An Adaptive Modulation Scheme for Coded Free-Space Optical Systems

Hariq S. H., Odabasioglu N., UYSAL M.

19th European Conference on Networks and Optical Communications (NOC), Milan, Italy, 4 - 06 June 2014, pp.132-135 identifier identifier

  • Publication Type: Conference Paper / Full Text
  • Volume:
  • Doi Number: 10.1109/noc.2014.6996841
  • City: Milan
  • Country: Italy
  • Page Numbers: pp.132-135
  • Istanbul University Affiliated: Yes


For very slowly-varying fading channels as in the case of atmospheric turbulence-induced fading, it is possible to reliably estimate the channel state information and send it back to the transmitter. The transmitter can use this information to vary the transmission parameters such as power, modulation size, code rate etc according to the channel conditions. This is known as link adaptation. In this paper, we consider a turbo-coded free-space optical (FSO) system with M-ary pulse position modulation over log-normal turbulence channels and propose an adaptive modulation scheme under peak power constraints. Our simulation results demonstrate significant performance improvements of the proposed adaptive scheme over non-adaptive counterparts.