Collocated Sibc-FDTD Method for Coated Conductors at Oblique Incidence

Abstract

Abstract-A collocated surface impedance boundary condition (SIBC) -finite difference time domain (FDTD) method is developed for conductors coated with lossy dielectric coatings at oblique incidence. The method is based on the collocated electric and magnetic field components on the planar interface between two media, and rational approximation for tangent function of surface impedance formulation is adopted. In contrast to the traditional SIBC-FDTD implementation which is approximated with the magnetic field component on the boundary located at half-cell distance from the interface and half time step earlier in time, the collocation approach is more accurate for both magnitude and phase of reflection coefficient. By the comparison with exact results, the proposed model is numerically verified in the frequency domain for both parallel polarization plane wave and vertical polarization plane wave at varying oblique angles of incidence.

An FDTD absorbing boundary condition for anisotropic media based on NPML

“…Therefore, the research on electromagnetic characteristics of anisotropic media is of great importance in both theory and practical applications. [1] As an efficient electromagnetic simulation technique, the finite-difference timedomain method (FDTD) [2][3][4][5][6][7] is often employed for solving electromagnetic problems of this complex medium. To handle such problems using the FDTD method, one of the main challenges is the requirement of efficient and accurate absorbing boundary conditions (ABCs) to truncate the open region domains.…”

SIBC incorporated in conformal FDTD to efficiently simulate the thin conductive layer of periodic structure

“…(iii) Surface impedance boundary condition (SIBC) was incorporated in FDTD to directly analyse the thin layer. The advantage of this method is the procedure of discretising inside the thin layer with fine FDTD unit-grid can be avoided [11][12][13][14][15][16][17][18][19][20]. Since SIBC was fundamentally a frequency-domain relation, thus the challenge of this method was the implementation of a frequency-domain relation in a time-domain FDTD method.…”

“…Since SIBC was fundamentally a frequency-domain relation, thus the challenge of this method was the implementation of a frequency-domain relation in a time-domain FDTD method. In the earlier works [11][12][13][14], the recursive convolution approach was used to convert the frequency-domain equations to the time-recursive algorithm. For this purpose, the transient (time domain) impedances by inverse Fourier transform are required.…”