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Dielectric-induced surface wave radiation loss.

ABSTRACT: We investigate a model which shows how the introduction of a perturbing dielectric close to an electromagnetic surface wave leads to radiation away from the surface through the dielectric. This resembles a surface waveguide passing through a wall or being deployed underground. Our theory, which is based on the mode-matching technique, allows quantitative determination of losses from a bound surface wave mode up to the point of its complete extinction. For a surface wave supported by a coated, conducting sheet the attenuation due to the perturbing dielectric is calculated for a number of frequencies, permittivities of the perturbation and separations between the sheet and the perturbing dielectric. The accuracy of our results is verified by simulation of the system with a full-wave numerical solution. Finally, we report experimental data of perturbed surface waves on a cable, which are in qualitative agreement with our model.

SUBMITTER: Schaich T

PROVIDER: S-EPMC7209143 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Dielectric-induced surface wave radiation loss.

Schaich Tobias T Al Rawi Anas A Morsman Trevor T Payne Mike M

Proceedings. Mathematical, physical, and engineering sciences 20200408 2236

We investigate a model which shows how the introduction of a perturbing dielectric close to an electromagnetic surface wave leads to radiation away from the surface through the dielectric. This resembles a surface waveguide passing through a wall or being deployed underground. Our theory, which is based on the mode-matching technique, allows quantitative determination of losses from a bound surface wave mode up to the point of its complete extinction. For a surface wave supported by a coated, co ...[more]

PMID: 32398941

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