FDTD Dispersion Revisited: Faster-than-Light Propagation
نویسندگان
چکیده
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 paper a different interpretation is given for the governing equation. It is shown that the dispersion relation predicts fasterthan-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.
منابع مشابه
FDTD Dispersion Revisited: Faster-Than-Light Propagation - IEEE Microwave and Guided Wave Letters
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 letter 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 previous...
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