Study Of The Character Of Blue-Green Laser Transmission Through Rough Sea Surface

In the blue-green laser communication system to submarine, optical channels of laser communication system consist of air, sea, air to sea surface. This sea surface is an important component of the transmission channel from atmosphere to ocean. It has significant influence of sea surface on the air-sea communication system and radar detection performance.In this paper two typical sea power spectrums are given. The methods for modeling sea surfaces are outlined, including statistical models and fractal models. One dimensional and two dimensional rough sea surfaces are simulated. When a laser beam propagates from air into sea, complex process of reflection and refraction are generated in the rough air/sea interface. The relations of laser beam transmission with different incidence angle and wind speed are analyzed. The sea/air interface is fluctuant and influenced by wind speed or other acting force inducing inclination. Laser beams through the interface propagation direction becomes more complex bring on spreading and wandering, thus causing the whole object power attenuation. With the theory of GO and the simulation of sea surface, the transmission characters for a laser beam transmitting through rough sea surface are simulated and analyzed. This paper presents the transmission delay of underwater laser pulse with the aid of the small-angle approximation, caused by the scattering effects in the sea.The study methods and results in this dissertation have important significance for improving performance of communication, detection and imaging under seawater.