Characteristic of high-power microwave propagating through lower ionosphere

Severe attenuation happens when the high-power microwave propagates through a certain altitude. At this altitude, the microwave pulse will ionize the surrounding air and create a plasma, so the severe nonlinear attenuation will be caused, even the breakdown will happen. At the lower ionosphere, the density of the natural ionized free electrons is very intensive. The characteristic of the attenuation when high-power microwave propagates through the lower ionosphere is analyzed in this paper. Calculations indicate that the maximal nonlinear absorption attenuation occurs at the altitude of 50 km. This altitude is very possible to be breakdown. At the same electric-field intensity, the narrower the pulse duration is, the smaller the attenuation coefficient is. At the lower ionosphere, the atte