Communication through plasma sheaths via Raman (three‐wave) scattering process

A mechanism of communication through plasma sheaths which surround vehicles traveling at hypersonic velocities is proposed. The idea is to place a source of an intensive, high frequency electromagnetic pump wave on the vehicle and to use the nonlinearity of the medium to create a backscattered Stokes wave through the interaction of the pump wave with the signal‐carrying wave sent by a ground transmitter. Such an interaction will be mediated by the plasma oscillations generated in the process of the resonant absorption of the signal‐carrying wave. The advantages of this mechanism for information transfer are that the high frequency pump wave only is present in a small region near the vehicle and that the signal wave can have relatively low frequency.