详细研究了Denisov型准光模式变换器的原理和设计方法。应用几何光学理论对Denisov型开口辐射器的工作过程进行了分析, 并给出了基于耦合模理论的辐射器不规则扰动段的设计方法。开发了基于耦合模理论、矢量衍射积分和物理光学法的仿真程序GQOMC-D, 并将该程序的计算结果与文献报道结果进行了对比验证。利用该程序设计了一种110 GHz TE22, 6模回旋振荡管准光模式变换器, 仿真结果显示在输出窗上得到了场型较好的高斯波束, 其模式纯度为98.4%, 模式变换器的能量转换效率为94.7%。

The principle and design method of Denisov-type quasi-optical mode converter is investigated in detail. The operation process of the Denisov-type launcher is analyzed by applying the geometrical optics, and the Gaussian-like field distribution achieved on the waveguide wall is also derived. The method for designing a rippled-wall launcher is proposed on the basis of coupled mode theory. A simulation code for Denisov-type quasi-optical mode converter GQOMC-D is developed based on coupled mode theory, vector diffraction integration and physical optics, which is compared to the design parameters and experimental results reported in literature for its validity. According to this code, a Denisov-type quasi-optical mode converter used in 110 GHz TE22, 6 mode gyrotron oscillators is designed. Simulation results indicate that a Gaussian-like beam is obtained at the output window with a scalar content of 98.4% and a conversion efficiency of 94.7%.