Equivalent edge current technique for accurate determination of reflector antenna patterns

G. L. James and V. Kerdemelidis (1973) employed the equivalent edge current (EEC) technique to determine the radiation patterns of a paraboloid. Their computed results were found to have a substantial deviation from the corresponding measured results in the main beam or boresight direction. It is found that the reason for the disagreement in the boresight caustic region between the patterns computed using EEC and the patterns obtained by measurement is not due to the limitation of the EEC technique but to the model employed by James and Kerdemelidis. Their reflector antenna was modeled by a straight-edge, flat-plate geometry, whereas the correct model should use a straight-edge, curved-screen geometry. Thus, the validity of the EEC/UTD (uniform theory of diffraction) technique for determining the complete radiation pattern of a reflector antenna from a straight-edge, curved-screen model for the reflector surface is demonstrated.<>