Comparison of Various Microwave Breakdown Prediction Models

Abstract

This paper is concerned with presenting a comparison of various microwave breakdown prediction models when applied to predicting breakdown of a practical antenna system located in a partially ionized environment. Solutions for the breakdown conditions are obtained numerically, allowing for the field and environment properties to have arbitrary spatial variation. The models are applied to predictions of breakdown for an S-band slot radiating from a reentry vehicle, and the enviroment properties are taken from aerodynamic conditions existing along the descent trajectory. The three models compared consist of a linear model, a variational model, and a nonlinear model. The models are based on the electron-continuity equation and allow for the effects of diffusion (including the transition from ambipolar to free diffusion), high-temperature effects, and recombination, which, to our knowledge, have not been treated previously in a single model.