Mitigation of blackout problem for reentry vehicle in traveling magnetic field with induced current

Abstract

In this paper, a novel solution mitigating the radio blackout problem is proposed, which improves existing traveling magnetic field (TMF)-based methods. The most significant advance lies in replacing the external injection with self-induced current, which does not require electrodes. The improved analytical model is derived to evaluate the electron density reduction taking into consideration the self-induced current for various TMF velocities. The plasma reduction performance is analyzed for several conditions including the total absence of injected current. The results show that the velocity may be used to trade off the injected current and, when sufficiently large, eliminates the need for an injected current while mitigating radio blackout. The effectiveness of this solution to the blackout problem is demonstrated in commonly used aerospace communication bands. With a field strength of less than 0.15 T, increasing the velocity from 40 m s−1 to 3100 m s−1 is all that is required to obviate the need for an injected current. Moreover, typical reduction ratios for electronic density tolerance (2, 1.9, 1.75 and 3 times for the L-, S-, C- and X-bands, respectively, at an altitude of 40 km) remain unchanged. Increasing the velocity of the TMF is much easier than injecting current via a metal electrode into a high-temperature flow field. The TMF method appears practical in regard to possible future applications.