Research And Design Of Miniaturized Dual-Polarization Broadband Base Station Electrical Downtilt Antenna

Antenna is a basic device of mobile communication systems.With the performance improvement of mobile communication terminals,it is necessary for base station antenna to hold higher reliability.Considering that the current mobile communication market is still coexisting with 3G and 4G communication modes,and the antenna volume in the base station construction is very large,a miniaturized,broadband dual-polarization base station antenna is coming out.In addition,in order to make the miniaturized base station antenna array adjust the coverage,it is particularly required that the base station antenna array has the function of electrical downtilt.In order to obtain a novel miniaturized base station antenna array,the following research works are carried out:First of all,this paper describes the research advances of the array elements and the base antenna arrays in recent years.After summarizing the characteristics of the base station antennas mentioned in these literatures,the miniaturized antenna array is realized by reducing the number of elements.At the same time,in order to make the miniaturized base station antenna array have the function of electrical downtilt,it is especially necessary to design a phase shifter to deploy in the proposed base station antenna.Referring to the design literatures of phase shifter,a mechanical dielectric phase shifter is designed.Then,in order to obtain the appropriate gain of base station antenna,a six-element antenna array is presented in this paper,and at the same time,three different shapes of sidewalls are proposed on the reflector plate of the six-element antenna array to improve the radiation performance of the antenna array.To verify the effect of the sidewalls on the radiation performance of the antenna array,the radiation performance parameters of the antenna array under four different reflectors(three arrays with sidewalls and one array without sidewalls)are compared.Simulated results show that the ladder sidewall has a strong effect on improving the radiation performance of the antenna array.In addition,in view of the product cost of the phase shifter and the influence on the performance of the base station antenna array,a one-five-structure longitudinal sliding phase shifter is proposed in this paper.The design principle of the phase shifter is simple with obvious practical effect,which is very suitable for the miniaturized base station antenna array proposed in this paper.Finally,the proposed antenna array and phase shifter are physically processed and combined to obtain the miniaturized,broadband,dual-polarized base station antenna array.Its operating frequency band is from 1.71 GHz to 2.69 GHz,which basically covers the operating frequency band of mobile communication systems.The proposed antenna array has a wide downtilt angle range(0 ° ~ 10 °),which can fully reduce interference between adjacent areas.In addition,the circuit parameters,radiation parameters and the third-order passive intermodulation performance for the miniaturized base station antenna array are also measured.The measured results show that the miniaturized base station antenna array has a variety of excellent radiation performance,so that the proposed base station antenna array can become a powerful competitive product in the current communication market.