In this paper,the finite-difference time-domain(FDTD)algorithm is employed to simulate microwave pulse coupling into the dielectric slot on a rectangular cavity.We investigate the factors that influence the coupling resonant peak and resonant frequency of the dielectric slot,including the slot length,slot width,and relative dielectric constant. Numerical results show that the equation of resonant frequency for microwave coupling into the dielectric slot is modified. Finally,the resonant condition of rectangular cavity with a dielectric slot is provided.
The dispersion relation of a conventional 6-vane relativistic magnetron is derived and numerically calculated, which is employed to analyze the operating frequency of the device.Initial results of three-dimensional particle-in-cell simulation show that an average output microwave power of about 0.96GW at 4.5GHz is obtained at the beam energy of 437keV and current of 12.2kA when the externally applied magnetic field is about 0.6T.The efficiency is about 18%. An average output power of microwave about 4.4GW at 4.37GHz is also obtained at the beam energy of 1.05MeV and the current of 20.TkA when the structure parameters are improved.The efficiency is about 20%.
