Sistema de alimentación de antena en guía de onda y banda-Ka para aplicaciones de polarimetría

Abstract

This paper presents the design and measurement results of different waveguide hardware designed for an antenna feed system intended for polarimetry applications in the Ka-band (26 – 36 GHz). The proposed structure, based on a square-waveguide polarizer followed by an orthomode transducer, represents an alternative to the classical setups using septum polarizers, improving their achievements in terms of bandwidth. Due to the low polarization levels and the relatively large polar foregrounds to be detected, the subsystems must exhibit a great performance, minimizing cross-polarization effects and leaks between signal components. The designed corrugated feedhorn has a measured cross-polarization around -40 dB, whereas the polarizer axial-ratio is below 0.15 dB and the orthomode transducer isolation is better than 50 dB.