Influence of Shadowing Aperture by the Focal Module on Directional Characteristics of Reflector Antennas

The present report aims to research the influence of the sizes of an irradiator on directivity, width of the main lobe and a level of side lobes of the sharp directional parabolic reflector antenna pattern. The analysis of directional characteristics of reflector antennas with big diameters of radiating aperture and other focal lengths results to the following important conclusions for practice: long focus reflector antennas are more wideband on gain and width of the main lobe than shortfocus; the more F/D, the less relative influence of shadowing on factor of gain and width of the main lobe; - the more F/D, the greater level of the maximal side lobe (both the minimal and average for any d/lambda); the more F/D, the more narrow the main lobe of the pattern.