Wave Matrix Technique for Waveguide Iris Polarizers Simulation. Theory

Abstract

Today polarization-processing devices are widely used in satellite information systems. Waveguide polarizers are the key element of antenna systems used to convert signal polarization from linear to circular type and vice versa. The circularly polarized signals have many significant advantages over the signals with other types of polarization. Consequently, simultaneous application of polarizers with other radio signal processing devices highly increases the efficiency of new satellite information and telecommunication systems for various purposes, wireless data transmission systems, mobile communication systems, radar systems and medical diagnostic systems. In this article, we have developed a new matrix technique for the calculation of parameters and characteristics of a polarizer based on a square waveguide with three irises, which are inductive or capacitive loads depending on the wave's polarization. Based on the theory of microwave circuits, the analytical expressions of the general wave scattering matrix were derived using the transmission and scattering wave matrices of elements of a polarizer structure. As a result, the main characteristics of the polarizer were obtained: differential phase shift, voltage standing wave ratio for vertical and horizontal polarizations, axial ratio and cross-polar discrimination. The presented method makes it possible to study the influence of the polarizer dimensions, such as the heights of the irises and the distances between them, on its main characteristics. Obtained analytical model makes it possible to find theoretically optimal sizes, which provide the required polarization characteristics of the device with the best matching in the operating frequency band. In addition, the developed wave matrix technique can be applied for further optimization using the specialized programs for microwave device simulation.

Analytical modeling and optimization of new Ku‐band tunable square waveguide iris‐post polarizer

“…The initial values for the optimization process are selected from the following expressions, applying the techniques from 17,82‐84 …”

Waveguide Slot Feed Section for Antennas with Circular Polarization

“…Далі з'явилися хвилеводні поляризатори на основі реактивних елементів у вигляді індуктивних та ємнісних діафрагм [17]- [23]. Сьогодні існує велика кількість методик з розрахунку поляризаторів з діафрагмами [24]- [29]. Крім того, поширеними є конструкції з діафрагмами у вигляді щілинних структур [30], [31].…”

Broadband Iris Polarization Converter for Reflector Antennas

“…Typically, polarization transformers and orthomode transducers are based on circular and coaxial waveguides [41], and square waveguides [42][43][44][45][46][47][48][49][50][51][52][53][54][55]. The main advantage of the iris polarization transformer is its most wideband operation compared to other designs.…”