Research On The Multilayer Spiral Array EBG Structure And It’s Application On Antenna

EBG materials are usually periodic structure and arranged by materials withdifferent dielectric constant, evolved by the photonic bandgap crystal (PBG), whichpossesses two kinds of special performance,(1) The EBG material control flexibly thetransmission performance of electromagnetic wave, with the band-stop and band-passcharacteristic;(2) the second property is in-phase reflection, that is, a bunch of theincident wave according to the surface of the EBG structure, will be reflected back withthe same phase angle to the incident wave, the phase difference of the incident wave andreflected wave is0°, while it is180°for the Perfect electric conductor, which is knownas artificial ideal magnetic conductor. This paper design a multilayer spiral array EBGstructure, which can inhibit lower band of microwave, compared with theMushroom-like EBG structure with the same size. The main work of this paper can besummarized as follows:1. The multilayer spiral array EBG structure is proposed and its reflection phase issimulated by the HFSS software. The structure possesses lower phase angle band gap,compared with the Mushroom-like EBG structure with the same size. Meanwhile, theinfluence of structure parameters on the performance of the MS-EBG structure isanalyzed. The conclusions are as follows: as the size of spiral cell, the permittivity ofsubstrate and the gap between cells increase, the resonant frequency decreases and thebandgap becomes narrow. As the increase of the height of substrate, the resonantfrequency decreases and the bandgap become wide. The width of spiral has nothing todo with the resonant frequency of MS-EBG.2. Multilayer spiral array EBG structure with patch is designed and the surfacewave bandgap of the structure is simulated. The result shows the structure possesseslower surface wave band gap, compared with the Mushroom-like EBG structure withthe same size. At the same time, we analyzed the influence of structure parameters onthe performance of the PMS-EBG structure. Results are as follows, as the size of spiralcell, the permittivity of substrate and the size of patch increase, the resonant frequencydecreases and the bandgap becomes narrow. As the increase of the width of spiral, theresonant frequency increases and the bandgap become wide. The gap between cells hasnothing to do with the resonant frequency of PMS-EBG 3. In order to improve the bandgap of Multilayer spiral array EBG structure withpatch, multilayer cone-like EBG structure and two composite PMS-EBG structure areproposed, and the properties of these structure are analyzed.4. The results of numerical simulation and testing show Mushroom-like EBGstructure and PMS-EBG structure is helpful for the forward gain of microstrip antennas,and is beneficial to axial ratio of the Archimedes antenna, and achieve Miniaturizationof the antenna.