Small-signal analysis of a rectangular helix structure traveling-wave-tube

• 来源期刊: 中国物理B（英文版）
• 关键词: rectangular helix small-signal gain slow-wave structure compact TWT
• 年，卷（期）: 2009,（7）
• 页码范围: 2749-2756
• 页数: 8页
• 语种: 英文

摘要

This paper investigates the properties of traveling wave-beam interaction in a rectangular helix traveling-wave-tube (TWT) for a solid sheet electron beam. The 'hot' dispersion equation is obtained by means of the self-consistent field theory. The small signal analysis, which includes the effects of the beam parameters and slow-wave structure (SWS)parameters, is carried out by theoretical computation. The numerical results show that the bandwidth and the smallsignal gain of the rectangular helix TWT increase as the beam current increases; and the beam voltage not obviously influences the small signal gain. Among different rectangular helix structures, the small-signal gain increases as the width of the rectangular helix SWS increases, however, the bandwidth decreases whether structure parameters a and Lor ψ and L are fixed or not. In addition, a comparison of the small-signal gain of this structure with a conventional round helix is made. The presented analysis will be useful for the design of the TWT with a rectangular helix circuit.