V. V. Biryukov, T. V. Kozhevnikova, S. G. Lobin

1–3  Nizhny Novgorod State Technical University n.a. R.E. Alekseev

The paper considers a method for taking into account the roughness of the conductive shielding surfaces of guide electrodynamic structures. A brief overview of the existing models of surface roughness has been presented and the calculation method based on the gradient model has been analyzed. The rough surface has been modeled by a layered structure, in which the characteristics of the layers change smoothly, successively passing from the parameters of the air to the parameters of the metal.

The reflection coefficient of an electromagnetic wave from such a layered structure has been found by the method of directed graphs, which allows us to take into account multiple reflections of waves from the boundaries of layers. The effective unit conductivity of a rough surface has been determined from the equality of the reflection coefficient from a rough surface and the reflection coefficient from a smooth surface.

Using the developed technique, the dependences of the effective unit conductivity of a rough surface on the size and profile of the roughness and on the frequency have been obtained. It has been shown what effect the height and profile of the unevenness of the shielding surface has on the effective unit conductivity of the shielding surface, and hence on the attenuation per unit length of the eigenwaves of the guiding electrodynamic structures.

Biryukov V.V., Kozhevnikova T.V., Lobin S.G. Determination of the effective specific conductivity of rough conductive surface.

Antennas. 2021. № 2. P. 30–34. DOI: https://doi.org/10.18127/j03209601-202102-04 (in Russian) 

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