Study Of Frequency Reconfigurable Liquid Antennas In S Wave Band

In the rapid development of modern communication systems,Because of different requirement,a various of antennas are produced.The Multiple functions of antennas that are lied in one platform are increasingly common.However,a plurality of antennas are bound to occupy much more space,At the same time,The tight arrangement between antennas leads to much more mutual electromagnetic interference,Eventually,They will affect the normal operation of the system seriously.The reconfigurable antennas can make one antenna meet the performance of two or even more antennas and they can effectively reduce the radar cross section of the antenna and improve the space utilization.The reconfigurable antenna alters the antenna performance by changing the effective aperture radiation of the antenna,This process redistributes purposively the surface current or the radiation of the antenna.Transforming the performances of antennas and realizing the refactories.Liquid metal has high conductivity,low-melting point,low loss and so on.These features have been widely concerned by researches.Simultaneously,PIN diodes have the advantage of quick response,cheap,small insertion loss,single wizard pass feature,These characters have been extensively used in radio-frequency circuit.These materials provide an effective solution for reconfigurable antennas.The main work of this paper is researched on frequency reconfigurable liquid antennas and polarization reconfigurable antennas in S wave band.According to the main content of the study,This article can be summarized into three parts:1.Have designed a slot coupled ring liquid metal antenna unit,The antenna adopts ring gap coupling feed structure,the upper and lower surfaces of the dielectric plate are etched with circular liquid metal grooves of different sizes and the liquid metal EGa In is injected into the grooves,The large ring realizes 3.48GHz~3.6GHz and the small loop achieves 3.6GHz~3.72 GHz.Through these two working states,The antenna can achieve frequency switching.2.A two-point T-type power divider is designed,The circular liquid metal antenna unit is adopted and a 1x2 array antenna is constituted.The performances of the antenna array can meet the requirements by properly adjusting the unit gap.3.A circular polarized reconfigurable microstrip antenna with a central frequency of 2.6GHz is designed.Two perturbation units are connected on both sides of the rectangular metal patch by two PIN diodes,The two diodes are operated in different working states by using the single wizard pass characteristic of the diodes,The antenna can convert between left and right circular polarization,The antenna has good characteristics in both working conditions and meets the design requirements.