40~50 GHz宽带螺旋线行波管高频系统研究

Research on High Frequency Structure of 40~50 GHz Broadband Helix Traveling Wave Tubes

针对40 GHz以上电磁兼容试验需求,开展了40~50 GHz宽带螺旋线行波管研制。本文主要对该行波管的高频系统进行技术研究。通过尺寸共度效应理论分析和螺旋线表面镀膜降低高频衰减技术,研究了高频率行波管的色散特性、耦合阻抗、高频衰减、横向传播常数等高频特性的变化规律。采用无翼片加载慢波结构、螺旋线双渐变技术和衰减器分布优化设计方法,提高了宽带输出功率和电子效率,同时抑制了返波振荡。研制出的行波管在40~50 GHz范围内,饱和功率达到110 W,能够满足宽带毫米波电磁兼容试验的需求。

To meet the electromagnetic compatibility(EMC)test requirements over 40 GHz,40~50 GHz broadband helix TWT is developed at BVERI.The high frequency structure of the TWT is mainly studied.Based on wavelength-size-matching effect of linear-beam tube and the helix surface-coating to reduce high frequency attenuation,the dispersion,coupling impedance,high frequency attenuation and radical propagation constant of the slow wave structure are analyzed and simulated.The vaneless slow wave structure,helix double-tapering method and optimal design of attenuators distribution are adopted to improve the broadband output power and electronic efficiency,and meanwhile to suppress backward wave oscillation.The developed TWT has a saturated output power of 110 W in the frequency range of 40~50 GHz and can meet the needs of broadband millimeter wave EMC tests.