DOI: 

Optoelektron. napìvprovìd. teh. 61, 103-124 (2026)


D.V. Pekur, M.S. Kravchenko, H.V. Bystrytskyi, V.I. Kornaga, Yu.Ye. Nikolaienko, B.A. Snopok, V.M. Sorokin. 


ATMOSPHERIC OPTICAL COMMUNICATION LINKS: A REVIEW OF MODERN MODELS OF LIGHT PROPAGATION IN DISPERSED MEDIA OF NATURAL OR ANTHROPOGENIC ORIGIN (review) 


The availability of independent communication channels using atmospheric optical communication links, also referred to as free-space optics (FSO), laser scanning technologies such as LiDAR (Light Detection and Ranging), optical navigation, remote sensing, and multispectral information-transmission channels is an essential feature of an advanced industrial society. However, the efficiency and reliability of open optical channels depend substantially on the physicochemical state of the atmosphere, including the presence of fog, rain, dust, smoke, haze, cloud formations, and other components dispersed in a gaseous environment that is vertically inhomogeneous.

This paper presents an analytical review of modern models of light propagation in atmospheric optical information-transmission channels, particularly in dispersed media of various origins. The combined influence of molecular absorption, Rayleigh scattering, aerosol extinction, Mie scattering, multiple scattering, geometric losses, aperture effects, and medium fluctuations on the atmospheric transmittance of optical radiation is considered.

Special attention is given to the application of atmospheric optical channel models in the development of advanced multispectral optical positioning systems, in which navigation or coordinate information is transmitted through a spatially organized set of optical emitters operating in different spectral ranges. Unlike classical optical communication systems, where the primary goal is to transmit an information flow between a transmitter and a receiver, in multispectral positioning systems the optical signal simultaneously performs informational, identification, and geometrical-navigation functions. The spatial configuration of the sources, their spectral individualization, time codes, amplitude modulation, and angular separation may be used to determine the direction to a beacon, estimate distance, identify a reference point, or form a local optical navigation field.

Under such conditions, the atmospheric medium becomes not merely a loss factor, but an active spectrally selective element of the channel. It affects individual wavelengths differently, changes the ratios between channels, and may disturb the stability of the spatial-code structure of the signal.

The review proposes a three-level classification of models. The first group includes microphysical models of radiation interaction with individual particles or their finite ensembles, including direct calculations based on Maxwell’s equations, Mie theory, transition-matrix methods, the discrete dipole approximation, and related approaches. These methods provide the most detailed description of the local interaction of light with dispersed inhomogeneities, but they require information about their properties, demand significant computational resources, and are usually limited by the number of elements in the ensemble.

The second group includes statistical and radiative-transfer models that describe the atmosphere as a medium with specified particle distributions, temperature, humidity, and pressure profiles, aerosol concentration, and optical thickness. The third group consists of empirical and semi-empirical engineering models that use meteorological visibility, precipitation intensity, humidity, or locally calibrated dependencies to estimate specific attenuation and the optical link margin.

The results of the analytical review of the current state of light-propagation modeling in atmospheric optical communication links indicate that, for the practical design of optical channels, it is advisable to use a hierarchical combination of microphysical, radiative-transfer, and empirical approaches together with local measurements of atmospheric parameters. Such an approach makes it possible to justify the choice of operating wavelength, estimate the link power margin, failure probability, channel availability, and resilience of information-transmission systems under complex weather and aerosol conditions.

This approach is of particular applied importance for multispectral positioning systems, in which coordinate, navigation, or service information is transmitted not through a single monochromatic channel, but through a set of spectrally separated emission channels in the visible, near-infrared, or ultraviolet ranges. In such systems, the atmospheric medium acts not only as a passive signal-attenuation channel, but also as a spectrally selective factor that determines the signal-to-noise ratio, detection range, coding stability, and accuracy of direction finding toward the optical transmitter.

 

Keywords: atmospheric optical communication links (AOCL), free-space optics (FSO), light propagation models, optical transmittance, atmosphere, aerosols, dispersed media, multispectral positioning systems, fog, rain, dust, Mie scattering, radiative transfer equation, visibility, extinction.