Off-axis detection of pulsed laser beams: simulation and measurements in the lower atmosphere

Laser beams can be detected when propagating in the atmosphere, even if they are not pointed straight on the sensors. Mie scattering on aerosols allows to detect off-axis beams and to localize the source thanks to their geometric, spectral and temporal properties. In the recent years, Onera has conducted both theoretical and experimental studies to detect off-axis non cooperative pulsed laser beams in the lower atmosphere. Some simulations are presented, based on propagation and scattering physics. Experimental results are discussed.