Two-frequency laser remote sensing in a turbulent atmosphere

The correlation theory of propagation of frequency-separated laser beams in a turbulent atmosphere is developed. Theoretical analysis is based on the equation for the fourth moment of frequency-separated radiation wave fields. For small propagation distances, the results obtained for the frequency correlation of intensity fluctuations are consistent with the predictions of the Obukhov-Rytov method. For large propagation distances, an asymptotic solution of the equation for the fourth moment is used to find the frequency correlation function of intensity fluctuations of wave beams.