In general, the problem of the excitation (radiation, scattering) of electromagnetic fields by a system of finite-dimensional material objects in arbitrary electrodynamic volumes is formulated. On the basis of the impedance concept, the problem is reduced to solving two-dimensional integral equations for electric surface currents on material objects. A physically correct transition from the obtained integral equations to a system of one-dimensional equations for currents on electrically thin impedance vibrators (monopoles) with electrophysical and geometric parameters that can be irregular along their length is made. As an example, a system of two monopoles with a variable surface impedance located in a rectangular waveguide is considered. The problem was solved by the generalized method of induced electromotive forces (EMF). A distinctive feature of this method is that the current distribution functions found by the asymptotic averaging method are used to solve integral equations for currents. The numerical and experimental results concerning electrodynamic characteristics of the structure under consideration are presented.
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