Atmospheric optical turbulence causes signal loses in laser propagation. Here we present vertical measurements of optical turbulence taken in London's financial district. Additionally, we demonstrate a method of modelling atmospheric states in simulation from the measured data. From this we derive the predicted system performance of an optical downlink from a satellite in low Earth orbit (LEO) to ground in the atmospheric conditions observed on the night. We also present the improvements in performance with the addition of adaptive optics at the receiver end.
Understanding the vertical distribution of atmospheric optical turbulence is essential for the global-scale implementation of free-space optical communications (FSOC). Maintaining communications with satellites in low-Earth orbit (LEO) requires tracking over changing elevation angles. Decreasing elevation angles in optical communication links due to a satellite's orbit attributes to significant signal losses due to increased propagation lengths and strong turbulence. Here we present the variance in atmospheric optical turbulence measurements in the form of scintillation index and Fried parameter measured on the Island of La Palma. These measurements are taken between elevation angles of 90 • and 0 • with reference measurements being taken concurrently at zenith to remove temporal variations. The results are compared with the existing theory.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.