Research On High Isolation Dual-polarized And Ultra-wideband Conformal Antenna Array

In recent years,with the continuous development of communication systems and the improvement of microelectronics technology,the number of communication users is also rising rapidly.Therefore,antennas in wireless communication systems need to develop in the direction of multi-polarization,ultra-wideband and conformal arrays to increase the system communication capacity and combat multipath attenuation.In this paper,the dualpolarized antenna,ultra-wideband antenna and conformal antenna are taken as the research objects to study the dual-polarized antenna technology,ultra-wideband technology and conformal array technology.Considering the impedance bandwidth,radiation pattern,isolation,cross-polarization level and gain of antenna,the dual-polarized antenna with high isolation degree is synthetically designed.UWB conformal antenna array.The main research contents are as follows:In this thesis,the characteristics and applications of bipolar,ultra-wideband and conformal array technology are described,and the relevant electrical parameters of bipolar,ultra-wideband and conformal antenna are analyzed and deduced respectively.A broadband highly isolated dual-polarized microstrip slot antenna for 2G/3G/4G and some 5G bands mobile communications is proposed and implemented.The antenna uses two different microstrip feeding structures to improve the port isolation,namely microstrip step feeder and U-shaped feeder,and excites the vertical and horizontal polarization modes of the antenna respectively.At the same time,the isolation degree of the antenna port is further improved by opening a cross slot between the rectangular slot and two vertical rectangular slots on the floor,and the bandwidth of the antenna is expanded to realize the miniaturization of the antenna.The simulation results show that the bandwidth of port 1 is 1.69-3GHz,the bandwidth of port 2 is 1.65-2.85 GHz,the relative bandwidth of the whole antenna is 52%,the isolation degree is better than 42 dB,the gain is better than 3 dB,and the cross-polarization is better than 20 dB.It has good practical performance.A novel ultra-wideband cylindrical conformal array antenna is proposed and implemented,which can work in 3.5-12.8 GHz band and is suitable for ultra-wideband systems.The basic radiation unit of the antenna is a logarithmic periodic antenna based on arc Koch curve structure,which can communicate within 2.7-8 GHz.Compared with the traditional logarithmic periodic antenna,the proposed antenna reduces 35% of the antenna area,while the characteristics of the standing wave impedance bandwidth remain basically unchanged,which makes the antenna easier to conform with the carrier.