A 324 MHz 200 kW waveguide-to-coaxial adaptor has been designed and fabricated for a microwave coupler in a radio frequency quadrupole system. Optimization of the adaptor is performed by the numerical study and experimental test. High-power measurements show that the reflection coefficient of the adaptor is less than −30 dB at the RFQ operating frequency, and there is no breakdown in the 228 kW pulse test. The measurement results are consistent with the simulation results, indicating that the adaptor has good high-power transmission performance. This work provides theoretical and experimental bases for a rectangular-to-coaxial adaptor design, especially in high-power steady-state operation.

中文翻译：

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用于射频四极微波系统的324 MHz 200 kW CW波导同轴适配器的设计

已经设计和制造了一个324 MHz 200 kW波导同轴适配器，用于射频四极杆系统中的微波耦合器。通过数值研究和实验测试对适配器进行优化。高功率测量表明，适配器在RFQ工作频率下的反射系数小于-30 dB，并且在228 kW脉冲测试中没有击穿。测量结果与仿真结果一致，表明该适配器具有良好的大功率传输性能。这项工作为矩形到同轴适配器的设计提供了理论和实验基础，尤其是在大功率稳态操作中。