Simulation of an S-Band MILO with Adjustable Beam Dump

Abstract

This paper details the design, simulation, and optimization of a low-impedance high repetition rate magnetically insulated transmission line oscillator (MILO) driven by a compact Marx generator. The project goals require the MILO to generate an radio frequency (RF) pulse within the S-band frequency range with a peak output power greater than 1 GW with greater than 10% efficiency. Its design is based on a set of base equation which provide critical component dimensions applied to a three-dimensional model constructed within CST studio suite used in a particle-in-cell (PIC) simulation. Additional to the geometric model, simulation of the MILO with non-ideal material properties and a lumped element modeling of the Marx generator were performed. The results of these simulations then informed changes to the model as to the optimizing performance of the device. Within the framework of the model, the final MILO design achieves the design goals with an approximate RF peak power of 4.5 GW at 2.5 GHz operating in the TM 01 mode when an input driving pulse with a peak voltage of 600 kV while providing 58 kA is applied.