Backscatter suppression via blind signal separation for a 532 nm underwater chaotic lidar rangefinder

Blind signal separation is applied to suppress backscatter for a 532 nm chaotic lidar underwater rangefinder. When operating in turbid waters, chaotic lidar returns contain information for both submerged objects and an optical backscatter “clutter” component. The statistical digital signal processing technique of blind signal separation (BSS) is applied to dynamically measure and cancel out the backscatter component before computing range to the desired object. Results from simulations and laboratory experiments are presented to demonstrate the combined chaotic/BSS approach. The chaotic/BSS approach extends operating range by almost 40% and achieves centimeter-order range accuracy. Receiver operating curves are simulated for the chaotic/BSS approach, which show convergence towards the ideal classifier in several conditions of interest.