Impact of frequency shift on nonlinear compensation using optical phase conjugation for M-QAM signals

and worst channels is also increased. For 50
transmission system in Figure 3. The transmission dis- Gbaud QPSK signal the Q-factor variation increases
tance is 800 km. Figures 10 and 11 shows Q factor of from 1.01 dB to 2.16 dB when the pump frequency
four channels at the receiver sides for 50 Gbaud QPSK increases from 193.05 THz to 192.8 THz (see Figure 10).
N. D. Binh et al.: Impact of Frequency Shift on Nonlinear Compensation using Optical Phase Conjugation 61
For 25 Gbaud 16-QAM signal, as seen in Figure 11 the san, S. K. Turitsyn, N. J. Doran, P. Harper, and A. D. Ellis,
Q-factor variation is 0.36 dB and 1.67 dB for pump “Exceeding the nonlinear-Shannon limit using Raman
frequency of 193.05 THz and 192.8 THz, respectively. laser based amplification and optical phase conjugation,”
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 P. Petropoulos, and D. J. Richardson, “Nonlinearity mit-
in Section 4.1 when considering the effectiveness of igation for multi-channel 64-QAM signals in a deployed
nonlinear compensation on factors such as symbol rate fiber link through optical phase conjugation,” in Proceed-
and modulation format order. ings of the Optical Fiber Communications Conference and
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 M. E. McCarthy, A. Perentos et al., “4 Tb/s transmission
We have presented the impact of frequency shift on reach enhancement using 10× 400 Gb/s super-channels
 and polarization insensitive dual band optical phase
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an OPC-based transmission systems using QPSK and S. Chandrasekhar, “Fiber nonlinearity mitigation of
16-QAM signals. The simulation results confirm the WDM-PDM QPSK/16-QAM signals using fiber-optic
 parametric amplifiers based multiple optical phase con-
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Acknowledgments 2014.
 [15] S. Namiki, K. Solis-Trapala, N. T. Hung, M. Pelusi, and
 T. Inoue, “Multi-channel cascadable parametric signal
This research is funded by Vietnam National Founda- processing for wavelength conversion and nonlinearity
tion for Science and Technology Development (NAFOS- compensation,” Journal of Lightwave Technology, vol. 35,
TED) under grant number 102.04-2016.36. no. 4, pp. 815–823, 2016.
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[22] W. Freude, R. Schmogrow, B. Nebendahl, M. Win- Nguyen Quang Nhu Quynh received the
 ter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, B.E. and M.E. degrees from The University of
 M. Dreschmann, M. Huebner et al., “Quality metrics for Danang - University of Science and Technol-
 optical signals: eye diagram, Q-factor, OSNR, EVM and ogy, Danang, Vietnam in 2002 and 2008, re-
 BER,” in Proceedings of the 14th International Conference on spectively. She received the Ph.D. degree from
 the University of Electro-Communications,
 Transparent Optical Networks (ICTON). IEEE, 2012, pp. Tokyo, Japan under Japanese Government
 1–4. (Monbukagakusho) Scholarship in 2016. Dr.
[23] P. J. Winzer and D. T. Neilson, “From scaling disparities Quynh is currently a lecturer/researcher in
 to integrated parallelism: A decathlon for a decade,” The University of Danang - University of Sci-
 Journal of Lightwave Technology, vol. 35, no. 5, pp. 1099– ence and Technology, Vietnam. Her research
 Nguyen Quang Nhu Quynh received the B.E. and M.E. degrees from The University of 
 Danang – University of Science and Technology, Danang, Vietnam in 2002 and 2008, 
 1115, 2017. respectively.interests She received includethe Ph.D. degree from high-speed the University of optical communications and all-optical
 Electro-Communications, Tokyo, Japan under Japanese Government 
 (Monbukagakusho)signal Scholarship processing in 2016. Dr. Quynh is currently technologies. a lecturer/researcher in 
[24] P. J. Winzer, “High-spectral-efficiency optical modulation The University of Danang - University of Science and Technology, Vietnam. Her 
 research interests include high-speed optical communications and all-optical signal 
 processing technologies. 
 formats,” Journal of Lightwave Technology, vol. 30, no. 24, 
 pp. 3824–3835, 2012. 
 5. Hồ Phước Tiến 
 Ho Phuoc Tien received the Engineer degree
1. Nguyen Duc Binh in 2004 from Ho Chi Minh City University
 Nguyen Duc Binh was born in 1984. He re- of Technology and the Master and Ph.D. de-
 ceived B.E. degree from Le Quy Don Technical grees, in 2006 and 2010 respectively, from
 University of Grenoble. Dr. Tien is now a lec-
 University, Viet Nam, in 2008, and M.E. degree
 in 2013 from Le Quy Don Technical Univer- turer/researcher at The Univeristy of Danang
 sity, Viet Nam. From 2013 to 2015, He has - University of Science and Technology. His
 worked as an operator and manager engineer research interests include signal processing,
 of optical transmission network at the High- image/video super resolution, visual atten-
 tech Communication Center, Communications tion and recognition.
 Command. He is currently a Ph.D. student 
 at Le Quy Don Technical University, Hanoi,
Nguyen Duc Binh was born in 1984. He received B.E. degree from Le QuyVietnam. Don 
Technical University, Viet Nam, in 2008, and M.E. degree in 2013 from Le Quy Don 
Technical University, Viet Nam. From 2013 to 2015, He has worked as an operator and 
manager engineer of optical transmission network at the Hightech Communication 
Center, Communications Command. He is currently a Ph.D student at Le Quy Don 
Technical University, Hanoi, Vietnam. 
 Nguyen Van Tuan was born in Danang, Viet-
 2. Nguyen Van Dien nam, in 1963. He received the B.E. degree from
 Nguyen Van Dien received the B.E. degree The University of Danang-University of Sci-
 from Ho Chi Minh City University of Tech- ence and Technology, Vietnam in 1985, and the
 nology and the Diplom-Ingenieur degree from M.E. and Ph.D. degrees from The Hanoi Uni-
 University of Stuttgart, Germanyin 2003 and versity of Science and Technology, Vietnam in
 2011, respectively. He is now a Ph.D. candi- 1998 and 2003, respectively. He worked as a
 date at The Univeristy of Danang - Univer- postdoctoral fellow at the Department of Elec-
 sity of Science and Technology. His research tronic and Communication, Sejong University,
 Korea. He is currently an Assosiate Professor
 interests includefiber-optics communications, 
 Nguyen Van Tuan was born in Danang, Vietnam, in 1963. He received the B.E.at degree The University of Danang-University of Sci-
 radio-over-fiber and microwave photonics for from The University of Danang-University of Science and Technology, Vietnam in 1985, 
 andence the M.E. and Ph.D. and degrees from Technology The Hanoi University of Science and whereTechnology, he works as the Dean of the Department
 next-generation access networks. Vietnam in 1998 and 2003, respectively. He worked as a postdoctoral fellow at the 
 DepartmentofElectronic of Electronic and Communication, and Sejong University, Telecommunication Korea. He is Engineering.
 currently an Assosiate Professor at The University of Danang-University of Science and 
Nguyen Van Dien received the B.E. degree from Ho Chi Minh City University of Technology where he works as the Dean of the Department of Electronic and 
Technology and the Diplom-Ingenieur degree from University of Stuttgart, Germanyin Telecommunication Engineering. 
2003 and 2011, respectively. He is now a Ph.D. candidate at The Univeristy of Danang - 
University of Science and Technology. His research interests includefiber-optics 
communications, radio-over-fiber and microwave photonics for next-generation access 
networks. 
 7. Nguyen Tan Hung 
3. Nguyen The Quang Nguyen Tan Hung
 Nguyen The Quang was born in 1978. He was born in Danang, Viet-
 received the B.E. degree from National De- nam, in 1980. He received the B.E. degree
 fense Academy, Japan, in 2004, the M.E. from The University of Danang-University of
 and Ph.D. degrees from the University of Science and Technology, Danang, Vietnam in
 Electro-Communications, Tokyo, Japanin 2009 2003, and the M.E. and Ph.D. degrees from the
 and 2012, respectively. From 2012 to 2014, University of Electro-Communications, Tokyo,
 he worked as a postdoctoral fellow at the Japan, in 2009 and 2012, respectively. From
 Department of Communication Engineering 2012 to 2016, he was a Researcher with the
 and Informatics, the University of Electro- National Institute of Advanced Industrial Sci-
 ence and Technology, Tsukuba, Japan, where
 Communications, Tokyo, Japan. He was a re- 
 Nguyen Tan Hung was born in Danang, Vietnam, in 1980. He received the B.E.he degree worked on ultrafast and spectrally efficient
 cipient of the Young Scientist Award at the from The University of Danang-University of Science and Technology, Danang, 
Nguyen The Quang was born in 1978. He received the B.E. degree from National Vietnamall-optical in 2003, and the M.E. networkand Ph.D. degrees from the technologies, University of and development of an all-optical
Defense Academy, Japan, in 2004, the M.E. and Ph.D. degrees from the University of 
15th OptoElectronics and Communications Conference (OECC 2010) Electro-Communications, Tokyo, Japan, in 2009 and 2012, respectively. From 2012 to 
 2016,wavelength he was a Researcher with the National converter. Institute of Advanced Industrial HeScience is currently a Teacher in the Department
presented by the IEEE Photonics Society Japan Chapter. His research and Technology, Tsukuba, Japan, where he worked on ultrafast and spectrally efficient 
 all-optical network technologies, and development of an all-optical wavelength 
interest is all-optical signal processing based on nonlinear fiber optics of Electronic and Telecommunication Engineering, The University of
for WDM and OTDM systems. He is currently a Lecturer at Le Quy Danang-University of Science and Technology, Danang, Vietnam. His
Don Technical University, Hanoi, Vietnam. research interests include optical communications and networking,
 all-optical signal processing and photonic integrated circuits.