Research On Miniaturized Efficient Frequency Selective Surface Operating In X-band

The frequency selective surface(FSS)is a kind of microwave device that has spatial filtering characteristics.Since proposed,it has been widely used in many fields.Espacially in the military field,the FSS radome can improve the stealth performance of combat units to a great extent.As the thorough research going on,the working performance requirements for FSS are also increasing in some engineering applications,some traditional FSSs can no longer meet the actrual demands.Focused on this hot research topic,a series of studies on high wave-transmissivity FSS are carried out in this paper.Firstly,started with the FSS's basic working mechanism,the filtering theory of FSS is thoroghly analysed on the field and circuit perspective respectively.Some characteristics of FSS is introduced,and furthermore,the design and implementation method of high wave-transmissivity FSS is raised.Additionally,the equivalent circuit method is introduced as the theoretical basis of the research,and both the typical single layer and multiple layers FSS's equivalent circuits are deeply investigated.Then,the working mechanism of the FSS which has the coupling surfaces is studied,and a kind of wide-band FSS is designed base on the coupling method.The result shows that the wide-band FSS has a ultra wide band over X band(the relative bandwidth reaches 98%),and it has a stable filtering property to the oblique incident wave.Moreover,a miniaturized FSS is designed by adding a fractal coupling layer in the middle layer of wide-band FSS.The MEFSS's size is only 0?/ 16,it has a high transmission efficiency in the resonance passband,and as for the miniaturazation design,it has a extremely stable filtering property to the oblique incident wave.Finally,combining the wide-band and miniaturization technique,two kinds of FSS structures are raised.One is a mutiple coupling layer structure.By means of the cascading method,it obtains a good transmission property.The other FSS refers to the C-type radar radom.Through Combinig the wide-band FSS and the radom sturcture,and then make a winding design to the midddle square ring,finally it achives a Significant miniaturized ambition.The calculation result shows that both of the two FSS structures possess high wave-transmissivity performance.The research made in this paper is noval and the content is systematic.The proposed FSS structures have excellent working performance,which have reached expected goal.The work has a important innovation significance,and may provide some guidance for future research in relative fields.