基于共振增强效应的带状注金属格栅波导放大器的研究

The sheet beam metallic grating amplifier can produce coherent electromagnetic radiation with the characteristics of high power, high frequency, and broad bandwidth, which make it demonstrate promising applications in scientific researches, military equipments, and industrial fields. Through the hybrid mode interacting with the cyclotron electron, the enhancement effect from the combination of the Cherenkov and the anomalous Doppler cyclotron resonances cam evidently improve the gain and bandwidth in the same system. This project focuses on this new interaction mechanism. By using the theoretical analysis, particle-in-cell simulation, and the experimental measurement, we will thoroughly investigate the feasibility of this scheme and obtain the realization techniques in engineering. This research is a fundamental work for developing the future high frequency electromagnetic radiation source. . The concrete research contents are briefly presented as follows. For the sheet beam metallic grating interaction system based on the resonance enhancement effect, we will find its operation mechanism in physics and exhibit its clear working process through the theoretical analysis and simulation. Employing the simulation and experiment, a planar symmetric magnetic injection gun with the excellent performance will be designed and built. Finally, a proof-of-principle device will be assembled in W-band to validate the feasibility of the resonance enhancement effect. The experimental phenomena will be explained through synthesizing the results of the previously developed theory and the relevant simulation. On the other hand, the experimental data will help to amend the theoretical model. This project can help us, to some extent, become familiar with the physical and structural design, the component manufacturing, and the experimental testing of such a novel device.

带状注金属格栅放大器能够产生高功率、高频率和宽频带的相干电磁辐射，这使其在科学研究、军事装备和民用领域均有着广泛的应用前景。通过混合模与回旋电子注互作用，利用契伦科夫共振和反常多普勒回旋共振的叠加增强效应，可使系统的增益和频带获得显著提高。本项目围绕这一新型互作用机理开展研究，通过将理论分析、模拟仿真和实验测试相结合，充分检验该方案的可行性并探索其工程实现方法。这项研究是发展新型高频率电磁辐射源的基础性工作。. 具体内容包括：针对基于共振增强效应的带状注金属格栅波导互作用系统，通过理论和模拟对其中的物理机理进行解释并获得清晰的物理图像；通过仿真和实验，研制出性能优良的平面对称磁控注入电子枪；在W波段制成原理性器件，对共振增强效应进行实验验证，结合理论与仿真对实验现象进行解释，并反过来完善理论模型。通过这项研究，初步掌握该新型器件的物理设计、结构设计、加工制造和实验测试方法。

本项目面向远距离通信、微波遥感和成像、雷达和电子对抗等领域对高功率、高频率、宽频带真空电子器件的需求，为发展新型毫米波及以上频段的带状回旋注金属格栅放大器探索新的多共振叠加互作用机理。取得的主要进展和结果简述如下。. 1) 通过分析回旋管中的绝热压缩理论和角动量守恒定律，推导出了平面结构磁控注入回旋电子枪基本参数的计算公式，并且总结出平面结构磁控注入回旋电子枪的基本设计步骤，对阴极关键参数的关系进行了数值模拟分析。. 2) 结合超导螺线管聚焦系统的相关理论，使用Opera电磁仿真软件设计出满足平面结构磁控注入回旋电子枪工作的聚焦系统。使用二维稳态软件EGUN和三维软件Opera完成了94GHz双阳极平面结构磁控注入回旋电子枪的设计。. 3) 采取理论分析、软件仿真相结合的方法对矩形栅慢波结构的冷色散特性进行分析，完善了格栅结构中关于TMx模式的研究内容，推导出矩形单栅慢波结构中的TEx和TMx模式的“冷”色散方程，计算表明空间谐波的归一化场幅值系数具有很好的周期性。. 4) 采用动力学方法，建立了二维TE和TM模式带状注矩形单栅回旋脉塞的线性理论，获得了互作用系统的“热”色散方程，该色散方程可以考虑组合共振的影响。当系统中同时存在多个共振且满足强谐振条件时，工作于TM模的组合共振的增益和带宽要比只存在契伦科夫谐振时的增益和带宽有所提高。. 5) 建立基于共振增强效应的带状注矩形单栅互作用系统的线性理论，根据动力学方法推导出该系统的“热”色散方程并进行数值计算。在计算过程中考虑了基波回旋共振、二次谐波回旋共振、契伦科夫共振和反常多普勒回旋共振同时存在的叠加效应，将理论计算结果进一步与CST-PS的仿真结果进行比较，两者具有较好的一致性。. 6) 设计并模拟了W波段带状注格栅波导放大器互作用系统，根据理论模型确定大致的结构参数和电参数，设计出具有低反射和高隔离度的带状注矩形单栅和交错双栅放大器，分别对两种结构中只存在契伦科夫共振和多共振效应的情况进行PIC模拟，结果表明，基于共振增强效应的放大器在输出特性上具有显著提升。