Crosswind from a Single Aperture Scintillometer using Spectral Techniques

In this study, spectral techniques to obtain the crosswind from a single large aperture scintillometer (SLAS) time series are investigated. The crosswind is defined as the wind component perpendicular to a path. A scintillometer obtains a path-averaged estimate of the crosswind. For certain applications this can be advantageous, e.g. monitoring the crosswind along airport runways. The essence of the spectral techniques lies in the fact that the scintillation power spectrum shifts linearly along the frequency domain as a function of the crosswind. Three different algorithms are used, which we named the Corner Frequency (CF), Maximum Frequency (MF), and the Cumulative Spectrum (CS) technique. The algorithms track the frequency shift of a characteristic point in different representations of the scintillation power spectrum. The spectrally derived crosswinds compare well with sonic anemometer estimates. The CS algorithm obtained the best results for the crosswind when compared with the sonic anemometer. However, the MF algorithm was most robust in obtaining the crosswind. Over short time intervals (