Multipactor Mitigation Via Gaussian-Shape Transverse rf Electric Field Near a Dielectric Surface

Abstract

High power microwaves are widely used in space-based communication systems, where multipactor discharges near the microwave window have been a limiting factor [1] . The mitigation of multipactor is of importance for avoiding ionization breakdown and improving signal transmission [1] - [3] . In this work, an engineered Gaussian waveform transverse electric field is demonstrated to be capable of reducing the multipactor strength by an order of magnitude for a fixed input power density 1.2X10 10 W/m 2 [3] , and the corresponding susceptibility of multipactor versus the rf electric field amplitude is also investigated via kinetic particle-in-cell simulations and multi-particle Monte Carlo simulations [4] , [5] . The results show that, at a larger half peak width of the Gaussian waveform Δτ = 0.15T with T = 1ns the rf period, the susceptibility of multipactor is similar to that of a single frequency sinusoidal waveform-driven multipactor. However, at a decreased half peak width Δτ = 0.07T, the multipactor strength decreases with increasing rf electric field amplitude, the unit growth rate is a closed curve in the plane of rf electric field amplitude and dc restoring electric field, implying the effectiveness of Gaussian waveforms in mitigating multipactor in real applications.