Performance Study of 1 Tbits/s WDM Coherent Optical OFDM System

Khaled Alatawi, Fahad Almasoudi, Mohammad A. Matin

Department of Electrical and Computer Engineering, University of Denver, Denver, USA.

DOI: 10.4236/opj.2013.35051                

Abstract

This paper investigates the architecture of Tbits/s Wavelength Division Multiplexing (WDM) system by using a Coherent Optical Orthogonal Frequency Division Multiplexing (CO-OFDM) with 4-QAM for long haul transmissions of 1800 Km SM. A simulation of 20 WDM channels spaced at 50 GHz, and 20 OFDM signals each with 50 Gbits/s bitrate to produce data rate of 1 Tbits/s is built. The system performance is studied by observing the constellation diagram of the signal and the relationship of BER and OSNR with regard to transmission distance. The results show that the BER increases as the transmission distance increases. Also, as the transmission distance increases, the OSNR needs to be increased to maintain BER in less than 10^-3.

Keywords

WDM; QAM; CO-OFDM; BER; OSNR

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	X. Yi, N. Fontaine, R. Scott and S. Yoo, “Tb/s Coherent Optical OFDM systems Enabled by Optical Frequency Combs,” Journal of Lightwave Technology, Vol. 28, No. 14, 2010, pp. 2054-2061. doi:10.1364/OE.16.000841
[2]	W. Shieh, H. Bao and Y. Tang, “Coherent Optical OFDM: Theory and Design,” Optics Express, Vol. 16, No. 2, 2008, pp. 841-859.
[3]	Z. Wang, X. Xie, J. Zhao, Z. Tong and X. Yang, “Performance Analysis of Different Modulation Schemes For Coherent Optical OFDM System,” 2010 International Conference on Communications and Mobile Computing (CMC), Shenzhen, 12-14 April 2010, pp. 23-25.
[4]	W. Shieh and I. Djordjevic, “OFDM for Optical COMMUNICATIONS,” Academic Press, Waltham, 2009.
[5]	I. Djordjevic, L. Xu and T. Wang, “Beyond 100 Gb∕s Optical Transmission Based on Polarization Multiplexed Coded-OFDM with Coherent Detection,” Journal of Optical Communications and Networking, IEEE/OSA, Vol. 1, No. 1, 2009, pp. 50-56.
[6]	B. Liu, X. Xin, L. Zhang and J. Yu,” 277.6-Gb/s LDPC-Coded CO-OFDM Transmission System with Low PAPR Based on Subcarrier Pre-Filtering Technology,” Optics Communications, Vol. 285, No. 24, 2012, pp. 5397-5400. doi:10.1016/j.optcom.2012.07.110
[7]	H. Wang, D. Kong, Y. Li, J. Wu and J. Lin, “Performance Evaluation of (D)APSK Modulated Coherent Optical OFDM System,” Optical Fiber Technology, Vol. 19, No. 3, 2013, pp. 242-249. doi:10.1016/j.yofte.2013.02.003
[8]	W. Shieh, X. Yi and Y. Tang, “Transmission Experiment of Multi-Gigabit Coherent Optical OFDM Systems over 1000 km SSMF Fibre,” Electronics Letters, Vol. 43, No. 3, 2007, pp. 183-184. doi:10.1049/el:20073496
[9]	Q. Yang, “High-Speed Coherent Optical Orthogonal Frequency-Division Multiplexing Design and Implementation,” Ph.D. Dissertation, The University of Melbourne, Melbourne, 2010.
[10]	X. Chen, “Theoretical and Experimental Study on High Spectral Efficiency Coherent Optical OFDM Systems,” Ph.D. Dissertation, The University of Melbourne, Melbourne, 2012.
[11]	J. Pan, “Nonlinear Electrical Compensation for the Coherent Optical OFDM System,” M.S. Thesis, Miami University, Oxford, 2010.
[12]	F. Almasoudi, K. Alatawi and M. Matin, “Study of OFDM Technique on RoF Passive Optical Network,” Optics and Photonics Journal, to be Published.
[13]	R. Fyath and M. Al-Qadi, “Investgation of I/Q Imbalance in Coherent Optical OFDM System,” World Academy of Science, Engineering and Technology, No. 60, 2011, pp. 1396-1401.
[14]	A. Lowery, D. Bangyuan and J. Armstrong, “Performance of Optical OFDM in Ultralong-Haul WDM Lightwave Systems,” Journal of Lightwave Technology, Vol. 25, No. 1, 2007, pp. 131-138. doi:10.1109/JLT.2006.888161
[15]	Z. Jian and A. Ellis, “Transmission of 4-ASK Optical Fast OFDM with Chromatic Dispersion Compensation,” Photonics Technology Letters, IEEE, Vol. 24, No. 1, 2012, pp. 34-36. doi:10.1109/LPT.2011.2171943
[16]	Y. Ma, Q. Yang, Y. Tang, S. Chen and W. Shieh, “1-Tb/s Single-Channel Coherent Optical OFDM Transmission over 600-km SSMF Fiber with Subwavelength Bandwidth Access,” Optics Express, Vol. 17, No. 11, 2009, pp. 9421-9427. doi:10.1364/OE.17.009421