Efficient Adaptive Equalization for Wireless Optical Communication Systems

Document Type : Original Article

Authors

1 Communication Department Faculty of Electronic Engineering El-Menoufia University El-Menoufia, Egypt

2 Communication Department Faculty of Electronic Engineering El-Menoufia University El-Menoufia, Egypt.

Abstract

Optical Wireless Communication (OWC) system is used in many applications to transmit and receive light waves via free space. It is a perfect solution when it is difficult to use optical fibers system due to its cost or constructing difficulty.  On the other hand, FSO systems suffer from the physical impairments in free space channel such as clouds, fog, snow and rain that may degrade the transmission quality. This paper presents an efficient adaptive equalization scheme for OWC systems to mitigate the effect of ISI due to atmospheric impairments. It is based on using the Recursive Least Squares (RLS) equalizer with Activity Detection Guidance (ADG) and Tap Decoupling (TD).  The simulation results prove that the proposed scheme gives a very good performance to mitigate the problem of ISI in OWC systems. In addition, the results prove that the RLS algorithm has a fast convergence rate, which recommends it for nonstationary channel models (wireless communication environments).

Keywords

References

[1]     A. S. Hamza, J. S. Deogun and D. R. Alexander, "Classification Framework for Free Space Optical Communication Links and Systems," in IEEE Communications Surveys & Tutorials, vol. 21, no. 2, pp. 1346-1382, Second quarter 2019.
[2]     Zabih Ghassemlooy, HoaLe Minh, Sujan Rajbhandari, Joaquin Perez, and Muhammad Ijaz “Performance Analysis of Ethernet/Fast-Ethernet Free Space Optical Communications in a Controlled Weak Turbulenc Condition”. Journal of light wave technology. vol. 30, no. 13, pp. 1-7, 2012.
[3]     Zhu, X, Kahn J. M, “Free Space Optical Communications Through Atmospheric Turbulence Channels”, IEEE Transactions on Communications, vol. 50, no. 8, August 2002.
[4]     Hemmati H, ”, John Wiley and Sons,  “Deep Space Optical Communications”, Proceedings of the IEEE, vol. 99, no. 11, pp. 2020 – 2039, 2011.
[5]      Davide M. Forin, G, and G.M. TosiBeleffi, “Free Space Optical Technologies”. SPIE 4214, Optical Wireless Communications III, Conference vol. 4214, no. 72, pp. 1-41, 2001.
[6]      Barua, Bobby and S. Majumder. “Bit Error Rate Analysis of an OFDM Subcarrier Modulated FSO Link with Optical Intensity Modulation and a Direct Detection Receiver.” (2019).
[7]      S. Arnon, D. Sadot, and N. S. Kopeika, “Analysis of Optical Pulse Distortion Through Clouds for Satellite to Earth Adaptive Optical Communication, ”J.  Mod. Opt., vol. 41, no. 8, pp 1591–1605, 1994.
[8]       M. R. S. K. D. Tarek Hasan-Al-Mahmud, "Performance Analysis of Best suited Adaptive Equalization Algorithm for Optical Communication," JOURNAL OF TELECOMMUNICATIONS, vol. 1, no. 2, pp. 1-8, March 2010.
[9]     R. L. Phillips and L. C. Andrews, “Measured Statistics of Laser-Light Scattering in Atmo-Spheric Turbulence,” J. Opt. Soc. Am., vol. 71, pp. 1440-1445, Dec. 1981.
[10] Fatma Benkhelifa, ZouheirRezki, and Mohamed-Slim Alouini,  “Low SNR Capacity Of FSO Links Over Gamma-Gamma Atmospheric Turbulence Channels”, Communications Letters, IEEE  vol. 17,  no. 6 , pp. 1264 - 1267, 13 May 2013.
[11] Xuan Tang “Polarization Shift Keying Modulated Free Space Optics Communication Systems”, American J. of Engineering and Applied Sciences, vol. 4, no 4, 520-530, 2011.
[12]Garima Malik, Amandeep Singh Sappal” Adaptive Equalization Algorithms”. International Journal of Advanced Computer Sciences and Applications. vol. 2, no. 3, 2011.
[13] Raymond Wang1, et al,” Comparing RLS and LMS Adaptive Equalizer for Nonstationary Wireless Channels In Mobile And AD HOC Networks. Personal, Indoor and Mobile Radio Communications”, 2002. The 13th IEEE International Symposium on. vol. 3, pp. 1131 – 1135, 2002.
[14]  J. Homer, “LMS estimation Via Structural Detection,” IEEE Trans. Signal Process. vol. 46, no.10, pp.  2651–2663, 1998.
[15]J. R. R. J. ,. P. B. M. L. Radek Martinek, "Least Mean Squares and Recursive Least Squares Algorithms for Total Harmonic Distortion Reduction Using Shunt Active Power Filter Control," MDPI, vol. 12, no. 1545, pp. 1-26, 2019.
[16]M. G.Mounika, "Convolutional Coded On-Off Keying Free-Space Optical Links over Fading Channels," International Journal of Engineering Trends and Technology (IJETT), vol. 4, no. 5, pp. 1-6, May 2013.
[17]S. S. M. M. N. O., Free Space Optical Communications: An Overview, vol. 12, 2016, p. 57.
[18] Lee, I.E.; Ghassemlooy, Z.; Ng, W.P.; Uysal, M., "Performance analysis of free space optical links over turbulence and misalignment induced fading channels," Communication Systems, Networks & Digital Signal Processing (CSNDSP), 2012 8th International Symposium on , vol., no., pp.1,6, 18-20 July 2012
[19]J. W. a. Z. P. Yi Weng, "Recent Advances in DSP Techniques for Mode Division Multiplexing Optical Networks with MIMO Equalization: A Review," MDPI, vol. 9, no. 6, pp. 1-28, 2019.
[20]  Toshihiko Komine, Jun Hwan Lee, Shinichiro Haruyama, and Masao Nakagawa, “Adaptive Equalization System for Visible Light Wireless Communication Utilizing Multiple White LED Lighting Equipment”, IEEE Trans. of Communications, vol. 8, no. 6, pp. 1-9, 2009
Menoufia Journal of Electronic Engineering Research
Volume 28, ICEEM2019-Special Issue
ICEEM2019-Special Issue: 1st International Conference on Electronic Eng., Faculty of Electronic Eng., Menouf, Egypt, 7-8 Dec.
2019
Pages 224-231

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