Gain enhancement of circular waveguide antennas using dielectric disc

The directivity of a circular waveguide antenna has been enhanced by utilizing a dielectric disc in front of its aperture. The effect of different parameters on the antenna directivity was investigated. The waveguide is considered with or without a conducting flange. The analysis was carried out numerically using the method of moments to solve the surface integral equations for the unknown equivalent currents. It was found that the presence of the conducting image significantly enhances the antenna directivity.<
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