并行多注THz折叠波导行波管的理论分析与数值模拟

Theoretical analysis and numerical simulation of parallel multi-beam THz folded waveguide traveling-wave tube

为了提高THz行波管的输出功率,通过并行多注和功率合成的方法,完成了并行多注D波段折叠波导行波管的理论分析与数值模拟。计算结果表明:单束行波管在0.135～0.157THz频率区间具有很好的色散平坦度,3dB带宽为13GHz,0.14THz处获得了20.88dB的最大增益;多束合成行波管在0.14THz处获得了20.8dB的合成增益,3dB带宽区间合成效率不低于92%。数值模拟表明该方法很好地实现了多路放大信号的合成输出。并行多注行波管具有输出功率大、单束电流小、聚焦磁场低等优点,能够在低发射电流密度条件下实现大功率THz辐射。

In order to increase the output power of THz traveling-wave tube（TWT）, by parallel multi-beam and power com- bining method, theoretical analysis and numerical simulation of parallel multi-beam D band folded TWT waveguide have been done, and simulation results demonstrate that the method can achieve the power combining output of multi-amplified signals. The results show： the single-beam mode TWT owns flat dispersion characteristics between 0. 135 THz and 0. 157 THz. The 3 dB gain band is 13 GHz and the largest gain is 20.88 dB at 0.14 THz. The multi-beam mode TWT got 20.8 dB combining gain at 0.14 THz and the combining efficiency is not below 92% in 3 dB gain frequency range. The parallel multi-beam mode TWT has many merits, such as high output power, small single-beam current and lower focusing magnetic field. The study helps achieving high power THz radiation basing on the present heat cathode level.