High-power waveguide phase shifters for phased array applications

Two kinds of high-power waveguide phase shifters targeting the application of phased arrays are proposed in this paper. To enhance the power handling capacity, both linear phase shifters are designed to be mechanically tunable without the introduction of a dielectric and a semiconductor. For the waveguide-inserting-fin phase shifter, the phase shifting function is achieved by adjusting the length of the inserting metal fin. As for the narrow-side slot-waveguide phase shifter, the regulation of the position of the metal choke plunger placed at the end of the 3-dB power divider is used to adjust the output phase. The simulation results show that both phase shifters can realize 2π phase shift, and the transmission efficiencies are over 99% at the central frequency of 9.5 GHz. Meantime, the power handling capacity of the designed shifters is expected to be over 100 MW, which can be applied in the high-power microwave region. The slot-waveguide phase shifter is fabricated and tested along with the slotted array antenna. The experimental results coincide well with the simulations, which demonstrates the feasibility and the power capacity of the designed shifter.