The Design Of Dual Frequency Reconfigurable Antenna With Common Aperture

Reconfigurable antenna as a new kind of antenna,it has been receiving more and more attention.It can dynamically adjust the operating frequency,radiation patterns,polarization characteristics of the antenna by controlling the states of diodes according to the working environment of the antenna.Compared to traditional antenna,it has many advantages of small size,light weight,strong ability of anti-interference,wonderful confidentiality,and broad prospects for development.In addition,the microstrip patch antenna has many merits,such as a low profile,light weight,easy to be shaped and realize circular polarization.The dissertation is mainly concentrated on the design of reconfigurable microstrip antennas.The author's major contributions are as follows:In this paper,consideration and simulation of U-slot microstrip patch antenna is systematically researched,meanwhile,simulation and analysis are carried out in detail by using simulation software HFSS.Based on above efforts,a novel design of frequency reconfigurable with polarization diversity based on PIN diodes is proposed.The working frequency is 1.67 GHz and 2.35 GHz for different states of diodes,respectively.Moreover,the antenna can radiate with left-hand circular polarization(LHCP)at the lower band,and linear polarization(LP)can be generated at the higher band.Finally,the processing and test of reconfigurable antenna is discussed and studied,and it is deserved to be mentioned that the location of diodes can make a big difference to the performance of the antenna,which lays the foundation for the later research.To control the status of the diodes,the design of bias circuit will be introduced in this paper.According to the design,research and simulation is performed in the HFSS,the influence of the loading position on the antenna performance is simulated and analyzed at the same time,aiming at minimizing the influences caused by the bias circuit.