Communication through a plasma sheath around a fast moving vehicle

Summary form only given. Investigation of the complicated problem of scattering of electromagnetic waves on turbulent pulsations induced by a sheared flow inside a plasma sheath is important for many applications including communication with hypersonic and reentry vehicles. Theoretical and computational work aimed at improving the understanding of electromagnetic wave scattering processes in such turbulent plasmas is presented. We analyze excitation of low frequency ion-acoustic type oscillations in a compressible plasma flow with flow velocity shear and influence of such turbulent pulsations on scattering of high frequency electromagnetic waves used for communication purposes. The nonlinear system of equations which describes excitation and nonlinear dynamics of low frequency wave turbulence inside a plasma sheath was solved numerically. Results of numerical solutions for plasma density and electric field perturbations for different velocity profiles have been used in the derived expressions for scattered wave energy and scattering cross section. We have appropriately included in our analysis the presence of electron and ion collisions with neutrals as well as electron - ion collisions. An exact expression for the scattering cross section is derived within the framework of single-scattering perturbation theory and the case of incident wave with p-polarization is considered in detail. This approach allows investigation of the scattering process for profiles with different flow velocity shear when representation of excited density and wave field turbulence in analytical form is difficult to obtain.