Study On Fabry-Perot Antenna And Array

With the emergence of diverse application scenarios,as an important part of communication technology,antennas has been brought to diversity.Broadband and high gain has become an inevitable trend of antennas.In comparison with the traditional high gain antenna,Fabry-Perot resonant cavity antenna have the advantages of high gain and simple structure.It has become a research hotspot in recent years,but its gain bandwidth and impedance bandwidth are slightly narrow.This kind of antenna generally consists of feeding antenna and reflecting surface which is based on electromagnetic new materialand dielectric substrate in order to improve the antenna gain.In the setting of what has mentioned above,a Fabry-Perot resonant cavity antenna based on dielectric substrate is designed in this paper.By punching air holes on the dielectric substrate,a gradual dielectric constant distribution and higher gain will be achieved.In addition,the relevant experiments were carried out to verify the feasibility of the design.The paper is focused on the theory of Fabry-Perot resonant cavity antenna,whose main content are as follows:?1?By means of SIW phase shifter,the influence of air holes on dielectric constant has been researched,the phase difference caused by the radius,number,distance of air holes have been summed up either.The relationship between these variables and the dielectric constant is obtained,and then it is been applied to design the antenna unit.?2?Fabry-Perot resonator antenna unit:The antenna operates from 27.5-29.5GHz,which used slot coupled patch antenna as feeding antenna.The resonator cavity is fabricated by FR4 with the thickness of 1.2mm,Rogers 3210 with the thickness of 1.27mm and Rogers RO4003C with the thickness of 1.016mm loading above the feeding antenna is the superstrate.The electric field distribution of the antenna unit of he near field based on air-holes superstrate and non-air-holes superstrate is given.When the slot coupling patch antenna with parasitic patch is used as a feed,The relative impedance bandwidth of the antenna can be improved to 11.12%,and the antenna gain is about 11.67dB.Finally,then process it and test it.The simulation and test results are also compared.?3?Fabry-Perot resonator antenna array:A feed network o four output ports and one input ports has been designed,the arc design of the corner for the divider reduces the impedance discontinuities,which plays a significant role in the improvement of standing wave.The array antenna is a linear array consisting of 4 units.The array element is 0.95₀,it's sidelobe is less than-10dB,and the gain is about 16.03dB.?4?Two kinds of beam deflection units are designed,which are the units based on the circular dielectric superstrste and the unit based on the square superstrste.The former realizes the beam deflection through the uneven distribution holes,which resulted in the main beam of the E-plane and H-plane tilted by 6°and 2°.The latter realizes large angle deflection through the off-centered square dielectric superstrste above feeding antenna.By increasing the offset between the feeding antenna and the superstrste,a larger tilted angle will be achieved.The superstrate was offset in the+y direction in steps of-2mm to 2mm,which resulted in the main beam tilted by 8°,14°,-12°,-22°.Then the second one is used for antenna array.Likewise,a tilted angle will be achieved by the off-centered superstrste.