Spatial Selectivity of Plasma Sheath Channel at Millimeter Wave Band for Hypersonic Vehicle

Millimeter wave is a potential way to overcome the blackout problem. However, the plasma sheath is axially nonuniform, and it has different effects on millimeter wave at different axial positions. In this article, the influences of the spatially inhomogeneous time-varying plasma sheath on millimeter waves are investigated. The electron density model is established, the time-domain sequence of the random channel is calculated, and the channel statistical parameters at different axial positions are extracted. The results show that the millimeter wave channel is spatially selective. Millimeter waves can transmit through the plasma sheath with less attenuation, multiplicative interference, and nonlinear effects at any position of the vehicle except the nose. When the antenna position is properly selected, the attenuation and multiplicative interference intensity can be further reduced. This indicates that millimeter wave communication technology is the most promising way to overcome the blackout problem and accomplish diverse communication tasks of a hypersonic vehicle.