Design of Input and Output Couplers of 18-40GHz Millimeter-wave Traveling-Wave Tube

The input and output couplers have been designed for 18-40 GHz millimeter-wave traveling-wave tube (TWT). The Ansoft's high frequency structure simulator (HFSS) simulation results show that the maximum voltage stand wave ratio (VSWR) for output coupler over 18-40 GHz is 1.8 and the maximum VSWR for input coupler is 1.7, fulfilling the design requirement. In consideration of the facility of fabrication technology, the input and output couplers are carefully designed and optimized.