Title :
FDTD characterization of evanescent modes-multimode analysis of waveguide discontinuities
Author :
Navarro, Enrique A. ; Bordallo, Thamar M. ; Navasquillo-Miralles, Joaquín
Author_Institution :
Dept. of Appl. Phys., Valencia Univ., Spain
fDate :
4/1/2000 12:00:00 AM
Abstract :
In this paper, a finite-difference time-domain numerical dispersion relation for evanescent waves is derived, and its impact on the modeling accuracy is studied. The numerical evanescent constant is found to differ from the analytical one. As a result, a correction must be used to compute discontinuity parameters. This influences the reference plane chosen for the analysis of propagating modes. Moreover, on calculating multimode transmission and reflection coefficients, the dispersion for evanescent higher order modes is determinant. The dispersive relation is derived, discussed, and used to correct the evanescent constants for the multimode analysis of a waveguide discontinuity
Keywords :
S-matrix theory; dispersion (wave); finite difference time-domain analysis; waveguide discontinuities; FDTD characterization; discontinuity parameters; evanescent modes; modeling accuracy; multimode analysis; numerical dispersion relation; propagating modes; reference plane; reflection coefficients; transmission coefficients; waveguide discontinuities; Boundary conditions; Central Processing Unit; Dispersion; Finite difference methods; Microwave devices; Microwave theory and techniques; Planar waveguides; Time domain analysis; Warranties; Waveguide discontinuities;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
