Scattering of Electromagnetic Waves by Wires and Plates

The scattering of electromagnetic waves by wires and plates is discussed, particularly with reference to new polarization components which appear. An approximate solution is obtained for the problem of scattering of radiation by a rectangular plate, for arbitrary angle of incidence, and arbitrary direction of polarization. The problem of scattering by a wire is formulated in terms of the current distributions on the wire when center driven, and when driven as a receiving antenna. A relation between the magnitude of the input impedance of a center-driven wire and the scattering properties of the wire is given. The use of simple sinusoidal current distributions is shown to give good results for the scattering of wires of length less than a wavelength. The scattering properties of a wire are shown to provide a method for precisely measuring the magnitude of the input impedance of a center-driven wire. This avoids the problem of the input region susceptance which occurs when the antenna impedance is measured by means of a transmission line coupled to the antenna.