BER Analysis of Cooperative Systems in Free-Space Optical Networks

Free-space optical (FSO) communication suffers from several challenges in practical deployment; the major of them is fading or scintillation. To overcome such limitations, spatial diversity based on MIMO techniques has been proposed for FSO systems. User cooperation diversity is a new form of spatial diversity which is introduced to overcome some limitations of MIMO structures. Although the promising effects of cooperative transmission in RF communications have greatly been considered so far, there have been a few notable research on cooperative diversity in FSO. In this paper, we first consider a 3-way FSO communication setup, in which the cooperative protocol can be applied to achieve the spatial diversity without much increase in hardware, compared to their regular transmission. Then, we introduce different cooperative strategies and investigate their bit error rate (BER) performance in the presence of shot noise, using the photon-count method. We compare the results with those of the direct path link (non-cooperative scheme) and the two transmitters case, which are the upper and lower bounds on the BER of the cooperative scheme, respectively. The results illustrate the advantages of cooperation under a number of different scenarios for realistic SNRs.

[1]  Salah Bourennane,et al.  Channel coding and time-diversity for optical wireless links. , 2009, Optics express.

[2]  Murat Uysal,et al.  Cooperative diversity over log-normal fading channels: performance analysis and optimization , 2008, IEEE Transactions on Wireless Communications.

[3]  Aria Nosratinia,et al.  Diversity through coded cooperation , 2006, IEEE Transactions on Wireless Communications.

[4]  Isaac I. Kim,et al.  Scintillation measurements performed during the limited-visibility lasercom experiment , 1998, Photonics West.

[5]  Mark Leeson,et al.  Principles of Lightwave Communications , 1996 .

[6]  B. Strickland,et al.  Effects of fog on the bit-error rate of a free-space laser communication system. , 1999, Applied optics.

[7]  R. Stephenson A and V , 1962, The British journal of ophthalmology.

[8]  Mohsen Kavehrad,et al.  BER Performance of Free-Space Optical Transmission with Spatial Diversity , 2007, IEEE Transactions on Wireless Communications.

[9]  Gregory W. Wornell,et al.  Cooperative diversity in wireless networks: Efficient protocols and outage behavior , 2004, IEEE Transactions on Information Theory.

[10]  Fang Liu,et al.  Bootstrapping free-space optical networks , 2006, IEEE Journal on Selected Areas in Communications.

[11]  V.W.S. Chan,et al.  Free-Space Optical Communications , 2006, Journal of Lightwave Technology.

[12]  Joseph M. Kahn,et al.  Free-space optical communication through atmospheric turbulence channels , 2002, IEEE Trans. Commun..

[13]  Aaas News,et al.  Book Reviews , 1893, Buffalo Medical and Surgical Journal.

[14]  Murat Uysal,et al.  Error rate performance analysis of coded free-space optical links over gamma-gamma atmospheric turbulence channels , 2006, IEEE Transactions on Wireless Communications.

[15]  Cyril Leung,et al.  Efficient ARQ schemes with multiple copy decoding , 1992, IEEE Trans. Commun..

[16]  D. A. de Wolf,et al.  Strong irradiance fluctuations in turbulent air: plane waves* , 1973 .

[17]  Etty J. Lee,et al.  Part 1: optical communication over the clear turbulent atmospheric channel using diversity , 2004, IEEE Journal on Selected Areas in Communications.

[18]  Harry Leib,et al.  Evaluating the performance of convolutional codes over block fading channels , 1999, IEEE Trans. Inf. Theory.

[19]  Heinz Willebrand,et al.  Free Space Optics: Enabling Optical Connectivity in Today's Networks , 2001 .

[20]  L. Andrews,et al.  Laser Beam Scintillation with Applications , 2001 .

[21]  Murat Uysal,et al.  Relay-Assisted Free-Space Optical Communication , 2007, 2007 Conference Record of the Forty-First Asilomar Conference on Signals, Systems and Computers.

[22]  Joseph M. Kahn,et al.  Performance bounds for coded free-space optical communications through atmospheric turbulence channels , 2003, IEEE Trans. Commun..

[23]  Elza Erkip,et al.  User cooperation diversity. Part II. Implementation aspects and performance analysis , 2003, IEEE Trans. Commun..

[24]  Debbie Kedar,et al.  Urban optical wireless communication networks: the main challenges and possible solutions , 2004, IEEE Communications Magazine.

[25]  Shu Lin,et al.  Error Control Coding , 2004 .

[26]  Maïté Brandt-Pearce,et al.  Free-space optical MIMO transmission with Q-ary PPM , 2005, IEEE Transactions on Communications.

[27]  Elza Erkip,et al.  User cooperation diversity. Part I. System description , 2003, IEEE Trans. Commun..