Research And Design Of Miniaturization Base Station Array Antenna In Sub-6GHz

With the continuous development of mobile communication,more and more indoor application scenarios have been proposed,such as smart office,smart home and so on.Indoor communication quality is easily affected by building structure,traffic and other factors.Adding micro base station is an effective method to ensure good communication quality.Due to the coexistence of multiple wireless communication technologies,it is required that the micro base station antenna can work in multiple unconnected frequency bands,and should have smaller volume and better radiation performance.Based on this,this thesis based on the monopole antenna researches and designs the micro base station array antenna applied to Sub-6GHz which could work on multi frequency,have high isolation,compact structure and excellent radiation performance.The main contents are as follows:(1)A miniaturized dual band MIMO antenna covering WLAN band is designed,which overall size is 25×50×0.8mm3.The antenna consists of two symmetrical dual frequency antenna units and a parasitic branch.The antenna is fed by microstrip line.By loading inverted L-shaped branches on the ground,the working frequency band of the antenna is extended to achieve dual band,and the isolation of high frequency band is effectively improved.The dual frequency decoupling problem is transformed into single frequency decoupling.The method of loading parasitic branches is used to improve the isolation of MIMO antenna in low frequency band.The final simulation results show that the working frequency band of the antenna is 2.352.5 GHz and 4.77-6.14 GHz,and the isolation is less than-20dB in the whole working frequency band.(2)A miniaturized tri-band MIMO antenna is designed,which completely covers the 5G N78 frequency band and WLAN frequency band.In order to obtain a more compact structure,coplanar waveguide feeding is adopted.The overall size of the antenna is 28×50×1.6mm3.The antenna excites the low frequency resonance point by the T-shaped monopole,and obtains the medium frequency resonance point by slotting on the floor.Finally,in order to prolong the current path,the vertical part of the monopole is slotted and loaded with L-shaped branches to obtain the high frequency resonance point.The polarization diversity is achieved by placing the two antenna units orthogonal.Meanwhile the isolation of antenna is improved.The final simulation results show that the-10dB working frequency band of the antenna is 2.2962.554GHz,3.364-3.664GHz and 5.572-6.886GHz,and the isolation is less than-20dB in the whole working frequency band.These two antennas have the advantages of low profile,simple and compact structure and high isolation compared with similar antennas,which provides a new idea for the design of micro base station antenna.