摘要
The 5G mobile communication systems are being deployed worldwide and China has been a global leader in the new technology.The number of base stations for 5G mobile communications is increasing by more than ten thousand every week in China.By the end of this year,about 500000 base stations will be built up nationwide,covering more than 300 cities.The beyond 5G(B5G)mobile systems with enhanced transmission technologies are also being developed and attracting much attention.The emerging millimeter wave(mmW)and massive multiple-input multiple-output(MIMO)technologies are expected to become key enabling technologies for 5G/B5G mobile communications.In China,the mmW bands 24.75–27.5 GHz and 37–42.5 GHz have been allocated for future 5G/B5G trials and it is anticipated that the 5G/B5G mobile communication systems based on mmW massive MIMO technologies will be ready for commercial use in 2022.As the key components in these communication systems,antennas and RF front ends play an important role in implementing ubiquitous connection among hundreds of different devices in 5G/B5G networks.