Current Optics and Photonics

Optical Society of Korea (한국광학회)
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Impact of the Gain-saturation Characteristic of Erbium-doped Fiber Amplifiers on Suppression of Atmospheric-turbulence-induced Optical Scintillation in a Terrestrial Free-space Optical Communication System

  • Jeong, Yoo Seok (School of Electrical and Computer Engineering, University of Seoul) ;
  • Kim, Chul Han (School of Electrical and Computer Engineering, University of Seoul)
  • Received : 2021.02.01
  • Accepted : 2021.02.24
  • Published : 2021.04.25
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Abstract

We have evaluated the suppression effect of atmospheric-turbulence-induced optical scintillation in terrestrial free-space optical (FSO) communication systems using a gain-saturated erbium-doped fiber amplifier (EDFA). The variation of EDFA output signal power has been measured with different amounts of gain saturation and modulation indices of the optical input signal. From the measured results, we have found that the peak-to-peak power variation was decreased drastically below 2 kHz of modulation frequency, in both 3-dB and 6-dB gain compression cases. Then, the power spectral density (PSD) of optical scintillation has been calculated with Butterworth-type transfer function. In the calculation, different levels of atmospheric-turbulence-induced optical scintillation have been taken into account with different values of the Butterworth cut-off frequency. Finally, the suppression effect of optical scintillation has been estimated with the measured frequency response of the EDFA and the calculated PSD of the optical scintillation. From our estimated results, the atmospheric-turbulence-induced optical scintillation could be suppressed efficiently, as long as the EDFA were operated in a deeply gain-saturated region.

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References

  1. H. Hemmati, Near-earth Laser Communications (CRC Press, Boca Raton, FL, USA, 2009), Chapter 3.
  2. H. Henniger and O. Wilfert, "An introduction to free-space optical communication," Radioengineering 19, 203-212 (2010).
  3. F. Moll, J. Horwath, A. Shrestha, M. Brechtelsbauer, C. Fuchs, L. A. M. Navajas, A. M. L. Souto, and D. D. Gonzalez, "Demonstration of high-rate laser communications from a fast airborne platform," IEEE J. Sel. Area Commun. 33, 1985-1995 (2015). https://doi.org/10.1109/JSAC.2015.2433054
  4. W. Fawaz, C. Abou-Rjeily, and C. Assi, "UAV-aided cooperation for FSO communication systems," IEEE Commun. Mag. 56, 70-75 (2018).
  5. B. Moision, B. Erkmen, E. Keyes, T. Belt, O. Bowen, D. Brinkley, P. Csonka, M. Eglington, A. Kazmierski, N. Kim, J. Moody, T. Tu, and W. Vermeer, "Demonstration of free-space optical communication for long-range data links between balloons on Project Loon," Proc. SPIE 100960, 100960Z (2017).
  6. C. Chen, A. Grier, M. Malfa, E. Booen, H. Harding, C. Xia, M. Hunwardsen, J. Demers, K. Kudinov, G. Mak, B. Smith, A. Sahasrabudhe, F. Patawaran, T. Wang, A. Wang, C. Zhao, D. Leang, J. Gin, M. Lewis, D. Nguyen, and K. Quirk, "Highspeed optical links for UAV applications," Proc. SPIE 10096, 1009615 (2017). https://doi.org/10.1117/12.2256248
  7. S. Bendersky, N. S. Kopeika, and N. Blaunstein, "Atmospheric optical turbulence over land in middle east coastal environments: prediction modeling and measurements," Appl. Opt. 43, 4070-4079 (2004). https://doi.org/10.1364/AO.43.004070
  8. L. C. Andrews, "Aperture-averaging factor for optical scintillations of plane and spherical waves in the atmosphere," J. Opt. Soc. Am. A 9, 597-600 (1992). https://doi.org/10.1364/josaa.9.000597
  9. H. Shen, L. Yu, and C. Fan, "Temporal spectrum of atmospheric scintillation and the effects of aperture averaging and time averaging," Opt. Commun. 330, 160-164 (2014). https://doi.org/10.1016/j.optcom.2014.05.039
  10. E. J. Lee and V. W. Chan, "Part 1: Optical communication over the clear turbulent atmospheric channel using diversity," IEEE J. Sel. Area Commun. 22, 1896-1906 (2004). https://doi.org/10.1109/JSAC.2004.835751
  11. H. Liu, B. Huang, J. C. A. Zacarias, H. Wen, H. Chen, N. K. Fontaine, R. Ryf, J. E. Antonio-Lopez, R. A. Correa, and G. Li, "Turbulence-resistant FSO communication using a few-mode pre-amplified receiver," Sci. Rep. 9, 16247 (2019). https://doi.org/10.1038/s41598-019-52698-1
  12. M. Abtahi, P. Lemieux, W. Mathlouthi, and L. A. Rusch, "Suppression of turbulence-induced scintillation in free-space optical communication systems using saturated optical amplifiers," J. Lightwave Technol. 24, 4966-4973 (2006). https://doi.org/10.1109/JLT.2006.884561
  13. J. Freeman and J. Conradi, "Gain modulation response of erbium-doped fiber amplifiers," IEEE Photonics Technol. Lett. 5, 224-226 (1993). https://doi.org/10.1109/68.196012
  14. K.-H. Kim, T. Higashino, K. Tsukamoto, S. Komaki, K. Kazaura, and M. Matsumoto, "Spectral model of optical scintillation for terrestrial free-space optical communication link design," Opt. Eng. 50, 035005 (2011). https://doi.org/10.1117/1.3557487