Abstract

A novel, optical temporal encoding/decoding method is proposed and demonstrated. This can be accomplished by passing a short optical pulse through cascaded long-period fiber gratings. It has the advantages of constructing ultrafast codes and developing resistance to interferometric perturbations among the coded pulses. To verify the feasibility as a code generator, two types of codes are generated and compared with the predicted code patterns. In addition, to show an application for an optical code-division-multiplexing system, decoding performances with matched and unmatched decoders are compared.

© 2003 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |

  1. P. R. Prucnal, M. A. Santoro, and T. R. Fan, �??Spread spectrum fiber-optic local area network using optical processing,�?? J. Lightwave Technol. 4, 547-554 (1986).
    [CrossRef]
  2. J. A. Salehi, �??Code division multiple-access techniques in optical fiber networks-Part I: Fundamental principles,�?? IEEE Trans. Commun. 37, 824-833 (1989).
    [CrossRef]
  3. M. Murata and K.-I. Kitayama, �??Ultrafast photonic label switch for asynchronous packets of variable length,�?? Proc. IEEE, INFOCOM 2002, 1, 371-380 (2002).
  4. E. Marom, �??Optical delay line matched filters,�?? IEEE Trans. Circuits Syst. CAS-25, 360-364 (1978).
    [CrossRef]
  5. G.-C. Yang and W. C. Kwong, Prime Code with Applications to CDMA Optical and Wireless Networks (Artech House, Boston, MA, 2002).
  6. A. S. Holmes and R. R. A. Syms, �??All-optical CDMA using Quasi-prime codes,�?? J. Lightwave Technol. 10, 279- 286 (1992).
    [CrossRef]
  7. G. E. Town, K. Chan, and G. Yoffe, �??Design and performance of high-speed optical pulse-code generators using optical fiber Bragg gratings,�?? IEEE J. Sel. Top. Quantum Electron. 5, 1325-1331 (1999).
    [CrossRef]
  8. P. Petropoulos, N. Wada, P. C. Teh, M. Ibsen, W. Chujo, K.-I. Kitayama, and D. J. Richardson, �??Demonstration of a 64-chip OCDMA system using superstructured fiber gratings and time-gating detection,�?? IEEE Photon. Technol. Lett. 13, 1239�??1241 (2001).
    [CrossRef]
  9. B. H. Lee and J. Nishii, �??Dependence of fringe spacing on the grating separation in a long-period fiber grating pair,�?? Appl. Opt. 38, 3450-3459 (1999).
    [CrossRef]
  10. T. J. Eom, N. H. Seong, D. Y. Kim, C. S Park, U.-C. Paek, and B. H. Lee, �??OTDM signal generation using a long-period fiber grating pair,�?? Proc. Optoelectronics and Communications (OECC/IOOC �??2001) Conf., Sydney, Australia, 117-118 (2001).
  11. S. Choi, T. J. Eom, J. W. Yu, B. H. Lee, and K. Oh, �??Novel all-fiber bandpass filter based on hollow optical fiber,�?? IEEE Photon. Technol. Lett. 14, 1701-1703 (2002).
    [CrossRef]
  12. B. H. Lee and J. Nishii, "Bending sensitivity of in-series long-period fiber gratings," Opt. Lett. 23, 1624- 1626 (1998).
    [CrossRef]
  13. B. H. Lee, T.-J. Eom, M. J. Kim, U.-C. Paek, and T. Park, "Mode coupling within inner cladding fibers," J. Opt. Soc. Korea 7, 53-58 (2003).
    [CrossRef]
  14. S. Ramachandran, "Dispersion management with higher order mode fibers," Proc. Optoelectronics and Communications (OECC �??2003) Conf., Shanghai, China, 573-574 (2003).
  15. L. R. Chen, �??Flexible fiber Bragg grating encoder/decoder for hybrid wavelength-time optical CDMA,�?? IEEE Photon. Technol. Lett. 13, 1233 �??1235 (2001
    [CrossRef]

Appl. Opt.

IEEE J. Sel. Top. Quantum Electron

G. E. Town, K. Chan, and G. Yoffe, �??Design and performance of high-speed optical pulse-code generators using optical fiber Bragg gratings,�?? IEEE J. Sel. Top. Quantum Electron. 5, 1325-1331 (1999).
[CrossRef]

IEEE Photon. Technol. Lett.

P. Petropoulos, N. Wada, P. C. Teh, M. Ibsen, W. Chujo, K.-I. Kitayama, and D. J. Richardson, �??Demonstration of a 64-chip OCDMA system using superstructured fiber gratings and time-gating detection,�?? IEEE Photon. Technol. Lett. 13, 1239�??1241 (2001).
[CrossRef]

S. Choi, T. J. Eom, J. W. Yu, B. H. Lee, and K. Oh, �??Novel all-fiber bandpass filter based on hollow optical fiber,�?? IEEE Photon. Technol. Lett. 14, 1701-1703 (2002).
[CrossRef]

L. R. Chen, �??Flexible fiber Bragg grating encoder/decoder for hybrid wavelength-time optical CDMA,�?? IEEE Photon. Technol. Lett. 13, 1233 �??1235 (2001
[CrossRef]

IEEE Trans. Circuits Syst.

E. Marom, �??Optical delay line matched filters,�?? IEEE Trans. Circuits Syst. CAS-25, 360-364 (1978).
[CrossRef]

IEEE Trans. Commun.

J. A. Salehi, �??Code division multiple-access techniques in optical fiber networks-Part I: Fundamental principles,�?? IEEE Trans. Commun. 37, 824-833 (1989).
[CrossRef]

J. Lightwave Technol

P. R. Prucnal, M. A. Santoro, and T. R. Fan, �??Spread spectrum fiber-optic local area network using optical processing,�?? J. Lightwave Technol. 4, 547-554 (1986).
[CrossRef]

J. Lightwave Technol.

A. S. Holmes and R. R. A. Syms, �??All-optical CDMA using Quasi-prime codes,�?? J. Lightwave Technol. 10, 279- 286 (1992).
[CrossRef]

J. Opt. Soc. Korea

Opt. Lett.

Optoelectronics and Communications

S. Ramachandran, "Dispersion management with higher order mode fibers," Proc. Optoelectronics and Communications (OECC �??2003) Conf., Shanghai, China, 573-574 (2003).

Proc. IEEE, INFOCOM 2002

M. Murata and K.-I. Kitayama, �??Ultrafast photonic label switch for asynchronous packets of variable length,�?? Proc. IEEE, INFOCOM 2002, 1, 371-380 (2002).

Proc. Optoelectronics and Communications

T. J. Eom, N. H. Seong, D. Y. Kim, C. S Park, U.-C. Paek, and B. H. Lee, �??OTDM signal generation using a long-period fiber grating pair,�?? Proc. Optoelectronics and Communications (OECC/IOOC �??2001) Conf., Sydney, Australia, 117-118 (2001).

Other

G.-C. Yang and W. C. Kwong, Prime Code with Applications to CDMA Optical and Wireless Networks (Artech House, Boston, MA, 2002).

Cited By

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

Alert me when this article is cited.


Figures (5)

Fig. 1.
Fig. 1.

Schematic diagram of a temporal encoder using cascaded LPGs. Inset figures are the measured near-field patterns of the core mode and the cladding mode.

Fig. 2.
Fig. 2.

The configurations and temporal responses of cascaded LPGs for two codes: C1 and C2.; (a) Structure of cascaded LPGs with C1; (b) Predicted response of cascaded LPGs with C1; (c) Measured response of cascaded LPGs with C1; (d) Structure of cascaded LPGs with C2; (e) Predicted response of cascaded LPGs with C2 (f) Measured response of cascaded LPGs with C2

Fig. 3.
Fig. 3.

Transmission spectra of two cascaded LPGs with (a) C1 (b) C2. Inset figures are the predicted spectra.

Fig. 4.
Fig. 4.

Experimental set-up. The first LPGs encode an input short pulse into C1, which is decoded by two cascaded LPGs with C1 (autocorrelation) and C2 (cross-correlation). EDFA is an erbium-doped fiber amplifier.

Fig. 5.
Fig. 5.

Decoded signals obtained with (a) the matched decoder; C1*C1 (b) the unmatched decoder; C1*C2. Dotted line: predicted, solid line: measured. Inset figures are the predicted pulse trains measured after the decoder, but before the autocorrelator.

Equations (2)

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

( β co β cl ) = 2 π Λ
Δ T = L c Δ m eff

Metrics