Stanislav Sokolov,
Institute of Radio and Information Systems (IRIS), Vienna, Austria

DOI: 10.36724/2664-066X-2023-9-2-26-29

SYNCHROINFO JOURNAL. Volume 9, Number 2 (2023). P. 26-29.


Long-distance communication lines are optical fiber lines in most cases now. This moment PM QPSK system (polarization-division multiplex with quadrature phase shift keying) appear. Polarization-division multiplex uses a fact that the optical signal can propagate as two orthogonal polarized modes that allows to use the modes independently and makes it possible to double carrier capacity (together with already other used multiplex system). Two orthogonal waves using in the same fiber can cause problems during lightning discharges close by cable line. Under influence of external cross electrical field (or longitudinal magnetic) the polarizations plane of lights wave can turns on angle, which depends on field value, light path length upon field action and fiber sensitivity. During the influence of external electromagnetic field issue a part of one polarization signal can pass to other orthogonal plane and it will perceive wrongly. The Wavelength Division Multiplexing (WDM) systems development with increasing number of carriers brought to transmission in the same transparency window some tens or hundreds waves. They are shifted relative to each other for some parts of nanometers during the lightning stroke. Therefore the polarization plane rotation will be different for each wave (other conditions being equal): the short waves rotated greater than the long waves. On input of optical amplifier there will be packet of waves with different polarizations, and it can produce problems to filters, optical insulators and amplifiers, to Raman amplifiers specially, which are sensitive to polarization. It is known that short and long waves are moving with different velocity as refraction index depends upon wave length. Usually the rotation angle quantity is small if resistivity of earth near cable is not heavy and if equipment does not contain sensitive to PMD (Polarization Modes Dispersion). This phenomenon passes usually unnoticed. But sometimes with strong thunderstorm and lightning stroke at a short distance the polarization plane rotation can exceed 45º or even 90º. Hereby, it is possible the complex electrical and magnetic fields influence during thunderstorm on orthogonal polarization using, that can lead to additional component appearance in orthogonal axes and to signal reception error. Error level for year is estimated.

Keywords Optical Cable,Wavelength Division Multiplexing, Polarization


[1] S.A. Sokolov, “Kerr and Faraday effects in an optical cable,” Telecommunications. No. 4, 1996.

[2] S.A. Sokolov, “The emergence of polarization mode dispersion under the influence of lightning discharges,” Telecommunications. No. 11, 2004.

[3] J.R. Dwyer et al., “X-ray bursts associated with leader steps in cloud-to-ground lightning,” Geophysical Research Letters. Vol.32, L01803, 2005.

[4] J.R. Dwyer et al., “A ground level gamma-ray burst observed with rocket-triggered lightning,” Geophysical Research Letters. Vol.31, L05119, 2004.

[5] S.A. Sokolov, “The impact of lightning discharges on optical cables in mountainous areas and near high-rise buildings,” First Mile. No. 2, 2013.

[6] S.A. Sokolov, “Electromagnetic fields inside and near a building,” Science-intensive technologies in space research of the Earth,” 2014. Vol. 6. No. 5, pp. 28-32.

[7] S.A. Sokolov, “Possible risk of incorrect reception of information via an optical cable during lightning discharges,” Science-intensive technologies in space research of the Earth,” 2014. Vol. 6. No. 3, pp. 22-25.

[8] S. A. Sokolov, A. L. Zubilevich and B. N. Morozov, “Communication Disturbances In Moving Objects,” 2019 Systems of Signals Generating and Processing in the Field of on Board Communications, Moscow, Russia, 2019, pp. 1-6, doi: 10.1109/SOSG.2019.8706767.

[9] K. Ivanov and P. Uzunov, “Coupled Finite Element Analysis of Optical Ground Wire for Overhead Power Lines,” 2022 8th International Conference on Energy Efficiency and Agricultural Engineering (EE&AE), Ruse, Bulgaria, 2022, pp. 1-4, doi: 10.1109/EEAE53789.2022.9831238.