Broadband And Miniaturization Design Of 5G Base Station Antenna

With the continuous development and improvement of communication technology,5G technology has been widely applied in modern urban communication business,serving as the backbone of communication business today.5G technology can provide higher communication rates,lower latency,more connections,higher security,and more flexible business deployment capabilities,providing great convenience for humans.As an important carrier for receiving and transmitting 5G communication signals,the performance of base station antennas directly affects communication quality.However,as one of the key technologies of 5G,massive MIMO technology requires base station antennas to occupy a large amount of space resources,posing a more severe challenge to base station antennas.The biggest challenge faced by many scholars and engineers at present is to achieve broadband and miniaturization of base station antennas while ensuring their good characteristics and meeting various indicators of communication needs.This work is mainly based on the theory of electromagnetic fields,electromagnetic waves,and equivalent circuits.Starting from the research history of 5G base station antennas,the research status of base station antennas and AMC surfaces at home and abroad is summarized and analyzed according to antenna types such as cross dipole,microstrip antenna,slot antenna,and magnetoelectric dipole.Then summarize the performance indicators of antenna applications,the design principles of cross dipole antennas,and the working principles of AMC surfaces.Finally,miniaturization research and exploration were conducted on the design of Sub-6GHz frequency band base station antennas in 5G applications.In the process of optimizing broadband miniaturization antennas for base station applications,various performance indicators of the antennas were ensured to still meet communication needs.The main research content of the paper is as follows:(1)To meet the needs of multiband applications in base stations,a dual polarization cross dipole broadband antenna with operating frequencies ranging from approximately 2.2GHz to3.8GHz is designed.This antenna starts from a relatively narrow bandwidth T-shaped dipole pair and adds new resonance points to the antenna by adding rectangular parasitic patches,thereby expanding into a dual resonance point antenna and improving its working bandwidth.In addition,by improving the rectangular parasitic element to a butterfly type parasitic element and introducing resonance points on top of the double resonance points,the working bandwidth is further improved.In addition,the distance from the bottom of the antenna is approximately0.28 λ.An open box reflector has been introduced,which improves the axial gain of the antenna while also providing stable broadband cross polarization ratio and half power beam width.(2)In order to meet the needs of multiband applications and achieve antenna miniaturization design,a dual frequency coplanar co aperture base station antenna has been designed.The low frequency unit radiation structure is a circular patch,and the feeding method is coupled with a Y-shaped mircostrip line,with a working frequency range of 0.69 GHz to0.96 GHz.The high frequency unit radiation structure is a rectangular patch with L-shaped slots,and the feeding method is mircostrip balun,with a working frequency range of 3.3GHz to3.8GHz.The dual frequency shared aperture antenna is integrated by embedding four high frequency units in one low frequency unit,placing the radiation structures of the high frequency and low-frequency units on the same plane,effectively improving the antenna space utilization rate and reducing the antenna unit printing cost.In addition,by optimizing the radiation structure of the low-frequency unit,the induced current caused by the high frequency unit on the low frequency unit is reduced,and the port isolation of the dual frequency shared aperture antenna is improved.(3)In order to obtain a lower profile height of the dual frequency co-planar shared aperture antenna,an AMC surface with a working frequency covering 0.69GHz-0.96 GHz was designed to replace the metal reflector of the low frequency unit designed in(2),thereby reducing the overall profile height of the dual frequency co-planar shared aperture antenna and further achieving miniaturization.The AMC surface is composed of 9×9 AMC units,with an overall size of approximately 330 mm × 330 mm,adjust the height of the dual frequency co-planar shared aperture antenna profile from 0.28λ to 0.15λ.After replacing the AMC surface,dual frequency co-planar shared aperture antenna can not only ensure that the electrical parameters of the high frequency and low frequency units still meet the design requirements,but also ensure that the radiation characteristics of the high frequency and low frequency units remain basically unchanged,effectively achieving miniaturization functions.