Türbülans Altında Serbest Alan Optik Haberleşmede SNR Araştırması

Yıl 2018, Cilt: 8 Sayı: 2, 438 - 445, 01.06.2018

Pelin Demir Güneş Yılmaz

Öz

Atmosferik türbülans, serbest alan optik iletişim sistemlerinde önemli bir zayıflatma etkisidir. Türbülans, dikey mesafe, sıcaklık, basınç ve rüzgar hızına göre değişmektedir. Bu çalışmada üç farklı dalga boyunda 1064nm, 976nm ve 850nm ve türbülans altında SNR değerleri 10 km yüksekliğe kadar analiz edilmiştir. Analiz sonucunda yükseklik ve türbülans değerlerine göre SNR değerleri karşılaştırılmıştır

Anahtar Kelimeler

Serbest uzay optik, Türbülans, Sinyal gürültü oranı

The Investigation of SNR for Free Space Optical Communication Under Turbulence

Öz

Atmospheric turbulence is a significant attenuation effect in free-space optical communication systems. The turbulence varies according to the vertical distance, temperature, pressure and wind speed. In this study, SNR values with three different wavelengths and turbulence strength were analyzed up to 10 km altitude. As a result of the analysis, the SNR values were compared according to height and turbulence values.

Anahtar Kelimeler

Free space optic, Turbulence, Signal to noise ratio

Kaynakça

• Bufton, JL., Minott P., Fitzmaurice, MW., Titterton, PJ. 1972. Measurements of turbulence profiles in the troposphere, J. Optic Soci. America, 62(9): 1068-1070.
• Cao, J., Zhao X., Liu W., Gu H. 2017. Performance analysis of a coherent free space optical communication system based on experiment Opt Exp, 25(13):15299- 15312
• Chan, VWS. 2006. Free-Space Optical Communications J. Light Tech., 24(12): 4750-4762.
• Cherian, J. M., Chacko, S.C., Kavitha, B.C., Sunilkumar, K. 2015. Atmospheric turbulence and pointing errors effects in the performance matrices of wireless optical links. Int. J. Electr. Comm. Comp. Tech., 5(2): 831-833.
• El-Wakeel, AS., Mohammed, NIA., Aly, MH. 2016. Free space optical communications system performance under atmospheric scattering and turbulence for 850 and 1550 nm operation. App. Optics, 55(26): 7276- 7286.
• Guoliang, X., Xuping, Z., Junwei, W., Xiaoyong, F. 2004. Influence of atmospheric turbulence on FSO link performance. Opt. Trans. Switc., Subs. Proc. SPIE, 5281:816-823.
• Kvíčala, R., Kvičera, V., Grábner, M., Fišer, O. 2007. BER and availability measured on FSO link. Radio Eng., 16(3):7-12.
• Li S., Xu Z., Liu J., Zhou N., Zhao Y., Zhu L., Xia F., Wang J. 2015. Experimental Demonstration of Free-Space Optical Communications Using Orbital Angular Momentum (OAM) Array Encoding/Decoding. Las Elec-Opt (CLEO).
• Mahdieh, MH., Pournoury, M. 2010. Atmospheric turbulence and numerical evaluation of bit error rate (BER) in free-space communication. Opt. Las Tech., 42(1): 55-60.
• Majumdar, AK., Ricklin, JC. 2008. Free-Space Laser Communications Principles and Advances, Springer, USA, New York.
• Majumdar, AK. 2015. Advanced Free Space Optics (FSO) A Systems Approach, Springer, USA, New York.
• Motlagh, C., Ahmadi, V., Ghassemlooy, Z., Abedi, K. 2008. The Effect of atmospheric turbulence on the performance of the free space optical communications, 6th Int. Sym. on Com. Sys., Net. and Dig. Sig. Proc. 540–543.
• Navidpour, SM., Uysal, M., Kavehrad, M. 2007. BER performance of free-space optical transmission with spatial diversity. IEEE Transc on Wire Comm., 6(8): 2813- 2819.
• Odeyemi, KO., Owolawi, PA., Srivastava, VM. 2017. Performance analysis of free space optical system with spatial modulation and diversity combiners over the Gamma Gamma atmospheric turbulence. Opt. Comm., 382(1): 205–211.
• Parenti, RR., Roth, JM., Shapiro, JH., Walther FG., Greco, JA. 2012. Experimental observations of channel reciprocity in single-mode free-space optical links. Opt. Exp., 20(19): 21635- 21644.
• Plank, T., Leitgeb, E., Pezzei P., Ghassemlooy, Z. 2012. Wavelength selection for high data rate free space optics (FSO) in next generation wireless communication, 17th Euro. Conf. on Net. and Opt. Com., 1-5.
• Saha, SK. 2011. Aperture Synthesis Methods and Applications to Optical Astronomy, Springer, USA, New York.
• Shah, D., Nayak, B., Jethawani, D. 2014. Study of different atmospheric channel models. Int. J. Elect. Com. Eng. Tech. (IJECET), 5(1):105-112.
• Singh, P., Singh ML. 2014. Experimental determination and comparison of rain attenuation in free space optic link operating at 532 nm and 655 nm wavelength. Optik, 125: 4599–4602
• Strömgren, T. 2008. Modelling of turbulent gas-particle flow. Technical Reports Royal Institute of Technology Department of Mechanics.
• Talay, TA. 2006. Introduction To The Aerodynamics Of Flight. Sci Tech Inf Off Nati Aero and Spa Admin (NASA), 7.
• Tóth J., Tatarko M., Ovseník D., Turán J. 2015. Long Term Availability Analysis of Experimental Free Space Optics System Systems. Int. Sig. Im. Proc. (IWSSIP), 29-32.
• Yuksel, H. 2005. Studies of the effects of atmospheric turbulence on free space optical communications. Doctor of philosophy thesis, University of Maryland, 127 s.