What will happen to the future development of RF microwave antenna PCB board?
In contrast, there are still a large number of potential unused spectrum resources in the millimeter wave band. Therefore, millimeter waves have become the research hotspot of the 5th generation of mobile communication. At the WRC2015 conference, the 5th generation of mobile communication research alternative bands: 24.25-27.5 GHz, 37-40.5GHz, 42.5-43.5 GHz, 45.5-47 GHz, 47.2-50.2 GHz, 50.4-52.6 GHz, 66-76 GHZ GHZ, 66-76 GHZ, And 81-86 GHz, of which 31.8-33.4 GHz, 40.5-42.5 GHz, and 47-47.2 GHz are allowed as an optional frequency band under specific usage conditions.
Various millimeter wave devices, chips and applications are developing in full swing. Compared to the microwave frequency band, millimeter waves have their own characteristics. First of all, the millimeter wave has a shorter working wavelength and can effectively reduce the size of the device and system.
In addition, due to the short wavelength, millimeter waves have higher resolution in radar and imaging. So far, people have carried out a lot of research on millimeter waves, and various millimeter wave systems have been widely used. With the rapid development of civil technologies such as the 5th generation of mobile communication, automobile autonomous driving, and security inspection, millimeter waves will be widely used in all aspects of people's daily life.
With the rapid development of wireless communication technology, the spectrum of the golden communication frequency band below 6 GHz has been very crowded, and it is difficult to meet the needs of future wireless high -speed communication. However, in contrast, in the millimeter -wave frequency band, the spectrum resources are abundant but still have not been fully developed.
In terms of mobile communication, the scene, network structure and air interfaces of millimeter wave mobile communication systems were explored. In the current 5th -generation mobile communication (5G) research, several millimeter -wave frequency bands have become 5G candidate frequency bands. The millimeter wave technology will play a pivotal role in the development of 5G.
In a short -range high -speed communication system, the 60 GHz band has been widely researched and applied. Europe, the United States, Canada, South Korea, Japan, Australia, and my country have opened free spectrum resources in this frequency band. The 60 GHz frequency band is at the atmosphere of atmosphere. Although it is not suitable for long -distance communication, it can be used for short -range transmission and does not cause much interference to the surroundings. In recent years, high -speed GBPS communication, Wirelesshd, Wigig, near -field communication, IEEE 802.11ad, IEEE802.15.3C and other systems and standards have been developed in the 60 GHz frequency band.
Southeast University of China proposed an ultra-high-speed near-range wireless transmission standard (Q-Linkpan) working in the 45 GHz band, which has become an international standard for IEEE 802.11aj. The attenuation of the 45 GHz frequency band is less than 1 DB/KM, so not only can achieve high -speed and short -range transmission of high -speed and short -range transmission like the 60 GHz frequency band. At present, the experimental system has achieved a transmission rate of 2 GBPS in the transmission distance of 82 m, and has developed a corresponding millimeter wave chip that supports GBPS transmission.
Satellite communication coverage is widely covered. It is an important means to ensure remote areas and maritime communication and emergency communication. At present, its working frequency bands are mainly concentrated in L, S, C, KU and KA bands. With the continuous deepening of satellite communication research, it has been trying a higher frequency band.
Because the millimeter wave band can provide wider bandwidth, it can achieve a higher communication rate. In addition, low power consumption, small volume, anti -interference, and high spatial resolution are its characteristics worthy of use. At present, the main research directions of satellite and ground communication are concentrated in two windows with less attenuation, Q frequency bands and W bands, and the 60 GHz frequency band is considered to be an important frequency band to achieve galaxy communication.
In addition, the millimeter -wave light -load wireless communication (ROF) system has also developed rapidly. The optical fiber has the advantages of low cost, large channel bandwing, small loss, and strong anti -interference ability, and has become an indispensable part of modern communication systems. As mentioned above, millimeter waves have the advantages of large transmission capacity and small volume, but there are also shortcomings such as space transmission loss.
The millimeter -wave ROF system combines the advantages of millimeter wave and fiber -fiber communication, which is an effective means to achieve a long -distance transmission of broadband millimeter -wave communication. 220 GHz, 250 GHz, etc.
RF microwave imaging
Using the advantages of millimeter wave pechability and safety, millimeter wave imaging can effectively imagine the detected objects, and has been widely studied in national security, airport security inspection, and atmospheric remote sensing. Active imaging.
The millimeter -wave passive imaging is to achieve imaging by detecting the radiation energy of the surveyed object itself and distinguish the differences in different material radiation strength. Passive imaging is a safe imaging method in mechanism, which does not cause electromagnetic interference to the environment, but it has higher requirements for the strength of the signal itself and the sensitivity of the receiver. A large number of research on millimeter -wave passive imaging technology at home and abroad has carried out a lot of research.
The millimeter -wave active imaging is mainly through the millimeter wave signal of a certain strength through the millimeter wave source *****, and the difference between the target and the environment by receiving the reflex wave of the measured object, and then the counter -imaging. The active imaging system can detect non -metallic objects including plastics. It has a small environmental impact and a large amount of information obtained. It can effectively perform three -dimensional imaging.
Commonly used active imaging systems mainly include coke plane imaging and synthetic aperture imaging. The millimeter wave imaging system has been applied to many airports at home and abroad. Sun Xiaowei's team in the domestic Shanghai Micro System Institute has successfully developed the millimeter wave imaging security system, and Fan Yong team of Fan Yong of the University of Electronic Science and Technology has successfully developed the millimeter fluctuation imaging system.
RF microwave radar
The millimeter wave radar has the characteristics of frequency bandwidth, short wavelength, narrow beam, small volume, low power consumption and strong penetration. Compared with laser infrared detection, its characteristics of strong penetration can ensure that the radar can work in mog rain and snow, and the dust environment, which is less affected by the weather. Compared with the radar of the microwave band, the characteristics of the millimeter wave length can effectively reduce the volume and weight of the system and improve the resolution. These features make millimeter wave radar an important application in the aspects of car collision, helicopter obstacle, cloud detection, and missile guidance.
Micro -wave millilitarian car collision radar is mainly concentrated on the 24 GHz and 77 GHz bands. It is one of the core technologies of intelligent driving or autonomous driving in the future. In the research of helicopter millimeter wave anti -collision radar, people pay special attention to the detection effect of the millimeter wave radar on power lines.
The millimeter waves are also very important in terms of atmospheric remote sensing, including the millimeter wave cloud radar. The millimeter wave cloud radar is mainly detected for precipitation clouds, which is used to detect macro and micro parameters inside clouds, and reflects atmospheric heat and power processes.