V.S. Sobolev - Dr.Sc. (Eng.), Professor, Chief Research Scientist, Institute of Automation and Electrometry, Siberian Branch of the Russian Academy of Sciences E-mail: sobolev@iae.nsk.su G.А. Kashcheeva - Research Scientist, Institute of Automation and Electrometry, Siberian Branch of the Russian Academy of Sciences F.А. Zhuravel - - Ph.D. (Eng.), Leading Engineer, Institute of Automation and Electrometry, Siberian Branch of the Russian Academy of Sciences

In the paper we investigated the error of the maximum likelihood estimates of the instantaneous frequency (speed) of laser Doppler anemometers signals for streams with periodically varying velocity and turbulent flows. The relevance of these studies is the fact that, unlike the weather radar and lidar, laser anemometers error depends on the measured speed. In this regard the known results of studies the errors of a radar and lidar can\'t be directly applied to assess errors of anemometers. By means of computer simulation the graphics of mean square deviations of estimated frequency from its true values are obtained for typical laser anemometers as a function of number of samples and signal-to-noise ratio. As a result it is shown that the maximum likelihood methodology of obtaining optimal estimates of Doppler frequency for flows with variable velocity can be successfully applied to streams provided that on the time interval occupied by a selected number of samples of the Doppler signal, the frequency remains practically unchanged.

 

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