On primary incident wave models for pyramidal horn gain calculations

A few widely used primary incident wave models for pyramidal horn antenna analysis are compared on the basis of gain calculations. The analysis is based on edge-wave diffraction theory, as presented in a previous publication, with some modifications made to the underlying theory. It is shown that these models agree well for high-gain horns with small flare angles, but that the differences are more profound for lower gain horns, where the flare angles are larger. The accuracy of the various models are studied by comparing the results to actual measurements. The respective effects of amplitude and phase variation in the primary incident wave are also illustrated.