The probability distribution of aperture averaged signal intensity from free-space laser optical systems depends on the optical turbulence along the optical path. For most current free-space laser systems, random fluctuations of signal intensity are assumed to be statistically homogeneous and isotropic. Moreover, it is assumed that probability distributions are generally log-normal and that Kolmogorov -5/3 wave number turbulence power law represents the signal intensity data. In this paper, the Kolmogorov model is investigated for an optical path that traverses a complex non-uniform topography. Experimental research is conducted to determine the characteristic behavior of high frequency (2000 Hz) signal intensity data collected over a 2.33 km optical path at the Army Research Laboratory (ARL) Atmospheric Laser Optics Testbed (A_LOT) Facility. Results focus mainly on calculated power spectra and frequency distributions. In addition, a model is developed to calculate optical turbulence intensity (C2/n) as a function of receiving (and transmitting) aperture diameter, log-amplitude variance, and path length. Here, initial comparisons of calculated to measured C2/n data are favorable. It is anticipated that this kind of signal data analysis will benefit laser communication systems development and testing at the ARL.© (2007) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.