Influence of the plasma sheath on the radiation characteristics of an antenna

An aircraft reenters or flies at hypersonic speed through the atmosphere is surrounded by plasma sheath that affects on the radiation characteristics of an antenna. According to actual problems, the Navier-Stokes equations is solved using the more effective and stable AUSMPW+ scheme. The calculated electron density distribution in the sheath is concerned with the flow structure which is shown to be quite sensitive to the vehicle speed. Based on this computation module, the dependence of the attenuation coefficients on frequency is obtained by the modified WKB method. For the radiation characteristics investigation, a slot antenna covered by a plasma sheath is presented in this paper. The results showed that such a plasma sheath affects chiefly on the meridian radiation patterns, and less on the equatorial ones. Conclusions obtained are helpful for combined design of antenna on the hypersonic aircraft.