Abstract

Non-return-to-zero (NRZ), carrier-suppressed return-to-zero (CSRZ), and 33% return-to-zero (RZ) are the three most commonly used modulation formats in the current fiber-optical communication system. In this paper, we investigate and comprehensively compare their performance using the recently proposed receiver side duobinary shaping Nyquist wavelength division multiplexing (RS-DBS Nyquist WDM) technique, which is believed to be one of the promising candidates in the next high-capacity, high-data-rate, long-distance optical transmission systems with its cost-effective capability. It is found that, in a scenario of 3×112Gbps polarization division multiplexing quadrature phase-shift keying (PDM-QPSK) RS-DBS Nyquist WDM transmission, for back-to-back (B2B) transmission, NRZ can obtain almost the same performance as CSRZ and 33% RZ at the optimum bandwidth of 0.82× symbol rate for optical filters at the transmitter side. However, under narrower bandwidth optical filtering, CSRZ and 33% RZ signals have advantages over NRZ signal for requiring 0.5 and 1 dB less optical signal-to-noise ratio at BER=1×103 with a 0.6× symbol rate bandwidth optical filter. Moreover, using the optimum optical filter, after a 1600 km single-mode fiber (SMF) transmission, the CSRZ and 33% RZ signals can achieve 0.55 and 0.7 dB Q factor improvements over NRZ signals, by taking fiber nonlinearity into account. The RZ format is more ideal for the RS-DBS Nyquist WDM system with long-haul SMF transmissions.

© 2014 Optical Society of America

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  1. K. Ennser and K. Petermann, “Performance of RZ versus NRZ-transmission on standard single-mode fibers,” IEEE Photon. Technol. Lett., vol.  8, no. 3, pp. 443–445, Mar. 1996.
    [CrossRef]
  2. B. Bakhshi, M. Vaa, E. A. Golovchenko, W. W. Patterson, R. L. Maybach, and N. S. Bergano, “Comparison of CRZ, RZ and NRZ modulation formats in a 65 × 12.3 Gb/s WDM transmission experiment over 9000 km,” in Proc. OFC, 2001, paper WF4.
  3. P. Winzer, H. Kogelnik, C. H. Kim, H. Kim, R. M. Jopson, and L. E. Nelson, “Effect of receiver design on PMD outage for RZ and NRZ,” in Proc. OFC, 2002, paper TuI1.
  4. H. S. Lin and P. C. Lai, “Single Mach-Zehnder modulator with RZ-DPSK modulation signal in 48 Chs × 40 Gbit/s long haul DWDM transmission,” J. Opt. Commun., vol.  34, no. 3, pp. 155–160, 2013.
    [CrossRef]
  5. J. X. Cai, Y. Cai, C. R. Davidson, D. G. Foursa, A. J. Lucero, O. V. Sinkin, W. W. Patterson, A. N. Pilipetskii, G. Mohs, and N. S. Bergano, “Transmission of 96 × 100 Gb/s bandwidth-constrained PDM-RZ-QPSK channels with 300% spectral efficiency over 10610 km and 400% spectral efficiency over 4370 km,” J. Lightwave Technol., vol.  29, no. 4, pp. 491–498, 2011.
    [CrossRef]
  6. W. Jia, Y. Matsui, D. Mahgerefteh, I. Lyubomirsky, and C. K. Chan, “Generation and transmission of 10-Gbaud optical 3/4-RZ-DQPSK signals using a chirp-managed DBR laser,” J. Lightwave Technol., vol.  30, no. 21, pp. 3299–3305, 2012.
    [CrossRef]
  7. X. Zhou, L. E. Nelson, R. Isaac, B. Zhu, D. W. Peckham, P. I. Borel, and K. Carlson, “PDM-Nyquist-32QAM for 450 Gb/s per-channel WDM transmission on the 50 GHz ITU-T grid,” J. Lightwave Technol., vol.  30, no. 4, pp. 553–559, Feb. 2012.
    [CrossRef]
  8. C. R. S. Fludger, “Coherent equalization and POLMUX-RZ-DQPSK for robust 100-GE transmission,” J. Lightwave Technol., vol.  26, no. 1, pp. 64–72, 2008.
    [CrossRef]
  9. H. Takahashi, A. A. Amin, S. L. Jansen, I. Morita, and H. Tanaka, “Highly spectrally efficient DWDM transmission at 7.0 b/s/Hz using 8 × 65.1 Gb/s coherent PDM-OFDM,” J. Lightwave Technol., vol.  28, no. 4, pp. 406–414, Feb. 2010.
    [CrossRef]
  10. J. Li, E. Tipsuwannakul, T. Eriksson, M. Karlsson, and P. A. Andrekson, “Approaching Nyquist limit in WDM systems by low-complexity receiver-side duobinary shaping,” J. Lightwave Technol., vol.  30, no. 11, pp. 1664–1676, 2012.
    [CrossRef]
  11. J. Li, M. Sjödin, M. Karlsson, and P. A. Andrekson, “Building up low-complexity spectrally-efficient terabit superchannels by receiver-side duobinary shaping,” Opt. Express, vol.  20, no. 9, pp. 10271–10282, 2012.
    [CrossRef]
  12. J. Yu, Z. Dong, H. C. Chien, Z. Jia, X. Li, D. Huo, M. Gunkel, P. Wagner, H. Mayer, and A. Schippel, “Transmission of 200 G PDM-CSRZ-QPSK and PDM-16 QAM with a SE of 4 b/s/Hz,” J. Lightwave Technol., vol.  31, no. 4, pp. 515–522, 2013.
    [CrossRef]
  13. J. Zhang, B. Huang, and X. Li, “Improved quadrature duobinary system performance using multi-modulus equalization,” IEEE Photon. Technol. Lett, vol.  25, no. 16, pp. 1630–1633, 2013.
    [CrossRef]
  14. J. Yu, J. Zhang, Z. Dong, Z. Jia, H. Chien, Y. Cai, X. Xiao, and X. Li, “Transmission of 8 × 480 Gb/s super-Nyquist-filtering 9-QAM-like signal at 100 GHz-grid over 5000 km SMF-28 and twenty-five 100 GHz-grid ROADMs,” Opt. Express, vol.  21, no. 13, pp. 15686–15691 (2013).
    [CrossRef]
  15. J. Zhang, J. Yu, N. Chi, Z. Dong, J. Yu, X. Li, L. Tao, and Y. Shao, “Multi-modulus blind equalizations for coherent quadrature duobinary spectrum shaped PM-QPSK digital signal processing,” J. Lightwave Technol., vol.  31, no. 7, pp. 1073–1078, 2013.
    [CrossRef]
  16. J. Li, M. Karlsson, P. A. Andrekson, and K. Xu, “Transmission of 1.936 Tb/s (11 × 176 Gb/s) DP-16QAM superchannel signals over 640 km SSMF with EDFA only and 300 GHz WSS channel,” Opt. Express, vol.  20, no. 26, pp. B223–B231, 2012.
    [CrossRef]
  17. M. I. Hayee and A. E. Willner, “NRZ versus RZ in 10–40 Gb/s dispersion-managed WDM transmission systems,” IEEE Photon. Technol. Lett., vol.  11, no. 8, pp. 991–993, 1999.
    [CrossRef]
  18. F. Heismann, “System requirements for WSS filter shape in cascaded ROADM networks,” in Proc. OFC, 2010, paper OThR1.
  19. I. Fatadin, S. J. Savory, and D. Ives, “Compensation of quadrature imbalance in an optical QPSK coherent receiver,” IEEE Photon. Technol. Lett., vol.  20, no. 20, pp. 1733–1735, 2008.
    [CrossRef]
  20. M. Selmi, Y. Jaouen, and P. Ciblat, “Accurate digital frequency offset estimator for coherent PolMux QAM transmission systems,” presented at the European Conf. Optical Communication, Vienna, Austria, Sept. 2009, paper P3.08.
  21. A. J. Viterbi and A. M. Viterbi, “Nonlinear estimation of PSK-modulated carrier phase with application to burst digital transmission,” IEEE Trans. Inf. Theory, vol.  29, no. 4, pp. 543–551, July 1983.
    [CrossRef]

2013 (5)

2012 (5)

2011 (1)

2010 (1)

2008 (2)

C. R. S. Fludger, “Coherent equalization and POLMUX-RZ-DQPSK for robust 100-GE transmission,” J. Lightwave Technol., vol.  26, no. 1, pp. 64–72, 2008.
[CrossRef]

I. Fatadin, S. J. Savory, and D. Ives, “Compensation of quadrature imbalance in an optical QPSK coherent receiver,” IEEE Photon. Technol. Lett., vol.  20, no. 20, pp. 1733–1735, 2008.
[CrossRef]

1999 (1)

M. I. Hayee and A. E. Willner, “NRZ versus RZ in 10–40 Gb/s dispersion-managed WDM transmission systems,” IEEE Photon. Technol. Lett., vol.  11, no. 8, pp. 991–993, 1999.
[CrossRef]

1996 (1)

K. Ennser and K. Petermann, “Performance of RZ versus NRZ-transmission on standard single-mode fibers,” IEEE Photon. Technol. Lett., vol.  8, no. 3, pp. 443–445, Mar. 1996.
[CrossRef]

1983 (1)

A. J. Viterbi and A. M. Viterbi, “Nonlinear estimation of PSK-modulated carrier phase with application to burst digital transmission,” IEEE Trans. Inf. Theory, vol.  29, no. 4, pp. 543–551, July 1983.
[CrossRef]

Amin, A. A.

Andrekson, P. A.

Bakhshi, B.

B. Bakhshi, M. Vaa, E. A. Golovchenko, W. W. Patterson, R. L. Maybach, and N. S. Bergano, “Comparison of CRZ, RZ and NRZ modulation formats in a 65 × 12.3 Gb/s WDM transmission experiment over 9000 km,” in Proc. OFC, 2001, paper WF4.

Bergano, N. S.

Borel, P. I.

Cai, J. X.

Cai, Y.

Carlson, K.

Chan, C. K.

Chi, N.

Chien, H.

Chien, H. C.

Ciblat, P.

M. Selmi, Y. Jaouen, and P. Ciblat, “Accurate digital frequency offset estimator for coherent PolMux QAM transmission systems,” presented at the European Conf. Optical Communication, Vienna, Austria, Sept. 2009, paper P3.08.

Davidson, C. R.

Dong, Z.

Ennser, K.

K. Ennser and K. Petermann, “Performance of RZ versus NRZ-transmission on standard single-mode fibers,” IEEE Photon. Technol. Lett., vol.  8, no. 3, pp. 443–445, Mar. 1996.
[CrossRef]

Eriksson, T.

Fatadin, I.

I. Fatadin, S. J. Savory, and D. Ives, “Compensation of quadrature imbalance in an optical QPSK coherent receiver,” IEEE Photon. Technol. Lett., vol.  20, no. 20, pp. 1733–1735, 2008.
[CrossRef]

Fludger, C. R. S.

Foursa, D. G.

Golovchenko, E. A.

B. Bakhshi, M. Vaa, E. A. Golovchenko, W. W. Patterson, R. L. Maybach, and N. S. Bergano, “Comparison of CRZ, RZ and NRZ modulation formats in a 65 × 12.3 Gb/s WDM transmission experiment over 9000 km,” in Proc. OFC, 2001, paper WF4.

Gunkel, M.

Hayee, M. I.

M. I. Hayee and A. E. Willner, “NRZ versus RZ in 10–40 Gb/s dispersion-managed WDM transmission systems,” IEEE Photon. Technol. Lett., vol.  11, no. 8, pp. 991–993, 1999.
[CrossRef]

Heismann, F.

F. Heismann, “System requirements for WSS filter shape in cascaded ROADM networks,” in Proc. OFC, 2010, paper OThR1.

Huang, B.

J. Zhang, B. Huang, and X. Li, “Improved quadrature duobinary system performance using multi-modulus equalization,” IEEE Photon. Technol. Lett, vol.  25, no. 16, pp. 1630–1633, 2013.
[CrossRef]

Huo, D.

Isaac, R.

Ives, D.

I. Fatadin, S. J. Savory, and D. Ives, “Compensation of quadrature imbalance in an optical QPSK coherent receiver,” IEEE Photon. Technol. Lett., vol.  20, no. 20, pp. 1733–1735, 2008.
[CrossRef]

Jansen, S. L.

Jaouen, Y.

M. Selmi, Y. Jaouen, and P. Ciblat, “Accurate digital frequency offset estimator for coherent PolMux QAM transmission systems,” presented at the European Conf. Optical Communication, Vienna, Austria, Sept. 2009, paper P3.08.

Jia, W.

Jia, Z.

Jopson, R. M.

P. Winzer, H. Kogelnik, C. H. Kim, H. Kim, R. M. Jopson, and L. E. Nelson, “Effect of receiver design on PMD outage for RZ and NRZ,” in Proc. OFC, 2002, paper TuI1.

Karlsson, M.

Kim, C. H.

P. Winzer, H. Kogelnik, C. H. Kim, H. Kim, R. M. Jopson, and L. E. Nelson, “Effect of receiver design on PMD outage for RZ and NRZ,” in Proc. OFC, 2002, paper TuI1.

Kim, H.

P. Winzer, H. Kogelnik, C. H. Kim, H. Kim, R. M. Jopson, and L. E. Nelson, “Effect of receiver design on PMD outage for RZ and NRZ,” in Proc. OFC, 2002, paper TuI1.

Kogelnik, H.

P. Winzer, H. Kogelnik, C. H. Kim, H. Kim, R. M. Jopson, and L. E. Nelson, “Effect of receiver design on PMD outage for RZ and NRZ,” in Proc. OFC, 2002, paper TuI1.

Lai, P. C.

H. S. Lin and P. C. Lai, “Single Mach-Zehnder modulator with RZ-DPSK modulation signal in 48 Chs × 40 Gbit/s long haul DWDM transmission,” J. Opt. Commun., vol.  34, no. 3, pp. 155–160, 2013.
[CrossRef]

Li, J.

Li, X.

Lin, H. S.

H. S. Lin and P. C. Lai, “Single Mach-Zehnder modulator with RZ-DPSK modulation signal in 48 Chs × 40 Gbit/s long haul DWDM transmission,” J. Opt. Commun., vol.  34, no. 3, pp. 155–160, 2013.
[CrossRef]

Lucero, A. J.

Lyubomirsky, I.

Mahgerefteh, D.

Matsui, Y.

Maybach, R. L.

B. Bakhshi, M. Vaa, E. A. Golovchenko, W. W. Patterson, R. L. Maybach, and N. S. Bergano, “Comparison of CRZ, RZ and NRZ modulation formats in a 65 × 12.3 Gb/s WDM transmission experiment over 9000 km,” in Proc. OFC, 2001, paper WF4.

Mayer, H.

Mohs, G.

Morita, I.

Nelson, L. E.

X. Zhou, L. E. Nelson, R. Isaac, B. Zhu, D. W. Peckham, P. I. Borel, and K. Carlson, “PDM-Nyquist-32QAM for 450 Gb/s per-channel WDM transmission on the 50 GHz ITU-T grid,” J. Lightwave Technol., vol.  30, no. 4, pp. 553–559, Feb. 2012.
[CrossRef]

P. Winzer, H. Kogelnik, C. H. Kim, H. Kim, R. M. Jopson, and L. E. Nelson, “Effect of receiver design on PMD outage for RZ and NRZ,” in Proc. OFC, 2002, paper TuI1.

Patterson, W. W.

Peckham, D. W.

Petermann, K.

K. Ennser and K. Petermann, “Performance of RZ versus NRZ-transmission on standard single-mode fibers,” IEEE Photon. Technol. Lett., vol.  8, no. 3, pp. 443–445, Mar. 1996.
[CrossRef]

Pilipetskii, A. N.

Savory, S. J.

I. Fatadin, S. J. Savory, and D. Ives, “Compensation of quadrature imbalance in an optical QPSK coherent receiver,” IEEE Photon. Technol. Lett., vol.  20, no. 20, pp. 1733–1735, 2008.
[CrossRef]

Schippel, A.

Selmi, M.

M. Selmi, Y. Jaouen, and P. Ciblat, “Accurate digital frequency offset estimator for coherent PolMux QAM transmission systems,” presented at the European Conf. Optical Communication, Vienna, Austria, Sept. 2009, paper P3.08.

Shao, Y.

Sinkin, O. V.

Sjödin, M.

Takahashi, H.

Tanaka, H.

Tao, L.

Tipsuwannakul, E.

Vaa, M.

B. Bakhshi, M. Vaa, E. A. Golovchenko, W. W. Patterson, R. L. Maybach, and N. S. Bergano, “Comparison of CRZ, RZ and NRZ modulation formats in a 65 × 12.3 Gb/s WDM transmission experiment over 9000 km,” in Proc. OFC, 2001, paper WF4.

Viterbi, A. J.

A. J. Viterbi and A. M. Viterbi, “Nonlinear estimation of PSK-modulated carrier phase with application to burst digital transmission,” IEEE Trans. Inf. Theory, vol.  29, no. 4, pp. 543–551, July 1983.
[CrossRef]

Viterbi, A. M.

A. J. Viterbi and A. M. Viterbi, “Nonlinear estimation of PSK-modulated carrier phase with application to burst digital transmission,” IEEE Trans. Inf. Theory, vol.  29, no. 4, pp. 543–551, July 1983.
[CrossRef]

Wagner, P.

Willner, A. E.

M. I. Hayee and A. E. Willner, “NRZ versus RZ in 10–40 Gb/s dispersion-managed WDM transmission systems,” IEEE Photon. Technol. Lett., vol.  11, no. 8, pp. 991–993, 1999.
[CrossRef]

Winzer, P.

P. Winzer, H. Kogelnik, C. H. Kim, H. Kim, R. M. Jopson, and L. E. Nelson, “Effect of receiver design on PMD outage for RZ and NRZ,” in Proc. OFC, 2002, paper TuI1.

Xiao, X.

Xu, K.

Yu, J.

Zhang, J.

Zhou, X.

Zhu, B.

IEEE Photon. Technol. Lett (1)

J. Zhang, B. Huang, and X. Li, “Improved quadrature duobinary system performance using multi-modulus equalization,” IEEE Photon. Technol. Lett, vol.  25, no. 16, pp. 1630–1633, 2013.
[CrossRef]

IEEE Photon. Technol. Lett. (3)

M. I. Hayee and A. E. Willner, “NRZ versus RZ in 10–40 Gb/s dispersion-managed WDM transmission systems,” IEEE Photon. Technol. Lett., vol.  11, no. 8, pp. 991–993, 1999.
[CrossRef]

I. Fatadin, S. J. Savory, and D. Ives, “Compensation of quadrature imbalance in an optical QPSK coherent receiver,” IEEE Photon. Technol. Lett., vol.  20, no. 20, pp. 1733–1735, 2008.
[CrossRef]

K. Ennser and K. Petermann, “Performance of RZ versus NRZ-transmission on standard single-mode fibers,” IEEE Photon. Technol. Lett., vol.  8, no. 3, pp. 443–445, Mar. 1996.
[CrossRef]

IEEE Trans. Inf. Theory (1)

A. J. Viterbi and A. M. Viterbi, “Nonlinear estimation of PSK-modulated carrier phase with application to burst digital transmission,” IEEE Trans. Inf. Theory, vol.  29, no. 4, pp. 543–551, July 1983.
[CrossRef]

J. Lightwave Technol. (8)

J. Yu, Z. Dong, H. C. Chien, Z. Jia, X. Li, D. Huo, M. Gunkel, P. Wagner, H. Mayer, and A. Schippel, “Transmission of 200 G PDM-CSRZ-QPSK and PDM-16 QAM with a SE of 4 b/s/Hz,” J. Lightwave Technol., vol.  31, no. 4, pp. 515–522, 2013.
[CrossRef]

J. X. Cai, Y. Cai, C. R. Davidson, D. G. Foursa, A. J. Lucero, O. V. Sinkin, W. W. Patterson, A. N. Pilipetskii, G. Mohs, and N. S. Bergano, “Transmission of 96 × 100 Gb/s bandwidth-constrained PDM-RZ-QPSK channels with 300% spectral efficiency over 10610 km and 400% spectral efficiency over 4370 km,” J. Lightwave Technol., vol.  29, no. 4, pp. 491–498, 2011.
[CrossRef]

W. Jia, Y. Matsui, D. Mahgerefteh, I. Lyubomirsky, and C. K. Chan, “Generation and transmission of 10-Gbaud optical 3/4-RZ-DQPSK signals using a chirp-managed DBR laser,” J. Lightwave Technol., vol.  30, no. 21, pp. 3299–3305, 2012.
[CrossRef]

X. Zhou, L. E. Nelson, R. Isaac, B. Zhu, D. W. Peckham, P. I. Borel, and K. Carlson, “PDM-Nyquist-32QAM for 450 Gb/s per-channel WDM transmission on the 50 GHz ITU-T grid,” J. Lightwave Technol., vol.  30, no. 4, pp. 553–559, Feb. 2012.
[CrossRef]

C. R. S. Fludger, “Coherent equalization and POLMUX-RZ-DQPSK for robust 100-GE transmission,” J. Lightwave Technol., vol.  26, no. 1, pp. 64–72, 2008.
[CrossRef]

H. Takahashi, A. A. Amin, S. L. Jansen, I. Morita, and H. Tanaka, “Highly spectrally efficient DWDM transmission at 7.0 b/s/Hz using 8 × 65.1 Gb/s coherent PDM-OFDM,” J. Lightwave Technol., vol.  28, no. 4, pp. 406–414, Feb. 2010.
[CrossRef]

J. Li, E. Tipsuwannakul, T. Eriksson, M. Karlsson, and P. A. Andrekson, “Approaching Nyquist limit in WDM systems by low-complexity receiver-side duobinary shaping,” J. Lightwave Technol., vol.  30, no. 11, pp. 1664–1676, 2012.
[CrossRef]

J. Zhang, J. Yu, N. Chi, Z. Dong, J. Yu, X. Li, L. Tao, and Y. Shao, “Multi-modulus blind equalizations for coherent quadrature duobinary spectrum shaped PM-QPSK digital signal processing,” J. Lightwave Technol., vol.  31, no. 7, pp. 1073–1078, 2013.
[CrossRef]

J. Opt. Commun. (1)

H. S. Lin and P. C. Lai, “Single Mach-Zehnder modulator with RZ-DPSK modulation signal in 48 Chs × 40 Gbit/s long haul DWDM transmission,” J. Opt. Commun., vol.  34, no. 3, pp. 155–160, 2013.
[CrossRef]

Opt. Express (3)

Other (4)

M. Selmi, Y. Jaouen, and P. Ciblat, “Accurate digital frequency offset estimator for coherent PolMux QAM transmission systems,” presented at the European Conf. Optical Communication, Vienna, Austria, Sept. 2009, paper P3.08.

F. Heismann, “System requirements for WSS filter shape in cascaded ROADM networks,” in Proc. OFC, 2010, paper OThR1.

B. Bakhshi, M. Vaa, E. A. Golovchenko, W. W. Patterson, R. L. Maybach, and N. S. Bergano, “Comparison of CRZ, RZ and NRZ modulation formats in a 65 × 12.3 Gb/s WDM transmission experiment over 9000 km,” in Proc. OFC, 2001, paper WF4.

P. Winzer, H. Kogelnik, C. H. Kim, H. Kim, R. M. Jopson, and L. E. Nelson, “Effect of receiver design on PMD outage for RZ and NRZ,” in Proc. OFC, 2002, paper TuI1.

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Figures (7)

Fig. 1.
Fig. 1.

(a) 3×112Gbps PDM-QPSK Nyquist WDM system setup and digital signal processing flow. (b) Generation of 112 Gbps PDM-QPSK RZ signals using a pulse carver in the transmitter side.

Fig. 2.
Fig. 2.

Contour plot of Q factor as a function of bandwidths of the optical filters at the transmitter side and the receiver side for (a) single channel using conventional DSP, (b) central channel in three-channel WDM using conventional DSP, and (c) central channel in three-channel WDM using conventional DSP and post-filter together with MLSD. BOTx and BORx represent the bandwidths of the optical filters at the transmitter side and receiver side, respectively. R equals the symbol rate.

Fig. 3.
Fig. 3.

(a) Spectral envelope of a 112 Gbps PDM-QPSK single carrier with different modulation formats and the spectra of an ideal fourth Gaussian filter with 23 GHz bandwidth. (b) Spectral envelope of a 112 Gbps PDM-QPSK single carrier filtered by a 23 GHz fourth Gaussian filter.

Fig. 4.
Fig. 4.

Inverse frequency response of a CMA equalizer for different modulation formats and an ideal duobinary filter in 3×112Gbps PDM-QPSK WDM systems. BOTx=23GHz, OSNR=17dB.

Fig. 5.
Fig. 5.

BER as a function of OSNR for three modulation formats in 3×112Gbps PDM-QPSK B2B transmission.

Fig. 6.
Fig. 6.

Contour plot of Q factor as a function of optic filter bandwidth and Alpha coefficient under condition of OSNR=17dB.

Fig. 7.
Fig. 7.

Calculated Q factor in variance of launched power for 3×112Gbps PDM-QPSK WDM system after 1600 km SMF transmission.