Simultaneous Dual-Frequency High-Power Microwave Generation in a Relativistic Transit-Time Oscillator for X-Band and Ka-Band: Preliminary Experimental Study

This letter presents the experimental validation of a dual-frequency high-power microwave (HPM) source utilizing a relativistic transit-time oscillator (RTTO), which achieves simultaneous output in the X-band and Ka-band. To enhance measurement precision and signal isolation between the dual-frequency HPM outputs, a band-pass filter was introduced into the Ka-band measurement system. The device exhibits a compact nested structure and operates stably at a voltage of 440 kV with a low guiding magnetic field of 0.6 T, while generating output powers of 1.1 GW in the X-band and 0.25 GW in the Ka-band, with pulse widths of 80 ns and 28 ns, respectively. The generated microwave modes have been confirmed as symmetric TM<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_{\text {0{n}}}$ </tex-math></inline-formula> by conducting mode analysis, validating stable operation of the device. The experimental results substantiate that the device efficiently generates dual-frequency HPMs under low magnetic field conditions, presenting distinct advantages in compactness and lightweight dual-frequency HPM source design. Future work will focus on improving the device’s stability and output efficiency, thereby enhancing its practicality and reliability.