给出了Ka 波段相对论绕射辐射振荡器(RDG)的辐射功率测量方法和实验结果。器件采用带反射器两段式过模慢波结构，由于器件的过模结构特点，实验选择用空间积分方法测试辐射功率。在准确标定测量系统的基础上进行了热测实验，得到了辐射模式图和辐射总功率。测试结果表明：微波辐射功率超过300 MW，信号脉宽大于10 ns，辐射频率介于34～38 GHz之间，辐射模式为TM0n模。关 键 词 绕射辐射振荡器; 辐射场测量; 辐射模式; 方向图Abstract This paper presents the method and results of measurement of radiation power for Ka-band relativistic diffraction generator. The RDG device has two section slow wave structure. For the character of complete overmoded SWS, the spatial integral method of the radiation power measurement is carried out. The radiation mode image and total power are obtained by hot test, which is based on precisely calibrating of the measurement system. The measurement results show that the radiation power exceeds 300 MW with a frequency of 34~38 GHz and a pulse width exceeds 10 ns, and the radition mode is TM0n mode.Key words relativistic diffraction generator; radiation field measurement; radiation mode; radiation pattern