Investigation On Electromagnetic Cancellation And Spiral Wideband Frequency Selective Surface

With the rapid development of science and technology,the modernization of national defense has also developed rapidly,stealth performance has become an indispensable element of advanced aircraft and other military equipment.Frequency selective surface(FSS)can effectively reduce the radar cross section(RCS)of antenna and aircraft;the principle of space electromagnetic wave interference cancellation and electromagnetic cancellation technology can effectively counter electromagnetic interference and reduce the radar echo of weapon platform.Based on the above motivation,the paper focuses on the following aspects.First of all,based on the basic theory of FSS and the practical application of FSS radome,the working mechanism of Archimedes spiral FSS and plane equiangular spiral FSS were studied.On this basis,combined with the engineering application,two kinds of multi-layer spiral FSS were studied and designed,and the influence of structural parameters on their performance was analyzed.The simulation results show that they have the characteristics of wide passband and low insertion loss,and triple-layer Archimedes spiral composite FSS and triple-layer combined FSS broaden the stopband bandwidth of double-layer FSS.The double-layer Archimedes spiral composite FSS and double-layer combined FSS were fabricated and experimentally studied,and the results show that the double-layer spiral FSS has the characteristics of wide passband and low insertion loss,which is consistent with the simulation results.Subsequently,combined with the basic principle of space electromagnetic wave interference cancellation and the mechanism of electromagnetic cancellation,several design ideas of electromagnetic cancellation metasurface were proposed.On this basis,in order to improve the dynamic range of FSS structure in frequency band,the concept of reconfigurable electromagnetic cancellation metasurface was introduced.The reconfigurable structure of the microstrip circuit was changed by loading the RF switch,the function that the working frequency band can be changed dynamically was realized,and the dynamic bandwidth of electromagnetic cancellation metasurface was improved.The simulation results show that the reconfigurable electromagnetic cancellation metasurface can not only has good spatial filtering characteristics for horizontal and vertical polarized incident waves in the working frequency band,but also can switch the working frequency band flexibly according to the needs.The 11 ×11 reconfigurable electromagnetic cancellation metasurface array was fabricated.The correctness of the principle and method of frequency reconfiguration is verified by experiments,and the simulation is in good agreement with the experiment.Finally,a metasurface integrated with electromagnetic cancellation and antenna was studied and designed.Through the control switch of antenna and electromagnetic cancellation metasurface,the flexible switching of electromagnetic cancellation function and antenna function was ensured,the problem of integration of stealth structure and antenna structure was broken through,and the function of radome stealth in radio silence and wave transmission in working was realized.On this basis,a quarter to sixteen microstrip power distribution feed network was designed,and the design of 4 × 4 metasurface array integrated with electromagnetic cancellation and antenna was optimized,and the characteristics of antenna function and electromagnetic cancellation were verified.