A Novel High-Power Rotary Waveguide Phase Shifter Based on Circular Polarizers

Abstract

This paper presents a novel high-power rotary waveguide phase shifter based on circular polarizers specifically engineered for high-power microwave (HPM) applications. The phase shifter is capable of performing a precise 360° linear phase shift through rotation and consists of three parts: a linearly polarized to left-handed circularly polarized (LP-LHCP) mode converter, a left-handed to right-handed circularly polarized (LH-RHCP) mode converter, and a linearly polarized to right-handed circularly polarized (LP-RHCP) mode converter. This paper analyzes the phase-shifting principle, optimizes the three parts of the X-band rotary waveguide phase shifter, and conducts simulation studies on the entire phase shifter, which is made of aluminum. The results show that the reflection is less than −20 dB and the insertion loss is below 0.3 dB within 9.5 GHz to 10.2 GHz. The phase shift is equal to twice the rotation angle within this frequency range. Specifically, the phase shifter can achieve a linear phase shift of 360° when rotated from 0° to 180°, with a maximum deviation of less than 1.2°. Moreover, the power-handling capacity of the phase shifter in vacuum exceeds 242 MW. In the meantime, a prototype of a phase shifter was manufactured, and the experimental results are in good agreement with the simulation results.