Radar modulation on optical carrier for target detection in sea-water

Summary form only. The sensitivity of a LIDAR system (light detection and ranging) and the contrast of immersed targets are strongly reduced by the volume backscattering clutter. To overcome this problem it has been suggested to use a radar modulation in association with an optical carrier at 532 nm (minimum absorption for sea-water): using a pulse laser source will allow one to keep the benefits of the reduction of volume backscattering clutter. Such a technique improves the detection of underwater targets and is justified by the low-pass transfer function shown by sea-water in backscattering configuration.