Impedance characteristics of series slots

The nature of an equivalent network of slots having any arbitrary orientation in the broad wall of a rectangular waveguide, for both even and odd distributions of the aperture field, has been investigated. The complex power radiated by the slot has been determined from the angular spectrum of plane waves. The impedance characteristics of the transverse slot and of the centred inclined slot have been obtained from the complex radiated power and the discontinuity in the modal voltage, as well as from the scattering coefficients, using the energy balance equation. The impedance characteristics calculated by the two methods are identical. The theoretical results are in good agreement with experimental results.