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Interaction of electromagnetic and acoustic waves in a stochastic atmosphereIn the Stanford radio acoustic sounding system (RASS) an electromagnetic signal is made to scatter from a moving acoustic pulse train. Under a Bragg-scatter condition maximum electromagnetic scattering occurs. The scattered radio signal contains temperature and wind information as a function of the acoustic-pulse position. In this investigation RASS performance is assessed in an atmosphere characterized by the presence of turbulence and mean atmospheric parameters. The only assumption made is that the electromagnetic wave is not affected by stochastic perturbations in the atmosphere. It is concluded that the received radio signal depends strongly on the intensity of turbulence for altitudes of the acoustic pulse greater than the coherence length of propagation. The effect of mean vertical wind and mean temperature on the strength of the received signal is also demonstrated to be insignificant. Mean horizontal winds, however, shift the focus of the reflected electromagnetic energy from its origin, resulting in a decrease in received signal level when a monostatic radio-frequency (RF) system is used. For a bistatic radar configuration with space diversified receiving antennas, the shifting of the acoustic pulse makes possible the remote measurement of the horizontal wind component.
Document ID
19790053077
Document Type
Reprint (Version printed in journal)
Authors
Bhatnagar, N. (Science Applications, Inc. Palo Alto, Calif., United States)
Peterson, A. M. (Stanford University Stanford, Calif., United States)
Date Acquired
August 9, 2013
Publication Date
May 1, 1979
Publication Information
Publication: IEEE Transactions on Antennas and Propagation
Volume: AP-27
Subject Category
COMMUNICATIONS AND RADAR
Funding Number(s)
CONTRACT_GRANT: N00014-C-0601
CONTRACT_GRANT: NGL-05-020-014
Distribution Limits
Public
Copyright
Other