Design And Research Of Base Station Antennas For Mobile Communications

In recent twenty years,the mobile communication system has been developed rapidly.With the overall popularization of the fourth generation mobile communication system and the accelerated promotion of 5G communication system,these put forward higher design requirements for base station antennas.The miniaturization,dual polarization,wide band or multi-band antennas become the main research direction for base station antennas.In this thesis,electromagnetic dipole base station antennas are studied,and the main work includes three aspects.First of all,according to the complementary antenna theory and combined with the common electromagnetic dipole antenna model,a miniaturized broadband dual-polarization electromagnetic dipole antenna was designed.By adjusting the shape of the planar dipole antenna,the antenna could achieve the miniaturization.The impedance bandwidth of the antenna could be increased effectively by using the two linear tapered feeding strips.As shown in measured results,the antenna obtains a stable gain and good directional radiation ability in the common base station communication frequency band(1.7GHz-2.69GHz).Secondly,on the base of the above designed antenna,a compact dual-band dual-polarization electromagnetic dipole antenna was presented.By redesigning the shape of the radiating element of the antenna,adding perfect conductor patch under the horizontal radiating element and adding the corner reflector around the antenna,the antenna still has stable gain and excellent directional radiation ability in different frequency bands(0.8GHz-1.0GHz,1.7GHz-2.4GHz).According to the simulation results and measured results of the antenna,the designed dual-band dual-polarization antenna can be applied to the wireless communication systems.Finally,the base station array antenna in practical communication system is studied.On the base of the first antenna unit,an eight-cell wideband dual-polarization base station array antenna design is proposed.The effects of the antenna element spacing,the shape of the antenna reflector and the number of antenna elements on the radiation performance of the antenna array are analyzed by software simulation.And then,the power divider network is designed to feed the array antenna.According to the simulation results,the proposed array antenna meets the requirements of the actual base station array antenna and can be applied to the wireless communication systems.