根据盘荷加载慢波结构的色散关系,设计了C波段高功率行波结构放大器,器件采用轴向微波功率提取降低输出端的反射,并在隔离段中加入微波吸收体切断放大器中自激振荡的正反馈过程,输出腔采用锥形过渡以降低Q值,减少电子注回流,有效抑制了放大器中自激振荡。在2.5维PIC模拟中得到功率890 MW、频率5.64 GHz的微波输出,增益35.6 dB,效率32%。

A C-band relativistic traveling-wave-structure amplifier is designed from dispersion relation of disk-loaded slow-wave structure. In order to avoid self-excitation of the amplifier,some methods are employed in the tube design as follows: coaxial extraction to suppress reflection,sever and absorber to reduce substantially positive feedback,tapering output to reduce retrograde electrons. On the basis of cold cavity characteristic research,quantitative analysis of beam-wave interaction is performed using 2D PIC simulation code. The highest output power,the gain and efficiency is about 890 MW,35.6 dB and 32% respectively for a 5.64 GHz,250 kW input.