Aperture Eigenoscillations of a Plane Junction of a Circular Waveguide with a Set of Rectangular Waveguides

Aperture eigenoscillations of a plane junction of a circular waveguide with a set of rectangular waveguides have been studied. They play a decisive role in generation of eigenoscillations of more complex waveguide components, which include considered plane junctions. It is shown that the real part of the frequency of an eigenoscillation can be reduced by increasing the number of rectangular waveguides arranged in compliance with rotational symmetry and/or their widths. The eigenoscillation can be shifted below cutoff of the circular waveguide in the case of two wide rectangular waveguides. It is shown that when rectangular waveguides are arranged along concentric rings, the number of eigenoscillations increases with an increase in the number of rings. In connection with research in nanoelectronics and metamaterials, where many effects arise in structures with holes of complex configuration, it can be assumed that the explanation of many regularities can be found in the behavior of aperture eigenoscillations of the corresponding interfaces.