Abstract

In this paper, we propose a low-complexity format-transparent digital signal processing (DSP) scheme for next generation flexible and energy-efficient transceiver. It employs QPSK symbols as the training and pilot symbols for the initialization and tracking stage of the receiver-side DSP, respectively, for various modulation formats. The performance is numerically and experimentally evaluated in a dual polarization (DP) 11 Gbaud 64QAM system. Employing the proposed DSP scheme, we conduct a system-level study of Tb/s bandwidth-adaptive superchannel transmissions with flexible modulation formats including QPSK, 8QAM and 16QAM. The spectrum bandwidth allocation is realized in the digital domain instead of turning on/off sub-channels, which improves the performance of higher order QAM. Various transmission distances ranging from 240 km to 6240 km are demonstrated with a colorless detection for hardware complexity reduction.

© 2014 Optical Society of America

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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
  8. M. Kuschnerov, M. Chouayakh, K. Piyawanno, B. Spinnler, E. de Man, P. Kainzmaier, M. S. Alfiad, A. Napoli, B. Lankl, “Data-aided versus blind single-carrier coherent receivers,” IEEE Photonics Journal 2(3), 387–403 (2010).
    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
  18. P. Poggiolini, G. Bosco, A. Carena, V. Curri, V. Miot, F. Forghieri, “Performance Dependence on Channel Baud-Rate of PM-QPSK Systems Over Uncompensated Links,” IEEE Photon. Technol. Lett. 23(1), 15–17 (2011).
    [CrossRef]
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    [CrossRef]

2013 (2)

M. Morsy-Osman, M. Chagnon, X. Xu, Q. Zhuge, M. Poulin, Y. Painchaud, M. Pelletier, C. Paquet, D. V. Plant, “Colorless and preamplifierless reception using an integrated Si-photonic coherent receiver,” IEEE Photon. Technol. Lett. 25(11), 1027–1030 (2013).
[CrossRef]

Q. Zhuge, M. Morsy-Osman, X. Xu, M. Chagnon, M. Qiu, D. V. Plant, “Spectral efficiency-adaptive optical transmission using time domain hybrid QAM for agile optical networks,” J. Lightwave Technol. 31(15), 2621–2628 (2013).
[CrossRef]

2012 (5)

2011 (3)

2010 (2)

K. Roberts, D. Beckett, D. Boertjes, J. Berthold, C. Laperle, “100G and beyond with digital coherent signal processing,” IEEE Commun. Mag. 48(7), 62–69 (2010).
[CrossRef]

M. Kuschnerov, M. Chouayakh, K. Piyawanno, B. Spinnler, E. de Man, P. Kainzmaier, M. S. Alfiad, A. Napoli, B. Lankl, “Data-aided versus blind single-carrier coherent receivers,” IEEE Photonics Journal 2(3), 387–403 (2010).
[CrossRef]

2009 (2)

1988 (1)

M. Oerder, H. Meyr, “Digital filter and square timing recovery,” IEEE Trans. Commun. 36(5), 605–612 (1988).
[CrossRef]

Alfiad, M. S.

M. Kuschnerov, M. Chouayakh, K. Piyawanno, B. Spinnler, E. de Man, P. Kainzmaier, M. S. Alfiad, A. Napoli, B. Lankl, “Data-aided versus blind single-carrier coherent receivers,” IEEE Photonics Journal 2(3), 387–403 (2010).
[CrossRef]

Beckett, D.

K. Roberts, D. Beckett, D. Boertjes, J. Berthold, C. Laperle, “100G and beyond with digital coherent signal processing,” IEEE Commun. Mag. 48(7), 62–69 (2010).
[CrossRef]

Berthold, J.

K. Roberts, D. Beckett, D. Boertjes, J. Berthold, C. Laperle, “100G and beyond with digital coherent signal processing,” IEEE Commun. Mag. 48(7), 62–69 (2010).
[CrossRef]

Boertjes, D.

K. Roberts, D. Beckett, D. Boertjes, J. Berthold, C. Laperle, “100G and beyond with digital coherent signal processing,” IEEE Commun. Mag. 48(7), 62–69 (2010).
[CrossRef]

Bosco, G.

G. Bosco, V. Curri, A. Carena, P. Poggiolini, F. Forghieri, “On the Performance of Nyquist-WDM Terabit Superchannels Based on PM-BPSK, PM-QPSK, PM-8QAM or PM-16QAM Subcarriers,” J. Lightwave Technol. 29(1), 53–61 (2011).
[CrossRef]

P. Poggiolini, G. Bosco, A. Carena, V. Curri, V. Miot, F. Forghieri, “Performance Dependence on Channel Baud-Rate of PM-QPSK Systems Over Uncompensated Links,” IEEE Photon. Technol. Lett. 23(1), 15–17 (2011).
[CrossRef]

Carena, A.

P. Poggiolini, G. Bosco, A. Carena, V. Curri, V. Miot, F. Forghieri, “Performance Dependence on Channel Baud-Rate of PM-QPSK Systems Over Uncompensated Links,” IEEE Photon. Technol. Lett. 23(1), 15–17 (2011).
[CrossRef]

G. Bosco, V. Curri, A. Carena, P. Poggiolini, F. Forghieri, “On the Performance of Nyquist-WDM Terabit Superchannels Based on PM-BPSK, PM-QPSK, PM-8QAM or PM-16QAM Subcarriers,” J. Lightwave Technol. 29(1), 53–61 (2011).
[CrossRef]

Chagnon, M.

Chandrasekhar, S.

Chang, G.-K.

Charlet, G.

Chouayakh, M.

M. Kuschnerov, M. Chouayakh, K. Piyawanno, B. Spinnler, E. de Man, P. Kainzmaier, M. S. Alfiad, A. Napoli, B. Lankl, “Data-aided versus blind single-carrier coherent receivers,” IEEE Photonics Journal 2(3), 387–403 (2010).
[CrossRef]

Curri, V.

P. Poggiolini, G. Bosco, A. Carena, V. Curri, V. Miot, F. Forghieri, “Performance Dependence on Channel Baud-Rate of PM-QPSK Systems Over Uncompensated Links,” IEEE Photon. Technol. Lett. 23(1), 15–17 (2011).
[CrossRef]

G. Bosco, V. Curri, A. Carena, P. Poggiolini, F. Forghieri, “On the Performance of Nyquist-WDM Terabit Superchannels Based on PM-BPSK, PM-QPSK, PM-8QAM or PM-16QAM Subcarriers,” J. Lightwave Technol. 29(1), 53–61 (2011).
[CrossRef]

de Man, E.

M. Kuschnerov, M. Chouayakh, K. Piyawanno, B. Spinnler, E. de Man, P. Kainzmaier, M. S. Alfiad, A. Napoli, B. Lankl, “Data-aided versus blind single-carrier coherent receivers,” IEEE Photonics Journal 2(3), 387–403 (2010).
[CrossRef]

Du, L. B.

Dupuy, J.

El-Sahn, Z. A.

Fan, S.-H.

Forghieri, F.

G. Bosco, V. Curri, A. Carena, P. Poggiolini, F. Forghieri, “On the Performance of Nyquist-WDM Terabit Superchannels Based on PM-BPSK, PM-QPSK, PM-8QAM or PM-16QAM Subcarriers,” J. Lightwave Technol. 29(1), 53–61 (2011).
[CrossRef]

P. Poggiolini, G. Bosco, A. Carena, V. Curri, V. Miot, F. Forghieri, “Performance Dependence on Channel Baud-Rate of PM-QPSK Systems Over Uncompensated Links,” IEEE Photon. Technol. Lett. 23(1), 15–17 (2011).
[CrossRef]

Gerstel, O.

O. Gerstel, M. Jinno, A. Lord, S. J. B. Yoo, “Elastic optical networking: a new dawn for the optical layer?” IEEE Commun. Mag. 50(2), s12–s20 (2012).
[CrossRef]

Gnauck, A. H.

Hoffmann, S.

Jinno, M.

O. Gerstel, M. Jinno, A. Lord, S. J. B. Yoo, “Elastic optical networking: a new dawn for the optical layer?” IEEE Commun. Mag. 50(2), s12–s20 (2012).
[CrossRef]

Jorge, F.

Kainzmaier, P.

M. Kuschnerov, M. Chouayakh, K. Piyawanno, B. Spinnler, E. de Man, P. Kainzmaier, M. S. Alfiad, A. Napoli, B. Lankl, “Data-aided versus blind single-carrier coherent receivers,” IEEE Photonics Journal 2(3), 387–403 (2010).
[CrossRef]

Konczykowska, A.

Kuschnerov, M.

M. Kuschnerov, M. Chouayakh, K. Piyawanno, B. Spinnler, E. de Man, P. Kainzmaier, M. S. Alfiad, A. Napoli, B. Lankl, “Data-aided versus blind single-carrier coherent receivers,” IEEE Photonics Journal 2(3), 387–403 (2010).
[CrossRef]

Lankl, B.

M. Kuschnerov, M. Chouayakh, K. Piyawanno, B. Spinnler, E. de Man, P. Kainzmaier, M. S. Alfiad, A. Napoli, B. Lankl, “Data-aided versus blind single-carrier coherent receivers,” IEEE Photonics Journal 2(3), 387–403 (2010).
[CrossRef]

Laperle, C.

K. Roberts, D. Beckett, D. Boertjes, J. Berthold, C. Laperle, “100G and beyond with digital coherent signal processing,” IEEE Commun. Mag. 48(7), 62–69 (2010).
[CrossRef]

Liu, X.

Lord, A.

O. Gerstel, M. Jinno, A. Lord, S. J. B. Yoo, “Elastic optical networking: a new dawn for the optical layer?” IEEE Commun. Mag. 50(2), s12–s20 (2012).
[CrossRef]

Lowery, A. J.

Meyr, H.

M. Oerder, H. Meyr, “Digital filter and square timing recovery,” IEEE Trans. Commun. 36(5), 605–612 (1988).
[CrossRef]

Miot, V.

P. Poggiolini, G. Bosco, A. Carena, V. Curri, V. Miot, F. Forghieri, “Performance Dependence on Channel Baud-Rate of PM-QPSK Systems Over Uncompensated Links,” IEEE Photon. Technol. Lett. 23(1), 15–17 (2011).
[CrossRef]

Morsy-Osman, M.

Mousa-Pasandi, M. E.

Napoli, A.

M. Kuschnerov, M. Chouayakh, K. Piyawanno, B. Spinnler, E. de Man, P. Kainzmaier, M. S. Alfiad, A. Napoli, B. Lankl, “Data-aided versus blind single-carrier coherent receivers,” IEEE Photonics Journal 2(3), 387–403 (2010).
[CrossRef]

Noe, R.

Oerder, M.

M. Oerder, H. Meyr, “Digital filter and square timing recovery,” IEEE Trans. Commun. 36(5), 605–612 (1988).
[CrossRef]

Painchaud, Y.

M. Morsy-Osman, M. Chagnon, X. Xu, Q. Zhuge, M. Poulin, Y. Painchaud, M. Pelletier, C. Paquet, D. V. Plant, “Colorless and preamplifierless reception using an integrated Si-photonic coherent receiver,” IEEE Photon. Technol. Lett. 25(11), 1027–1030 (2013).
[CrossRef]

Paquet, C.

M. Morsy-Osman, M. Chagnon, X. Xu, Q. Zhuge, M. Poulin, Y. Painchaud, M. Pelletier, C. Paquet, D. V. Plant, “Colorless and preamplifierless reception using an integrated Si-photonic coherent receiver,” IEEE Photon. Technol. Lett. 25(11), 1027–1030 (2013).
[CrossRef]

Peckham, D. W.

Pelletier, M.

M. Morsy-Osman, M. Chagnon, X. Xu, Q. Zhuge, M. Poulin, Y. Painchaud, M. Pelletier, C. Paquet, D. V. Plant, “Colorless and preamplifierless reception using an integrated Si-photonic coherent receiver,” IEEE Photon. Technol. Lett. 25(11), 1027–1030 (2013).
[CrossRef]

Pfau, T.

Piyawanno, K.

M. Kuschnerov, M. Chouayakh, K. Piyawanno, B. Spinnler, E. de Man, P. Kainzmaier, M. S. Alfiad, A. Napoli, B. Lankl, “Data-aided versus blind single-carrier coherent receivers,” IEEE Photonics Journal 2(3), 387–403 (2010).
[CrossRef]

Plant, D. V.

Poggiolini, P.

G. Bosco, V. Curri, A. Carena, P. Poggiolini, F. Forghieri, “On the Performance of Nyquist-WDM Terabit Superchannels Based on PM-BPSK, PM-QPSK, PM-8QAM or PM-16QAM Subcarriers,” J. Lightwave Technol. 29(1), 53–61 (2011).
[CrossRef]

P. Poggiolini, G. Bosco, A. Carena, V. Curri, V. Miot, F. Forghieri, “Performance Dependence on Channel Baud-Rate of PM-QPSK Systems Over Uncompensated Links,” IEEE Photon. Technol. Lett. 23(1), 15–17 (2011).
[CrossRef]

Poulin, M.

M. Morsy-Osman, M. Chagnon, X. Xu, Q. Zhuge, M. Poulin, Y. Painchaud, M. Pelletier, C. Paquet, D. V. Plant, “Colorless and preamplifierless reception using an integrated Si-photonic coherent receiver,” IEEE Photon. Technol. Lett. 25(11), 1027–1030 (2013).
[CrossRef]

Qian, D.

Qiu, M.

Riet, M.

Roberts, K.

K. Roberts, D. Beckett, D. Boertjes, J. Berthold, C. Laperle, “100G and beyond with digital coherent signal processing,” IEEE Commun. Mag. 48(7), 62–69 (2010).
[CrossRef]

Spinnler, B.

M. Kuschnerov, M. Chouayakh, K. Piyawanno, B. Spinnler, E. de Man, P. Kainzmaier, M. S. Alfiad, A. Napoli, B. Lankl, “Data-aided versus blind single-carrier coherent receivers,” IEEE Photonics Journal 2(3), 387–403 (2010).
[CrossRef]

Winzer, P. J.

Xu, X.

Yoo, S. J. B.

O. Gerstel, M. Jinno, A. Lord, S. J. B. Yoo, “Elastic optical networking: a new dawn for the optical layer?” IEEE Commun. Mag. 50(2), s12–s20 (2012).
[CrossRef]

Yu, J.

Zhu, B.

Zhuge, Q.

IEEE Commun. Mag. (2)

O. Gerstel, M. Jinno, A. Lord, S. J. B. Yoo, “Elastic optical networking: a new dawn for the optical layer?” IEEE Commun. Mag. 50(2), s12–s20 (2012).
[CrossRef]

K. Roberts, D. Beckett, D. Boertjes, J. Berthold, C. Laperle, “100G and beyond with digital coherent signal processing,” IEEE Commun. Mag. 48(7), 62–69 (2010).
[CrossRef]

IEEE Photon. Technol. Lett. (2)

P. Poggiolini, G. Bosco, A. Carena, V. Curri, V. Miot, F. Forghieri, “Performance Dependence on Channel Baud-Rate of PM-QPSK Systems Over Uncompensated Links,” IEEE Photon. Technol. Lett. 23(1), 15–17 (2011).
[CrossRef]

M. Morsy-Osman, M. Chagnon, X. Xu, Q. Zhuge, M. Poulin, Y. Painchaud, M. Pelletier, C. Paquet, D. V. Plant, “Colorless and preamplifierless reception using an integrated Si-photonic coherent receiver,” IEEE Photon. Technol. Lett. 25(11), 1027–1030 (2013).
[CrossRef]

IEEE Photonics Journal (1)

M. Kuschnerov, M. Chouayakh, K. Piyawanno, B. Spinnler, E. de Man, P. Kainzmaier, M. S. Alfiad, A. Napoli, B. Lankl, “Data-aided versus blind single-carrier coherent receivers,” IEEE Photonics Journal 2(3), 387–403 (2010).
[CrossRef]

IEEE Trans. Commun. (1)

M. Oerder, H. Meyr, “Digital filter and square timing recovery,” IEEE Trans. Commun. 36(5), 605–612 (1988).
[CrossRef]

J. Lightwave Technol. (5)

Opt. Express (4)

Other (5)

Q. Zhuge, M. Morsy-Osman, M. Chagnon, X. Xu, M. Qiu, and D. V. Plant, “Demonstration of energy-efficient and format-transparent digital signal processing for Tb/s flexible transceiver,” in Proc. ACP'13, Paper. AF2E.7 (2013).
[CrossRef]

K. Piyawanno, M. Kuschnerov, B. Spinnler, and B. Lankl, “Low complexity carrier recovery for coherent QAM using superscalar parallelization,” in Proc. ECOC'10, Paper. We.7.A.3 (2010).
[CrossRef]

Ciena Press Releases, “BT and Ciena Light World’s First 800G Super-Channel,” (2013), http://www.ciena.com/about/newsroom/press-releases/BT-and-Ciena-Light-Worlds-First-800G-Super-Channel.html?campaign=X379513&src=blog

Y. Huang, E. Ip, P. N. Ji, Y. Shao, T. Wang, Y. Aono, Y. Yano, and T. Tajima, “Terabit/s optical superchannel with flexible modulation format for dynamic distance/route transmission,” in Proc.OFC'12, Paper. OM3H.4 (2012).
[CrossRef]

K. Roberts and C. Laperle, “Flexible transceivers,” in Proc. ECOC'12, Paper. We.3.A.3 (2012).
[CrossRef]

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Figures (11)

Fig. 1
Fig. 1

Generic structure of a (a) flexible transmitter and (b) receiver. (c) Proposed receiver-side DSP. E/O: electrical-to-optical conversion. O/E: optical-to-electrical conversion. Sync.: synchronization.

Fig. 2
Fig. 2

(a) The block diagram of the proposed tracking stage DSP. (b) The structure of one transmitted frame. Sp: special pilot symbol. Rd: random pilot symbol.

Fig. 3
Fig. 3

(a) BER versus FO drifting rate. (b) BER versus polarization rotation drifting rate. D.C.: differential coding.

Fig. 4
Fig. 4

(a) Back-to-back performance. (b) Transmission performance. (c) BER versus power at 240 km.

Fig. 5
Fig. 5

Experimental setup. EDFA: Erbium-doped fiber amplifiers. FPGA: field-programmable gate array. GFF: gain flattening filter. LO: local oscillator. ODL: optical delay line. PBS/PBC: polarization beam splitter/combiner. PC: polarization controller. SW: switch.

Fig. 6
Fig. 6

Spectrum of different modulation formats.

Fig. 7
Fig. 7

Transmission performance comparison of different bandwidth-adaptive schemes for 8QAM.

Fig. 8
Fig. 8

Back-to-back performance of the 5th sub-channel. The LMS + PLL scheme is with differential coding.

Fig. 9
Fig. 9

(a) BER versus power of the 5th sub-channel and (b) BERs of individual sub-channels at two distances for each modulation format.

Fig. 10
Fig. 10

Constellations of (a) QPSK, (b) 8QAM and (c) 16QAM at back-to-back transmission. Constellations of (d) QPSK at 6240 km, (e) 8QAM at 2880 km and (f) 16QAM at 1680 km.

Fig. 11
Fig. 11

Comparison of the transmission performance for the 5th sub-channel with and without a filter at the receiver.

Equations (5)

Equations on this page are rendered with MathJax. Learn more.

R=[ a b b * a * ]=[ cos(θ) sin(θ) sin(θ) cos(θ) ]
| b |= 0.5( 1Re{ r x [1] r x * [2] r y [1] r y * [2] } )
a+b=arg{ ( r x [1] r y * [2]+ r y * [1] r x [2] ) }
Δθ=asin[ Re(b) ]=asin[ | b |cos(b)) ]asin[ | b |cos(a+b) ]
θ(k)=θ(k1)+gΔθ

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