Abstract

In the majority of cases by using a laser Doppler system for remote velocity measurements, the direction of the movement is known and the method therefore only needs the information on the magnitude of the velocity. For ground based wind measurements, the conditions are far more unfavourable: the targets are aerosol particles of different size distribution, the direction of movement is indefinite (except for rain and falling snow, where the Z-component is known), and the backscatter power is small. As long as the reference signal for the mixing is derived from the transmitter (homodyne system), the ambiguity of the sign cannot be eliminated.

© 1987 Optical Society of America