Ka波段二次谐波损耗波导回旋行波管非线性分析

 建立了由损耗段和铜段组成的波导结构的Ka波段二次谐波回旋行波放大器理论模型，并进行了非线性理论研究。基于稳定性分析，确定35 GHz TE₀₂模二次谐波回旋行波放大器的基本工作参数:波导半径为1.02 cm，电子注工作电压为90 kV，工作电流为25 A，工作磁场为0.642 6 T，横纵速度比为1.2；然后通过模拟详细分析了工作电流、波导损耗和速度零散等因素对该放大器性能的影响。研究表明：在该结构中损耗段可以有效地抑制模式竞争从而提高输出功率和带宽；工作电流对输出功率的影响存在最大值；速度零散对输出功率有很大的影响。

Nonlinear analysis of a Ka-band second harmonic distributedloss gyrotron traveling wave amplifier

The nonlinear theory of the Ka-band second harmonic gyrotron traveling wave amplifier with two-stage loss waveguide was studied. The two-stage loss waveguide consisted of a loss waveguide and a copper waveguide. The operating parameters of the 35 GHz TE02 mode second harmonic gyro-TWT were determined by stability analysis, and the radius of the waveguide is 1.02 cm, the working voltage of electron beam is 90 kV, the working current is 25 A, the magnetic field is 0.642 6 T, and the transverse-longitudinal velocity ratio is 1.2. The effect of several factors on the amplifier performance, including operating current, waveguide loss and velocity spread, were analyzed through simulation. The results show that the loss waveguide can effectively restrain the unwanted modes in this structure, thus