Equivalent Circuit Model of an Ultrawideband Hybrid EBG/Ferrite Structure

This letter presents the development of an equivalent circuit model for the previously presented ultrawideband and low-profile hybrid electromagnetic band-gap (EBG)/ferrite structure. It is shown that unlike the equivalent circuit models developed for traditional mushroom EBG structures, the equivalent circuit model for the hybrid structure contains a resistance representing the permeability losses due to the ferrite layer. Additionally, it is shown that both the inductor and resistor equivalent circuit components are frequency dependent and depend on the frequency dependent characteristics of the ferrite.