This article describes and evaluates the effect of random geometrical perturbations on resonance characteristics and output performance of extended interaction klystrons (EIKs). The perturbations, assuming a normal distribution, will result in random variation in resonance characteristics, including resonant frequency shift, quality factor shift, and field distortion. The results are demonstrated in a 220-GHz extended interaction cavity by combining theory, simulations, and experimental measurements. In addition, 3-D particle-in-cell (PIC) simulation and small-signal theory are employed to gain insights into the output performance instabilities caused by variation in the resonance characteristics. The comprehension of the factors that contribute to performance instability is fundamental to avoid excess costs in the fabrication process. Aided by the small-signal theory code with a calculation speed that is several orders faster than PIC simulation, we address the instability by applying cathode voltage adjustment technology, frequency tuning technology, and multiparameter optimization based on a genetic algorithm. Such analysis and improvement patterns are general for the EIKs operating in the terahertz regime.

中文翻译：

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具有随机几何扰动的扩展相互作用速调管性能不稳定性分析及改进,具有随机几何扰动的扩展相互作用速调管性能不稳定性分析及改进

本文描述并评估了随机几何扰动对扩展相互作用速调管 (EIK) 的谐振特性和输出性能的影响。假设为正态分布的扰动将导致谐振特性的随机变化，包括谐振频率偏移、品质因数偏移和场失真。通过结合理论、模拟和实验测量，在 220-GHz 扩展交互腔中展示了结果。此外，采用 3-D 细胞内粒子 (PIC) 模拟和小信号理论来深入了解由谐振特性变化引起的输出性能不稳定性。了解导致性能不稳定的因素对于避免制造过程中的额外成本至关重要。借助计算速度比PIC仿真快几个数量级的小信号理论代码，我们通过应用阴极电压调整技术、频率调谐技术和基于遗传算法的多参数优化来解决不稳定性。这种分析和改进模式对于在太赫兹范围内运行的 EIK 是通用的。,本文描述并评估了随机几何扰动对扩展相互作用速调管 (EIK) 的谐振特性和输出性能的影响。假设为正态分布的扰动将导致谐振特性的随机变化，包括谐振频率偏移、品质因数偏移和场失真。通过结合理论、模拟和实验测量，在 220-GHz 扩展交互腔中展示了结果。此外，采用 3-D 细胞内粒子 (PIC) 模拟和小信号理论来深入了解由谐振特性变化引起的输出性能不稳定性。了解导致性能不稳定的因素对于避免制造过程中的额外成本至关重要。借助计算速度比PIC仿真快几个数量级的小信号理论代码，我们通过应用阴极电压调整技术、频率调谐技术和基于遗传算法的多参数优化来解决不稳定性。这种分析和改进模式对于在太赫兹范围内运行的 EIK 是通用的。