Characteristics of lidar returned signals from wavy water surface

There have been many mature results about reflection and refraction characteristic on medium surface of Gaussian beam, which are verified by practical applications. But, those are limited to regular medium surface such as plane and sphere. When the medium surface is wavy, the reflection and refraction characteristic is greatly different comparing with regular one. In the paper, according to the statistical description of direction distribution on wavy surface by Cox, we have set up a physical model of reflection of laser beam on wavy surface, derived that a beam reflected by wavy surface is also a Gaussian beam when the incident beam is a Gaussian beam, and set up the relationship between Gaussian beam’s light spot size and wind speed over sea surface. According to the wave model on the water surface, the returned laser power expression for the airborne laser bathymetry is derived from. The influence of the wavy water surface, the field of view for the IR received system on returned laser power is discussed.