. Радиоволны и световые волны — это электромагнитные волны.

Функциональные характеристики электромагнитных волн определяются их частотой.Electromagnetic waves of different frequencies have different properties and characteristics, and thus have different uses.

For example, high-frequency gamma rays are very lethal and can be used to treat tumors.

постоянная частота электромагнитных волн

We currently communicate primarily using air waves. Of course, light wave communications are also on the rise, such as LiFi.

LiFi（Light Fidelity），可见光通信

Не отвлекаясь от темы, давайте сначала вернемся к радиоволнам.

Radio waves are a type of electromagnetic waves, and their frequency resources are limited.

In order to avoid interference and conflicts, we further divide the lanes on the radio wave highway and assign them to different objects and uses.

Применение радиоволн на разных частотах

Please pay attention to the red font in the picture above. Until now, we have mainly usedMedium frequency to ultra high frequency are used for mobile phone communication.

For example, the often mentioned "GSM900" and "CDMA800" actually refer to GSM operating in the 900MHz frequency band and CDMA operating in the 800MHz frequency band.

The current global mainstream 4G LTE technical standard belongs toУВЧ и УВЧ.

В нашей стране в основном используются УВЧ:

As you can see, with the development of 1G, 2G, 3G, and 4G, the frequency of radio waves used is getting higher and higher.

Почему это?

Это в основном потому, что,Чем выше частота, тем богаче частотные ресурсы, которые можно использовать.Чем богаче частотный диапазон, тем выше может быть достигнута скорость передачи данных.

Более высокая частота → больше ресурсов → более высокая скорость

It shouldn’t be difficult to understand, right? Frequency resources are like carriages. The higher the frequency, the more carriages there are and the more information can be loaded in the same time.

Итак, какая именно частота используется в сетях 5G?

Как показано ниже:

The frequency range of 5G is divided into two types: one is below 6GHz, which is not much different from our current 2/3/4G. There is another kind, which is very high.Выше 24 ГГц.

Currently, internationally, it is mainly used 28GHz Проведите эксперименты (этот частотный диапазон также может стать первым коммерческим частотным диапазоном для 5G).

If calculated based on 28GHz, according to the formula we mentioned above:

Okay, this is the first technical feature of 5G——

4

миллиметровая волна

Позвольте мне еще раз опубликовать таблицу сравнения частот:

Пожалуйста, обратите внимание на нижнюю строку. Это «миллиметровая волна»?

Давай, давай!

Okay, since high frequency is so good, you will definitely ask:"Why didn't we use high frequencies before?"

The reason is simple - it's not that I don't want to use it, it's that I can't afford it.

The salient characteristics of electromagnetic waves: the higher the frequency, the shorter the wavelength, and the closer it is to linear propagation (the worse the diffraction ability).Чем выше частота, тем больше затухание в среде распространения.

Посмотрите на лазерную указку (длина волны около 635 нм). Излучаемый свет направлен прямо. Если его заблокировать, он не сможет пройти сквозь указку.

Looking at satellite communications and GPS navigation (wavelength is about 1cm), if there are obstructions, there will be no signal.

The big pot of a satellite must be calibrated to aim at the direction of the satellite, otherwise even a slight deviation will affect the signal quality.

If mobile communications use high frequency bands, then its biggest problem isThe transmission distance is greatly shortened and the coverage capability is greatly weakened.

covering the same area,The number of 5G base stations required will greatly exceed that of 4G.

What does the number of base stations mean? Money! Invest! The cost!

Чем ниже частота, тем дешевле будет строительство сети и тем благоприятнее будет конкуренция. Именно поэтому в последние годы China Telecom, China Mobile и China Unicom ведут ожесточенную борьбу за низкочастотные диапазоны.

Some frequency bands are even called——Золотая полоса.

This is why, in the 5G era, operators are desperately fighting against equipment manufacturers, hoping to reduce the price of base stations.

Therefore, based on the above reasons, in order to reduce the cost pressure on network construction under the premise of high frequency,5G должен найти новый выход.

Какие есть выходы?

First, there is the micro base station.

5

micro base station

There are two types of base stations, micro base stations and macro base stations. Just by looking at the names, you can tell that the micro base station is very small and the macro base station is very large!

Macro base station:

Common outdoors, build one to cover a large area

Микробазовая станция:

Doesn’t it look cool?

There are even smaller ones, as big as a palm

In fact, there are many micro base stations now, especially in urban areas and indoors, where they are often seen.

In the 5G era, there will be more micro base stations, which will be installed everywhere and can be seen almost everywhere.

You will definitely ask, will there be any impact on the human body if there are so many base stations around us?

Мой ответ — нет.

In fact, contrary to traditional understanding, in fact,The greater the number of base stations, the smaller the radiation!

Think about it, in winter, in a house with a group of people, is it better to have one high-power heater or several low-power heaters?

High power solution▼

Low power solution▼

Картина выше ясна с первого взгляда.The base station is small and low-power, which is good for everyone.If you only use one large base station, if it is close, the radiation will be large, but if it is far away, there will be no signal, which is not good.

6

Where did the antenna go?

Have you noticed that mobile phones used to have very long antennas, and early mobile phones also had small protruding antennas. Why do our mobile phones now have no antennas?

На самом деле, дело не в том, что нам не нужны антенны;The antenna got smaller.

В соответствии с характеристиками антенны, длина антенны должна быть пропорциональна длине волны, приблизительно в пределах от 1/10 до 1/4.

С течением времени частота связи наших мобильных телефонов постоянно увеличивается, длина волны сокращается, а антенны становятся все короче!

For millimeter wave communication, the antenna has also become millimeter level. . .

This means that the antenna can be inserted into the mobile phone, or even many antennas can be inserted. . .

This is the third biggest killer feature of 5G——

7

Ｍактивный MIMO

(Multi-antenna technology)

MIMO is "Multiple-Input Multiple-Output" (Multiple-Input Multiple-Output), multiple antennas transmit and multiple antennas receive.

В эпоху LTE у нас уже была технология MIMO, но количество антенн было небольшим. Её можно было назвать лишь младшей версией MIMO.

In the 5G era, MIMO technology continues to be developed, and now it has become an enhanced version of Massive MIMO (Massive: large-scale, massive).

There are multiple antennas packed into a mobile phone, not to mention a base station.

Раньше базовые станции имели всего несколько антенн:

В эпоху 5G количество антенн рассчитывается не по корню, а по "массиву"... "антеннному массиву"... На первый взгляд, это звучит как трипофобия...

Однако расстояние между антеннами не может быть слишком малым.

Due to antenna characteristics, a multi-antenna array requires that the distance between antennas be maintained at more than half a wavelength. If the distance is close, they will interfere with each other and affect the sending and receiving of signals.

8

диаграммообразующая

Everyone has seen a light bulb glow, right?

На самом деле, когда базовая станция передает сигнал, это немного похоже на свечение лампочки.

Сигнал излучается в окружающую среду. Свет, конечно, освещает всю комнату. Если же нужно осветить только определённую область или объект, то большая часть света будет потрачена впустую...

То же самое относится и к базовым станциям, где тратится много энергии и ресурсов впустую.

Can we find an invisible hand to bind the scattered light?

This not only saves energy, but also ensures that the area to be illuminated has enough light.

Ответ: да.

Это — формирование луча.

На базовой станции установлена ​​антенная решетка, и путем управления фазой радиочастотного сигнала лепесток электромагнитной волны после взаимодействия становится очень узким и направленным на мобильный телефон, которому предоставляются услуги, и может изменять направление в зависимости от движения мобильного телефона.

This spatial multiplexing technology changes from omnidirectional signal coverage to precise directional service without interference between beams.Provide more communication links in the same space, greatly improving the service capacity of the base station.

Straight ones can be broken into curved ones. . . Is there anything else that communication experts can’t do?

9

Don't charge me any money, okay?

In the current mobile communication network, even if two people call each other's mobile phones face to face (or send photos to each other through mobile phones), the signals are relayed through the base station, including control signaling and data packets. . .

В эпоху 5G это не всегда так.

Пятой важной особенностью 5G является D2D, то есть связь между устройствами.

10

DXNUMXD

В эпоху 5G, если два пользователя, находящиеся под управлением одной базовой станции, обмениваются данными, их данные больше не будут передаваться через базовую станцию, а напрямую с одного мобильного телефона на другой.

In this way, a large amount of air resources are saved and the pressure on the base station is reduced.

However, if you think you don’t have to pay, then you are doing Tucson a disservice.

Управляющие сообщения по-прежнему должны передаваться с базовой станции. Вы используете ресурсы спектра. Как оператор может вам это позволить?

постскриптум

I believe that through this article, everyone has a deep understanding of 5G and the communication knowledge behind it. And all of this is just based on mathematical formulas that a primary school student can understand. Isn't it?

Технологии связи не являются чем-то загадочным. Будучи самым ярким сокровищем в короне коммуникационных технологий, 5G — это не недостижимая инновационная революционная технология. Это скорее эволюция существующих коммуникационных технологий.

As an expert said -

The limits of communication technology are not limitations in technical technology, but inferences based on rigorous mathematics. It is basically impossible to break through in the foreseeable future.

How to further explore the potential of communications within the scope of scientific principles is the tireless pursuit of many strivers in the communications industry.

Итак, на сегодня всё.

Данная статья воспроизведена из "IoT IQ«Поддерживая защиту прав интеллектуальной собственности, пожалуйста, указывайте первоисточник и автора при перепечатке. В случае нарушения авторских прав, пожалуйста, свяжитесь с нами для удаления публикации».