Compact Posts-Based Waveguide Polarizer for Satellite Communications and Radar Systems

Abstract

In this study we have developed and optimized a new compact guide polarizer with metal posts for satellite communications and radar systems. Its novelty consists in the possibility of fine tuning of the characteristics. Suggested polarizer design consists of a guide with a square cross section and two metal posts, which are located in the center. The posts were simulated as cylindrical conductors. The main electrical parameters of the developed waveguide polarizer with posts were calculated using the equivalent circuit technique, the theory of scattering and transmission wave matrices and the finite difference time domain method. The plots of magnitudes and phases of all scattering parameters of the developed device were obtained and optimized in the operating satellite frequency range of 14-14.5 GHz. The proposed polarization converter allows to obtain output phase difference 90°±1.6° in the entire operating frequency range. Simultaneously, the peak value of a standing wave factor by voltage is less than 1.34 for both orthogonal linear polarizations. Computed peak value of the elipticity parameter is 0.26 dB. The values of the obtained discrimination of linear polarization are better than −37 dB. Consequently, the results of performed study can be widely applied for the engineering of modern microwave polarization conversion devices for satellite and terrestrial systems.