Enhancement of reliability and security in a time-diversity FSO/CDMA wiretap channel

Due to atmospheric turbulence, the reliability and security of free space optical (FSO) communication is seriously affected. In this paper, we propose a new FSO wiretap channel model based on a time-diversity scheme and optical code division multiple access (OCDMA). At the receiving end, the legitimate user employs time-diversity reception by matched optical decoders, while an eavesdropper uses a random optical decoder for eavesdropping. Using an avalanche photodiode (APD) photon counting model, bit error rate (BER) performances of legitimate and eavesdropping users are theoretically analyzed under different turbulence and diversity. Based on the binary asymmetric channel model, the physical layer security performance of the time-diversity FSO/CDMA wiretap channel is evaluated by using security capacity. With the increase of time-diversity order, the reliability and security performances of FSO/CDMA wiretap channel are improved. Simulation results show that the performances of the time-diversity FSO/CDMA wiretap channel are better than those of a non-diversity FSO/CDMA system.

[1]  Anh T Pham,et al.  Performance improvement of FSO/CDMA systems over dispersive turbulence channel using multi-wavelength PPM signaling. , 2012, Optics express.

[2]  Soon Xin Ng,et al.  Design and Security Analysis of Quantum Key Distribution Protocol Over Free-Space Optics Using Dual-Threshold Direct-Detection Receiver , 2018, IEEE Access.

[3]  Subrat Kar,et al.  Performance of 1-D and 2-D OCDMA systems in presence of atmospheric turbulence and various weather conditions , 2017, IET Commun..

[4]  George S. Tombras,et al.  Performance analysis of free-space optical communication systems over atmospheric turbulence channels , 2009, IET Commun..

[5]  Mina Eghbal,et al.  Security enhancement in free-space optics using acousto-optic deflectors , 2014, IEEE/OSA Journal of Optical Communications and Networking.

[6]  Hossam M. H. Shalaby,et al.  Complexities, error probabilities, and capacities of optical OOK-CDMA communication systems , 2002, IEEE Trans. Commun..

[7]  Jawad A. Salehi,et al.  Atmospheric optical CDMA communication systems via optical orthogonal codes , 2006, IEEE Transactions on Communications.

[8]  Seyed Mohammad Sajad Sadough,et al.  On Secure Free-Space Optical Communications Over Málaga Turbulence Channels , 2017, IEEE Wireless Communications Letters.

[9]  R. Tyson.  Bit-error rate for free-space adaptive optics laser communications. , 2002, Journal of the Optical Society of America. A, Optics, image science, and vision.

[10]  Anjan Kumar Ghosh,et al.  Performance of free-space optical link with wavelength diversity over exponentiated Weibull channel , 2016 .

[11]  Tomoaki Ohtsuki,et al.  Performance analysis of atmospheric optical PPM CDMA systems , 2003 .

[12]  Hyuck M. Kwon,et al.  Optical orthogonal code-division multiple-access system .I. APD noise and thermal noise , 1994, IEEE Trans. Commun..

[13]  Joseph M. Kahn,et al.  Sensitivity Improvement in 100 Gb/s-per-Wavelength Links Using Semiconductor Optical Amplifiers or Avalanche Photodiodes , 2016, Journal of Lightwave Technology.

[14]  Mohamed B. El Mashade,et al.  Performance Characterization of Spatial Diversity Based Optical Wireless Communication over Atmospheric Turbulence Channels , 2018 .

[15]  Stuart D. Milner,et al.  Characterization of time delayed diversity to mitigate fading in atmospheric turbulence channels , 2005, SPIE Optics + Photonics.

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

[17]  N. Zhang,et al.  Dielectric-Grating-Coupled Surface Plasmon Resonance From the Back Side of the Metal Film for Ultrasensitive Sensing , 2016, IEEE Photonics Journal.

[18]  F. Javier Lopez-Martinez,et al.  Physical-Layer Security in Free-Space Optical Communications , 2015, IEEE Photonics Journal.

[19]  Murat Uysal,et al.  Survey on Free Space Optical Communication: A Communication Theory Perspective , 2014, IEEE Communications Surveys & Tutorials.

[20]  Masahide Sasaki,et al.  Numerical Study on Secrecy Capacity and Code Length Dependence of the Performances in Optical Wiretap Channels , 2015, IEEE Photonics Journal.

[21]  Qian Huang,et al.  Performance analysis of FSO/CDMA system based on binary symmetric wiretap channel , 2019, IET Commun..

[22]  Idelfonso Tafur Monroy,et al.  Hybrid optical CDMA-FSO communications network under spatially correlated gamma-gamma scintillation. , 2016, Optics express.