Abstract: Only when the resonant cavity of Microwave Plasma Thruster (MPT) is under the resonant state, the microwave energy can heat propellant gas to produce thrust efficiently. According to the test method on the return loss of passive parts of microwave apparatus, the resonating state of MPT cavity is experimented with the scalar network analyzer operating under low signal. Purpose is to analyze its energy absorbing efficiency and resonant frequency band, research the matching of the cavity dimension, microwave coupling probe position and the isolate plate material within the cavity. The conclusions are helpful for the thruster design and improving the system efficiency

Key words: Microwave plasma propulsion;Cavity resonator;Resonant vibration;Debugging

摘要： 微波等离子推力器(MPT)谐振腔只有在谐振状态下,微波能量才能被高效地用于加热工质产生推力。利用标量网络分析仪,采用微波无源器件回波损耗的测试方法对MPT谐振腔进行了精确地调谐,分析微波能量的吸收效率及谐振频率带宽,研究腔体的尺寸、微波耦合探针位置以及腔内的隔板材料等在同一谐振频率条件下的匹配性。调试结果可为腔体设计与提高系统效率提供参考。

关键词: 微波等离子推进;谐振腔;谐振;调试