Simulation Investigation of Novel Waveguide Phase Shifters for High Power Applications

High-power phase shifter that can adjust the transmit phase of high-power microwave (HPM) on-line is of great interest. It has an extensive application in mode converter, high power array antenna and other fields. However, the traditional phase shifters cannot satisfy the power capacity requirement. There is a pressing need to come up with new alternative phase shifters. In this paper, three kinds of waveguide phase shifters are investigated. To increase the power capacity, no dielectric is introduced, and they are all mechanical phase shifters. The first one named waveguide-inserting-fin phase shifter. The inserting-fin changes the transmission constant of the microwave. 360° phase shift can be obtained by adjusting the length of the inserting metal fin. The advantage of this phase shifter is that the microwave propagation keeps on the same direction but with longer longitudinal length. The second one named narrow side slot-waveguide phase shifter. It is designed based on 3 dB power divider of waveguide Slot Bridge. The difference is using adjustable metal choke plunger at the terminal position of the power divider. Then, it can realize 360° phase shift by adjusting the choke plunger position. The last one named folded rectangular waveguide phase shifter. It includes E-bend phase shifter and H-bend phase shifter. The output phase is changed by adjusting the position of the bend waveguide. The advantage of this phase shifter is that it can achieve 360 phase degree with smaller size. All the phase shifters are with high transmission efficiency over 99 % and high power capacity over 50 MW in the vacuum.