Magnetic Current Approximation along the Waveguide Narrow Slot by the System of Two Functions Accounting for the Excitation Field Structure

Abstract

Admissibility of approximation of magnetic current distribution along the waveguide narrow slot by two functions accounting for the excitation field structure is studied. A longitudinal slot in a hollow and a partially filled with dielectric rectangular waveguides is considered. Such approximation is shown to be used to calculate the slot frequency characteristics within the whole waveguide operating frequency range provided an electrical slot length never exceeds at its upper frequency limit the value of 2l/λ=2.5 for a hollow waveguide and that of 2l/λ=2 for a partially filled waveguide at delay ratios 1< λ/λ_g ≤1.3.