为实现基于相对论返波管振荡器的高功率微波相干合成, 开展了针对锁相的低磁场返波管优化设计。通过优化中间调制腔的位置, 降低工作模式的 Q值, 达到降低种子微波功率的目的。以外注入微波锁相方式为例, 优化后的器件锁定增益大于 20 dB, 20 MW的注入微波功率即可实现对 GW级的微波输出的相位控制。研究结果对调制电子束锁相也具有参考价值。

For the purpose of coherent high power microwave combining based on Relativistic Backward Wave Oscillator(RBWO), an optimal design of a low magnetic field RBWO is present. In order to decrease the requirement on the seed RF power for phase locking, the axial position of the intermediate bunch cavity of the RBWO is optimized to decrease the Q-value of the working mode. Particle In Cell(PIC) simulation shows that an input power of 20 MW is sufficient to lock the frequency and phase of the output. And the corresponding gain is higher than 20 dB. The result is also valuable for phase locking by modulated electron beams.