Polarization signal processing is widely used in modern information and telecommunication systems for various purposes. Signal polarization processing is carried out in polarization-adaptive antenna systems. The key element of such systems is transformation devices for polarization processing. They perform the transformation of the types of polarization and separate the different types. The most commonly applied systems are the ones using a single circular polarization or two orthogonal circular polarizations simultaneously.The absence of the need for an accurate angle orientation between the transmitting and receiving antennas to establish communication is one of the basic advantages of this type of polarization. When using antenna systems with linear polarization, signal losses appear due to inconsistency in the orientation of the polarization planes of the transmitting and receiving antennas. This feature of circular polarization is important for satellite and many other telecommunications systems. In such systems it is difficult to maintain a fixed orientation of one antenna relative to the other. In addition, circular polarization is used to communicate with satellites orbiting the direction of the radio link. Regardless of antenna orientation, when using circular polarization, the received signal level is constant. These advantages explain why circular polarized antennas are widely used in radio engineering systems for various purposes. The paper presents the results of the development of a polarization device based on a square waveguide with two posts and two diaphragms in the frequency range from 7,7 to 8,5 GHz. The article contains the results of calculations using the developed mathematical model of the device. In addition, the results of modeling the device using the finite element method are presented for comparison. A comparison was made of the polarization characteristics and the match of the developed polarizer. The created mathematical model makes it possible to effectively analyze the characteristics when changing design parameters. These parameters include the size of the wall of the square waveguide, the heights of the diaphragms and pins, the distance between them, the thickness of the diaphragms and pins. The developed polarizer is suggested for the application in satellite telecommunication and radar systems.
Tunable square waveguide polarizer with irises and posts