Ｅffect on air refraction index by effective electric-field intensity in high power microwave propagation

The intense field of high power microwave causes ionization of neutral particle in atmosphere and the plasma comes into being. The ionization frequency of neutral particle relates to electric field intensity and atmospheric pressure. This paper presents the interaction between electron and air neutral molecules in comparatively wide region. When an impulse of high power microwave is propagated, the variation of electron concentration and refractive index accompanying with that of effective electric-field also intensity is also introduced．