volume | PIER Journals

2005-08-23

Aspects on the Phase Delay and Phase Velocity in the Electromagnetic Near-Field

Johan Sten,

Dr. Johan Sten

VTT Information Technology

Finland

Homepage

A. Hujanen

Dr. A. Hujanen

VTT Information Technology

Finland

Homepage

, Vol. 56, 67-80, 2006

doi:10.2528/PIER05051201 | Google Scholar

Abstract

The phase of a complex field and its speed of propagation are fundamental concepts of electromagnetic wave motion. Although it seems to be well-known that faster than light propagation of the phase may occur in, e.g., waveguides and certain dispersive media, it is often ignored that a similar phenomenon, in fact a very marked one,presents itself in the near-field of an arbitrary oscillating current in vacuum. Connected herewith is the observation that the phases of the transverse field components of a dipole approach kr - π/2, and not kr, in the radiation zone. This article illustrates these phenomena by theoretical and numerical examples as well as indicates their consequences for broad-band wireless communication over short distances.

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Johan Sten, and A. Hujanen, "Aspects on the Phase Delay and Phase Velocity in the Electromagnetic Near-Field," , Vol. 56, 67-80, 2006.
doi:10.2528/PIER05051201

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