Abstract

Discrete-Fourier-transform spread (DFT-S) optical Orthogonal Frequency Division Multiplexed (OFDM) signals offer improved nonlinearity performance in long haul optical communications systems, and can be used to form superchannels. In this paper we propose how DFT-S-OFDM superchannels can be generated and demultiplexed using all-optical techniques, and demonstrate the feasibility using numerical simulations. We also discuss how each wavelength channel is similar to recently proposed Orthogonally Time-Division Multiplexed (OrthTDM) systems using periodic-sinc pulses from, for example, a Nyquist laser. The key difference between OrthTDM and DFT-S-OFDM is the synchronization of the symbol boundaries of every modulation tributary; because of this we show that OrthTDM cannot be formed into superchannels that can be demultiplexed without penalties, but DFT-S-OFDM can be.

© 2014 Optical Society of America

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References

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  1. M. Wu and Z. Qiu, “Power de-rating reduction for DFT-S-OFDM system,” in Wireless, Mobile and Multimedia Networks, 2006 IET International Conference on (Hangzhou, China, 2006), pp. 1–4.
  2. Q. Yang, Z. He, Z. Yang, S. Yu, X. Yi, and W. Shieh, “Coherent optical DFT-spread OFDM transmission using orthogonal band multiplexing,” Opt. Express 20(3), 2379–2385 (2012).
    [Crossref] [PubMed]
  3. Y. Tang, W. Shieh, and B. S. Krongold, “DFT-spread OFDM for fiber nonlinearity mitigation,” IEEE Photon. Technol. Lett. 22(16), 1250–1252 (2010).
    [Crossref]
  4. X. Chen, A. Li, G. Gao, and W. Shieh, “Experimental demonstration of improved fiber nonlinearity tolerance for unique-word DFT-spread OFDM systems,” Opt. Express 19(27), 26198–26207 (2011).
    [Crossref] [PubMed]
  5. Y. Ma, Y. Qi, T. Yan, C. Simin, and W. Shieh, “1-Tb/s single-channel coherent optical OFDM transmission with orthogonal-band multiplexing and subwavelength bandwidth access,” J. Lightwave Technol. 28(4), 308–315 (2010).
    [Crossref]
  6. G. Bosco, A. Carena, V. Curri, P. Poggiolini, and F. Forghieri, “Performance limits of Nyquist-WDM and CO-OFDM in high-speed PM-QPSK systems,” IEEE Photon. Technol. Lett. 22(15), 1129–1131 (2010).
    [Crossref]
  7. R. Schmogrow, M. Winter, M. Meyer, D. Hillerkuss, S. Wolf, B. Baeuerle, A. Ludwig, B. Nebendahl, S. Ben-Ezra, J. Meyer, M. Dreschmann, M. Huebner, J. Becker, C. Koos, W. Freude, and J. Leuthold, “Real-time Nyquist pulse generation beyond 100 Gbit/s and its relation to OFDM,” Opt. Express 20(1), 317–337 (2012).
    [Crossref] [PubMed]
  8. D. Hillerkuss, R. Schmogrow, M. Meyer, S. Wolf, M. Jordan, P. Kleinow, N. Lindenmann, P. C. Schindler, A. Melikyan, X. Yang, S. Ben-Ezra, B. Nebendahl, M. Dreschmann, J. Meyer, F. Parmigiani, P. Petropoulos, B. Resan, A. Oehler, K. Weingarten, L. Altenhain, T. Ellermeyer, M. Moeller, M. Huebner, J. Becker, C. Koos, W. Freude, and J. Leuthold, “Single-laser 32.5 Tbit/s Nyquist WDM transmission,” J. Opt. Commun. Netw. 4(10), 715–723 (2012).
    [Crossref]
  9. G. Bosco, V. Curri, A. Carena, P. Poggiolini, and 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]
  10. M. Nakazawa, T. Hirooka, P. Ruan, and P. Guan, “Ultrahigh-speed “orthogonal” TDM transmission with an optical Nyquist pulse train,” Opt. Express 20(2), 1129–1140 (2012).
    [Crossref] [PubMed]
  11. M. A. Soto, M. Alem, M. Amin Shoaie, A. Vedadi, C. S. Brès, L. Thévenaz, and T. Schneider, “Optical sinc-shaped Nyquist pulses of exceptional quality,” Nat. Commun. 4, 2898 (2013).
    [Crossref] [PubMed]
  12. M. Nakazawa, M. Yoshida, and T. Hirooka, “The Nyquist laser,” Optica 1(1), 15–22 (2014).
    [Crossref]
  13. J. Zhang, J. Yu, Y. Fang, and N. Chi, “High speed all optical Nyquist signal generation and full-band coherent detection,” Sci. Rep. 4, 06156 (2014).
  14. W. Shieh and C. Athaudage, “Coherent optical orthogonal frequency division multiplexing,” Electron. Lett. 42(10), 587–588 (2006).
    [Crossref]
  15. O. Gaete, L. Coelho, B. Spinnler, and N. Hanik, “Pulse shaping using the discrete Fourier transform for direct detection optical systems,” in Transparent Optical Networks (ICTON), 2011 13th International Conference on(2011), p. We.A1.2.
    [Crossref]
  16. A. J. Lowery and L. B. Du, “Optical orthogonal division multiplexing for long haul optical communications: A review of the first five years,” Opt. Fiber Technol. 17(5), 421–438 (2011).
    [Crossref]
  17. A. J. Lowery, “Design of arrayed-waveguide grating routers for use as optical OFDM demultiplexers,” Opt. Express 18(13), 14129–14143 (2010).
    [Crossref] [PubMed]
  18. G. Cincotti, “Optical implementation of the Fourier transform for OFDM transmission,” in Transparent Optical Networks (ICTON), 2011 13th International Conference on(2011), pp. 1–4.
    [Crossref]
  19. M. E. Marhic, “Discrete Fourier transforms by single-mode star networks,” Opt. Lett. 12(1), 63–65 (1987).
    [Crossref] [PubMed]
  20. J. Schröder, M. A. F. Roelens, L. B. Du, A. J. Lowery, S. Frisken, and B. J. Eggleton, “An optical FPGA: Reconfigurable simultaneous multi-output spectral pulse-shaping for linear optical processing,” Opt. Express 21(1), 690–697 (2013).
    [Crossref] [PubMed]
  21. J. B. Schroeder, L. B. Du, M. M. Morshed, B. Eggleton, and A. J. Lowery, “Colorless flexible signal generator for elastic networks andrapid prototyping,” in Optical Fiber Communication Conference 2013(Optical Society of America, Anaheim, California, 2013), p. JW2A.44.

2014 (2)

M. Nakazawa, M. Yoshida, and T. Hirooka, “The Nyquist laser,” Optica 1(1), 15–22 (2014).
[Crossref]

J. Zhang, J. Yu, Y. Fang, and N. Chi, “High speed all optical Nyquist signal generation and full-band coherent detection,” Sci. Rep. 4, 06156 (2014).

2013 (2)

J. Schröder, M. A. F. Roelens, L. B. Du, A. J. Lowery, S. Frisken, and B. J. Eggleton, “An optical FPGA: Reconfigurable simultaneous multi-output spectral pulse-shaping for linear optical processing,” Opt. Express 21(1), 690–697 (2013).
[Crossref] [PubMed]

M. A. Soto, M. Alem, M. Amin Shoaie, A. Vedadi, C. S. Brès, L. Thévenaz, and T. Schneider, “Optical sinc-shaped Nyquist pulses of exceptional quality,” Nat. Commun. 4, 2898 (2013).
[Crossref] [PubMed]

2012 (4)

2011 (3)

2010 (4)

A. J. Lowery, “Design of arrayed-waveguide grating routers for use as optical OFDM demultiplexers,” Opt. Express 18(13), 14129–14143 (2010).
[Crossref] [PubMed]

Y. Ma, Y. Qi, T. Yan, C. Simin, and W. Shieh, “1-Tb/s single-channel coherent optical OFDM transmission with orthogonal-band multiplexing and subwavelength bandwidth access,” J. Lightwave Technol. 28(4), 308–315 (2010).
[Crossref]

G. Bosco, A. Carena, V. Curri, P. Poggiolini, and F. Forghieri, “Performance limits of Nyquist-WDM and CO-OFDM in high-speed PM-QPSK systems,” IEEE Photon. Technol. Lett. 22(15), 1129–1131 (2010).
[Crossref]

Y. Tang, W. Shieh, and B. S. Krongold, “DFT-spread OFDM for fiber nonlinearity mitigation,” IEEE Photon. Technol. Lett. 22(16), 1250–1252 (2010).
[Crossref]

2006 (1)

W. Shieh and C. Athaudage, “Coherent optical orthogonal frequency division multiplexing,” Electron. Lett. 42(10), 587–588 (2006).
[Crossref]

1987 (1)

Alem, M.

M. A. Soto, M. Alem, M. Amin Shoaie, A. Vedadi, C. S. Brès, L. Thévenaz, and T. Schneider, “Optical sinc-shaped Nyquist pulses of exceptional quality,” Nat. Commun. 4, 2898 (2013).
[Crossref] [PubMed]

Altenhain, L.

Amin Shoaie, M.

M. A. Soto, M. Alem, M. Amin Shoaie, A. Vedadi, C. S. Brès, L. Thévenaz, and T. Schneider, “Optical sinc-shaped Nyquist pulses of exceptional quality,” Nat. Commun. 4, 2898 (2013).
[Crossref] [PubMed]

Athaudage, C.

W. Shieh and C. Athaudage, “Coherent optical orthogonal frequency division multiplexing,” Electron. Lett. 42(10), 587–588 (2006).
[Crossref]

Baeuerle, B.

Becker, J.

Ben-Ezra, S.

Bosco, G.

G. Bosco, V. Curri, A. Carena, P. Poggiolini, and 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]

G. Bosco, A. Carena, V. Curri, P. Poggiolini, and F. Forghieri, “Performance limits of Nyquist-WDM and CO-OFDM in high-speed PM-QPSK systems,” IEEE Photon. Technol. Lett. 22(15), 1129–1131 (2010).
[Crossref]

Brès, C. S.

M. A. Soto, M. Alem, M. Amin Shoaie, A. Vedadi, C. S. Brès, L. Thévenaz, and T. Schneider, “Optical sinc-shaped Nyquist pulses of exceptional quality,” Nat. Commun. 4, 2898 (2013).
[Crossref] [PubMed]

Carena, A.

G. Bosco, V. Curri, A. Carena, P. Poggiolini, and 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]

G. Bosco, A. Carena, V. Curri, P. Poggiolini, and F. Forghieri, “Performance limits of Nyquist-WDM and CO-OFDM in high-speed PM-QPSK systems,” IEEE Photon. Technol. Lett. 22(15), 1129–1131 (2010).
[Crossref]

Chen, X.

Chi, N.

J. Zhang, J. Yu, Y. Fang, and N. Chi, “High speed all optical Nyquist signal generation and full-band coherent detection,” Sci. Rep. 4, 06156 (2014).

Curri, V.

G. Bosco, V. Curri, A. Carena, P. Poggiolini, and 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]

G. Bosco, A. Carena, V. Curri, P. Poggiolini, and F. Forghieri, “Performance limits of Nyquist-WDM and CO-OFDM in high-speed PM-QPSK systems,” IEEE Photon. Technol. Lett. 22(15), 1129–1131 (2010).
[Crossref]

Dreschmann, M.

Du, L. B.

J. Schröder, M. A. F. Roelens, L. B. Du, A. J. Lowery, S. Frisken, and B. J. Eggleton, “An optical FPGA: Reconfigurable simultaneous multi-output spectral pulse-shaping for linear optical processing,” Opt. Express 21(1), 690–697 (2013).
[Crossref] [PubMed]

A. J. Lowery and L. B. Du, “Optical orthogonal division multiplexing for long haul optical communications: A review of the first five years,” Opt. Fiber Technol. 17(5), 421–438 (2011).
[Crossref]

Eggleton, B. J.

Ellermeyer, T.

Fang, Y.

J. Zhang, J. Yu, Y. Fang, and N. Chi, “High speed all optical Nyquist signal generation and full-band coherent detection,” Sci. Rep. 4, 06156 (2014).

Forghieri, F.

G. Bosco, V. Curri, A. Carena, P. Poggiolini, and 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]

G. Bosco, A. Carena, V. Curri, P. Poggiolini, and F. Forghieri, “Performance limits of Nyquist-WDM and CO-OFDM in high-speed PM-QPSK systems,” IEEE Photon. Technol. Lett. 22(15), 1129–1131 (2010).
[Crossref]

Freude, W.

Frisken, S.

Gao, G.

Guan, P.

He, Z.

Hillerkuss, D.

Hirooka, T.

Huebner, M.

Jordan, M.

Kleinow, P.

Koos, C.

Krongold, B. S.

Y. Tang, W. Shieh, and B. S. Krongold, “DFT-spread OFDM for fiber nonlinearity mitigation,” IEEE Photon. Technol. Lett. 22(16), 1250–1252 (2010).
[Crossref]

Leuthold, J.

Li, A.

Lindenmann, N.

Lowery, A. J.

Ludwig, A.

Ma, Y.

Marhic, M. E.

Melikyan, A.

Meyer, J.

Meyer, M.

Moeller, M.

Nakazawa, M.

Nebendahl, B.

Oehler, A.

Parmigiani, F.

Petropoulos, P.

Poggiolini, P.

G. Bosco, V. Curri, A. Carena, P. Poggiolini, and 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]

G. Bosco, A. Carena, V. Curri, P. Poggiolini, and F. Forghieri, “Performance limits of Nyquist-WDM and CO-OFDM in high-speed PM-QPSK systems,” IEEE Photon. Technol. Lett. 22(15), 1129–1131 (2010).
[Crossref]

Qi, Y.

Resan, B.

Roelens, M. A. F.

Ruan, P.

Schindler, P. C.

Schmogrow, R.

Schneider, T.

M. A. Soto, M. Alem, M. Amin Shoaie, A. Vedadi, C. S. Brès, L. Thévenaz, and T. Schneider, “Optical sinc-shaped Nyquist pulses of exceptional quality,” Nat. Commun. 4, 2898 (2013).
[Crossref] [PubMed]

Schröder, J.

Shieh, W.

Simin, C.

Soto, M. A.

M. A. Soto, M. Alem, M. Amin Shoaie, A. Vedadi, C. S. Brès, L. Thévenaz, and T. Schneider, “Optical sinc-shaped Nyquist pulses of exceptional quality,” Nat. Commun. 4, 2898 (2013).
[Crossref] [PubMed]

Tang, Y.

Y. Tang, W. Shieh, and B. S. Krongold, “DFT-spread OFDM for fiber nonlinearity mitigation,” IEEE Photon. Technol. Lett. 22(16), 1250–1252 (2010).
[Crossref]

Thévenaz, L.

M. A. Soto, M. Alem, M. Amin Shoaie, A. Vedadi, C. S. Brès, L. Thévenaz, and T. Schneider, “Optical sinc-shaped Nyquist pulses of exceptional quality,” Nat. Commun. 4, 2898 (2013).
[Crossref] [PubMed]

Vedadi, A.

M. A. Soto, M. Alem, M. Amin Shoaie, A. Vedadi, C. S. Brès, L. Thévenaz, and T. Schneider, “Optical sinc-shaped Nyquist pulses of exceptional quality,” Nat. Commun. 4, 2898 (2013).
[Crossref] [PubMed]

Weingarten, K.

Winter, M.

Wolf, S.

Yan, T.

Yang, Q.

Yang, X.

Yang, Z.

Yi, X.

Yoshida, M.

Yu, J.

J. Zhang, J. Yu, Y. Fang, and N. Chi, “High speed all optical Nyquist signal generation and full-band coherent detection,” Sci. Rep. 4, 06156 (2014).

Yu, S.

Zhang, J.

J. Zhang, J. Yu, Y. Fang, and N. Chi, “High speed all optical Nyquist signal generation and full-band coherent detection,” Sci. Rep. 4, 06156 (2014).

Electron. Lett. (1)

W. Shieh and C. Athaudage, “Coherent optical orthogonal frequency division multiplexing,” Electron. Lett. 42(10), 587–588 (2006).
[Crossref]

IEEE Photon. Technol. Lett. (2)

Y. Tang, W. Shieh, and B. S. Krongold, “DFT-spread OFDM for fiber nonlinearity mitigation,” IEEE Photon. Technol. Lett. 22(16), 1250–1252 (2010).
[Crossref]

G. Bosco, A. Carena, V. Curri, P. Poggiolini, and F. Forghieri, “Performance limits of Nyquist-WDM and CO-OFDM in high-speed PM-QPSK systems,” IEEE Photon. Technol. Lett. 22(15), 1129–1131 (2010).
[Crossref]

J. Lightwave Technol. (2)

J. Opt. Commun. Netw. (1)

Nat. Commun. (1)

M. A. Soto, M. Alem, M. Amin Shoaie, A. Vedadi, C. S. Brès, L. Thévenaz, and T. Schneider, “Optical sinc-shaped Nyquist pulses of exceptional quality,” Nat. Commun. 4, 2898 (2013).
[Crossref] [PubMed]

Opt. Express (6)

Opt. Fiber Technol. (1)

A. J. Lowery and L. B. Du, “Optical orthogonal division multiplexing for long haul optical communications: A review of the first five years,” Opt. Fiber Technol. 17(5), 421–438 (2011).
[Crossref]

Opt. Lett. (1)

Optica (1)

Sci. Rep. (1)

J. Zhang, J. Yu, Y. Fang, and N. Chi, “High speed all optical Nyquist signal generation and full-band coherent detection,” Sci. Rep. 4, 06156 (2014).

Other (4)

G. Cincotti, “Optical implementation of the Fourier transform for OFDM transmission,” in Transparent Optical Networks (ICTON), 2011 13th International Conference on(2011), pp. 1–4.
[Crossref]

O. Gaete, L. Coelho, B. Spinnler, and N. Hanik, “Pulse shaping using the discrete Fourier transform for direct detection optical systems,” in Transparent Optical Networks (ICTON), 2011 13th International Conference on(2011), p. We.A1.2.
[Crossref]

M. Wu and Z. Qiu, “Power de-rating reduction for DFT-S-OFDM system,” in Wireless, Mobile and Multimedia Networks, 2006 IET International Conference on (Hangzhou, China, 2006), pp. 1–4.

J. B. Schroeder, L. B. Du, M. M. Morshed, B. Eggleton, and A. J. Lowery, “Colorless flexible signal generator for elastic networks andrapid prototyping,” in Optical Fiber Communication Conference 2013(Optical Society of America, Anaheim, California, 2013), p. JW2A.44.

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Figures (17)

Fig. 1
Fig. 1

Three methods of generating trains of periodic sinc or Nyquist pulses.

Fig. 2
Fig. 2

Orthogonal Time Division Multiplexing (OrthTDM) of N periodic pulse trains.

Fig. 3
Fig. 3

Modulation of the input pulse train in one tributary (m = 0) of the OrthTDM multiplexer.

Fig. 4
Fig. 4

Time averaged optical spectrum of the OrthTDM signal.

Fig. 5
Fig. 5

Eye diagram of the OrthTDM signal showing optimum sampling points at 6.25 and 12.5 ps.

Fig. 6
Fig. 6

Optical spectrum after combining three OrthTDM channels to form WDM.

Fig. 7
Fig. 7

Optical waveform after combining three OrthTDM channels to form a WDM superchannel.

Fig. 8
Fig. 8

Eye diagram after combining three OrthTDM channels to form a WDM superchannel.

Fig. 9
Fig. 9

Eye diagram of the central WDM channel after demultiplexing with a rectangular filter.

Fig. 10
Fig. 10

Effect of a rectangular optical filter on a single transmitted OrthTDM channel.

Fig. 11
Fig. 11

DFT-S-OOFDM wavelength channel transmitter. The output waveform for a single non-zero data input is shown.

Fig. 12
Fig. 12

One wavelength channel of a DFT-S-OFDM transmitter implemented in optics. Note how the positions of the modulators and delays have been reversed compared with Fig. 2. The data signals driving the modulators are assumed to be time-aligned. Two waveforms before the combiner are illustrated, showing how the waveform for the N/2 tributary wraps around within a symbol period.

Fig. 13
Fig. 13

Time-averaged spectrum for the 3-wavelength DFT-S-OFDM modulation system shown in Fig. 12. Note the flat top of the main lobe, which is different to that reported by Soto et al.

Fig. 14
Fig. 14

Overlaid spectra for tributaries of one wavelength channel for the (left) Modulators after Delay (Fig. 12), and (right) Delays after Modulators (Fig. 2) schemes. The Modulators after Delay spectra (left) show that the relative timing of the data symbols and the peak of the sinc spectra have a dramatic effect on the spectrum of each tributary.

Fig. 15
Fig. 15

Processed received signal set to receive a transmitted channel with all zeros.

Fig. 16
Fig. 16

Processed received signal set to receive a transmitted channel with random data (zoomed in time-axis).

Fig. 17
Fig. 17

One electrical (top) and three optical methods of constructing wavelength channels that can (or cannot) be used in superchannel systems. Optical pulse shaping to generate N-WDM and/or OFDM (second row) was demonstrated in [21].

Equations (13)

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

X PS (f)= rect N T (f 1 2T )× n= δ( fn/T ) = n= N 2 +1 N 2 δ( fn/T ) .
rect N T (f)=1 [ N 2T <f< N 2T ]; 0.5 [ f= N 2T or N 2T ]; 0 otherwise.
x PS (t)=( N T sinc( tN T ) e j πt T )*( T. k= δ( tk.T ) ) =N k= sinc( tN T k.N ) × e jπ( t T k ) = n= N 2 +1 n= N 2 e j 2πnt T .
sinc(x)= sin(πx) πx .
x OrthTDM,m (t)=N k= sinc( tN T kNm ) e jπ( t T k m N ) × h= D m,h rect T ( thT mT N ) .
rect T (t)=1 [ T 2 <t< T 2 ]; 0.5 [ t= T 2 or T 2 ]; 0 otherwise.
x OrthTDM (t)= m=0 N1 x OrthTDM,m (t) .
| X OrthTDM,m (f) | 2 = | FT{ rect T ( t )×N k= sinc( tN T kN ) e jπ( t T k ) } | 2 .
| X OrthTDM,m (f) | 2 = | Tsinc( fT )* n= N 2 +1 N 2 δ( fn/T ) | 2 .
| X OrthTDM,m (f) | 2 = | T n= N 2 +1 N 2 sinc( fn/T ) | 2 .
x DFTS,m (t)=N k= sinc( tN T kNm ) exp jπ( t T k m N ) × h= D m,h rec t T ( thT ) .
| X DFTS,m (f) | 2 = | FT{ rect T ( t mT N )×N k= sinc( tN T kN ) e jπ( t T k ) } | 2 .
| X DFTS,m (f) | 2 = | T n= N 2 +1 N 2 sinc( fn/T ) e j2π(fn/T) mT N | 2 .

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