Research And Design Of ESPAR Antenna Based On Dielectric Resonator

The beam control capability of phased array antennas is traditionally provided by phase shifters.However,the phase shifter occupies a considerable cost of phased array system and the phase shifter has a considerable loss in X-band and above.Electronically Steerable Parasitic Array Radiator(ESAPR)antenna using varactor diode or pin diode instead of phase shifter can reduce power consumption and cost of the system,which has great prospects for commercial applications.This study includes three aspects:Firstly,the influence of different slot shapes on antenna performance is studied.A 3 GHz“hourglass”slot-coupled microstrip ESPAR antenna is proposed.Different beam steering can be achieved by changing the reactance loaded on the parasitic patch.HFSS simulation results show that the array can achieve-37°?37° continuous beam steering while maintaining impedance matching,and the maximum radiation gain can reach 9.14 dBi.Secondly,an Electronically Steerable Parasitic Array Radiator(ESPAR)is proposed which excites TE113 higher-order mode.The array consists of a feed-perforated dielectric resonator(PDR)and two parasitic perforated dielectric resonators.The perforation technique is used to reduce the relative dielectric constant of the dielectric resonator to increase the antenna bandwidth,and the reactance value applied to the parasitic dielectric resonator is changed to realize the steering of the main lobe pattern.The relative bandwidth of the ESPAR array antenna-10dBi is about 18.3%(10.09GHz?12.11GHz),and the beam steering can be achieved from-32° to 32° at 11GHz,and the impedance matching is maintained during beam steering.Thirdly,a three-cell slot-coupled dual-frequency dielectric resonator(DRA)Electronically Steerable Parasitic Array Radiator(ESPAR)with TE111 mode and TE113 mode hybrid is designed for the first time.The simulation is performed on the software CST by combining the dielectric waveguide model(DWM)and matlab to calculate the resonant frequencies of the tE111 mode and the TE113 mode.The low-frequency TE111 mode operates at 3.61 GHz,and the high-frequency TE113 mode operates at 6.15 GHz.When the impedance matching is maintained,the antenna scan angle is-22°?220°at 3.61 GHz,and the-3dB half-power beamwidth is 49.20°?59.9°,and the scanning angle is-20°?20° at 6.15GHz,and the 3-dB half-power beamwidth is 39.8??50.5°.The antenna has good directivity.