Design Guidelines for Fishnet Frequency Selective Surfaces

In this paper, practical guidelines for the design of connected, fishnet-like, frequency selective surfaces are proposed. An equivalent circuit analysis and accurate full-wave numerical simulations are simultaneously exploited to comprehensively evaluate an exemplificative radar absorbing structure based on a resistive frequency selective surface. The FSS unit-cell shape, consisting of a resistive patch connected to the adjacent cells in a fishnet-like structure, is carefully evaluated. In particular, the FSS impedance parameters are monitored as the patch connections are geometrically varied. Indeed, an optimized FSS behavior can be achieved by acting on this parameter, developing practical guidelines for the realization of this type of fishnet configurations. As a result, the structure can achieve significant broadband performance within the 7-12 GHz band with absorption values better than -10 dB. This study may be helpful to address some practical problems from the FSS optimized design perspective.