An electromagnetic method for removing the communication blackout with a space vehicle upon re-entry into the atmosphere

Abstract

When a hypersonic vehicle travels in the Earth and Mars atmosphere, the surface of the vehicle is surrounded by a plasma layer, which is an envelope of ionized air, created from the compression and heat of the atmosphere by the shock wave. The vehicles will lose contact with ground stations known as the reentry communication blackout. Based on the magnetohydrodynamic framework and electromagnetic wave propagation theory, an analytical model is proposed to describe the effect of the effectiveness of electromagnetic mitigation scheme on removing the reentry communication blackout. C and Global Positioning System (GPS) bands, two commonly used radio bands for communication, are taken as the cases to discuss the effectiveness of the electromagnetic field mitigation scheme. The results show that the electron density near the antenna of vehicles can be reduced by the electromagnetic field, and the required external magnetic field strength is far below the one in the magnetic window method. The directions of the external electric field and magnetic field have a significant impact on the effectiveness of the mitigation scheme. Furthermore, the effect of electron collisions on the required applied electromagnetic field is discussed, and the result indicates that electron collisions are a key factor to analyze the electromagnetic mitigation scheme. Finally, the feasible regions of the applied electromagnetic field for eliminating blackout are given. These investigations could have a significant benefit on the design and optimization of electromagnetic mitigation scheme for the blackout problem.

Resonant interaction of electromagnetic wave with plasma layer and overcoming the radiocommunication blackout problem

“…by injecting water drops) is also quite a difficult task. It is also possible to reduce the plasma density near the vehicle by applying additional external electric or magnetic fields which is proposed in [22,23]. However, the strength of the fields to be applied is large and realization of the idea is rather complicated.…”

Effects of pulsed magnetic field on density reduction of high flow velocity plasma sheath

“…to ´-12 10 m , 16 3 and the thickness of plasma layer is set to 0.1 m. The signal attenuation coefficient decreases with the decrease of electron density. When the signal attenuation exceeds 30 dB, the communication blackout problem will appear [24]. Therefore, when the initial plasma number density is ´-1 10 m , 3 which means that the reduction of electron density should be more than 26%.…”

Experimental study of radio frequency waves resonant transmission through a semiconductor plasma sheet with supercritical electron density

“…The radio communication blackout could cause the long-time interruption of the signal transmission between the vehicle and the ground stations, lasting up to several minutes, so a number of methods have been proposed to mitigate it. Among them are the creation of transparency windows using electric and magnetic fields [12][13][14][15][16], the conversion of radio waves into so-called whistling waves that can penetrate through the dense layers of plasma [17], the injection electronegative liquids (water vapour) or metal-oxide ceramic particles [18] into the plasma region in order to reduce the plasma density and so on. However, all these methods have strong limitations when using in practice since they require significant modifications of the aircraft design, namely, an additional installation of high-power electromagnetic energy sources or containers with large volumes of sprayed substances.…”