A particle moving across the interference pattern of two intersecting laser beams scatters the incident light with a temporal variation that enables the calculation of particle velocity. This idea was realized in laser Doppler anemometry (LDA). By recording the light scattering pattern with a fast line scan sensor, the spatial modulation of the signal is also detected. This yields, in addition ...

A so-called six-beam method is proposed to measure atmospheric turbulence using a ground-based wind lidar. This method requires measurement of the radial velocity variances at five equally spaced azimuth angles on the base of a scanning cone and one measurement at the centre of the scanning circle, i.e.using a vertical beam at the same height. The scanning configuration is optimized to minimize...