A model for a partially coherent Gaussian beam in atmospheric turbulence with applications for lasercom and LIDAR systems.

摘要

Today, free-space laser communications and laser radars (LIDAR) are among the most important and fast developing applications of the theory of electromagnetic wave propagation in random media. Although generally based on different principles of construction and operation, these two kinds of systems involve one common problem: propagation of partially coherent beams through atmospheric turbulence.; The design of either lasercom or LIDAR systems requires a reliable but tractable theoretical foundation (analytical model) for the calculation of phase and/or intensity statistics of the wave at the receiver under a wide range of atmospheric conditions. All rigorously developed results existing in the literature are unfortunately constrained to certain regimes (weak atmospheric fluctuations, quasi-incoherent sources, fully diffuse targets, etc.). Moreover, there are no analytic results describing the behavior of partially coherent waves in moderate-to-strong fluctuations.; The goals of this study were determined by the problems discussed above. Namely they are: establishing a theoretical model for the statistical description pf a partially coherent beam propagating in rotationally symmetric optical systems of various complexity in the presence of atmospheric turbulence and its comparison with existing models; applying the model for estimation of lasercom link performance and for target characterization by laser radars.