Showing papers by "Juan Luis Cano published in 2021"

On the Accurate Full Characterization of Septum Polarizers Through Simple Amplitude Measurements in Back-to-Back Configuration

Abstract: This article introduces an easy and accurate technique for the full characterization of septum polarizers (SPs) in back-to-back configuration through standard amplitude/power measurements at the rectangular waveguide ports. The proposed calibration algorithm, based on the use of two simple waveguide sections, along with the developed mathematical formulation, allows the complete extraction of the relevant SP parameters: return loss, isolation, cross-coupling (XP) or axial ratio (AR), and copolarization losses (CP). The methodology has been successfully validated for two different designs at Ku -band.

Controlled Excitation of Waveguide High-Order Modes for a Simple and Accurate Monopulse Tracking System Test Bench

Abstract: Monopulse tracking systems require a calibration procedure, which is typically performed using a calibration tower or a known satellite, leading to high costs, antenna downtime, and potential inaccuracies. This work proposes a simple circular waveguide component, based on a step junction, able to excite high-order modes (HOMs) in a controlled way, so as to mimic the modes generated by the tracking antenna. This allows testing in laboratory the tracking system, avoiding the drawbacks of the traditional techniques. The theoretical working principle of the step-waveguide junction is discussed and an analytical model for the quick calculation of the offset between the two waveguides to achieve a desired HOM excitation coefficient is derived. Then, a Ku -band mode exciter is designed and its effectiveness is proved in conjunction with a designed TE21 tracking coupler. Finally, the fabrication and experimental validation of a prototype is reported, demonstrating the claimed performance.