Abstract

We investigate carrier synchronization for coherent detection of optical signals encoding 3 and 4 bits/symbol. We consider the effects of laser phase noise and of additive white Gaussian noise (AWGN), which can arise from local oscillator (LO) shot noise or LO-spontaneous beat noise. We identify 8-and 16-ary quadrature amplitude modulation (QAM) schemes that perform well when the receiver phase-locked loop (PLL) tracks the instantaneous signal phase with moderate phase error. We propose implementations of 8-and 16-QAM transmitters using Mach-Zehnder (MZ) modulators. We outline a numerical method for computing the bit error rate (BER) of 8-and 16-QAM in the presence of AWGN and phase error. It is found that these schemes can tolerate phase-error standard deviations of 2.48° and 1.24°, respectively, for a power penalty of 0.5 dB at a BER of 10-9. We propose a suitable PLL design and analyze its performance, taking account of laser phase noise, AWGN, and propagation delay within the PLL. Our analysis shows that the phase error depends on the constellation penalty, which is the mean power of constellation symbols times the mean inverse power. We establish a procedure for finding the optimal PLL natural frequency, and determine tolerable laser linewidths and PLL propagation delays. For zero propagation delay, 8-and 16-QAM can tolerate linewidth-to-bit-rate ratios of 1.8 × 10-5 and 1.4 × 10-6, respectively, assuming a total penalty of 1.0 dB.

© 2005 IEEE

PDF Article

References

  • View by:
  • |

  1. J. M. Kahn and K.-P. Ho, "Spectral efficiency limits and modulation/detection techniques for DWDM systems", IEEE J. Sel. Topics Quantum Electron., vol. 10, no. 2, pp. 259-272, Mar./Apr. 2004.
  2. R. A. Griffin and A. C. Carter, "Optical differential quadrature phase-shift keying (oDQPSK) for high-capacity optical transmission", in Proc. Optical Fiber Communication Conf., Anaheim, CA, 2002,Paper WX6,. pp. 367-368.
  3. M. Ohm, "Optical 8-DPSK and receiver with direct detection and multilevel electrical signals", in Proc. IEEE/LEOS Workshop Advanced Modulation Formats, San Francisco, CA, Jul. 2004, pp. 45-46.
  4. P. P. Mitra and J. B. Stark, "Nonlinear limits to the information capacity of optical fibre communications", Nature, vol. 411, no. 6841, pp. 1027-1030, Jun. 2001.
  5. J. P. Gordon and L. F. Mollenauer, "Phase noise in photonic communications systems using linear amplifiers", Opt. Lett., vol. 15, no. 23, pp. 1351-1353, Dec. 1990.
  6. S. Norimatsu and K. Iwashita, "Linewidth requirements for optical synchronous detection systems with nonnegligible loop delay time", J. Lightw. Technol., vol. 10, no. 3, pp. 341-349, Mar. 1992.
  7. J. R. Barry and J. M. Kahn, "Carrier synchronization for homodyne and heterodyne detection of optical quadriphase-shift keying", J. Lightw. Technol., vol. 10, no. 12, pp. 1939-1951, Dec. 1992.
  8. G. J. Foschini, R. D. Gitlin and S. B. Weinstein, "On the selection of a two-dimensional signal constellation in the presence of phase jitter and Gaussian noise", Bell Syst. Tech. J., vol. 52, pp. 927-965, Jul./Aug. 1973.
  9. K. P. Ho, "Generation of arbitrary quadrature-amplitude modulation signals using a single dual-drive modulator", in Proc. IEEE/LEOS Workshop Advanced Modulation Formats, San Francisco, CA, Jul. 2004, pp. 11-12.
  10. V. K. Prabhu, "PSK performance with imperfect carrier phase recovery", IEEE Trans. Aerosp. Electron. Syst., vol. AES-12, no. 2, pp. 275-285, Mar. 1976.
  11. J. G. Proakis, Digital Communications, 4th ed. New York: McGraw-Hill, 2000.
  12. B. F. Jorgensen, B. Mikkelsen and C. J. Mahon, "Analysis of optical amplifier noise in coherent optical communication systems with optical image rejection receivers", J. Lightw. Technol., vol. 10, no. 5, pp. 660-671, May 1992.
  13. D.-S. Ly-Gagnon, K. Katoh and K. Kikuchi, "Unrepeatered optical transmission of 20 Gb/s quadrature phase-shift keying signals over 210 km using homodyne phase-diversity receiver and digital signal processing", Electron. Lett., vol. 41, no. 4, pp. 206-207, Feb. 2005.
  14. D.-S. Ly-Gagnon, K. Katoh and K. Kikuchi, "Coherent demodulation of differential 8-phase-shift keying with optical phase diversity and digital signal processing", in Proc. 17th Annu. Meeting IEEE Lasers and Electro-Optics Society (LEOS), vol. 2, Rio Grande, PR, Nov. 2004, pp. 607-608.
  15. G. P. Agrawal, Fiber Optic Communication System, 3rd ed. New York: Wiley, 2002.
  16. M. A. Grant, W. C. Michie and M. J. Fletcher, "The performance of optical phase-locked loops in the presence of nonnegligible loop propagation delay", J. Lightw. Technol., vol. LT-5, no. 4, pp. 592-597, Apr. 1987.
  17. E. Ip, J. M. Kahn, D. Anthon and J. Hutchins, "Linewidth measurements of MEMS-based tunable lasers for phase-locking applications", IEEE Photon. Technol. Lett., vol. 17, no. 10, pp. 2029-2031, Oct. 2004.

Other (17)

J. M. Kahn and K.-P. Ho, "Spectral efficiency limits and modulation/detection techniques for DWDM systems", IEEE J. Sel. Topics Quantum Electron., vol. 10, no. 2, pp. 259-272, Mar./Apr. 2004.

R. A. Griffin and A. C. Carter, "Optical differential quadrature phase-shift keying (oDQPSK) for high-capacity optical transmission", in Proc. Optical Fiber Communication Conf., Anaheim, CA, 2002,Paper WX6,. pp. 367-368.

M. Ohm, "Optical 8-DPSK and receiver with direct detection and multilevel electrical signals", in Proc. IEEE/LEOS Workshop Advanced Modulation Formats, San Francisco, CA, Jul. 2004, pp. 45-46.

P. P. Mitra and J. B. Stark, "Nonlinear limits to the information capacity of optical fibre communications", Nature, vol. 411, no. 6841, pp. 1027-1030, Jun. 2001.

J. P. Gordon and L. F. Mollenauer, "Phase noise in photonic communications systems using linear amplifiers", Opt. Lett., vol. 15, no. 23, pp. 1351-1353, Dec. 1990.

S. Norimatsu and K. Iwashita, "Linewidth requirements for optical synchronous detection systems with nonnegligible loop delay time", J. Lightw. Technol., vol. 10, no. 3, pp. 341-349, Mar. 1992.

J. R. Barry and J. M. Kahn, "Carrier synchronization for homodyne and heterodyne detection of optical quadriphase-shift keying", J. Lightw. Technol., vol. 10, no. 12, pp. 1939-1951, Dec. 1992.

G. J. Foschini, R. D. Gitlin and S. B. Weinstein, "On the selection of a two-dimensional signal constellation in the presence of phase jitter and Gaussian noise", Bell Syst. Tech. J., vol. 52, pp. 927-965, Jul./Aug. 1973.

K. P. Ho, "Generation of arbitrary quadrature-amplitude modulation signals using a single dual-drive modulator", in Proc. IEEE/LEOS Workshop Advanced Modulation Formats, San Francisco, CA, Jul. 2004, pp. 11-12.

V. K. Prabhu, "PSK performance with imperfect carrier phase recovery", IEEE Trans. Aerosp. Electron. Syst., vol. AES-12, no. 2, pp. 275-285, Mar. 1976.

J. G. Proakis, Digital Communications, 4th ed. New York: McGraw-Hill, 2000.

B. F. Jorgensen, B. Mikkelsen and C. J. Mahon, "Analysis of optical amplifier noise in coherent optical communication systems with optical image rejection receivers", J. Lightw. Technol., vol. 10, no. 5, pp. 660-671, May 1992.

D.-S. Ly-Gagnon, K. Katoh and K. Kikuchi, "Unrepeatered optical transmission of 20 Gb/s quadrature phase-shift keying signals over 210 km using homodyne phase-diversity receiver and digital signal processing", Electron. Lett., vol. 41, no. 4, pp. 206-207, Feb. 2005.

D.-S. Ly-Gagnon, K. Katoh and K. Kikuchi, "Coherent demodulation of differential 8-phase-shift keying with optical phase diversity and digital signal processing", in Proc. 17th Annu. Meeting IEEE Lasers and Electro-Optics Society (LEOS), vol. 2, Rio Grande, PR, Nov. 2004, pp. 607-608.

G. P. Agrawal, Fiber Optic Communication System, 3rd ed. New York: Wiley, 2002.

M. A. Grant, W. C. Michie and M. J. Fletcher, "The performance of optical phase-locked loops in the presence of nonnegligible loop propagation delay", J. Lightw. Technol., vol. LT-5, no. 4, pp. 592-597, Apr. 1987.

E. Ip, J. M. Kahn, D. Anthon and J. Hutchins, "Linewidth measurements of MEMS-based tunable lasers for phase-locking applications", IEEE Photon. Technol. Lett., vol. 17, no. 10, pp. 2029-2031, Oct. 2004.

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.