Modeling of capacitive FSS with thick metal patches by the MoM/BI-RME method

A novel technique for the modeling of capacitive frequency selective surfaces (FSS) with thick metal patches is presented in this paper. While capacitive FSS are usually analyzed under the hypothesis of infinitely thin metal patches, taking into account the finite thickness of the metal patches is important especially in the mm- and submm-wave frequency band, where patches are electrically thick and the thin-patch approximation leads to a shift of the resonance frequency. In addition, the proposed approach permits a better evaluation of conductor losses. The MoM/BI-RME method, already applied to the modeling of capacitive FSS with infinitely thin metal patches, is extended in this paper to the efficient and accurate modeling of thick-patch FSS. A validation example is reported and compared to the results obtained with a commercial software.