The calculation of the intensity of rain causing digital communication failure through the atmospheric channel
At present, interest in open optical communication lines (OOLS) is resuming in Russia in connection with connection to world information communications. OOLS successfully competes with fiber-optic communication lines (FOCL) in terms of time and cost for establishing communications. A significant drawback of OOLS is the dependence of the quality of information transmission on weather conditions on the highway. The performance of an open communication channel is determined by the distribution environment. If the propagation medium is different from free space (outer space), the structure of the electromagnetic wave is distorted. These distortions are determined by the interaction of the wave with medium inhomogeneities. When propagating in the atmosphere, amplitude and spatial distortions of the structure of the OALS laser beam transmitting information occur. Amplitude effects manifest as temporary changes in the field, leading to a decrease in power, fluctuations in power, and frequency filtering of radiation and limit the communication range. Spatial effects appear as a change in the direction of propagation and distortion of the beam in the direction transverse to the wave front. The latter leads to a limitation of the speed of information transfer. The propagation of optical radiation in the atmosphere is accompanied by a wide range of phenomena. At the same time, none of these phenomena is manifested separately. By qualitative characteristics, these phenomena can be divided into the following main groups: refraction of rays, energy absorption by atmospheric gases and aerosols, energy dissipation by aerosol particles and fluctuations in air density, fluctuations of optical radiation parameters caused by atmospheric turbulence. The article provides a formula for calculating and the results of estimating the maximum rain intensity, made on the example of a communication line between different buildings of SIBSUTIS, leading to a communication failure.