【摘要】 分析了单注折叠波导行波管增益和带宽的限制因素,提出了采用双注结构提高单位长度增益和拓宽带宽的方法。模拟结果表明,在工作电压和单注电流相同的情况下,采用同速双注(两电子注速度相同)可将高频互作用系统饱和输出功率提升至单注时的2.8倍,互作用效率提高了1.4倍,增益饱和长度缩短了5个几何周期;采用非同速双注可在更宽的频率范围内满足同步条件,展宽了带宽。设计了一工作频率为25~29.5 GHz的宽带折叠波导行波管,3 dB增益带宽可达到16.5%,约占冷带宽(12 GHz,22~34 GHz)的38%,输出功率在27 GHz时达到最大为256 W。另外,文中对由电路内部反射引起的增益不稳定性进行了分析,并给出了解决方法。更多还原

【Abstract】 A novel type of the two-beam Ka band folded waveguide of traveling wave tube(TWT)was developed to effectively relax the limitations on the gain and bandwidth.The conventional and newly-developed folded waveguide were modeled and simulated.The simulated results show that the two-beam folded waveguide outperforms the single beam folded waveguide in several ways.For example,an increase of the saturated power of high-frequency interaction by 2.8 times,an increase of the interaction efficiency by 1.4 times,and a reduction of the saturation length by 5 geometrical periods.Besides,the two beams at different speeds are capable of widening the synchronization frequency range,significantly easing the limitation on the bandwidth.We found that the saturated radiation power reached 256 W at 27 GHz.The 3 dB instantaneous bandwidth was 16.5%,covering the 25 ~ 29.5 GHz range.The possible ways to remove the negative effects of the internal reflection on instability of gain were tentatively discussed.更多还原