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Wind profiles in the atmospheric boundarylayer are a very important parameter also to study atmospheric exchange processes. Alaser Doppler anemometer was designed, constructed and testet. The system consists of the laser Doppler anemometer mounted on a pedestal and controlled by a personal computer. A sine wave fitting computer program is used to get the wind velocities and wind direction for the levels selected. This sophisticated program can distinguish between cloud and aerosol signals and uses also the azimuthal anglevelocity for extracting the direction of the wind. The wind field in the atmospheric baundarylayer is highly variable in spatial and temporal scales. For a few possible applications a more frequent wind sensing is necessary, i.e. - forairports located in low level jet areas, -forchemical plants to get information of the transport of toxic gases from leakages, -for military application (artillery). Only a few techniques can be applied to get the wind field in the boundarylayer. The laser Doppler systems are a candidate. There are a few laser anemometry projects performed during the past years (Woodfield and Vaughan,1983, KOpp et al.,1984). RSRE designed and manufactured with GECa LAser True Airspeed Sensor (LATAS) ,a very compact system in the early 80's. Also RSRE and GEC designed and manufactured a cw-laser Doppler system for DLR in 1981. This system was installed in a container and has been operated at airports, artillery ranges and m a Northsea research platform (Werner et al.,1986). Pulsed systems with larger range capacity are in use at NOAA-Boulder (M.J.Post,1990). This paper summarizes the principle technique, gives the special design of the new compact system and presents test and simulation results. The requirements for the system are a compact design and an automatic or half-automatic operation
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