Research And Design Of Reconfigurable Antennas Based On Metasurface And PIN Diodes

Communication system is developing rapidly,in order to meet the needs of information interaction,antenna as an important part needs to be more complex and multi-functional,so that the antenna volume and weight become larger,cost increase,mutual interference aggravation and other problems,for this problem,a simple and low-cost solution is proposed-the use of reconfigurable antenna by adjusting the state variable device to change the antenna structure or size to achieve antenna performance change.As a new type of antenna type of communication system,reconfigurable microstrip antenna can reconstruct the working frequency and beam direction by changing the antenna structure,providing good multi-functional characteristics of a single antenna and avoiding the electromagnetic compatibility problems caused by many system antennas.In this paper,two patterns of reconfigurable patterns and one frequency reconfigurable antenna are finally designed and tested by introducing the active device PIN diode and metasurface,and using AnsoftHFSS19.0 for modeling and simulation testing.The main research content of the paper is divided into the following three parts:1.In order to cope with the problem of poor security in C-band point-to-point communication,this paper proposes a pattern reconfigurable antenna with dual lobes.The antenna is reconstructable in its pattern in four modes by loading PIN diodes in the gaps between the periodically arranged metasurface elements.The antenna can operate in the frequency bands of 5.08-5.28GHz and 5.65-6.03GHz,and its E-plane pattern can be switched between 0°,0° and 180°,45° and-135°,-45° and 135°.2.In order to cope with the problems of power waste and signal noise interference in the process of reflecting and receiving signals from the antenna,the directional characteristics required to complete the specified task.Based on the first paragraph,the shape of the metasurface unit and the cylindrical air cavity between the substrates are improved,the antenna can still work in four different states,the working frequency band is 5.27-5.82GHz,and its E-surface pattern can be switched between 0°,180°,±30°,and the reflection coefficient performance is greatly improved.3.In order to cope with the problems of single frequency reconfigurable mode,large size,and few working frequency bands in multi-band bands,this paper proposes a multi-mode frequency reconfigurable microstrip patch antenna applied to the S and C bands.We introduce a coplanar waveguide feeder patch antenna printed on one side of the FR4 substrate,and the other side is completely etched copper as a metasurface array.The square patch is tilted 45° relative to the horizontal plane to obtain a diamond shape,thereby changing the effective width of the antenna radiation,and the microstrip line is used to feed.A C-slot is opened in an inclined rectangular patch,a rectangular slot is opened in the feeder and a PIN diode is placed in both slots,and an L-shaped resonant branch is loaded with two ground connections to connect it to the PIN diode.The tuning of the S-band and the five operating frequency bands in the C-band is achieved by controlling the PIN diode opening and closing.