Power loss and local surface impedance associated with conducting rough interfaces

Abstract

SUMMARYThe increase of the working frequencies of electromagnetic wave circuits causes high transmission losses due to the roughness of the metal surfaces. To understand this phenomenon, we model a rough metal interface in the simplest manner, by periodic grooves of infinite length. Then the reduced two-dimensional problem is analyzed numerically by the equivalent source method. Two polarizations are treated separately: the H-wave case, in which the directions of grooves and current are perpendicular, and the E-wave case, in which they are parallel. Three crosssectional shapes of the metal surface-rectangular, triangular, and semielliptical conductors-are selected for computing the power losses and local surface impedances. We observe how the shape and groove depth affect the above characteristics, and investigate the behavior of the numerical results physically by taking account of the field distributions.

Attenuation in Extended Structures Coated With Thin Magneto-Dielectric Absorber Layer

“…In the other words, the presence of a thin magneto-dielectric layer upon a conductor surface contributes to the degradation of its effective conductivity. This is analogous to the power loss due to rough conductor interfaces [23][24][25][26].…”

Silver nanopillar coatings grown by glancing angle magnetron sputtering for reducing multipactor effect in spacecrafts

“…Roughness reduces intrinsic (or flat mode) SEY by capturing part of the emitted electrons [15,16]. However, surface roughness of high aspect ratio present a new problem: the associated increase of RF surface resistance due to the skin effect of high-frequency electromagnetic waves [17,18], thus incrementing the RF power loss 4 (insertion loss) of the device and limiting its efficiency. This drawback is becoming more demanding with the requirement of increasing frequency in space technology.…”

Electromagnetic power absorption due to bumps and trenches on flat surfaces

“…Despite extensive usage, the frequency regime of validity for this scaling relation is not fully determined as yet. 5 Recently, both periodic 28,29 and random 16 roughness profiles have been studied using various methods. Holloway and Kuester 28 calculated the power loss associated with periodic conducting and superconducting rough interfaces using a generalized impedance boundary condition.…”

“…However, the fine details of the field near surfaces are not resolved. Matsushima and Nakata 29 utilized the equivalent source method to numerically study periodic rectangular, triangular, and semielliptical grooves both transverse and parallel to current flow. There are also studies on modeling the surface roughness with randomly distributed bosses on surface.…”