设计了一种高功率圆波导TM01-矩形波导TE10模式转换器，可以实现圆波导TM01模式与矩形波导TE10模式之间的相互转换。仿真结果表明：中心频率为9.7 GHz时该模式转换器转换效率大于99.99%，回波损耗小于-40 dB,转换效率大于90%时的带宽大于0.4 GHz。调节底面短路圆波导长度可以实现模式转换器在9.2~10.1 GHz范围内调谐(模式转换效率大于99%)。在圆波导和耦合段连接处引入倒角可有效降低场强，提高功率容量，注入功率0.7 GW，其表面场强小于1 MV/cm。

A compact high power microwave circular waveguide TM01-rectangular waveguide TE10 mode converter was designed to realize the high efficiency mode conversion and high power capacity. The simulation result shows that the mode conversion efficiency with a center frequency of 9.7 GHz is more than 99.99%, the return loss is smaller than -40 dB， and the bandwidth with conversion more than 90% exceeds 0.4 GHz. The frequency of the mode converter is tunable for 9.2-10.1 GHz (the efficiency of the mode conversion exceeds 99%) by changing the length of the short circular waveguide. The chamfer angle between the input circular waveguide and coupling circular waveguide can depress the field enhancement and improve the power capacity. The max surface E-field is 100 MV/m with an incident power of 0.7 GW.