V波段微带线行波管慢波结构的设计

A Design of Microstrip Slow-Wave Structure for V-Band TWT

提出了一种新型的微带线慢波结构。与传统的N型微带线慢波结构相比,新型结构具有相速值较小、工作电压低、功率大、耦合阻抗高等特点。利用HFSS和CST分别对此结构在V波段进行高频特性、传输特性和注-波互作用仿真,得出在60GHz频点耦合阻抗大于20Ω,在55~63GHz频段内VSWR【1.5;当输入功率为100mW时,并且带状电子注的电流和电压分别工作在100mA和5kV的条件下,该行波管慢波结构的最大输出功率为115W,平均互作用效率为14.6%,瞬时3dB带宽为5GHz(56~61GHz)。

A novel microstrip meander-line slow-wave structure(SWS)is proposed for 60GHz traveling-wave tube(TWT).Compared with the conventional microstrip meander-line SWS,the new microstrip meander-line SWS has smaller phase velocity,lower operating voltage,high power and coupling impedance. The dispersion,coupling impedance,transmission characteristics and beam-wave interaction are simulated by HFSS and CST.The results show that the coupling impedance is greater than 20Ωin 60GHz and VSWR<1.5ranging from 55GHz to 63GHz.The calculation of beam-wave interaction indicates that, with beam current of 100mA and a beam voltage of 5kV,the new microstrip meander-line slow-wave structure is capable of delivering more than one hundred of watts output power.And its interaction efficiency reaches 14.6% with a transient 3dB bandwidth of 5GHz(ranging 56GHz to 61GHz).