4. Estimating performance

Determining the performance of a lidar imager in seawater is made tricky by the presence of multiple scatterings, which tend to degrade resolution, but nevertheless increase range compared to a simple prediction taking into account only the global attenuation coefficient c. One possible approach to predicting performance is to calculate it to first order using the lidar equation, and then make a correction taking into account experimental results and Monte-Carlo type simulations.

• The light power backscattered towards the detector by the target, assumed to be purely Lambertian with albedo ρ, located at distance x from the transmitter/receiver assembly and intercepting the entire beam, has the expression : $P=P_{\text{o}}\rho \frac{R_{\text{d}}^2}{x^2}{\text{e}}^{-2cx}\text{ (équation du lidar) }$

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