Current Optics and Photonics

Optical Society of Korea (한국광학회)
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Experimental Evaluation of Frequency Characteristics of Gain-saturated EDFA for Suppression of Signal Fluctuation in Terrestrial Free-space Optical Communication Systems

  • Yoo Seok, Jeong (School of Electrical and Computer Engineering, University of Seoul) ;
  • Chul Han, Kim (School of Electrical and Computer Engineering, University of Seoul)
  • Received : 2022.11.29
  • Accepted : 2023.01.19
  • Published : 2023.02.25
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Abstract

Frequency characteristics of gain-saturated erbium-doped fiber amplifier (EDFA) are experimentally evaluated to mitigate the optical signal fluctuation induced by atmospheric turbulence in terrestrial freespace optical communication systems. Here, an acousto-optic modulator (AOM) is used to emulate optical signal fluctuations induced by atmospheric turbulence. The waveform which is generated in proportion to the refractive-index structural parameters is used to drive the AOM at various periodic frequencies. Thus, the dependence of the signal fluctuation suppression on the frequency is evaluated. The experiment is conducted using a periodic frequency sweep of the AOM driving voltage waveform and signal input power variation of the amplifier. It is observed that a low periodic frequency and high input signal power effectively suppress the optical signal fluctuation. This study evaluates the experimental results from the high-pass filter and gain-saturation characteristics of the EDFA.

Keywords

Acknowledgement

This work was supported by the 2021 Research Fund of the University of Seoul.

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