MULTIBAND PIRAMIDAL HORN ANTENNAS WITH IDENTICAL MAIN LOBE WIDTHS OF THE DIRECTIONAL PATTERNS

摘要

Directional patterns of compound multiband antennas in the form of open ends of square waveguides and pyramidal horns coaxially nested in one another are calculated. To ensure operation in the orthogonal linearly polarized basis each of the frequency channels is excited independently by a rectangular waveguide of the standard transverse cross-section. It is shown that identical main lobe widths of the directional pattern for each of the frequency channels can be realized for the operation wavelength ratio for adjacent channels exceeding 1.6. Blockage of the antenna aperture middle part by feed elements of the high-frequency channels results in increasing the side lobe level, which effect is the larger the smaller the operation wavelength ratio and the narrower the main lobe width.