Modeling Radio Communication Blackout and Blackout Mitigation in Hypersonic Vehicles (original) (raw)
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Modeling of Electromagnetic Manipulation of Plasmas for Communication During Reentry Flight
Journal of Spacecraft and Rockets, 2010
Radio blackout that occurs during hypersonic reentry flight is an important issue for the operation of the vehicle. Since the radio blackout problem is caused by a high plasma number density around a vehicle, it is necessary to manipulate the plasma to allow communication. We suggest a configuration of an ExB layer as a reentry blackout mitigation method. The suggestedExB layer configuration with a two-dimensional magnetic field is simulated using the thermalized potential model and the Poisson-like model in order to illustrate the effectiveness of this approach as a mitigation method. The numerical model uses a magnetohydrodynamics approximation and is solved using a finite volume method with a Riemann solver. The results of the numerical model are assessed using available experimental results.Astrong plasma density reduction is obtained when the high electric and magnetic fields are applied near the cathode. The manipulated plasma region provides a possibility to communicate through a plasma layer during a reentry blackout.
Reentry vehicles: evaluation of plasma effects on RF propagation
2013
In the frame of communication technology relevant to the re-entry vehicles, the communication black-out occurring in the presence of plasma is one of the main challenging issues. The re-entry plasma is a complex physical system, where the ionization derives from a shock-wave and non-equilibrium phenomena. As discussed elsewhere, the time scales of plasma dynamics (including its evolution along mission trajectory) and radio wave propagation are well separated so that radio wave propagation is solved at an appropriate number of time "snapshots" in which plasma dynamics is held unchanged and considered as known. In this activity, a consistent effort has been devoted to model the electromagnetic problem. For the involved range of oprative frequencies and expected densities, the plasma can be considered as an inhomogeneous dielectric. The associated electromagnetic problem is solved in two steps, via use of the field equivalence principle. The vehicle-plasma system is substitut...
PLASMA DENSITY REDUCTION USING ELECTROMAGNETIC E×B FIELD DURING REENTRY FLIGHT
As a vehicle reenters or flies at hypersonic speed through the atmosphere, the surrounding air is shock heated and becomes weakly ionized. The plasma layer thus formed causes a communication problem known as ‘radio blackout’. At sufficiently dense plasma conditions, the plasma layer either reflects or attenuates radio wave communications to and from the vehicle. In this paper, we propose an electromagnetic field configuration as a method to allow communication through the plasma layer. Theoretical models show that this may address the blackout problem under a range of conditions. Preliminary experimental results are also presented.
Plasma Field Telemetry for Hypersonic Flight
2003
Since the beginning of spaceflight, the problems associated with communication blackout caused by the ionized reentry plasma sheath have been studied. Since telemetry blackout originally caused great concern for manned reentry vehicles, ballistic missiles, and atmospheric flight test vehicles, there have been many proposed approaches and associated tests to alleviate the problem.
Open Aerospace …, 2010
An aero-thermo-chemical model is developed to simulate the flowfield, including ionization, around atmospheric re-entry configurations, and its interactions with radio-frequency communication signals (e.g. GPS). The model is successfully validated against literature in-flight measurements of the electron number density, and then applied to the re-entry of recently proposed concepts of slender configurations. The advantages of using sharp and slender geometries for re-entry applications, with respect to radio communication problems, are analyzed and discussed. In addition, an experimental test-bed in an arc-jet plasma wind-tunnel has been setup to reproduce on ground the plasmaradiofrequency interaction. The capability to duplicate on-ground the ionization levels encountered during re-entry has been successfully demonstrated. A numerical model of an Argon plasma jet in chemical and thermal non-equilibrium has also been developed, for numerical rebuilding of the experiments. Both electron number densities and electron temperatures have been successfully correlated, demonstrating the ability of arc-jet facilities, integrated with proper numerical tools, to correctly deal with problems of communication attenuation/black-out.