Nonlinear Theory for a Compact Radial Extended Interaction Oscillator

In this paper, a nonlinear theoretical simulation method based on a 1-D electron ring model for a new extended interaction structure-the radial extended interaction oscillator (R-EIO)-working in the fundamental mode is presented. The R-EIO has a compact structure and good heat dissipation characteristics. Furthermore, because of a significant increase in the electron injection channel area, the R-EIO has the potential for higher power operation using the same current density condition as a traditional EIO structure, giving it great research value. This paper presents an example of predicted R-EIO performance based on the results of nonlinear theoretical simulation and particle-in-cell (PIC) code simulation. At a voltage and current of 3 kV and 8.48 A, respectively, the theoretical simulations predict that the as designed R-EIO could generate 1.8 kW at 12.2104 GHz, while the PIC simulation predict 1.7 kW at 12.5 GHz. Similar results could be obtained from the nonlinear theoretical simulation, which cost less than 5 min, while about 50 h for PIC code simulation in the same computer condition.