Mathematical model of recieved signal for airborne oceanological lidars

Airborne oceanological lidars are usually applied in bathymetry of near-shore ocean water and reconstructing the optical characteristics of ocean water medium. New applications request much more accuracy in oceanological topography and ocean water quality reconnaissance, and need more accurate analytic model of lidar return signals for bathymetry and reconstructing the water quality parameters. Fourier transform method is used to construct the analytic model of bottom return signals and water backscattering signals for monostatic lidar based on analytic beam spread function and ocean medium transfer function given by Mclean, et al., and in this analytic model, the multiple scattering and pulse stretching are considered and discussed, and the calculating method of downwelling irradiance attenuation coefficient and lidar attenuation coefficient is given, and the results indicate that the pulse stretching time can reach tens of nanoseconds in turbid harbor water. The analysis can offer some references for depth and water quality parameter reconstruction algorithms in theorizing.