Effect of atmospheric turbulence on heterodyne lidar performance.

The effect of atmospheric turbulence on heterodyne lidar performance is studied by use of scattering theory. A theoretical analysis is carried out for both bistatic and monostatic lidar systems with independently variable transmitter and receiver parameters in regimes of weak and strong intensity fluctuations. The conditions of validity of a diffuse target model for description of the optical wave scattering by aerosols in a turbulent atmosphere are presented. The equations for signal power degradation and the conditions under which the time-averaged output of a heterodyne lidar does not depend on either turbulent conditions of propagation along the path or the transmitter parameters, including transmitter coherence length, are obtained. A physical interpretation of these results is given, and a comparison with the data of previous theories is made.