POLARIZER ON A SECTOR WAVEGUIDE PARTIALLY FILLED BY DIELECTRIC

In the article a polarizer based on a sector waveguide partially filled by dielectric is studied. The design of a polarizer based on a sector waveguide with smaller dimensions of the dielectric plate and a better coefficient of the standing wave rectangular waveguide - polarizer on sector waveguide - rectangular waveguide junction compared with rectangular waveguide-polarizer based on a circular waveguide -rectangular waveguide junction has been developed. The diagrams of the articulateon of the waveguide segments of the antenna-feeder path on rectangular waveguides with a polarizer on a sector waveguide and with a polarizer on a circular waveguide are shown. Formulas for the propagation constant of a sector waveguide partially filled with a dielectric and the effective permittivity of a sector waveguide are given. The dependences of the relative permittivities of a waveguide with a sector dielectric plate parallel and perpendicular to the plane of polarization of the incident wave on the average thickness of the sector dielectric plate are presented. The paper analyzes a sector waveguide partially filled with a dielectric, which has휃=휋/3 и 훷=휋/6. In this case, the scalar eigenfunction of the sector waveguide for the quasi-퐻ଷଵ wave is used. The corresponding dependences of the change in the differential phase shift in the considered wave range on the average thickness of the sector plate are presented. At small thicknesses of the phasing plates the decrease in the polarizer broadband is due to an increase in the phase shift in the long-wavelength part of the range and at large thicknesses in the short-wavelength one. By choosing the permittivity of the material, it is possible to increase the broadband of the polarizer at the expense of some increase in the length of the plate. The dependence of the standing wave coefficient of the junction rectangular waveguide - polarizer - rectangular waveguide on the value 휆/휆଴. The standing wave coefficient for the junction of rectangular waveguide - polarizer on a sector waveguide - rectangular waveguide is 3...5 % less than for a junction of rectangular waveguide - polarizer on a circular waveguide - rectangular waveguide. A polarizer based on a sector waveguide with a dielectric plate has an advantage over a polarizer based on a circular waveguide with a dielectric plate when building antenna-feeder paths on rectangular waveguides. This advantage consists in achieving a lower value of the standing wave coefficient on the waveguide section of the path with a polarizer and a shorter length of the dielectric plate – 1,25휆଴.