A High-Speed Numerical Analysis Technique for Millimetre Wave Aperture Antennae

Abstract

By use of the geometrical theory of optics the radiation characteristics of a WGM antenna have already been investigated and designed. In order to improve the accuracy of the present calculation it was necessary to account for diffraction. Since the conventional method based on Kirchhoff-Huygens principle requires much computational time and memory, a numerical analysis method has been developed to overcome such a difficulty, i.e. the antenna aperture is subdivided into a series of subapertures of small area so that the field amplitude can be assumed uniform with the phase either uniform or linearly changing. The radiation fields from the subapertures are evaluated by use of an appropriate analytical solution. The radiated field pattern of the aperture is subsequently obtained by summing the radiation contributions from each of the subapertures in turn. Results from the most recent WGM calculations will be presented.