Free-Space Optics: A Shifting Paradigm in Optical Communication Systems in Difficult Terrains

  • PayalEmail author
  • Suresh Kumar
Conference paper
Part of the Advances in Intelligent Systems and Computing book series (AISC, volume 1045)


Free-space optical (FSO) communication is a high-speed technology that can be used to promote rapid deployment of ubiquitous wireless service at the geographical locations such as hilly areas, where radio frequency (RF) technology is inaccessible and laying of optical fibers is not physically and economically viable. FSO has gained significant importance due to several advantages such as extremely high bandwidth, unlicensed spectrum allocation, reduced power consumption about half of the RF, ease of deployment, improved channel security, and reduced size which is one-tenth of the diameter of RF antenna. However, along with many advantages of FSO, atmosphere poses a serious limitation on its performance causing absorption, scattering, scintillations, and atmospheric turbulences. This paper presents a comprehensive review of FSO technology. FSO basics along with its advantages over RF are described so that readers can easily get the concept of shifting from RF to optical communication. Further, the paper also highlights the challenges faced by FSO, various models to characterize atmospheric turbulence fluctuations, issues, and methods to overcome them.


On–off keying (OOK) Subcarrier intensity modulation (SIM) Pulse position modulation (PPM) FSO Optical fiber cable (OFC) Line of sight (LOS) RF 


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© Springer Nature Singapore Pte Ltd. 2020

Authors and Affiliations

  1. 1.University Institute of Engineering and TechnologyMaharshi Dayanand UniversityRohtakIndia

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