Atmospheric Turbulence Effects on the Temporal Spectral Densities of Optical Signals.

Abstract

This summary report describes the major efforts and results obtained during the contract period. The objectives were to extend the applicability of optical methods of crosswind sensing to obtain operation under strong turbulence conditions, and to investigate the effects of motion on the optical speed measurement. Two optical windspeed instruments designed to be unaffected by strong turbulence were built and tested. One design was based on the measurement on the time delay required to obtain a peak in the crosscorrelation function derived from intensity fluctuations, and the second design was based on fluctuations of the beam angle of arrival. Both instruments were tested over 2 km paths and the operation was unaffected by increasing turbulent strength. An instrument, using an optical beam and spatial filters at the transmitter and receiver, was built to demonstrate the feasibility of the technique to profile corsspath windspeeds along the beam. The device was tested to path lengths of 500 m and operated satisfactorily. A study was conducted on the errors produced in an optical wind speed measurement due to motion of the receiver and/or beam source. (Author)

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Document Details

Document Type
Technical Report
Publication Date
Jul 31, 1979
Accession Number
ADA073231

Entities

People

  • Jack Smith

Organizations

  • University of Texas at El Paso

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Anemometers
  • Angle Of Arrival
  • Atmospheric Motion
  • Atmospheric Sciences
  • Cross Correlation
  • Crosswinds
  • Electrical Engineering
  • Engineering
  • Filters
  • Filtration
  • Intensity
  • Measurement
  • Optical Instruments
  • Radiation Measuring Instruments
  • Saturation
  • Turbulence
  • Wind

Fields of Study

  • Physics

Readers

  • Fluid Dynamics.
  • Pulsed Power and Plasma Physics.
  • Radar Systems Engineering.