The advantages of using symmetrical and asymmetric eigenmodes of a slow-wave system (SWS) in a relativistic traveling-wave tube (TWT) with multi-pass amplification are discussed. The nonlinear theory of such a TWT amplifier is developed. The parameters of the SWS of the Ka-band TWT amplifier based on a combination of the lower symmetric E01 mode and the asymmetric hybrid HE11 mode are calculated. The calculated efficiency of the amplifier reaches 28% with a gain of about 40 dB. The results of the calculations are confirmed by 3D particle-in-cell (PIC) simulation, in which an output power of 200 MW and a total gain of about 40 dB are obtained when the amplifier is driven by a 500 keV/2 kA hollow electron beam with a total pulse duration of 25 ns. Amplification of short millimeter-wave pulses is also demonstrated in PIC simulations, in which an output peak power of about 180 MW with a pulse duration of the order of 1 ns is obtained.

中文翻译：

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对称和非对称模式同时工作的多通道相对论行波管

讨论了在具有多通放大的相对论行波管 (TWT) 中使用慢波系统 (SWS) 的对称和非对称本征模的优点。开发了这种 TWT 放大器的非线性理论。计算了基于低对称E01模式和非对称混合HE11模式组合的Ka波段TWT放大器的SWS参数。放大器的计算效率达到 28%，增益约为 40 dB。计算结果通过 3D 粒子内粒子 (PIC) 仿真证实，其中当放大器由 500 keV/2 kA 空心驱动时，获得 200 MW 的输出功率和约 40 dB 的总增益。总脉冲持续时间为 25 ns 的电子束。在 PIC 模拟中也证明了短毫米波脉冲的放大，