AMT Atmospheric Measurement Techniques AMT Atmos. Meas. Tech. 1867-8548 Copernicus Publications Göttingen, Germany 10.5194/amt-6-1673-2013 Retrieving wind statistics from average spectrum of continuous-wave lidar Branlard E. 1 Pedersen A. T. https://orcid.org/0000-0002-9132-1357 1 Mann J. https://orcid.org/0000-0002-6096-611X 1 Angelou N. https://orcid.org/0000-0002-9627-422X 1 Fischer A. 1 Mikkelsen T. 1 Harris M. 2 Slinger C. 2 Montes B. F. 3 DTU Wind Energy, Risø Campus, Technical University of Denmark, Roskilde, Denmark ZephIR Ltd., The Old Barns, Fairoaks Farm, Hollybush, Ledbury, HR8 1EU, UK LM Wind Power, Lunderskov, Denmark 15 07 2013 6 7 1673 1683 Copyright: © 2013 E. Branlard et al. 2013 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://amt.copernicus.org/articles/6/1673/2013/amt-6-1673-2013.html The full text article is available as a PDF file from https://amt.copernicus.org/articles/6/1673/2013/amt-6-1673-2013.pdf

The aim of this study is to experimentally demonstrate that the time-average Doppler spectrum of a continuous-wave (cw) lidar is proportional to the probability density function of the line-of-sight velocities. This would open the possibility of using cw lidars for the determination of the second-order atmospheric turbulence statistics. An atmospheric field campaign and a wind tunnel experiment are carried out to show that the use of an average Doppler spectrum instead of a time series of velocities determined from individual Doppler spectra significantly reduces the differences with the standard deviation measured using ordinary anemometers, such as ultra-sonic anemometers or hotwires. The proposed method essentially removes the spatial averaging effect intrinsic to the cw lidar systems.

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