The evolution of an electromagnetic pulse propagating through a linear, dispersive, and absorbing dielectric (as predicted by the modern asymptotic extension of the classic theory of Sommerfeld and Brillouin) is described in physical terms. The description is similar to the group-velocity description known for plane-wave pulses propagating through lossless, gainless, dispersive media but with t...

In this paper we develop a method for synthetic-aperture radar (SAR) imaging through a dispersive medium. We consider the case when the sensor and scatterers are embedded in a known homogeneous dispersive material, the scene to be imaged lies on a known surface and the radar antenna flight path is an arbitrary but known smooth curve. The scattering is modeled using a linearized (Born) scalar mo...

We study the implications of quantum fluctuations of a dispersive medium, under steady rotation, either in or out of thermal equilibrium with its environment. A rotating object exhibits a quantum instability by dissipating its mechanical motion via spontaneous emission of photons, as well as internal heat generation. Universal relations are derived for the radiated energy and angular momentum a...

In this paper, we consider the time-dependent Maxwell’s equations when Cole–Cole dispersive medium is involved. The Cole–Cole model contains a fractional time derivative term, which couples with the standard Maxwell’s equations in free space and creates some challenges in developing and analyzing time-domain finite element methods for solving this model as mentioned in our earlier work [J. Li, ...

In this paper, we address the issue of collaborative information processing for diffusive source localization and tracking using wireless sensor networks (WSNs) capable of sensing in dispersive medium/environment. We first determine the space-time concentration distribution of the dispersion from physical modeling and mathematical formulations of an underwater oil spill scenario considering the...

A robust and high-resolution 2-D imaging algorithm is proposed for retrieving the shape of conductive objects embedded in a uniform lossy and dispersive medium. The target is modeled in terms of the location of of points which represents the outer contour of the object together with the parameters of the medium. A nonlinear least squares fitting is applied to the estimated scattered waveform to...

Conventional Time-Frequency and Time-Scale Representations are often too rigid to capture fine details of sound or musical signals. Adaptation of ideal time-frequency tilings is often desirable in order to represent the signal in terms of components that are meaningful from a physical or perceptual point of view. Remapping of the time and frequency axes by means of time and frequency warping ca...