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The FATMOSE trial (FAlse-bay ATMOSpheric Experiment) running over a period from November 2009 to July 2010,
was a continuation of the cooperation between TNO and IMT on atmospheric propagation and point target detection and
identification in a maritime environment. Instruments were installed for measuring scintillation, blurring- and refraction
effects over a 15.7 km path over sea. Simultaneously, a set of instruments was installed on a mid-path lighthouse for
collecting local meteorological data, including scintillation, sea surface temperature and visibility. The measurements
covered summer and winter conditions with a prevailing high wind speed from the South East, bringing in maritime air
masses. The weather conditions included variations in the Air-Sea Temperature Difference (ASTD), that may affect the
vertical temperature gradient in the atmospheric boundary layer, causing refraction effects in the lightpath. This was
measured with a theodolite camera, providing absolute Angles of Arrival (AOA). Blur data were collected with a high
resolution camera system with 10 bits dynamic range. Specially designed image analysis software allows determination
of the atmospheric blur, while simultaneously providing information on the Scintillation Index (S.I.). This S.I. was also
measured by using the Multiband Spectral Radiometer Transmissometer (MSRT). The ratio of the transmission levels of
this instrument contains information on the size distribution of the aerosols along the path. In the paper, experimental
details on the set-up and the instrumentation are given as well as the methods of analysis. Preliminary results are shown,
including a comparison of measured blur and scintillation data with Cn
2 data from the scintillometer, correlation between
AOA and ASTD and comparison of transmission data with data from the visibility meter. Blur and scintillation data are
compared with predictions from standard turbulence model predictions, using Cn
2. In future studies the data will be used
for validation of propagation models such as EOSTAR.
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