Remote Atmospheric Wind Speed Measurements by Individual Particle Scattering and Digital Burst Correlation

摘要

We have demonstrated that atmospheric wind speeds can indeed be measured with photon bursts scattered from single dust particles. If photon counting electronics and clipped digital correlation are used for signal analysis, an unambiguous speed measurement can be made with a detected signal as low as ten counts under practical conditions, i.e., in the presence of noise. A microprocessor is used to run the LTV measurements automatically, and to analyze and compare data for both LTV and a conventional cup anemometer. Satisfactory agreement between the LTV and the cup anemometer were obtained. The potential of the LTV with its high speed data acquisition and its short measurement time has been thoroughly demonstrated. In the field test of this automated LTV system, we have conducted speed measurements with both natural aerosols and with seeding of water droplets from a humidifier. To our satisfaction, we obtained better performance without seeding. In short, with the research of this project, we have demonstrated beyond doubt the principle of single-particle scattering for remote speed measurements and also the practical uses of LTV under realistic field conditions. (Author)