5G mobile phones will be widely launched this year. The Ministry of Industry and Information Technology has already indicated that in the second half of the year, 5G trials will be launched in some regions, and 5G mobile phones will be released gradually after this time. 5G network will bring a lot of new experiences. For our mass users, 5G is the most attractive element of ours. It is also a network speed that is several times higher than 4G. 5G can have several times or even dozens of times 4G LTE network speed, can not be separated from the various new technologies and new standards used behind, the use of millimeter wave technology is undoubtedly the most critical part.

What is the millimeter wave?

What is the millimeter wave? In fact, we can see through the high school physics textbook, which is essentially a high-frequency electromagnetic wave, which is an electromagnetic wave with a wavelength of 1-10 mm, which is usually an electromagnetic wave with a frequency between 30 GHz and 300 GHz. It is one of the main frequency bands used in 5G communication.

In 5G communication, two communication bands are mainly used, and Sub-6GHz is a low frequency band, which mainly uses the frequency band below 6 GHz for communication. The millimeter wave band uses a high frequency millimeter wave of 24 GHz to 100 GHz for communication. At present, the utilization of millimeter waves by 5G is mostly concentrated in several frequency bands of 24 GHz/28 GHz/39 GHz/60 GHz.

The fundamental of network communication speed is actually the amount of data that can be received in a unit of time. The communication base station and the mobile phone are like the transmission of goods between two logistics sites. The goods are the data that needs to be transmitted. The electromagnetic wave used by our communication is connected between the two sites. It is like a highway; The data transmission between the two is like the goods in a truck.

If we want to transport all the goods to the other end, we can increase the capacity of the truck so that it can transport more cargo at a time, so that when the truck speed is fixed (the electromagnetic wave transmission speed is fixed to the speed of light), The goods are shipped in a short period of time. Simply speaking, it is to increase the amount of data that can be carried in communication electromagnetic waves to improve communication efficiency and speed up the network.

For example, the current 256-QAM is based on the principle of increasing the network speed, but this approach has certain limitations. It is not able to increase efficiency without limit. This method will increase the power consumption of the RF signal, and on the other hand, it will be more susceptible to noise interference, resulting in errors in decoding. The concept of switching to a truck is easier to understand. A truck is limited in size and you can't make it a train anyway.

Another way is to increase the lane and increase the number of trucks that can be peered, which is to increase bandwidth to achieve faster network speeds. This is not difficult to understand. The more lanes there are, the more trucks there are in a single unit of time, that is, the more data that can be received per unit of time, the faster the response is at the speed of the network.

The simplest and most rude way to increase network speed is to increase bandwidth. According to the principle of communication, the frequency of the communication signal is proportional to its maximum bandwidth, which is about 5% of the frequency. Taking the 28 GHz millimeter wave as an example, the theoretical maximum bandwidth is 1.4 GHz, which is compared with the current 4G LTE. Compared with the bandwidth of 800Mhz-2600MHz signal around 100Mhz, congenital has more than ten times the bandwidth gap.

Millimeter wave single carrier can reach 100MHz bandwidth

Carrier aggregation technology can also increase bandwidth by integrating multiple carriers to achieve higher system bandwidth. However, the use of carrier aggregation is also limited by spectrum resources. In the current 4G LTE spectrum resources, spectrum resources are scarce, and China Mobile, which has the most abundant spectrum resources in China, has only 130 MHz spectrum resources. In comparison, the millimeter-wave spectrum resources are very rich, and the frequency bands that can be allocated to operators are extremely wide, and even many continuous high-quality frequency bands can be allocated.

High bandwidth, good resources, and fast speed are the advantages of millimeter waves, and why the 5G uses millimeter waves as a carrier. At present, the millimeter wave technology has been relatively mature, and Qualcomm has once demonstrated this for us. It uses 800 MHz channels to form a high bandwidth of 800 MHz, and the network speed is close to 5 Gbps, compared to Sub-6 GHz. There is also a multiplier increase in the highest rate.

Millimeter wave is also difficult to use

The millimeter wave is actually not a new technology. It appeared a long time ago, but it has not been widely used. Because it is greatly restricted by environmental factors in communication. Because of its short wavelength, the diffraction ability is not strong, and the penetration force for buildings is almost equal to none. A slight obstacle will cause signal propagation to be blocked. Water molecules in the air are also able to absorb millimeter waves, causing their energy to decay and the range of propagation is extremely limited. Even the human body itself can cause fatal interference to the millimeter wave, and the human hand can completely block the millimeter wave signal.

For the technical solutions of millimeter wave applications, the communication industry now has a mature solution. The transmission of 4G signals is a regional coverage, similar to water ripples, without very precise directionality. The transmission of millimeter wave signals can be regarded as point-to-point dynamic transmission. It can accurately identify the position and distance between the base station and the mobile phone, and combine the millimeter wave signals to form a high-energy beam and then use beam tracking. The technology directly performs directional transmission. This type of transmission has concentrated energy and has good anti-interference, which perfectly compensates for the insufficiency of millimeter wave congenitality, enabling it to support commercial environments.

Receiving and transmitting millimeter waves in a mobile terminal is also a problem that needs to be solved. The wavelength of the millimeter wave is short, and the required antenna length is also short, which can reduce the space occupied by the antenna inside the mobile phone, which is the advantage of the millimeter wave. However, the use of millimeter waves in mobile phone terminals is also facing design challenges in all aspects of RF transmission, antenna, amplification, and reception.

Fortunately, there are also complete solutions for the use of millimeter waves in mobile terminals. Among them, Qualcomm's solution is the most representative. The new generation of millimeter-wave antenna module QTM525 integrates a series of functions such as antenna, signal transceiving and amplification in millimeter wave transmission, and these functions are combined in one tenth. Among the "pocket" modules. As long as the mobile terminal uses the module, it can directly solve the problem of millimeter wave communication. QTM 525 millimeter wave antenna module can deploy four in one mobile phone, covering all four sides of the mobile phone in all directions, allowing users to ensure the smoothness of a group of antennas, whether it is horizontal or one-handed, ensuring millimeter wave communication. reliable.

The QTM 525 millimeter wave antenna module has excellent volume control. The mobile phone equipped with this module can control the thickness of the mobile phone to 8mm. This thickness is equivalent to the current 4G mobile phone. It can extend the slim design of the mobile phone, and it can make the 5G mobile phone. It has a slim and slim design like the 4G mobile version.

The slimness of 5G mobile phones is not a problem

QTM, 525 is actually Qualcomm's second-generation 5G millimeter wave antenna module. As early as July last year, Qualcomm released the first generation of millimeter wave module QTM052, which cooperated with the Snapdragon X50 modem to provide millimeter wave support for the world's first 5G mobile phones. In view of the fact that most of the 5G mobile phones listed this year will adopt the combination of the Snapdragon 855 mobile platform + Snapdragon X50, for the 5G mobile phone terminals that support the millimeter wave introduced by several manufacturers, the millimeter wave is no longer a problem, only to be After the operator's network is built, users can experience the rapid experience brought by millimeter waves.

Millimeter wave is an indispensable part of 5G

At the beginning we have made it clear that the millimeter wave is part of 5G communication and is one of the two main frequency bands in 5G communication. It brings not only extremely fast network speed to 5G, but also the importance of 5G differentiation experience. component.

The 5G network is a complex network environment. The millimeter wave is the core experience around the center of the most closed loop. It presents the ultimate speed, but the coverage of the network signal is limited. The Sub-6GHz band takes into account the speed and The signal coverage has a balanced performance; in addition, the Gigabit LTE network is also indispensable in the 5G environment. It has the best signal coverage and can guarantee users not in places where 5G signals are not covered. A bad experience with a cliff.

Both millimeter wave and Sub-6GHz are indispensable parts of 5G. The millimeter wave is the most technically difficult, and may not be taken seriously in the early 5G, but the 5G lacking the millimeter wave is the 5G without the soul.