300GHz折叠波导行波管高频结构的设计与测试

Design and Cold Test of the High Frequency System for a 300GHz Folded-Waveguide Traveling Wave Tube

由于折叠波导具有全金属结构、功率容量大、易集成等特点,非常适合在太赫兹频段推广应用。本文针对300GHz折叠波导行波管进行设计并加工。文中主要对工作频率在300GHz附近的折叠波导的色散特性、耦合阻抗、损耗特性及其折叠波导行波管的注-波互作用进行研究和仿真。在电压为18.4kV、电流为8mA、功率为5mW、频率范围在301～308GHz、周期数为200时,该行波管的增益约为20dB。对该折叠波导进行加工,通过矢量网络分析仪测得折叠波导成品S参数,验证了加工技术和装配方式。

The folded waveguide can be applied into THz band because of enormous advantage, such as all-metal construction, higher power capacity and ease of integration. In this paper, we design and process a 300 GHz traveling wave tube (TWT) adopting a folded waveguide structure. We mainly study and simulate the dispersion characteristics, the coupling impedance, the loss characteristics and the beam-wave interaction of the folded waveguide traveling wave tube. The gain of TWT is about 20 dB under the voltage of 18.4 kV, the current of 8 mA, the input power of 5 mW during the frequency range of 301~308 GHz with the circuit period number of 200. We manufacture the folded waveguide and measure its S -parameter by vector network analyzer to evaluate the fabrication technology and assembly method.