Analysis of loop antenna with circular reflector and its properties

The method of equivalent edge currents is applied to derive diffraction fields by an edge of a cone conductor. Geometrical-optical fields (direct wave + reflected wave) are added to the diffraction fields and both fields are Fourier analyzed to find current distirbutions and input impedance. Radiation pattern and power gain are obtained in terms of diffraction coefficients derived by Kouyoumjian et al. Calculations are made mainly for a one-wavelength loop antenna and the effects of the disk reflector diameter and wedge angle are clarified. The power gain is 1 dB larger than that of an infinite plane reflector. Theoretical results generally agree with observations.