Equivalent Circuit for High Efficiency Energy Transmission Matching Structure of Traveling Wave Tube: A Simulation Study

The energy transmission matching structure,with a matching-cylinder connected at one end of the helix traveling wave tube(TWT),was theoretically analyzed,empirically approximated,mathematically formulated with π-type equivalent circuit model,simply comprising 2 capacitors and 3 inductors,and numerically simulated with HFSS and ADS software for design optimization of the matching cylinder.The influence of the geometry and frequency of the matching cylinder on the transmission behavior was investigated.The preliminary simulated results show that the equivalent circuit model does a good job in description of the transmission characteristics of high efficiency energy transmission matching structure in 10~26 GHz band and in design optimization of the matching cylinder.We suggest that the newly-developed equivalent circuit model be of some technological interest in design optimization of TWTs.