Research On Antenna And Array Based On Dielectric Resonator

With the rapid development of economy and science and technology,wireless communication technology has been gradually applied to every aspect of life.The number of users and devices has been increasing year by year,which requires greater channel capacity,wider bandwidth and faster transmission rate.As a transceiver in the wireless communication system,the antenna needs to be miniaturized,broadband,multifunctional,reconfigurable,high gain and other directions.Dielectric resonator antenna stands out by virtue of its advantages such as flexible structure,low loss and high radiation efficiency,showing a broad development prospect.This article first investigates the current research status of dielectric resonator antennas at home and abroad,and then briefly describes the working principle of dielectric resonator antennas,and formulates the working modes and Q value calculations of common rectangular,hemispherical,and cylindrical dielectric resonators.Derive,and summarize the common feeding methods of dielectric resonator antennas.On this basis,the following three antennas are designed for broadband,omnidirectional,circular polarization and other characteristics:(1)Broadband omnidirectional dielectric resonator antenna.The omnidirectional antenna has the characteristics of large radiation coverage and avoiding polarization mismatching,while the broadband omnidirectional dielectric resonator antenna takes into account the advantages of miniaturization,high efficiency and wideband.The antenna uses the single-sided Alford structure to form a ring current,and then forms a stable wideband multimode resonance by extending the probe and adding the resonator disk,so as to achieve the wideband omni-directional.The final antenna operates in 2.3-3.4GHz with a peak gain of 2.1dBi and a horizontal irroundness of less than 0.4dBi.(2)Broadband circularly polarized dielectric resonator antenna.The circularly polarized antenna has small polarization loss and strong anti-multipath interference ability.Compared with the broadband electronic system,the circularly polarized antenna can effectively reduce the hardware structure and improve the system stability.The antenna forms circular polarization by cutting angles and sloting on the top,and further reduces the axial ratio by embedding metal column structure on the substrate and the bottom of the resonator,so as to realize wide-band circular polarization.Finally,the antenna works in 1.75GHz-3.0GHz,the circular polarization frequency band is 2.02GHz-2.97 GHz,and the peak gain is 6.7dBi.It is a broadband circularly polarized dielectric resonator antenna with practical significance.(3)Reconfigurable wideband circularly polarized dielectric resonator antenna array.The antenna array has strong directivity,high gain and low sidelobe.The antenna array constructed by dielectric resonator antenna has the advantages of low coupling between elements,small size and high radiation efficiency.In this chapter,a wideband circularly polarized array is constructed by using double Z slits,and liquid metal is injected into the bottom of the resonator through a slot.The reconfiguration is realized by controlling the position of liquid metal.Finally,the array works in the range of 4.74GHz-6.23 GHz,the circular polarization band is 5.15GHz-6.35 GHz,the peak gain is 12 dBi,and the inband gain is greater than 8.5dBi.