Elaboration of the polarizer’s construction for work in Ka-band

Abstract

The problems of the polarizer`s construction over the basis of the circular waveguide for work in Ka-band are highlighted in the article. The purpose of the article is to establish the possibility of using the proposed design for the construction of high-tech Ka-band polarizers and to prove the correctness of analytical expressions for determining the structural dimensions by experimentally obtained characteristics. The analysis of the current decisions from the point of view of construction and technology is held. On the conclusion had been drawn more technological polarizer`s construction with the calculation of the main constructive sizes is proposed.Theoretical principles of construction and calculation of structural dimensions of the C and Ku ranges polarizersʼ phase-shifting sections are covered in detail in the works of modern researchers and tested on real devices. However, while constructing AFT elements designed to operate in higher frequency operating bands, such as the Ka-band (20/30 GHz), there are certain difficulties, the solution of which continues. In order to check the proposed decision, an experimental model of the polarizer was made and an investigation of the main characteristics corroborating the right theoretical assumption was held. For a practical study of the proposed design, a mock-up of a polarizer based on a round waveguide with an inner diameter of 11 millimeters was made. In the prototype, the rod structure was implemented in the form of five pairs of adjusting screws with a diameter of one millimeter. The final length of the polarizing plate, taking into account the smooth transitions designed to align the plate with the waveguide, was defined as the sum of the lengths of its regular part and one smooth transition multiplied by 0.9. The experimentally obtained characteristics confirm the possibility of using the proposed design for the construction of high-tech Ka-band polarizers, and the correctness of analytical expressions for determining the structural dimensions. Further development of the proposed solution may be the analysis and finding the necessary analytical relationships between the structural dimensions of the rod and dielectric structures in order to expand the operating range of the polarizer.