Abstract

We demonstrate two efficient processing techniques for Nyquist signals, namely computation of signals using dynamic precision as well as arbitrary rational oversampling factors. With these techniques along with massively parallel processing it becomes possible to generate and receive high data rate Nyquist signals with flexible symbol rates and bandwidths, a feature which is highly desirable for novel flexgrid networks. We achieved maximum bit rates of 252 Gbit/s in real-time.

© 2014 Optical Society of America

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References

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    [Crossref]
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2013 (1)

2012 (5)

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Error vector magnitude as a performance measure for advanced modulation formats,” IEEE Photon. Technol. Lett. 24(1), 61–63 (2012).
[Crossref]

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Corrections to: Error vector magnitude as a performance measure for advanced modulation formats: erratum,” IEEE Photon. Technol. Lett. 24(23), 2198 (2012).
[Crossref]

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]

R. Bouziane, R. Schmogrow, D. Hillerkuss, P. A. Milder, C. Koos, W. Freude, J. Leuthold, P. Bayvel, and R. I. Killey, “Generation and transmission of 85.4 Gb/s real-time 16QAM coherent optical OFDM signals over 400 km SSMF with preamble-less reception,” Opt. Express 20(19), 21612–21617 (2012).
[Crossref] [PubMed]

R. Schmogrow, R. Bouziane, M. Meyer, P. A. Milder, P. C. Schindler, R. I. Killey, P. Bayvel, C. Koos, W. Freude, and J. Leuthold, “Real-time OFDM or Nyquist pulse generation--which performs better with limited resources?” Opt. Express 20(26), B543–B551 (2012).
[Crossref] [PubMed]

2011 (3)

2010 (1)

2008 (1)

2006 (1)

T. Mizuochi, “Recent progress in forward error correction and its interplay with transmission impairments,” IEEE J. Sel. Top. Quantum Electron. 12(4), 544–554 (2006).
[Crossref]

1973 (1)

S. D. Personick, “Receiver design for digital fiber optic communication systems, I,” Bell Syst. Tech. J. 52(6), 843–874 (1973).
[Crossref]

1928 (1)

H. Nyquist, “Certain topics in telegraph transmission theory,” Trans. Am. Inst. Electr. Eng. 47(2), 617–644 (1928).
[Crossref]

Adhikari, S.

Baeuerle, B.

Bao, H.

Bayvel, P.

Becker, J.

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]

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Corrections to: Error vector magnitude as a performance measure for advanced modulation formats: erratum,” IEEE Photon. Technol. Lett. 24(23), 2198 (2012).
[Crossref]

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Error vector magnitude as a performance measure for advanced modulation formats,” IEEE Photon. Technol. Lett. 24(1), 61–63 (2012).
[Crossref]

R. Schmogrow, M. Winter, D. Hillerkuss, B. Nebendahl, S. Ben-Ezra, J. Meyer, M. Dreschmann, M. Huebner, J. Becker, C. Koos, W. Freude, and J. Leuthold, “Real-time OFDM transmitter beyond 100 Gbit/s,” Opt. Express 19(13), 12740–12749 (2011).
[Crossref] [PubMed]

Ben-Ezra, S.

Bosco, G.

Bouziane, R.

Carena, A.

Chandrasekhar, S.

Chen, Y.

Curri, V.

Dreschmann, M.

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Corrections to: Error vector magnitude as a performance measure for advanced modulation formats: erratum,” IEEE Photon. Technol. Lett. 24(23), 2198 (2012).
[Crossref]

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Error vector magnitude as a performance measure for advanced modulation formats,” IEEE Photon. Technol. Lett. 24(1), 61–63 (2012).
[Crossref]

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]

R. Schmogrow, M. Winter, D. Hillerkuss, B. Nebendahl, S. Ben-Ezra, J. Meyer, M. Dreschmann, M. Huebner, J. Becker, C. Koos, W. Freude, and J. Leuthold, “Real-time OFDM transmitter beyond 100 Gbit/s,” Opt. Express 19(13), 12740–12749 (2011).
[Crossref] [PubMed]

Forghieri, F.

Freude, W.

R. Schmogrow, S. Ben-Ezra, P. Schindler, B. Nebendahl, C. Koos, W. Freude, and J. Leuthold, “Pulse-Shaping With Digital, Electrical, and Optical Filters − A Comparison,” J. Lightwave Technol. 31(15), 2570–2577 (2013).
[Crossref]

R. Schmogrow, R. Bouziane, M. Meyer, P. A. Milder, P. C. Schindler, R. I. Killey, P. Bayvel, C. Koos, W. Freude, and J. Leuthold, “Real-time OFDM or Nyquist pulse generation--which performs better with limited resources?” Opt. Express 20(26), B543–B551 (2012).
[Crossref] [PubMed]

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]

R. Bouziane, R. Schmogrow, D. Hillerkuss, P. A. Milder, C. Koos, W. Freude, J. Leuthold, P. Bayvel, and R. I. Killey, “Generation and transmission of 85.4 Gb/s real-time 16QAM coherent optical OFDM signals over 400 km SSMF with preamble-less reception,” Opt. Express 20(19), 21612–21617 (2012).
[Crossref] [PubMed]

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Error vector magnitude as a performance measure for advanced modulation formats,” IEEE Photon. Technol. Lett. 24(1), 61–63 (2012).
[Crossref]

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Corrections to: Error vector magnitude as a performance measure for advanced modulation formats: erratum,” IEEE Photon. Technol. Lett. 24(23), 2198 (2012).
[Crossref]

R. Schmogrow, M. Winter, D. Hillerkuss, B. Nebendahl, S. Ben-Ezra, J. Meyer, M. Dreschmann, M. Huebner, J. Becker, C. Koos, W. Freude, and J. Leuthold, “Real-time OFDM transmitter beyond 100 Gbit/s,” Opt. Express 19(13), 12740–12749 (2011).
[Crossref] [PubMed]

Hanik, N.

Hillerkuss, D.

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]

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Corrections to: Error vector magnitude as a performance measure for advanced modulation formats: erratum,” IEEE Photon. Technol. Lett. 24(23), 2198 (2012).
[Crossref]

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Error vector magnitude as a performance measure for advanced modulation formats,” IEEE Photon. Technol. Lett. 24(1), 61–63 (2012).
[Crossref]

R. Bouziane, R. Schmogrow, D. Hillerkuss, P. A. Milder, C. Koos, W. Freude, J. Leuthold, P. Bayvel, and R. I. Killey, “Generation and transmission of 85.4 Gb/s real-time 16QAM coherent optical OFDM signals over 400 km SSMF with preamble-less reception,” Opt. Express 20(19), 21612–21617 (2012).
[Crossref] [PubMed]

R. Schmogrow, M. Winter, D. Hillerkuss, B. Nebendahl, S. Ben-Ezra, J. Meyer, M. Dreschmann, M. Huebner, J. Becker, C. Koos, W. Freude, and J. Leuthold, “Real-time OFDM transmitter beyond 100 Gbit/s,” Opt. Express 19(13), 12740–12749 (2011).
[Crossref] [PubMed]

Huebner, M.

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Error vector magnitude as a performance measure for advanced modulation formats,” IEEE Photon. Technol. Lett. 24(1), 61–63 (2012).
[Crossref]

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Corrections to: Error vector magnitude as a performance measure for advanced modulation formats: erratum,” IEEE Photon. Technol. Lett. 24(23), 2198 (2012).
[Crossref]

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]

R. Schmogrow, M. Winter, D. Hillerkuss, B. Nebendahl, S. Ben-Ezra, J. Meyer, M. Dreschmann, M. Huebner, J. Becker, C. Koos, W. Freude, and J. Leuthold, “Real-time OFDM transmitter beyond 100 Gbit/s,” Opt. Express 19(13), 12740–12749 (2011).
[Crossref] [PubMed]

Inan, B.

Jansen, S. L.

Josten, A.

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Error vector magnitude as a performance measure for advanced modulation formats,” IEEE Photon. Technol. Lett. 24(1), 61–63 (2012).
[Crossref]

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Corrections to: Error vector magnitude as a performance measure for advanced modulation formats: erratum,” IEEE Photon. Technol. Lett. 24(23), 2198 (2012).
[Crossref]

Kainzmaier, P.

Kaneda, N.

Karakaya, O.

Killey, R. I.

Koenig, S.

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Corrections to: Error vector magnitude as a performance measure for advanced modulation formats: erratum,” IEEE Photon. Technol. Lett. 24(23), 2198 (2012).
[Crossref]

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Error vector magnitude as a performance measure for advanced modulation formats,” IEEE Photon. Technol. Lett. 24(1), 61–63 (2012).
[Crossref]

Koos, C.

R. Schmogrow, S. Ben-Ezra, P. Schindler, B. Nebendahl, C. Koos, W. Freude, and J. Leuthold, “Pulse-Shaping With Digital, Electrical, and Optical Filters − A Comparison,” J. Lightwave Technol. 31(15), 2570–2577 (2013).
[Crossref]

R. Bouziane, R. Schmogrow, D. Hillerkuss, P. A. Milder, C. Koos, W. Freude, J. Leuthold, P. Bayvel, and R. I. Killey, “Generation and transmission of 85.4 Gb/s real-time 16QAM coherent optical OFDM signals over 400 km SSMF with preamble-less reception,” Opt. Express 20(19), 21612–21617 (2012).
[Crossref] [PubMed]

R. Schmogrow, R. Bouziane, M. Meyer, P. A. Milder, P. C. Schindler, R. I. Killey, P. Bayvel, C. Koos, W. Freude, and J. Leuthold, “Real-time OFDM or Nyquist pulse generation--which performs better with limited resources?” Opt. Express 20(26), B543–B551 (2012).
[Crossref] [PubMed]

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]

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Error vector magnitude as a performance measure for advanced modulation formats,” IEEE Photon. Technol. Lett. 24(1), 61–63 (2012).
[Crossref]

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Corrections to: Error vector magnitude as a performance measure for advanced modulation formats: erratum,” IEEE Photon. Technol. Lett. 24(23), 2198 (2012).
[Crossref]

R. Schmogrow, M. Winter, D. Hillerkuss, B. Nebendahl, S. Ben-Ezra, J. Meyer, M. Dreschmann, M. Huebner, J. Becker, C. Koos, W. Freude, and J. Leuthold, “Real-time OFDM transmitter beyond 100 Gbit/s,” Opt. Express 19(13), 12740–12749 (2011).
[Crossref] [PubMed]

Leuthold, J.

R. Schmogrow, S. Ben-Ezra, P. Schindler, B. Nebendahl, C. Koos, W. Freude, and J. Leuthold, “Pulse-Shaping With Digital, Electrical, and Optical Filters − A Comparison,” J. Lightwave Technol. 31(15), 2570–2577 (2013).
[Crossref]

R. Schmogrow, R. Bouziane, M. Meyer, P. A. Milder, P. C. Schindler, R. I. Killey, P. Bayvel, C. Koos, W. Freude, and J. Leuthold, “Real-time OFDM or Nyquist pulse generation--which performs better with limited resources?” Opt. Express 20(26), B543–B551 (2012).
[Crossref] [PubMed]

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]

R. Bouziane, R. Schmogrow, D. Hillerkuss, P. A. Milder, C. Koos, W. Freude, J. Leuthold, P. Bayvel, and R. I. Killey, “Generation and transmission of 85.4 Gb/s real-time 16QAM coherent optical OFDM signals over 400 km SSMF with preamble-less reception,” Opt. Express 20(19), 21612–21617 (2012).
[Crossref] [PubMed]

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Corrections to: Error vector magnitude as a performance measure for advanced modulation formats: erratum,” IEEE Photon. Technol. Lett. 24(23), 2198 (2012).
[Crossref]

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Error vector magnitude as a performance measure for advanced modulation formats,” IEEE Photon. Technol. Lett. 24(1), 61–63 (2012).
[Crossref]

R. Schmogrow, M. Winter, D. Hillerkuss, B. Nebendahl, S. Ben-Ezra, J. Meyer, M. Dreschmann, M. Huebner, J. Becker, C. Koos, W. Freude, and J. Leuthold, “Real-time OFDM transmitter beyond 100 Gbit/s,” Opt. Express 19(13), 12740–12749 (2011).
[Crossref] [PubMed]

Liu, X.

Ludwig, A.

Meyer, J.

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]

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Corrections to: Error vector magnitude as a performance measure for advanced modulation formats: erratum,” IEEE Photon. Technol. Lett. 24(23), 2198 (2012).
[Crossref]

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Error vector magnitude as a performance measure for advanced modulation formats,” IEEE Photon. Technol. Lett. 24(1), 61–63 (2012).
[Crossref]

R. Schmogrow, M. Winter, D. Hillerkuss, B. Nebendahl, S. Ben-Ezra, J. Meyer, M. Dreschmann, M. Huebner, J. Becker, C. Koos, W. Freude, and J. Leuthold, “Real-time OFDM transmitter beyond 100 Gbit/s,” Opt. Express 19(13), 12740–12749 (2011).
[Crossref] [PubMed]

Meyer, M.

Milder, P. A.

Mizuochi, T.

T. Mizuochi, “Recent progress in forward error correction and its interplay with transmission impairments,” IEEE J. Sel. Top. Quantum Electron. 12(4), 544–554 (2006).
[Crossref]

Mocker, M.

Nebendahl, B.

R. Schmogrow, S. Ben-Ezra, P. Schindler, B. Nebendahl, C. Koos, W. Freude, and J. Leuthold, “Pulse-Shaping With Digital, Electrical, and Optical Filters − A Comparison,” J. Lightwave Technol. 31(15), 2570–2577 (2013).
[Crossref]

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]

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Error vector magnitude as a performance measure for advanced modulation formats,” IEEE Photon. Technol. Lett. 24(1), 61–63 (2012).
[Crossref]

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Corrections to: Error vector magnitude as a performance measure for advanced modulation formats: erratum,” IEEE Photon. Technol. Lett. 24(23), 2198 (2012).
[Crossref]

R. Schmogrow, M. Winter, D. Hillerkuss, B. Nebendahl, S. Ben-Ezra, J. Meyer, M. Dreschmann, M. Huebner, J. Becker, C. Koos, W. Freude, and J. Leuthold, “Real-time OFDM transmitter beyond 100 Gbit/s,” Opt. Express 19(13), 12740–12749 (2011).
[Crossref] [PubMed]

Nyquist, H.

H. Nyquist, “Certain topics in telegraph transmission theory,” Trans. Am. Inst. Electr. Eng. 47(2), 617–644 (1928).
[Crossref]

Personick, S. D.

S. D. Personick, “Receiver design for digital fiber optic communication systems, I,” Bell Syst. Tech. J. 52(6), 843–874 (1973).
[Crossref]

Poggiolini, P.

Schindler, P.

Schindler, P. C.

Schmogrow, R.

R. Schmogrow, S. Ben-Ezra, P. Schindler, B. Nebendahl, C. Koos, W. Freude, and J. Leuthold, “Pulse-Shaping With Digital, Electrical, and Optical Filters − A Comparison,” J. Lightwave Technol. 31(15), 2570–2577 (2013).
[Crossref]

R. Schmogrow, R. Bouziane, M. Meyer, P. A. Milder, P. C. Schindler, R. I. Killey, P. Bayvel, C. Koos, W. Freude, and J. Leuthold, “Real-time OFDM or Nyquist pulse generation--which performs better with limited resources?” Opt. Express 20(26), B543–B551 (2012).
[Crossref] [PubMed]

R. Bouziane, R. Schmogrow, D. Hillerkuss, P. A. Milder, C. Koos, W. Freude, J. Leuthold, P. Bayvel, and R. I. Killey, “Generation and transmission of 85.4 Gb/s real-time 16QAM coherent optical OFDM signals over 400 km SSMF with preamble-less reception,” Opt. Express 20(19), 21612–21617 (2012).
[Crossref] [PubMed]

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]

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Error vector magnitude as a performance measure for advanced modulation formats,” IEEE Photon. Technol. Lett. 24(1), 61–63 (2012).
[Crossref]

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Corrections to: Error vector magnitude as a performance measure for advanced modulation formats: erratum,” IEEE Photon. Technol. Lett. 24(23), 2198 (2012).
[Crossref]

R. Schmogrow, M. Winter, D. Hillerkuss, B. Nebendahl, S. Ben-Ezra, J. Meyer, M. Dreschmann, M. Huebner, J. Becker, C. Koos, W. Freude, and J. Leuthold, “Real-time OFDM transmitter beyond 100 Gbit/s,” Opt. Express 19(13), 12740–12749 (2011).
[Crossref] [PubMed]

Shieh, W.

Tang, Y.

von Kirchbauer, H.

Winter, M.

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]

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Corrections to: Error vector magnitude as a performance measure for advanced modulation formats: erratum,” IEEE Photon. Technol. Lett. 24(23), 2198 (2012).
[Crossref]

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Error vector magnitude as a performance measure for advanced modulation formats,” IEEE Photon. Technol. Lett. 24(1), 61–63 (2012).
[Crossref]

R. Schmogrow, M. Winter, D. Hillerkuss, B. Nebendahl, S. Ben-Ezra, J. Meyer, M. Dreschmann, M. Huebner, J. Becker, C. Koos, W. Freude, and J. Leuthold, “Real-time OFDM transmitter beyond 100 Gbit/s,” Opt. Express 19(13), 12740–12749 (2011).
[Crossref] [PubMed]

Wolf, S.

Yang, Q.

Bell Syst. Tech. J. (1)

S. D. Personick, “Receiver design for digital fiber optic communication systems, I,” Bell Syst. Tech. J. 52(6), 843–874 (1973).
[Crossref]

IEEE J. Sel. Top. Quantum Electron. (1)

T. Mizuochi, “Recent progress in forward error correction and its interplay with transmission impairments,” IEEE J. Sel. Top. Quantum Electron. 12(4), 544–554 (2006).
[Crossref]

IEEE Photon. Technol. Lett. (2)

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Error vector magnitude as a performance measure for advanced modulation formats,” IEEE Photon. Technol. Lett. 24(1), 61–63 (2012).
[Crossref]

R. Schmogrow, B. Nebendahl, M. Winter, A. Josten, D. Hillerkuss, S. Koenig, J. Meyer, M. Dreschmann, M. Huebner, C. Koos, J. Becker, W. Freude, and J. Leuthold, “Corrections to: Error vector magnitude as a performance measure for advanced modulation formats: erratum,” IEEE Photon. Technol. Lett. 24(23), 2198 (2012).
[Crossref]

J. Lightwave Technol. (3)

Opt. Express (6)

R. Schmogrow, R. Bouziane, M. Meyer, P. A. Milder, P. C. Schindler, R. I. Killey, P. Bayvel, C. Koos, W. Freude, and J. Leuthold, “Real-time OFDM or Nyquist pulse generation--which performs better with limited resources?” Opt. Express 20(26), B543–B551 (2012).
[Crossref] [PubMed]

W. Shieh, H. Bao, and Y. Tang, “Coherent optical OFDM: theory and design,” Opt. Express 16(2), 841–859 (2008).
[Crossref] [PubMed]

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]

R. Schmogrow, M. Winter, D. Hillerkuss, B. Nebendahl, S. Ben-Ezra, J. Meyer, M. Dreschmann, M. Huebner, J. Becker, C. Koos, W. Freude, and J. Leuthold, “Real-time OFDM transmitter beyond 100 Gbit/s,” Opt. Express 19(13), 12740–12749 (2011).
[Crossref] [PubMed]

R. Bouziane, R. Schmogrow, D. Hillerkuss, P. A. Milder, C. Koos, W. Freude, J. Leuthold, P. Bayvel, and R. I. Killey, “Generation and transmission of 85.4 Gb/s real-time 16QAM coherent optical OFDM signals over 400 km SSMF with preamble-less reception,” Opt. Express 20(19), 21612–21617 (2012).
[Crossref] [PubMed]

B. Inan, S. Adhikari, O. Karakaya, P. Kainzmaier, M. Mocker, H. von Kirchbauer, N. Hanik, and S. L. Jansen, “Real-time 93.8-Gb/s polarization-multiplexed OFDM transmitter with 1024-point IFFT,” Opt. Express 19(26), B64–B68 (2011).
[Crossref] [PubMed]

Trans. Am. Inst. Electr. Eng. (1)

H. Nyquist, “Certain topics in telegraph transmission theory,” Trans. Am. Inst. Electr. Eng. 47(2), 617–644 (1928).
[Crossref]

Other (6)

M. Yoshida, T. Omiya, K. Kasai, and M. Nakazawa, “Real-time FPGA-based coherent optical receiver for 1 Gsymbol/s, 64 QAM transmission,” in Optical Fiber Communication Conference, OSA Technical Digest (CD) (Optical Society of America, 2011), paper OTuN3.
[Crossref]

D. Qian, T. Kwok, N. Cvijetic, J. Hu, and T. Wang, “41.25 Gb/s real-time OFDM receiver for variable rate WDM-OFDMA-PON transmission,” in Optical Fiber Communication Conference, OSA Technical Digest (CD) (Optical Society of America, 2010), paper PDPD9.
[Crossref]

A. Nespola, S. Straullu, G. Bosco, A. Carena, and P. Yanchao Jiang, Poggiolini, F. Forghieri, Y. Yamamoto, M. Hirano, T. Sasaki, J. Bauwelinck, and K. Verheyen, “1306-km 20×124.8-Gb/s PM-64QAM transmission over PSCF with net SEDP 11,300 (bkm)/s/Hz using 1.15 samp/symb DAC,” in 39th European Conference and Exhibition on Optical Communication (ECOC2013), paper Th.2.D.1.

S. Smith, The Scientist & Engineer's Guide to Digital Signal Processing, (California Technical Pub., 1997), p. 45, http://www.dspguide.com/ .

R. Schmogrow, M. Meyer, S. Wolf, B. Nebendahl, D. Hillerkuss, B. Baeuerle, M. Dreschmann, J. Meyer, M. Huebner, J. Becker, C. Koos, W. Freude, and J. Leuthold, “150 Gbit/s Real-time Nyquist pulse transmission over 150 km SSMF enhanced by DSP with dynamic precision,” in Optical Fiber Communication Conference, OSA Technical Digest (Optical Society of America, 2012), paper OM2A.6.
[Crossref]

R. Schmogrow, M. Meyer, P. C. Schindler, A. Josten, S. Ben-Ezra, C. Koos, W. Freude, and J. Leuthold, “252 Gbit/s real-time Nyquist pulse generation by reducing the oversampling factor to 1.33,” in Optical Fiber Communication Conference, OSA Technical Digest (Optical Society of America, 2013), paper OTu2I.1.
[Crossref]

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Figures (12)

Fig. 1
Fig. 1 Vision of a flexgrid optical network, where various Tx generate signals with adjustable bandwidths. In this example, the middle channel Tx (at frequency f1) adapts its signal bandwidth flexibly. In Scenario A, Tx 1 generates signals with small bandwidth as its neighboring Tx 0 and Tx 2 (f0 and f2) occupy large bandwidths. In Scenario B, Tx 1 may use more bandwidth as its neighbors occupy small bandwidths. To realize networks with channels of flexible bandwidths, advanced algorithms for Tx and Rx digital signal processing (DSP) need to be found especially as the hardware does not support changing clock frequencies.
Fig. 2
Fig. 2 Spectra of Nyquist and OFDM signals with oversampling factors q = 1 (no oversampling), q = 2 and q = 4 / 3. The main spectra are centered on zero frequency. Image spectra are displayed in light color at multiples of the sampling frequency fs. These spectra are removed by analog filters (schematic transfer function indicated by dashed lines). (a) Spectrum of a Nyquist signal without oversampling. (b) OFDM spectrum (q = 1). (c) Electrical spectrum of a Nyquist signal (q = 2). The spectral guard band (GB) equals the electrical signal bandwidth. (d) OFDM spectrum (q = 2). (e) Nyquist spectrum with reduced oversampling factor q = 4 / 3. For a fixed sampling frequency fs the symbol rate is increased while the GB is reduced. (f) Corresponding OFDM spectrum for q = 4 / 3.
Fig. 3
Fig. 3 DSP with dynamical increase of the computational word length. (a) An elementary sinc-impulse with amplitude 1 at t = 0 is scaled, multiplied with factors 2s, and rounded to a signed 6 bit integer. The weight s is chosen according to the magnitude decrease of the sinc-function. (b) An output waveform resulting from the superposition of various sinc-impulses. Samples (see green-framed blow-up) for each point of time are added. (c) Adder tree for groups with different s uses either multiplications ( × , more accurate) or divisions ( ÷ ) to merge the groups.
Fig. 4
Fig. 4 Nyquist signaling with rational oversampling factor q = k / l = 4 / 3. The sampling period ts is a fraction of Ts. (a) At the Tx, only every l-th sample is considered (open circles, dashed grid) instead of computing k samples per symbol (dotted grid). The IR is sampled at different relative sampling positions which repeat after l = 3 pulses (black, red, and blue). (b) Output waveform at the Tx. (c) At the Rx, the sampled signal (open circles) is interpolated with sinc-functions to recover the transmitted data. This time, only every k-th sample needs to be processed (open squares, red grid-lines). A number of k = 4 differently sampled sinc-functions (black, red, blue, and green) need to be provided as IR of the Rx filter. (d) Waveform after resampling. Data is recovered ISI-free (open squares).
Fig. 5
Fig. 5 Rx filter if neighboring channels are not fully removed by analog filters. (a) An ADC samples the analog signal with 1.33 samples per symbol (SPS). The spectrum shows fragments of the neighbors (red). Upsampling results in periodic repetitions. The interpolation filter (rect(f), blue dotted line) removes the periodic repetitions, but not the neighboring fragments (red). To avoid crosstalk during downsampling, these fragments have to be removed by an additional filter (H(f), red dotted line). Both filters can be combined and replaced by rect(f) H(f) = H(f). (b) Combined Rx resampling and filtering by using the same technique as described by Fig. 4(c). (c) Waveform after combined resampling and filtering results in the same signal as in Fig. 4(d).
Fig. 6
Fig. 6 Impulse response generator. A copy of the input sample is multiplied by each of the filter coefficients h[r] representing the sampled IR of the filter with order R and R + 1 filter coefficients. The multiplication with h[r] leads to a finite number of products x[m] h[r] that can be stored in look-up tables (LUT) thereby avoiding resource-hungry multiplications.
Fig. 7
Fig. 7 Parallel FIR filter design where N = 4 input samples x[m] are processed within each clock cycle (clk, left vertical time axis t) to produce four output samples y[m] with the summation y[m] = ∑x[mr] h[r], Eq. (2). Each input sample is multiplied with the filter impulse response (IR) h[r] using the IR generators described in Fig. 6. In this example, the filter response is represented by R + 1 = 8 filter coefficients. In order to prepare the computation of the filter output y[m], the pulses are arranged within a two-dimensional (2D) array (right, flipped upside down and rotated counter-clockwise by 90°) with each IR at time m being delayed by one sample with respect to the previous IR at m − 1. The output y[m] is then obtained by summing all samples that are located in the same row of the 2D array.
Fig. 8
Fig. 8 Flexible adaptation of the symbol rate and bandwidth through changing the oversampling factor q while keeping the sampling rate fs constant. For clarity, only clock cycle 0 according to Fig. 7 is shown. (a) Clock cycle 0 of Fig. 7 is reproduced, q = 1 (b) For an oversampling factor q = 2 every other IR generator must produce zeros as impulse response, thereby reducing the data rate by a factor of 2. (c) To generate signals with q = 4, three of the 4 pulses processed in parallel are set to zero. (d) A rational oversampling factor such as q = 4 / 3 can be realized by adjusting the IR generator coefficients hA, B, C according to Fig. 4(a).
Fig. 9
Fig. 9 Ensemble-averaged power spectra obtained from VHDL simulations as a function of frequency normalized to the sampling rate fs. All Nyquist signals are generated with the same FIR filter structure of order R = 64. (a) Spectrum for a signal oversampling of q = 4. The signal bandwidth is fs / 4. (b) Spectrum for an oversampling q = 2. The signal bandwidth is fs / 2. (c) Spectrum for an oversampling q = 4 / 3. The signal bandwidth is fs / (4 / 3).
Fig. 10
Fig. 10 Experimental setup for real-time Nyquist sinc-pulse shaping. The Tx comprises two synchronized FPGAs, two DACs, optional image rejection filters, and an optical I/Q-modulator. Data are encoded on an ECL at 1550 nm. For transmission experiments (switch position 1): EDFA 1 and PDM emulation followed by either up to four 75 km spans of SSMF and EDFAs (for the evaluation of the dynamic computational precision) or by 100 km ULAF (for evaluation of q = 4 / 3 oversampled PDM-64QAM transmission). Signals are recovered with a coherent receiver (EDFA 2 and Agilent OMA). For QPSK and 16QAM measurements with oversampling factor q = 4 / 3 only, switch position 2 bypasses the link. The OSNR is adjusted by varying the input power to EDFA 2. In this case, we keep the OMA at optimum input power with a gain-controlled EDFA 3.
Fig. 11
Fig. 11 Experimental results for Nyquist shaped PDM-16QAM (14 GBd) and PDM-64QAM (12.5 GBd) transmitted over various spans of SSMF. (a) Measured (black) and simulated (white) spectra for 16QAM signals. The spectral noise floor is due to quantization noise, and can be removed by analog low-pass filters. (b) Measured BER of both modulation formats and fiber spans for standard and dynamically adjusted DSP word lengths as described in Fig. 3(c). As expected, the ( × )-design shows best performance.
Fig. 12
Fig. 12 Experimental results for real-time Nyquist pulse shaping with filter order R = 32. (a) 21 GBd 16QAM spectra measured with low pass filters (LPF) used for image rejection (black) and without (red). (b) – (d) BER (squares) and BER estimated from measured EVM (lines) as a function of OSNR for QPSK and 16QAM with (black) and without (red) image rejection filters. (e) Constellation diagrams obtained back-to-back for a single polarization (SP, red) and for PDM-64QAM after transmission over 100 km (blue).

Tables (2)

Tables Icon

Table 1 FPGA Resource Utilization for FIR Filters of Different Orders R and Impulse Response Duration T

Tables Icon

Table 2 FPGA Resource Utilization for FIR Filters with and without Dynamically Adjusted DSP Word Length

Equations (2)

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symbolrate F s = samplingrate f s oversamplingfactorq .
y[ m ]= r=R/2 +R/2 x[ mr ]h[ r ] ,m,rZ.

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