Physical and statistical modeling of attenuation due to atmospheric hydrometeors on free-space optical links at 850 and 1550 nm

摘要

Atmospheric hydrometeors such as rain and fog may cause attenuation of an optical signal and degrade the performanceof free-space optical (FSO) systems. For efficient design of the FSO links, attenuation characteristics must be predictedby sufficiently reliable models that have been tested on experimental data. A long term experiment on the FSO linksoperating at 850 and 1550 nm wavelengths is conducted in Prague. The path lengths are 100 and 853 m. Received powerfluctuations on the FSO links and relevant meteorological quantities such as rain intensity and liquid water content of fogare measured simultaneously. The relationships between the physical parameters of hydrometeors and path attenuationare analyzed and compared with theoretical relations derived using the Mie scattering theory together with some naturalassumptions about the physical properties of scattering particles such as droplet size distribution of different types ofhydrometeors. Long term statistics of attenuation are obtained and availability performance of the experimental FSOlinks is assessed. The method for predicting attenuation statistics based on physical and statistical models is introducedand the errors of the proposed models with respect to measured data are analyzed. The models are compared with theexisting empirical relationships derived from other FSO experiments and differences are discussed.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.