利用波导截止特性测量微波源辐射功率

 对波导的截止特性作了理论分析，并分析了利用该特性进行高功率微波功率测量的可行性及准确性。在远场条件下，利用该特性对工作频率为1.75 GHz的磁绝缘线振荡器进行了微波功率测量。测量结果表明：微波源辐射功率2.3 GW，辐射模式为TM01主模，实测辐射模式方向图与模拟计算结果一致，微波脉宽大于40 ns，未发现明显的功率击穿现象；使用波导截止特性测量微波功率是可行的，有利于防止接收喇叭的功率击穿，测量精度较高。

Measurment of output power of microwave sources using cutoff characteristic of waveguide

The cutoff characteristic of waveguide is theoretically analysed in this paper,as well as the feasibility and accuracy in measuring the output power of HPM using the characteristic.It was used to measure the output microwave power of a magnetically insulated transmission line oscillator(MILO) operating at 1.75 GHz in far-field region.The experimental results show that a 2.3 GW high power microwave of TM01 mode is detected from the MILO device.The detected radiation pattern agrees with that of the simulation well.The microwave pulse width is more than 40 ns,and there is no obvious microwave power breakdown.It is good to use the cutoff characteristic of waveguide to prevent the power breakdown of the receiving horn and improve the measuring accuracy.