Compact Polarizers for Satellite Information Systems

Abstract

This paper presents results of development and analysis of new Ku-band compact polarizers based on a square waveguide with irises. Main advantages of electromagnetic waves with circular polarizations, which are obtained in satellite antenna systems with polarizers, are listed and discussed in the article. The designs of compact waveguide polarizers with 3, 4 and 5 irises have been optimized to provide effective polarization and matching performance in the operating Ku-band 10.7-12.8 GHz. The dependences of electromagnetic characteristics of polarizers on frequency were simulated and optimized using finite integration technique. The alteration of sizes of optimal structures and improvement of their characteristics have been analyzed for the polarizers with number of irises from 3 to 5. The best performance among the considered designs is provided by the square waveguide polarizer with 5 irises. Voltage standing wave ratios of the polarizer with 5 irises for both linear polarizations are less than 1.13. The optimized differential phase shift lies within the range $90^{\circ}\pm 2.6^{\circ}$. The axial ratio of the polarizer with 5 irises is less than 0.40 dB. The XPD is higher than 32.9 dB. Therefore, developed new compact square waveguide polarizer with 5 irises provides efficient performance in the operating Ku-band 10.7-12.8 GHz and can be widely used in modern satellite television and other information systems.