Ku-band antenna array
linear orthogonal polarizations
K. K. Klionovski, А. S. Yakovlev
In this paper a construction of an antenna array, operating simultaneously with the signals of two orthogonal linear polarizations in the spatial frequency range 10,7-12,75 GHz is proposed. Antenna array is a multi-panel with radiators in the form of the open ends of the rectangular waveguide, and equipped with two network junction waveguide system. Between the radiators, which are the open ends of the rectangular waveguide, matching elements are made in the form of truncated pyramids. They provide a decrease in the amplitude of the wave reflected from the aperture radiator back into the distribution network. They also serve as horn, increasing the coefficient of directional radiation.
Constructed under the parallel type scheme of division junction waveguide system is a two-tier network of waveguides, each network consists of trunk and branch waveguides. The upper junction waveguide network is a collection of rectangular waveguides formed in the rear surface of the second layer and the front side of the third layer. The broad wall waveguide is oriented perpendicular to these layers. The lower waveguide network is located in the bottom two layers of the antenna, containing power splitters and matching elements - the diaphragm and the quarter-wave transformers.
For the antenna array, consisting of 25 × 21 emitters were calculated directional characteristics and matching. Overall dimensions of the antenna array are 550 × 467 × 42 mm. For a specified frequency range VSWR less than 1,5. Antenna gain for each of the linear polarization at a frequency of 10,7 GHz - higher than 34,3 dB, at a frequency of 12,75 GHz - higher than 36 dB. Losses in the path antenna – 0,3 dB/m. The antenna provides a high isolation of the polarizations (more than 30 dB).