Design On Switchable Frequency Selective Surface Based On PIN And Inductance

The switchable frequency selective surface(FSS)is equivalent to the movement of the frequency selective surface in a certain frequency band,and it can change the position of the frequency band actively to adapt to changes in the external environment.Therefore,this paper focuses on the implementation of multi-pass band switchable frequency selective surface and the optimization of electromagnetic properties based on the equivalent circuit method.The design and processing test of the designed FSS are carried out subsequently.The main work and innovation points of this paper are as follows:(1)Firstly,four types of designed switchable frequency selective surface are summarized and optimized.Then,the electromagnetic characteristics and working principle of FSS are researched based on the equivalent circuit method,and the advantages and disadvantages of the four types of switchable frequency selective surfaces are compared and analyzed.(2)Secondly,combining the advantages of PIN and Inductor on the switchable frequency selective surface,a hexagonal slot switchable FSS based on PIN and Inductor is proposed on the basis of the square slot FSS and the influence of multi-screen on the frequency selective surface.Considering the influence of the impedance of the PIN and the Inductor on the frequency selective surface and the influence of the active device itself as the feeder,the PIN and the Inductor are alternately loaded between the FSS units.Contoling the switch of the upper and lower PIN can achieve several pass-band,and the transmittance at the resonance frequency point is greater than 90%.Smart and switchable multi-passbands improves the flexibility of the frequency selective surface significantly and expands the scope of application in antenna stealth.(3)Finally,optimizing the a hexagonal slot switchable FSS based on PIN and Inductor.The PIN and the Inductor are connected between the FSS units to affect the transmission characteristics of the designed FSS.Controling the on and off states of the upper and lower PIN can also achieve three passbands in a certain frequency band,and the designed FSS has better electromagnetic wave transmission rate and go downhill fast off-band,and improve the precision on antenna stealth application.