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Impact of Temporary Link Blockage on Ergodic Capacity of FSO System

  • Petkovic, Milica I. (Faculty of Technical Sciences, University of Novi Sad) ;
  • Djordjevic, Goran T. (Faculty of Electronic Engineering, University of Nis)
  • Received : 2017.07.31
  • Accepted : 2018.03.05
  • Published : 2018.06.01
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Abstract

Free-space optical (FSO) systems have attracted much attention from both research and application perspectives owing to their many benefits, such as license-free operation, low-cost, and high data rates. This paper investigates the ergodic capacity of FSO systems, which is an important metric of system performance. The stochastic temporary laser-beam blockage, pointing errors, and atmospheric turbulence are simultaneously considered. The results illustrate that the link blockage causes a decreased ergodic capacity. We show that to maximize the ergodic capacity, there is an optimal value of the laser-beam radius at the waist, which largely depends on pointing errors; however, it is independent of the atmospheric turbulence and the probability of link blockage.

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References

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