Statistical model for free-space optical coherent communications using adaptive optics
In this paper we present a new model for describing the turbulence-induced fading that uses the representation of the phase in the aperture plane as a collection of random ""cells"". This model serves as input to calculate the probability density function of fading intensity. The model has two parameters: phase variance and number of wavefront cells. We derive expressions for the signal-to-noise ratio in the presence of atmospheric turbulence and adaptive optics compensation. We estimate symbol error probabilities for M-ary phase shift keying and evaluate the performance of coherent receivers as a function of the normalized aperture and the number of actuators on the deformable mirror or the number of compensated modes. We perform numerical simulations of the fading intensity for different uncompensated and compensated scenarios and we compare the results with the proposed model.