5G, the fifth generation mobile communication technology is a new generation of broadband mobile communication technology with the characteristics of high speed, low delay and large connection. It is the network infrastructure to realize the man-machine and object interconnection.
The Internet of things is the main beneficiary of 5G. The main driving force of 5G is not only the growing demand of consumers for faster networks, but also the proliferation of networking devices in the industrial environment. These industries increasingly rely on networking devices to collect and analyze data, make business processes more efficient, improve productivity, and continuously improve products and services. 5G is expected to help businesses more effectively manage the growing amount of information generated by the Internet of things, and improve the near instant messaging required for mission critical services such as robot assisted surgery or autonomous driving.
Circulator and isolator is one of the core devices of 5G base stations. The whole mobile communication system is generally composed of mobile communication infrastructure, mobile communication coverage system and mobile communication terminal products. Base station belongs to the basic equipment of mobile communication. Base station system is usually composed of RF front-end, base station transceiver and base station controller. The RF front-end is responsible for signal filtering and isolation, the base station transceiver is responsible for signal receiving, sending, amplifying and reducing, and the base station controller is responsible for signal analysis, processing and base station control. In wireless access network, circulator is mainly used to isolate the output signal and input signal of base station antenna. For specific applications, the circulator can achieve the following functions with other devices:
1. It can be used as antenna commoner;
2. In combination with BPF with fast attenuation, it is used in wave splitting circuit;
3. The terminal resistor is connected to the outside of the circulator as an isolator, that is, the signal is input and output from the designated port;
4. Connect the external ATT and use it as a circulator with reflected power detection function.
As one of the most important components, two pieces of Samarium Cobalt disc magnets provide the magnetic field necessary to bias the ferrite-loaded junction. Due to characteristics of excellent corrosion resistance and working stability high to 350℃ degrees, both SmCo5 and Sm2Co17 magnets are used in circulators or isolators.
With the application of 5G massive MIMO technology, the consumption of circulators and isolators has increased significantly, and the market space will reach several times of 4G. In 5G era, the requirement of network capacity is much higher than that of 4G. Massive MIMO (Multiple-Input Multiple-Output) is one of the key technologies to improve network capacity. In order to support this technology, the number of 5G antenna channels will increase significantly, and the number of single sector antenna channels will increase from 4 channels and 8 channels in 4G period to 64 channels. The doubling of the number of channels will also lead to a significant increase in the demand for corresponding circulators and isolators. At the same time, for the needs of lightweight and miniaturization, new requirements for volume and weight are put forward. In addition, due to the improvement of the working frequency band, the signal penetration is poor and the attenuation is large, and the base station density of 5G will be higher than that of 4G. Therefore, in the 5G era, the use of circulators and isolators, and then Samarium Cobalt magnets will increase significantly.
Currently main manufacturers of circulator / isolator in the world include Skyworks in USA, SDP in Canada, TDK in Japan, HTD in China, etc.
Post time: Jun-10-2021