A klystron-like relativistic backward-wave oscillator (KL-RBWO) with transverse electron beam confinement and waveguide reflection, which works well under a magnetic-field strength below that of the cyclotron resonance, is proposed. For this device operating with a low magnetic field, effective suppression of the transverse velocity of electron beams is introduced by a local electric field near the tube head, to promote modulation uniformity of electron beams. Part of the reflected microwave from the output waveguide provides feedback enhancement to the extractor, which strengthens the local standing-wave field. Owing to a stronger electric field that can interact with the electron beam in the extractor and a higher growth of fundamental harmonic current, the efficiency of the KL-RBWO is increased to 40% when guided by a magnetic field of 0.32 T, compared with that of 30% using conventional structures.

中文翻译：

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具有波导反射和聚束促进的类速调管相对论后向波振荡器的效率增强

提出了一种具有横向电子束限制和波导反射的类速调管相对论后向波振荡器（KL-RBWO），该振荡器在低于回旋共振的磁场强度下工作良好。对于这种在低磁场下工作的装置，通过管头附近的局部电场有效抑制电子束的横向速度，以提高电子束的调制均匀性。来自输出波导的部分反射微波为提取器提供反馈增强，从而增强了局部驻波场。由于可以与提取器中的电子束相互作用的更强电场和基波电流的更高增长，当由 0.32 T 磁场引导时，KL-RBWO 的效率提高到 40%，