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This paper present new methodology to address critical refractivity turbulence issues for laser propagation using a new measurement system-a portable balloon-ring platform with multiple fine wire sensors at several separations. All raw data is transmitted to a ground station-allowing spectra to be calculated. The new platform is discussed and preliminary examples of observations, including artifacts, are shown and discussed. This new platform provides capabilities during the daytime as well as nighttime-unlike conventional thermosondes that are used only at night. Such all time observations are important due to the pronounced diurnal variation in the planetary boundary layer where many laser systems are operated. Plans to address the longstanding concern of wake contamination on systems suspended below a balloon quantitatively will be presented. The objective of this effort is to develop the capability that can address several questions related to laser propagation such as: 1) Is the atmospheric isotropic for the scales of interest? 2) Is the turbulence Kolmogorov under various atmospheric conditions, or how often is the structure function represendted by the r2/3 law? 3) what are the profiles of inner and outer scale? 4) To what degree does wake contamination affect conventional thermosonde measurements? 5) Does fine structure within the scattering volume sensed by radar affect refractive index structure parameter (Cn2) and eddy dissipation rate (epsilon) estimates? These questions and concerns will be addressed by making the appropriate observations using the balloon-ring platform. Many of the measurements will be taken at Vandenberg AFB since the Western Test Range operates a ground receiving station, balloon launch facility, VHF radar, boundary layer radars, sodars, and instrumented towers that will enhance this effort. This effort provides an observation platform that will ultimately lead to the development and validation of conceptual/statistical/physical models.© (2002) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only. |
