Common-Aperture Antenna Of Sub-6GHz And Millimeter-Wave For 5G Smartphone

In recent years,with the rapid development of the fifth generation（5G）mobile communication technology,it is the future trend that the antenna in 5G smartphone covers both sub-6GHz band and millimeter wave band.However,the internal space of smartphone is very compact,so it is very meaningful and challenging to realize the common aperture / coexistence design of sub-6GHz antenna and millimeter wave antenna in 5G smartphone.Under the background,this thesis proposes three antenna designs that can be applied to 5G smartphone.The main work is summarized as follows:Firstly,the research background of the thesis is introduced.By analyzing the main research direction and research status of 5G smartphone antenna at home and abroad,the research significance of this thesis is highlighted.Then,the basic theories of smartphone sub-6GHz antenna and millimeter wave antenna are summarized.It includes the basic parameter index of the terminal antenna,the common antenna types of the terminal and the design idea of the common aperture antenna of the terminal,which provides a theoretical basis and guidance for the antenna design of 5G smartphone.Secondly,a common aperture antenna of sub-6GHz and millimeter wave bands is designed,which is applied to 5G smartphone with metal frame.The sub-6GHz antenna is composed of a dual-loop structure formed between the metal frame and the ground plane of the PCB main board.The millimeter wave antenna is composed of a connected slot antenna array etched on the top metal frame and a monopole antenna array arranged on the top clearance region.Thanks to the end-fire characteristics of the connected slot antenna array and the broad-fire characteristics of the monopole antenna array,the proposed millimeter wave antenna array has good radiation uniformity in threedimensional space.In addition,the band stop matching circuit is introduced into the sub-6GHz antenna and the high pass filter is introduced into the millimeter wave antenna to solve the interference problem of the millimeter wave antenna to the sub-6GHz antenna in the common aperture design.Thirdly,a coexistence design scheme of sub-6GHz 6×6 MIMO antennas and millimeter wave antenna is proposed,which is applied to 5G smartphone with seamless metal frame.Because the slot on the metal frame will affect the beauty and firmness of the smartphone,instead of opening a slot on the metal frame as in the first antenna scheme,two inclined parasitic radiators are introduced above and below the metal frame to solve the blocking problem of the metal frame on the millimeter wave antenna.In this way,the beam can also achieve good uniform coverage in three-dimensional space.Finally,a dual polarization millimeter wave antenna with 3D beam coverage characteristics is designed,which is applied to 5G smartphone.Although the millimeter wave antennas in the first two schemes can achieve uniform beam coverage in threedimensional space,they are single polarized.The dual polarization antenna can expand the channel capacity and establish a better connection with the base station.Therefore,by using the staggered arrangement of 8 folded monopoles and 8 folded dipoles,the vertical and horizontal polarization antennas can have good radiation uniformity in threedimensional space through ingenious design.In this thesis,three 5G smartphone antennas are simulated and analyzed,and the first and third antennas are fabricated and measured.The results show that the simulation and measurement results are basically consistent.