Skip to main content
SpringerLink
Log in

Digital signal processing techniques in Nyquist-WDM transmission systems

  • Published:
Photonic Network Communications Aims and scope Submit manuscript

Abstract

In single-carrier wavelength-division multiplexing (WDM) systems, the spectral efficiency can be increased by reducing the channel spacing through digital signal processing (DSP). Two major issues with using tight filtering are cross talk between channels and inter-symbol interference (ISI) within a channel. By fulfilling the Nyquist criterion, Nyquist spectral-shaped WDM systems can achieve narrow channel spacings close to the symbol rate \((\hbox {R}_{\mathrm{S}})\) with negligible cross talk and ISI. In principle, DSP can generate any signals with arbitrary waveforms and spectrum shapes. However, the complexity of DSP is limited by its cost and power consumption. It is necessary to optimize the DSP to achieve the required performance at a minimum complexity. In this paper, we first introduced the background of digital signal processing for Nyquist spectral shaping in optical fiber WDM systems. Then, we investigated the use of digital finite impulse response (FIR) filters to generate Nyquist-WDM 16-ary quadrature amplitude modulation (16QAM) signals with the raised-cosine (RC) and root-raised-cosine (RRC) shape spectra. The system performance of both the RC and RRC spectra is also examined. Moreover, we explored the various methods to reduce digital-to-analog converter (DAC) sampling speed, such as using super-Gaussian electrical filters (E-filter) and spectral pre-emphasis. We also discussed receiver-side matched filter design for Nyquist-WDM receiver optimization.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12
Fig. 13
Fig. 14
Fig. 15
Fig. 16
Fig. 17

Similar content being viewed by others

References

  1. Li, G.: Recent advances in coherent optical communication. Adv. Opt. Photon. 1, 279–307 (2009)

    Article  Google Scholar 

  2. Tkach, R.W.: Scaling optical communications for the next decade and beyond. Bell Labs Tech. J. 14(4), 3–9 (2010)

    Article  Google Scholar 

  3. Shieh, W., Bao, H., Tang, Y.: Coherent optical OFDM: theory and design. Opt. Express 16(2), 841–859 (2008)

    Article  Google Scholar 

  4. Soto, M.A., Alem, M., Shoaie, M.A., Vedadi, A., Brès, C.-S., Thévenaz, L., Schneider, T.: Optical sinc-shaped Nyquist pulses of exceptional quality. Nat. Commun. 4, 3898–3908 (2013)

    Article  Google Scholar 

  5. Liu, X., Chandrasekhar, S., Zhu, B., Winzer, P.J., Gnauck, A.H., Peckham, D.W.: Transmission of a 448-Gb/s reduced-guard-interval CO-OFDM signal with a 60-GHz optical bandwidth over 2000 km of ULAF and five 80-GHz-Grid ROADMs. In: Proc. OFC/NFOEC, paper PDPC2 (2010)

  6. Proakis, J.G.: Digital Communications, Chap. 9, 4th edn. McGGraw-Hill, New York (2001)

    Google Scholar 

  7. Cartledge, J.C., Downie, J.D., Hurley, J.E., Karar, A.S., Jiang, Y., Roberts, K.: Pulse shaping for 112 Gbit/s polarization multiplexed 16-QAM signals using a 21 Gsa/s DAC. Opt. Express 19(26), B628–B635 (2011)

    Article  Google Scholar 

  8. Cai, J.-X.: 100G transmission over transoceanic distance with high spectral efficiency and large capacity. J. Lightw. Technol. 30(24), 3845–3856 (2012)

    Article  Google Scholar 

  9. Fickers, J., Ghazisaeidi, A., Salsi, M., Charlet, G., Horlin, F., Emplit, P., Bigo, S.: Design Rules for Pulse Shaping in PDM-QPSK and PDM-16QAM Nyquist-WDM Coherent Optical Transmission Systems. In: Proc. ECOC, 2012, paper We.1.C.2 (2012)

  10. Xie, C., Raybon, G., Winzer, P.J.: Hybrid 224-Gb/s and 112-Gb/s PDM-QPSK transmission at 50-GHz channel spacing over 1200-km dispersion-managed LEAF spans and 3 ROADMs. In: Proc. OFC/NFOEC, 2011, paper PDPD2 (2011)

  11. Rafique, D., Napoli, A., Calabro, S., Spinnler, B.: Digital preemphasis in optical communication systems: on the DAC requirements for terabit transmission applications. J. Lightw. Technol. 32(19), 3247–3256 (2014)

    Article  Google Scholar 

  12. Zhou, X., Nelson, L., Issac, R., Magill, P., Zhu, B., Peckham, D.: 1200km Transmission of 50GHz spaced, 5\(\times \)504-Gb/s PDM-32-64 hybrid QAM using Electrical and Optical Spectral Shaping. In: Proc. OFC/NFOEC, 2012, paper OM2A.2 (2012)

  13. Randel, S., Pilori, D., Corteselli, S., Raybon, G., Adamiecki, A., Gnauck, A., Chandrasekhar, S., Winzer, P., Altenhain, L., Bielik, A., Schmid, R.: All-Electronic Flexibly Programmable 864-Gb/s Single-Carrier PMD-64-QAM. In: Proc. OFC/NFOEC, 2014, paper Th5C.8 (2014)

  14. Cai, J.-X., Cai, Y., Davidson, C.R., Foursa, D.G., Lucero, A., Sinkin, O., Patterson, W., Pilipetskii, A., Mohs, G., Bergano, N.S.: Transmission of 96\(\times \)100G pre-filtered PDM-RZ-QPSK channels with 300 % spectral efficiency over 10,608km and 400 % spectral efficiency over 4368 km. In: Proc. OFC/NFOEC, 2010, paper PDPB10 (2010)

  15. Bosco, G.: Spectral shaping in ultra-dense WDM systems: optical versus electrical approaches. In: Proc. OFC/NFOEC, 2012, paper OM3H.1 (2012)

  16. Pan, J., Isautier, P., Ralph, S.E.: Digital pre-shaping for narrowband filtering impairment compensation in superchannel applications. In: Proc. Optical Sensors, 2013, paper JT3A. 1 (2013)

  17. Mazurczyk, M.: Optical spectral shaping and high spectral efficiency in long haul systems. In: Proc. OFC/NFOEC, 2014, paper Tu3J.4 (2014)

  18. Duthel, T., Raabe, C., Hermann, P., Whiteaway, J.E., Geyer, J.C., Fludger, C.R.S., Kupfer, T.: DAC enabled spectrally efficient CP-QPSK at 28Gbaud. In: Proc. ECOC, 2012, paper Tu.4.A.4, (2012)

  19. Wang, J., Xie, C., Pan, Z.: Optimization of DSP to generate spectrally efficient 16QAM Nyquist-WDM signals. Photon. Technol. Lett. 25(8), 772–775 (2013)

    Article  Google Scholar 

  20. Arik, S.O., Ho, K.-P., Kahn, J.M.: Optical network scaling: roles of spectral and spatial aggregation. Opt. Express 22(24), 29868–29887 (2014)

    Article  Google Scholar 

  21. Wang, J., Xie, C., Pan, Z.: Reducing equalizer complexity in coherent receivers for Nyquist spectrally shaped systems with matched filters. In: Proc. OFC/NFOEC, 2013, paper OTu2I.3 (2013)

  22. Gnauck, A.H., Winzer, P.J., Chandrasekhar, S., Liu, X., Zhu, B., Peckham, D.W.: Spectrally efficient long-haul WDM transmission using 224-Gb/s polarization-multiplexed 16-QAM. J. Lightw. Technol. 29(4), 373–377 (2011)

    Article  Google Scholar 

  23. Winzer, P.J.: Optical networking beyond WDM. IEEE Photon. J. 4(2), 647–651 (2012)

    Article  Google Scholar 

  24. Dutta, A.K.: WDM Technologies: Optical Networks. Elsevier Science, New York (2004)

    Google Scholar 

  25. Yu, J., Zhou, X.: Ultra-high-capacity DWDM transmission system for 100G and beyond. IEEE Commun. Mag. 48, S56–S64 (2010)

    Article  Google Scholar 

  26. Cvijetic, N., Cvijetic, M., Huang, M.-F., Ip, E., Huang, Y.-K., Wang, T.: Terabit optical access networks based on WDM-OFDMA-PON. J. Lightw. Technol. 30(4), 493–503 (2012)

    Article  Google Scholar 

  27. Pan, Z., Wang, J., Weng, Y.: Investigation of digital-to-analog converter (DAC) in digital Nyquist-WDM transmission systems. In: Proc. 8th POEM, paper OT2C.1 (2015)

  28. Mazurczyk, M.: Spectral shaping in long haul optical coherent systems with high spectral efficiency. J. Lightw. Technol. 32(16), 2915–2924 (2014)

    Article  Google Scholar 

  29. Dong, Z., Li, X., Yu, J., Chi, N.: 6\(\times \)144-Gb/s Nyquist-WDM PDM-64QAM generation and transmission on a 12-GHz WDM grid equipped with Nyquist-band pre-equalization. J. Lightw. Technol. 30(23), 3687–3692 (2012)

    Article  Google Scholar 

  30. Glover, I., Grant, P.: Digital Communications, Chap. 2. Pearson Education, New York (2004)

    Google Scholar 

  31. Wang, J., Jiang, X., Weng, Y., He, X., Pan, Z.: Non-data-aided chromatic dispersion estimation for Nyquist spectrally shaped fiber transmission systems. In: Proc. 23rd WOCC, paper O1.1 (2014)

  32. Kikuchi, K.: Clock recovering characteristics of adaptive finite-impulse response filters in digital coherent optical receivers. Opt. Express 19(6), 5611–5619 (2011)

    Article  MathSciNet  Google Scholar 

  33. Weng, Y., Wang, J., Pan, Z.: Comparison of advanced DSP techniques for spectrally efficient Nyquist-WDM signal generation using digital FIR filters at transmitters based on higher-order modulation formats. In: Proc. SPIE 9773, 977304 (2016)

  34. Winzer, P.J.: High-spectral-efficiency optical modulation formats. J. Lightw. Technol. 30(24), 3824–3835 (2012)

    Article  Google Scholar 

  35. Boyd, K.P.: Optical Communication Systems: Fundamentals, Techniques and Applications, Chap. 3. Nova Science, New York (2015)

    Google Scholar 

  36. Reis, J.D., Shahpari, A., Teixeira, A.L.: Performance optimization of Nyquist signaling for spectrally efficient optical access networks. J. Opt. Commun. Netw. 7(2), A200–A208 (2015)

    Article  Google Scholar 

  37. Weng, Y., Wang, J., Pan, Z.: Spectrally Efficient Nyquist-WDM PDM-64QAM Signal Generation using Interleaved DAC with Zero-Order Holding. In: Proc. OFC/NFOEC, paper Th2A.34 (2016)

  38. Rafique, D., Rahman, T., Napoli, A., Spinnler, B.: Digital pre-emphasis in optical communication systems: on the nonlinear performance. J. Lightw. Technol. 33(1), 140–150 (2015)

    Article  Google Scholar 

  39. Winzer, P.J., Pfennigbauer, M., Essiambre, R.-J.: Coherent crosstalk in ultradense WDM systems. J. Lightw. Technol. 23(4), 1734–1744 (2005)

    Article  Google Scholar 

  40. Wang, J., Xie, C., Pan, Z.: Generation of spectrally efficient Nyquist-WDM QPSK signals using digital FIR or FDE filters at transmitters. J. Lightw. Technol. 30(23), 3679–3686 (2012)

    Article  Google Scholar 

  41. Curri, V., Carena, A., Bosco, G., Poggiolini, P., Forghieri, F.: Optimization of DSP-based Nyquist-WDM PM-16QAM transmitter. In: Proc. ECOC, paper Tu.4.A.5 (2012)

  42. Pan, J., Liu, C., Detwiler, T., Stark, A.J., Hsueh, Y.-T., Ralph, S.E.: Inter-channel crosstalk cancellation for Nyquist-WDM superchannel applications. J. Lightw. Technol. 30(24), 3993–3999 (2012)

    Article  Google Scholar 

  43. Rafique, D., Napoli, A., Calabro, S., Spinnler, B.: Digital preemphasis in optical communication systems: on the DAC requirements for terabit transmission applications. J. Lightw. Technol. 32(19), 3247–3256 (2014)

    Article  Google Scholar 

  44. Pan, Z., Wang, J., Weng, Y.: Digital signal processing techniques in Nyquist-WDM transmission system. In: Proc. 14th ICOCN, paper Sa2D.2 (2015)

  45. Xiang, M., Tang, H., Fu, S., Tang, M., Shum, P., Liu, D.: Performance comparison of offset-16QAM and 16QAM for Nyquist WDM superchannel with digital spectral shaping. J. Lightw. Technol. 33(17), 3623–3629 (2015)

    Article  Google Scholar 

  46. Fatadin, I., Ives, D., Savory, S.J.: Blind equalization and carrier phase recovery in a 16-QAM optical coherent system. J. Lightw. Technol. 27(15), 3042–3049 (2009)

    Article  Google Scholar 

  47. Wang, J., Xie, C., Pan, Z.: Matched filter design for RRC spectrally shaped Nyquist-WDM systems. Photon. Technol. Lett. 25(23), 2263–2266 (2013)

    Article  Google Scholar 

  48. Leibrich, J., Rosenkranz, W.: Frequency Domain Equalization with Minimum Complexity in Coherent Optical Transmission Systems. In: Proc. OFC/NFOEC, paper OWV1 (2010)

  49. Zhu, C., Corcoran, B., Tran, A.V., Lowery, A.J.: Nyquist-WDM with low-complexity joint matched filtering and adaptive equalization. Photon. Technol. Lett. 26(23), 2323–2326 (2014)

    Article  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. EECE Department, University of Louisiana at Lafayette, Lafayette, LA, 70504-3890, USA

    Zhongqi Pan & Yi Weng

  2. Qualcomm Technologies Inc., San Diego, CA, 92121, USA

    Junyi Wang

Authors
  1. Zhongqi Pan
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Junyi Wang
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Yi Weng
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Yi Weng.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Pan, Z., Wang, J. & Weng, Y. Digital signal processing techniques in Nyquist-WDM transmission systems. Photon Netw Commun 32, 236–245 (2016). https://doi.org/10.1007/s11107-015-0598-8

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11107-015-0598-8

Keywords

Search

Navigation