Compact broadband planar orthomode transducer

TL;DR

This paper introduces a compact, broadband orthomode transducer for C-band applications, demonstrating high performance with low cross-polarization and minimal insertion loss across the WG13 band.

Contribution

The paper presents a novel design of a compact, broadband orthomode transducer with experimental validation showing excellent polarization isolation and low insertion loss.

Findings

Cross-polarisation level below -58 dB

Return loss of about -20 dB

Insertion loss difference less than 0.18 dB

Abstract

We present the design and test results of a compact C-band orthomode transducer which comprises four rectangular probes orthogonally arranged in a circular waveguide, designed to work in the WG13 band. Measurements of the system in the frequency range 4.64 GHz to 7.05 GHz agree very well with simulation results and show a cross-polarisation level below -58 dB, a return loss of about -20 dB, and an insertion loss difference of less than 0.18 dB between the orthogonal polarisation modes across the full waveguide band.