Hypersonic Vehicle Telemetry Blackout Analysis

Starkey, Ryan P.

doi:10.2514/1.a32051

Cited by 117 publications

(31 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The 'blackout' leads to risks on space missions and air-breathing hypersonic flights in the near space. In order to mitigate the 'blackout' problem, many approaches have been suggested, for example, aerodynamic shaping [4], 'magnetic window' [5], electrophilic ejection [6], high frequency communication and repeater satellite communication [7]. All of those approaches have technical or practical limitations, such as cost, system weight and aerodynamic performance.…”

Section: Introductionmentioning

confidence: 99%

Studies of Terahertz Wave Propagation in Realistic Reentry Plasma Sheath

Chen¹,

Yuan²,

Shen³

et al. 2016

PIER

View full text Add to dashboard Cite

Abstract-Communication 'blackout' is a big challenge for modern space engineering. In the recent decade, the terahertz (THz) technology is believed to be an effective solution for the 'blackout' problem. Many research works about the transmission of THz waves in plasma slabs have been carried out. According to those works, the radio attenuation of THz waves in plasma slabs strongly depends on thickness of the slab, electron density, electron collision frequency and temperature. However, few previous works have paid attention to realistic reentry plasma sheath. In the present paper, a hypersonic fluid model is introduced in order to investigate the structure of the realistic plasma sheath which covers a blunt coned vehicle. The scattering matrix method is employed to study the transmission of THz waves in realistic plasma sheath. According to the present study, the wave frequency, electron density and collision frequency are the most significant factors which determine the attenuation of the THz waves in the plasma sheath. Since the whole plasma sheath is inhomogeneous, to install the antenna at an appropriate position helps mitigate the 'blackout'. For the blunt coned reentry vehicle, installing the antenna on the wall close to the bottom is helpful for mitigating the 'blackout' problem.

show abstract

Section: Introductionmentioning

confidence: 99%

Studies of Terahertz Wave Propagation in Realistic Reentry Plasma Sheath

Chen¹,

Yuan²,

Shen³

et al. 2016

PIER

View full text Add to dashboard Cite

show abstract

“…The plasma flow, which consists of numerous free electrons, ions, and neutral particles, is nonmagnetic, lowtemperature, weakly ionized, and quasi-neutral (i.e., electricity neutral on macroscopic-length scales) [2,3]. It greatly affects the transmission of electromagnetic (EM) waves that it has a very strong interference on the communication between the reentry aircraft and the ground station; it even leads to blackout in certain conditions [4,5]. Moreover, the reflection, refraction, and absorption of EM waves caused by the plasma sheath or wake change the radar scattering characteristics of the hypersonic vehicle [6][7][8][9], which has a significant influence on the detection, tracking, and recognition of the target.…”

Section: Introductionmentioning

confidence: 99%

Backward Scattering Characteristics of a Reentry Vehicle Enveloped by a Hypersonic Flow Field

Sun

Wang

Han

et al. 2018

International Journal of Antennas and Propagation

View full text Add to dashboard Cite

The hypersonic flow field around a reentry vehicle has a significant influence on the ground-vehicle communication as well as on the detection and recognition of the reentry vehicle. Backward scattering characteristics of a reentry vehicle enveloped by a hypersonic flow field are analyzed using a high-order auxiliary differential equation finite difference time-domain (ADE-FDTD) method in this paper. Flow field parameters, including electron density, neutral particle density, and temperature, are obtained by solving the Navier-Stokes (NS) equations numerically. According to the flow field parameters, distributions of the plasma frequency and the collision frequency are then derived. Based on a validity of the physical model and the high-order ADE-FDTD method, backward radar cross sections (RCSs) of a perfect electrical conductor (PEC) sphere enveloped by a hypersonic flow field under different Mach numbers, heights, and incident angles of the electromagnetic (EM) wave are then investigated. Numerical results show that the incident angle of the EM wave exerts noticeable effects on the backward RCS, which is due to an inhomogeneous distribution of the plasma. The flight height and Mach number have significant influences on the distribution of the plasma that they play an important role in the variation of the RCSs. The results presented in this paper provide useful reference data for practical tests in ballistic range or in the high-frequency plasma wind tunnels, where a sphere target is usually used due to its simple shape.

show abstract

“…Since the reentry is a dynamic process, the parameters of a reentry plasma sheath vary simultaneously. Those parameters depend on the aerodynamic shape and flight condition of the vehicle [8,9]. The factors which significantly impact the THz waves' transmission in a realistic plasma sheath are not identical to those in presumed plasma slabs [10].…”

Section: Introductionmentioning

confidence: 99%

Studies on the Effect of Angle of Attack on the Transmission of Terahertz Waves in Reentry Plasma Sheaths

Yuan¹,

Yao²,

Shen³

et al. 2017

PIER M

View full text Add to dashboard Cite

Abstract-The communication 'blackout' in the reentry stage of a space mission is a serious threat to the reentry vehicle. The terahertz (THz) technology is supposed to be a potential solution to the 'blackout' problem in the recent decade. In the present paper, the relation between the THz waves' transmission in the reentry plasma sheath and the angle of attack (AOA) of the vehicle is investigated. A three-dimensional numerical model is introduced in order to obtain the plasma parameters in the reentry plasma sheaths. The computation results show that both the electron density and the electron collision frequency vary with the AOA. As results, the transmission rates for the THz waves vary with the AOA as well. According to the analysis, microwave communication system is very likely to suffer from the 'blackout' in the reentry stage. The THz scheme is an effective solution. The fluctuation of AOA may weaken the signal strength received by the onboard antenna. On the other hand, keeping the AOA in an appropriate range is helpful for strengthening the received THz signals. Also, the AOA for the best THz communication quality is obtained according to the analysis.

show abstract

Hypersonic Vehicle Telemetry Blackout Analysis

Cited by 117 publications

References 9 publications

Studies of Terahertz Wave Propagation in Realistic Reentry Plasma Sheath

Studies of Terahertz Wave Propagation in Realistic Reentry Plasma Sheath

Backward Scattering Characteristics of a Reentry Vehicle Enveloped by a Hypersonic Flow Field

Studies on the Effect of Angle of Attack on the Transmission of Terahertz Waves in Reentry Plasma Sheaths

Contact Info

Product

Resources

About