For the shortcomings of large size and narrow band width, a variable-period serpentine circular waveguide mode converter is proposed to realize high efficiency conversion of TE01 to TE11. According to the coupled wave equation, the optimal configurations of a variable-period converter and a traditional one (their radii are all 16 mm) are respectively obtained to realize the optimal mode conversion at 30. 5 GHz. Calculation results show that the variable-period converter with a optimal length of 1 056. 97 mm, realizes a TE11 conversion efficiency of 98. 1% with its TE11 conversion bandwidth over 90% being 3. 3%. However, the traditional converter with a optimal length of 769. 53 mm, realizes a TE11 conversion efficiency of 99. 3% with its TE11 conversion bandwidth over 90% being 5. 9%. The variable-period converter assumes evident advantages in size and bandwidth over the traditional one. Test results indicate that the variable-period converter acts very well in conversion of TE01 to TE11 mode.%针对蛇形圆波导变换器尺寸大和带宽窄的不足,提出了变周期蛇形圆波导模式变换器,以实现TE01到TE11模式的高效率转换.根据耦合波方程,编制了优化计算程序,对工作于30.5 GHz、半径为16 mm的变周期以及传统蛇形变换器几何结构分别进行了优化计算,得到了可实现最高模式变换效率的几何参量.计算结果表明:传统结构变换器最优长度长达1056.97 mm,转换效率98.1％,90％以上转换带宽也仅为3.3％;变周期变换器最优长度为769.53mm,转换效率为99.3％,90％以上转换带宽为5.9％.变周期结构相对于传统结构的模式变换器具有尺寸小和带宽宽的明显优势.测试表明所提出的模式变换器具有良好的模式变换性能.
展开▼
