Researches On Low Profile And Miniaturized Base Station Antennas

The rapid development of economic society has accelerated our nation's informatization,the mobile communication technology has become an important industry to improve the level of economy and accelerate the speed of modernization,and runs through all aspects of people's life.Communication systems are increasingly integrated,so electronic devices are required to have smaller sizes,wider bandwidths,and more functions.This paper deeply studies the methods of antenna miniaturization and low-profile.The main work of this paper is as follows:(1)A miniaturized dual-polarization broadband base station antenna is proposed.By introducing a circular resonant patch at the periphery of a dual-polarized dipole antenna,the plane size of the proposed antenna is only 0.27 ?L× 0.27 ?L.After replacing the PEC reflector with AMC reflector which is separated from the ground,the height of the antenna is only 0.12 ?L,the antenna has a very small space volume.The relative bandwidth of the proposed antenna can reach up to 53%(VSWR<1.5),the port isolation is less than-22 dB,the cross-polarization is 28 dB,and it can achieve a good impedance matching and far-field radiation characteristics.(2)A miniaturized high isolation broadband base station antenna is proposed.By introducing two short pins on the ports of the antenna mentioned in(1),the port isolation of the antenna is lower than-33 dB.Due to the introduction of the circular resonant patch and NAMC reflector,the plane size of the antenna is only 0.27 ?L× 0.27 ?L,and the height of the antenna is only 0.12 ?L,and the antenna has a very small space volume.The bandwidth of the two ports of the antenna can reach up to 54%(VSWR<2).It covers 2G/3G/LTE communication band and has good impedance matching characteristics.The gain of the antenna is 8 dBi,the cross-polarization is greater than 30 dB,and it has good far-field radiation characteristics.(3)An extremely low-profile electromagnetic dipole base station antenna is proposed.The height of the planar electromagnetic dipole antenna proposed by Luk is improved by loading short patch.The short patch can change the antenna's surface current and improving its impedance matching characteristics the antenna's profile is just 0.04 ?L,it's the lowest electromagnetic dipole base station antenna.In addition,the relative bandwidth of the antenna can reach up to 31.2%(VSWR<1.5)and 44.5%(VSWR<2),and the gain of the antenna is 6.2 dBi.The antenna has the lowest profile,wide bandwidth,good impedance matching and far-field radiation characteristics.