Low Frequency Plasma Turbulence as a Source of Clutter in Surveillance and Communication
نویسنده
چکیده
Presence of plasma turbulence can strongly influence propagation properties of electromagnetic signals used for surveillance and communication. In particular, we are interested in the generation of low frequency plasma turbulence in the form of coherent vortex structures coexisting with short scale density irregularities and of lower hybrid turbulence. Lower-hybrid type density irregularities are excited by plasma flows with velocity shear, whereas interchange or flute type oscillations in magnetized plasma are associated with Rayleigh-Taylor type instability. These types of density irregularities play important role in refraction and scattering of high frequency electromagnetic signals propagating in the earth ionosphere, inside a plasma sheath of reentry and hypersonic vehicles and in many other applications. We will discuss generation of low frequency density irregularities due to the presence of plasma flows with velocity shear and interchange instability.
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