X-band mechanical waveguide switch with gap waveguide technology and its actuator mechanism

Abstract The design of double-pole double-throw (DPDT) and single-pole double-throw (SPDT) waveguide switches, along with their actuating mechanisms for high-power applications, is presented. The mechanical waveguide switch is based on gap waveguide technology, which uses a controlled air gap to prevent electromagnetic wave leakage. A rotating inner cylinder enables signal transmission and switching, while a fixed outer cube protects the cylinder and secures the input and output ports. Dividing the switch into two parts simplifies manufacturing and assembly. The switch can withstand a peak power of 100 kW. Its electrical performance is analyzed using CST Studio Suite. The proposed switch is fabricated and experimentally validated, showing strong agreement between simulated and measured results. The return loss exceeds 30 dB, indicating very low reflected power, while the insertion loss is below 0.1 dB, demonstrating minimal signal power loss. The isolation is greater than 90 dB, indicating extremely low leakage between ports. The switching operation is controlled by an actuating mechanism designed using COMSOL Multiphysics. The mechanism operates at 28 V and 0.9 A, achieving a switching time of 50 ms. The proposed design provides high-power handling capability, low loss, high isolation, and fast switching performance.