Title :
FDTD dispersion revisited: faster-than-light propagation
Author :
Schneider, John B. ; Wagner, Christopher L.
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., Washington State Univ., Pullman, WA, USA
fDate :
2/1/1999 12:00:00 AM
Abstract :
The numerical dispersion relation that governs the propagation of fields in a finite-difference time-domain (FDTD) grid was derived several years ago. In this work a different interpretation is given for the governing equation. It is shown that the dispersion relation predicts faster-than-light propagation for coarsely resolved fields. Additionally, some spectral components that were previously believed to have zero phase velocity are shown to propagate, albeit with exponential decay
Keywords :
dispersion (wave); dispersion relations; finite difference time-domain analysis; light propagation; FDTD dispersion; coarsely resolved fields; exponential decay; faster-than-light propagation; finite-difference time-domain grid; numerical dispersion relation; phase velocity; spectral components; Arithmetic; Computer science; Differential equations; Dispersion; Finite difference methods; Frequency; Stability; Time domain analysis;
Journal_Title :
Microwave and Guided Wave Letters, IEEE
