Blue-green propagation through clouds

Optical communications in the atmosphere, space and underwater was investigated. The performance of a space to Earth/underwater link through the adverse atmospheric propagation channel is of paramount importance. The presence of clouds along the propagation path scatter the blue-green radiation and cause spatial, angular, and temporal spreadings of the beam. This condition decreases the peak power at the receiver by both multipath time delays, and spatial spreading and also increases the apparent source size. Performance may be seriously degraded. This effect are somewhat compensated for by adapting the receiver; increasing the field of view of the receiver to accept the scattered radiation. The temporal, spatial, and angular spreading of a blue-green pulse through clouds and fogs are measured as a function of optical thickness and receiver field of view.