Analysis and design of a single layer double square slot frequency
selective surface with single stopband between double passbands
Square loop and square slot are the simplest and commonly used elements
of frequency selective surfaces (FSSs) providing bandstop and bandpass
responses, respectively. Despite it is already known that employment of
a double square slot structure presents a tunable stopband between two
passbands, it is not clear which parameters of the structure are crucial
for tunning the inbetween stopband. We propose an analysis of a double
square slot FSS considering its element as a parallel connection of
square slot and square loop predicting two geometrical parameters of the
constituent square loop are crucial for tunning the inbetween stopband.
The stopband is tunable by changing geometrical parameters of the
constituent square loop and does not depend on geometries of the
constituent square slot. The validity of this analytical prediction is
verified by full wave EM simulation results.