Physical Modeling of the Effects of Atmospheric Electricity and Lightning on Optical Distributed Telecommunication Systems

—Results of physical modeling of the effects of atmospheric electricity and lightning on fiber-optic communication lines are presented. The thunder-storm impact was simulated using the GROZA installation, which allows creation of charged aerosol clouds. The installation was equipped with an optical device, which was used to simulate the signal transmitted via an optical cable and record the power of optical radiation. In the center of the coil of a fully dielectric optical cable, a grounded rod electrode was placed that received discharges from a manmade thunderstorm cloud, due to which the optical-signal power and discharge parameters were simultaneously recorded. Two series of experiments were performed at a cable length of 5 km and 50 m. A decrease in the power of the signal transmitted over a 5-km fiber-optic cable with an increase in the potential of a manmade thunderstorm cloud was revealed, probably due to the Kerr effect. An optical cable with a length of 50 m exhibited a different pattern of changes in the power of the optical signal. In the process of discharge from a charged aerosol cloud into the center of a cable coil, a rapid, abrupt change in the power of the optical signal was observed. It is assumed that this change is due to the magneto-optical Faraday effect. The parameters of the discharge and the change in the power of the optical signal are compared, and a trend toward an increase in the variation of the optical signal power with an increase in the amplitude of the discharge current pulse is shown.