Electro-acoustic scattering in an atmosphere with wind

Abstract

An electromagnetic wave propagating in the atmosphere is scattered by a beam of acoustic waves. The paper studies how a wind interferes with the scattering process. The purpose is to use the results for measuring the wind velocity and the temperature of the atmosphere at varying heights. A scattering calculation is carried out by means of standard methods used in problems of wave scattering. The scattering characteristics show a pronounced resonance, due to interference between spherical, i.e, nonplanar, waves. The resonance, and particularly the width of the resonance curve, represents a possibility of measuring the temperature of the atmosphere in the scattering region. The paper points out the advantage of having the acoustic beam generated by an array of phase controlled elementary acoustic sources. This opens the possibility of counteracting the effect of the wind on the acoustic beam so that the beam is keeping its direction undisturbed by the wind. By this method the problem of measuring the horizontal wind components is converted to a measurement of phase.

Electro-Acoustic Scattering From a Pulsating Sphere

“…Acoustic pressure variations have a direct impact on the dielectric inhomogeneities in the surrounding medium. This phenomenon is used to observe wind speed and direction using a method proposed in [12,13].…”