螺旋分布孔高阶旋转模式激励器的设计

针对Danilov (2007) 提出的高阶模式激励器纯度未知和设计思路模糊的不足, 介绍了一种改进型螺旋分布孔高阶旋转模式激励器, 以实现同轴TE1, 1模式到圆波导TE5, 3模式的高纯度转换。根据不均匀弦方程, 编制了数值计算程序对同轴腔体结构参数进行了优化计算, 使工作模式能够有效谐振。基于小孔衍射理论以及PEC表面的电场边界条件, 详细研究了螺旋分布孔的排列方式和模式抑制器的工作原理。数值计算和仿真结果表明: 在中心频率30GHz附近, TE5, 3模式激励器的模式纯度高达97.4%, 转换效率为96.1%。设计的高阶模式激励器相对于Danilov的结构具有纯度高和紧凑的性能。

Design of high-order rotatingmode generator with helically-distributed perforation

For the shortcomings of unknown mode purity and apparently ambiguous design idea in the literature (Danilov, 2007), an improved rotating high-order mode generator based on the helically-distributed perforation (HDP) technique is presented to realize high purity conversion of coaxial TE1, 1 mode to circular TE5, 3 mode.According to the inhomogeneous string equation, the optimal configurations of the coaxial cavity are obtained by the numerical calculation so that the required mode can effectively resonate.Based on the pinhole diffraction theory and the electric field boundary conditions on the surface of the perfect electric conductor (PEC), the arrangement of HDP and the working principle of the mode suppressor are studied in detail.Numerical calculations and simulation results indicate that the mode purity of TE5, 3 mode generator is as high as 97.4%, and the conversion efficiency is 96.1% near the center frequency of 30 GHz.Compared with its old version, the generator has the obvious advantages of high mode purity and compactness.