Study of a W Band Extended Interaction Oscillator Using Interlaced Staggered Resonant Cavities

An extended interlaced staggered resonant cavity is proposed, based on the staggered dual vane slow wave structure. For the given voltage 19 kV to 20 kV at the frequency of 94.37 GHz, the effective impedance (M2R/Q) of the proposed EISRC were calculated by using MATLAB software, the 23/12 π-mode has the highest effective impedance, the strongest modulation effect to the electronic beam. The input and output of the signal is through a coupling hole connecting to external BJ1400 standard rectangular waveguide. The structure of the coupling hole is properly designed to achieve the external quality factor Qe of 792.87. By using the Time Domain Solver, the S11 is −16.56 dB and the group delay τ is 29.65 ns while the background material is set to oxygen-free copper (σ = 2.8 × 10^7 S∕m). Then the hot performance of the EIO has been investigated by using particle in cell (PIC) simulation, where the area of the electron channel is 1.2 mm × 0.3 mm, the current is 0.6 A, and the uniformly focused magnetic field is 0.5 T. When a sinusoidal RF signal of 5 mW is fed into the input port, the output power is stabilized at 655.22 W, corresponding a gain of 61.87 dB.