On the electromagnetic power transmission between two lossy media: discussion

Abstract

An overview of the problems involved in the study of electromagnetic power transmission between lossy media is presented. Starting from the well-known problem of the transmission at a dielectric-conductor interface, the different representations of the complex propagation vector of the plane waves are introduced. Analytical expressions to convert from one formulation to the other are obtained. Moreover, the transmission of a plane wave at the interface between two lossy media is taken into account. An explanation of the strange behavior of the transmitted wave is developed by means of power considerations. Finally, the interesting effect of the parallel-attenuated transmitted wave is presented, and its properties as a function of the incident phase vector amplitude are deduced.

Analytical Investigation on a New Approach for Achieving Deep Penetration in a Lossy Medium: The Lossy Prism

“…Let us now define with ξ 1 the angle that the phase vector of the incident wave β 1 forms with the normal to the interface between air and lossy medium. The theory developed in [4], [6] demonstrates that, when ξ 1 is smaller than or equal to 45 • it is possible to find a critical value β 1c for the amplitude of β 1 such that the angle ζ 2 formed by α 2 with the normal to the separation surface is 90…”

Numerical Evaluation of Electromagnetic-wave Penetration at Normal Incidence through an Inhomogeneous-wave Approach

“…In [1] and [2], the deep-penetration condition is verified from an analytical-theoretical point of view, and in [5] preliminary results demonstrate that the deep-penetration condition can be met employing simple uniform leaky-wave structures such as the Menzel antenna [22], [23].…”

“…Finally, it was important to verify the property demonstrated for plane waves in [1], [2] for which a larger incidence angle would result in a deeper penetration in a lossy medium through inhomogeneous waves. As the twodimensional patch LWA presents a very low amplitude of the attenuation vector α α α, it follows that the best penetration condition is guaranteed by an incidence angle ξ 1 = 45 • .…”

“…Such a problem represents a typical air-coupled antenna scenario. In [1], [2], authors found analytical requirements and restrictions of the so-called "deep-penetration" condition. The problem studied in such papers is the incidence of an inhomogeneous plane wave, incoming from a lossless medium, on a planar and infinite separation surface with a lossy medium.…”

“…It was observed that leaky-wave antennas [3], [4] can be employed to generate an electromagnetic field suitable for deep penetration in near-field [5]. Moreover, it was demonstrated in [1], [2], that the deeppenetration condition can only be obtained for oblique incidence. Such a condition, as highlighted in [6], is not very practical for many applications, where, instead, normal incidence is recommended.…”