Calculation of the Half-Power Beamwidths of Pyramidal Horns With Arbitrary Gain and Typical Aperture Phase Error

This letter describes a method for calculating the half-power beamwidths of a pyramidal horn in closed form as a function of its gain and aperture phase error. The derived expressions are independent of the horn's physical dimensions and are valid for horns of arbitrary gain and phase error in the range of practical interest. Comparisons to methods in the literature demonstrate the efficacy of the approach. The formulation is a useful tool in the analysis and design of pyramidal horns when specific gain and half-power beamwidth values are required.