Power combination of two phase-locked high power microwave beams from a new coaxial microwave source based on dual beams

The new coaxial high power microwave source based on dual beams has demonstrated two phase-locked output microwave beams generated by its two sub-sources. In order to achieve a single higher output power, we present a three-port waveguide-based power combiner to combine the two microwave beams. Particle-in-cell simulation results show that when the diode voltage is 675 kV and the guiding magnetic field is 0.8 T, a combined microwave with an average power of about 4.0 GW and a frequency of 9.74 GHz is generated; the corresponding power conversion efficiency is 29%. The combination effect of the combiner is further validated in the diode voltage range from 675 kV to 755 kV as well as in the pulse regime. The simulations indicate that the maximum surface axial electric field strength of the electrodynamic structure is 720 kV/cm, which is relatively low corresponding to an output power of 4.0 GW. The stable combined output suggests the probability of long-pulse operation for the combined source.