Accession Number : ADA018062

Title :   The use of an Acoustic Echo Sounder for Optical Tracking Applications.

Descriptive Note : Instrumentation papers,

Corporate Author : AIR FORCE CAMBRIDGE RESEARCH LABS HANSCOM AFB MASS

Personal Author(s) : Haugen,Duane A. ; Kaimal ,J. Chandran ; Newman,Jim T.

Report Date : 21 AUG 1975

Pagination or Media Count : 60

Abstract : A pilot study to obtain data on the seeing quality of the atmosphere was conducted in August 1974 as part of ARPA's Compensated Imaging Program at the ARPA Maui Observation Station (AMOS). The AMOS site is located atop Mt. Haleakala, about 10,000 ft above sea level, on the island of Maui, Hawaii, presumably in an environment where degradation of optical tracking due to turbulent fluctuations in the index of refraction is minimal. As the compensated Imaging Program evolved, it became increasingly clear that detailed knowledge of atmospheric turbulence properties at AMOS was essential to the success of the program. One aspect of the pilot study conducted was to evaluate the feasibility of using an acoustic echo sounder to obtain that information. The results of that evaluation are summarized in this report. In general, subject to certain limitations, it was found that the acoustic echo sounder shows valuable potential as a remote probe for quantitative determination of the temperature structure parameter to heights in excess of 300 m. Since the temperature structure parameter is directly related to the refractive index structure parameter, the sounder is immensely useful for general application to optical propagation programs.

Descriptors :   *Atmospheric sounding, *Echo ranging, *Acoustics, Remote systems, Probes, Backscattering, Turbulence, Atmospheric motion, Optical tracking, Light transmission, Interference, Refractive index

Subject Categories : Atmospheric Physics
      Optical Detection and Detectors
      Acoustics
      Radiofrequency Wave Propagation

Distribution Statement : APPROVED FOR PUBLIC RELEASE