Optimized Magnetic Field Design for Mitigating RF Communication Blackout

Endo-atmospheric flight at hypersonic speeds creates an extraordinarily harsh aerothermal environment where an ionized plasma layer may surround some parts of the vehicle. Free electrons in the plasma, due to their relatively small mass, are able to rapidly reflect and/or absorb some radio-frequency (RF) signals. The frequency threshold at which transmission is reduced is usually referred to as the cutoff frequency. Broadly speaking, for RF signals below the cutoff frequency, RF signal transmission is significantly reduced. This reduction effect is often referred to as ōcommunication blackoutö in scientific literature and has been experienced by reentry vehicles dating back to NASAÆs early Apollo programs. As the Department of Defense (DoD) pushes offensive and defensive capabilities further into hypersonic regimes, RF communication blackout is an emerging problem which must be mitigated. Over the years, a variety of solutions have been proposed to mitigate hypersonic blackout. Thus far, the most promising is the generation of large magnetic fields which reduce the electron density in the vicitinty of radomes. This proposed effort will leverage the existing VLOX MultiPhysics (VMP) commercial solver to design an optimized magnetic field geometry and an IERUS ongoing investment in thermally adaptive antennas to provide a turn-key solution for mitigating RF communication blackout during hypersonic flight.