5G science

1. official communication origin

Application of 2. 5G wireless and wired

The main breakthrough in wireless

That is because a wired (cable, optical fiber, twisted pair) these transmission medium, in particular an optical fiber, and fully meet the needs of our usual communication rate

So bottleneck where? Short board that the signal transmission between the phone and the base station, i.e. a wireless bottleneck.

The current mainstream of mobile communication standards, 4G LTE, only theoretical rate of 150Mbps (not including carrier aggregation). This is completely wired and can not be compared.

As shown below:

3. 5G frequency of

FIG 1 is a frequency range of various wave

FIG 2 is a wavelength spectrum of each segment name, and the use of

With 1G, 2G, 3G, 4G development, the use of radio frequency is higher and higher.

This is mainly because, the higher the frequency, the more abundant frequency resources that can be used. The more abundant frequency resources, the higher the transmission rate can be achieved.

The second sentence to understand how:

First, let's explain what is information. Information, under the conditions of modern technology, we can determine the assumption that it is a digital information, it is measured in bits to be. You said a large amount of information, but also can be said that can be transmitted per second, the number of bits carried more. in the digital modulation, FSK, PSK, MSK are three basic ways, an example using 2FSK to accurately identify the presence of a carrier wherein modern technology needs to receive at least three waveform cycles, therefore, the carrier frequency is assumed 3M, then the fastest possible transmission rate of 1M bits per second. However, if the carrier frequency is increased to 3G, then the theoretical maximum transmission speed may be 1G bits per second. so, we can say that the higher the frequency, the transmission, the greater the amount of information carried. this principle, for PSK, MSK same establishment.

5G two current spectrum used, subject to the second, is currently testing the commercial frequency is 28GHZ

4. The transmission characteristics of an electromagnetic wave

C = speed of light wavelength from the formula * apparent frequency, the higher the frequency, the shorter the wavelength, the shorter the wavelength, the more close to a straight line, which is to be blocked can not be bypassed (poor diffraction), the attenuation in a transmission medium fast.

Figure:

Seen from a high frequency leads to reduction in the transmission distance, the range covered by the base station becomes small, the signal will be weak.

It means that the required number of base stations will be greatly increased, as shown:
5G so there's bound to lead to an increase, increase the cost of the cost, so there are a micro base station.

如图：传统基站与微基站的对比