Surface impedance absorbing boundary condition used for the simulation of frequency selective surfaces

Frequency Selective Surface (FSS), which is a kind of emerging artificial metamaterial, is widely used in research and engineering areas and attracting more and more attention. In this paper, we apply the finite difference time domain method including the surface impedance absorbing boundary condition (SIABC) to simulate different FSS. Both the magnetic field ( H-) and electric field (E-) collocated SIABC are implemented. The H-collocated SIABC could be directly combined with the periodic boundary condition without extra formula derivation while the updating equations for the E-collocated SIABC combined with PBC are derived. The reflection error and stability of the proposed method are analyzed, and different FSSs including a dipole FSS and a Jarusalem cross are simulated under normal incidence. The co-polarized reflection and transmission coefficients of the FSSs are obtained. Good agreement is reached with the FDTD method including convolutional perfectly matched layer, while up to 41.88% of time and 40.98% of memory is saved.