Electromagnetic Properties of High-Temperature Air

This paper concerns the attenuation and phase characteristics of plasmas and, in particular, the electromagnetic properties of high-temperature air. It is shown that by a suitable normalization of the parameters the electromagnetic properties of plasmas may be universally represented in convenient form in either the complex dielectric coefficient plane or the complex propagation constant plane. Next, the electron number densities and electron collision frequencies for air ranging in temperature from 3000° to 12,000°K and in density from 101 to 10-4 times the density at sea level are illustrated. The attenuation and phase constants for an electromagnetic wave traversing this medium have been evaluated for frequencies from 109 to 1011 cps. As an example, the above universal representation is applied to the stagnation region of a hypersonic vehicle in space.