The paper defines a physical parameter—the improving ratio of light intensity undulation variance,and its relation to such parameters as emission aperture,spread distance,aperture space and beam quality,etc.

On the basis of Rytov抯 variance and using Andrews?model, log-intensity variance for partial coherent beam transmitting through strong turbulence is deduced in this paper.

A series of measurments of the irradiance scintillation of a He Ne laser beam propagating over complex terrain were carried out.

We carried out a series of measurments of the irradiance scintillation of a He Ne laser beam propagating through a real turbulent atmosphere in a whole year.

The influence of atmospheric turbulence on multiple-beam atmospheric laser communication and the characteristics of optical intensity fluctuation after the multiple beams passing through atmospheric turbulence are analyzed theoretically.

The statistical characteristics of the laser log-intensity fluctuation and beam pattern in a turbulent atmosphere were studied systematically.

The intermittency characteristics of laser irradiance scintillation in a turbulent atmosphere were checked qualitatively via the wavelet transformation, and a quantitative description method based on the singularity measure analysis was adopted to study the intermittency in a systematic manner.

From the relationship between the scaling exponent and the scintillation index we found that the characteristic of the power spectrum is different for the winter and the summer.

Based on the theory proposed by Walls et al, an experimental scheme of quantum non demolition (QND) measurement for intensity difference fluctuations is put forward, which is realized though a nondegenerate optical parametric amplifier.