Introducing an Optimal Modulation Constellation, Resistant to Atmospheric Turbulence

Document Type : Original Article

Authors

1 IHU

2 ihu

Abstract

One of the communication platforms commonly used in C4I backing layers is the free space optical        communication platform. In this paper, the modulation of polarization is proposed to strengthen the free space optical communication platform against atmospheric perturbations. In this method, instead of using conventional modulation methods such as amplitude, phase or frequency modulations, the polarization states are modulated on the optical beam. Conventional modulation methods are highly sensitive to         turbulence fluctuations. Polarization modulation is highly resistant to the phase noise of laser beams and it maintains the polarization states on a long path in free space. Generally, binary polarization modulation, works better than conventional modulations by about 2 dB or more. More specifically, in this paper, different polarization modulation constellations in Poincaré are plotted and their probability of error is evaluated in different positions. Finally, the optimal states of the constellation are extracted by simulations.
 

Keywords


   [1]      M. Zubair, “Advanced free space optics (FSO): a systems approach,” Contemporary Physics,  vol. 59, pp. 83-83, 2018.##
   [2]      Liu, Chao, et al, “Analysis of Direct Detection And Coherent Detection in Wireless Optical Communication With Polarization Shift Keying,” Conference on Lasers and Electro-Optics/Pacific Rim, Optical Society of America, 2009.##
   [3]      H. Samimi and P. Azmi, “Subcarrier intensity modulated free-space optical communications in K-distributed turbulence channels,” Journal of Optical Communications and Networking, vol. 2, no. 8, pp. 625-632, 2010.##
   [4]      P. Krishnan and D. S. Kumar, “Performance analysis of free-space optical systems employing binary polarization shift keying signaling over gamma-gamma channel with pointing errors,” Optical Engineering, vol. 53, no.7, p. 076105, 2014.##
   [5]      X. Tang, Z. Ghassemlooy, W. O. Popoola, and C. G. Lee, “Coherent Polarization Shift Keying Modulated Free Space Optical Links Over A Gamma-Gamma Turbulence Channel,” American Journal of Engineering and Applied Sciences vol. 4, no. 4, pp. 520-530, 2011.##
   [6]      X. Tang, Z. Ghassemlooy, W. O. Popoola, and C. G. Lee, “Coherent Optical Binary Polarisation Shift Keying Heterodyne System in The Free-Space Optical Turbulence Channel,” IET Microwaves, Antennas & Propagation, vol. 5, no. 9, pp.                                    1031-1038, 2011.##
   [7]      P. Kundu, M. J. Islam, and I. J. Talukder, “Performance Analysis of Binary Polarization Shift Keying OCDMA FSO System under Different Atmospheric Conditions,” 2nd International Conference on Electrical & Electronic Engineering (ICEEE), 2017.##
   [8]      K. S. Hou and J. Wu, “A Differential Coding Method for The Symmetrically Differential Polarization Shift-Keying System,” IEEE Transactions on Communications, vol. 50, pp. 2042-2051, 2002.##
   [9]      J. Grosinger, “Investigation of Polarization Modulation in Optical Free Space Communications Through The Atmosphere,” Master Thesis, Univ.Vienna, 2008.##
[10]      E. Collett, “Polarized Light in Fiber Optics,” SPIE, 2003.##
[11]      S. Ishimura and K. Nishimura, “Blind polarization demultiplexing algorithm for multi-level modulation formats in stokes vector direct detection systems,” Opto-Electronics and Communications Conference (OECC) and Photonics Global Conference (PGC), 2017.##
[12]      X. Tang, Z. Ghassemlooy, W. O. Popoola, and C. G. Lee, “Coherent Heterodyne Multilevel Polarization Shift Keying With Spatial Diversity in a Free-Space Optical Turbulence Channel,” Journal of Lightwave Technology, vol. 30, no. 16, pp.                 2689-2695, 2012.##
[13]      Y. Ito and K. Ohuchi, “Performance of multilevel differential polarization shift keying with estimation of inclined polarization axes over atmospheric turbulence channel,” 27th International Telecommunication Networks and Applications Conference (ITNAC), 2017.##
[14]      P. Shi, H. Huan, and R. Tao, “Waveform design for higher-level 3D constellation mappings and its construction based on regular tetrahedron cells,” Science China Information Sciences, vol. 58, no. 8, pp. 1-12, 2015.##
  • Receive Date: 02 October 2019
  • Revise Date: 11 January 2020
  • Accept Date: 01 February 2020
  • Publish Date: 22 August 2020