Experiment on Optical Code-Division-Multiple-Access Switch System Using Spectral Amplitude Encoding of Light-Emitting Diodes

  • Lucie Adam
  • Eli Simova
  • Mohsen Kavehrad


Significant research is directed toward developing fiber-optic local distribution networks providing high data rate transmission in the local end of the backbone network. Code-Division Multiple-Access (CDMA) technique is capable of utilizing the optical channel bandwidth to provide simultaneous asynchronous access. Time-encoded optical CDMA systems can be classified according to the type of encoding, coherent or incoherent. Incoherent time-domain CDMA has advantages of direct detection and low-cost low-coherence optical sources1–3. Coherent time-domain encoding is more difficult to implement4. Such systems with low-coherence sources have also been proposed5. For time-encoded CDMA, the code length increases with the number of users and spectrum broadening occurs. To overcome the drawbacks of time-encoded CDMA, frequency-encoded systems have emerged based on coherent phase coding of ultrashort pulses6. Users operate at data rates compatible with the electronics, but high-cost mode-locked lasers are required. An optical CDMA system based on incoherent amplitude encoding of low-cost light-emitting diodes (LEDs) and direct-detection receivers has been proposed by D. Zaccarin and M. Kavehrad7–8. A comprehensive overview of the optical CDMA systems has been introduced by K. Iversen9.


CDMA System Optical Code Division Multiple Access Optical Transfer Function Spatial Frequency Domain High Data Rate Transmission 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    R. Petrovic, and S. Holmes, CDMA techniques in optical fiber LANs, J. Opt. Comm. 12:101 (1991).Google Scholar
  2. 2.
    J. Salehi, Code division multiple-access techniques in optical fiber networks — part I: fundamental principles, IEEE Trans, on Comm. 37:824 (1989).CrossRefGoogle Scholar
  3. 3.
    J. Salehi, C. Brackett, Code division multiple-access techniques in optical fiber networks — part II: systems performance analysis, IEEE Trans, on Comm. 37:854 (1989).Google Scholar
  4. 4.
    S. Benedetto, G. Olmo, Performance evaluation of coherent optical code division multiple access, Electr. Lett. 27: 2000 (1991).CrossRefGoogle Scholar
  5. 5.
    M. Marhic, Y. Chang, Pulse coding and coherent decoding in fiber-optic ladder networks, Electron. Lett. 25:1535 (1989).CrossRefGoogle Scholar
  6. 6.
    A. Weiner, J. Salehi, J. Heritage, M. Stern, Encoding and decoding of femtosecond pulse for code-division-multiple access, Proc. OSA Top. Meet. Phot. Switch. 3:263 (1989).Google Scholar
  7. 7.
    D. Zaccarin and M. Kavehrad, An optical CDMA system based on spectral amplitude encoding of LED, Phot. Techn.. Lett. 4:479 (1993).CrossRefGoogle Scholar
  8. 8.
    M. Kavehrad and D. Zaccarin, Optical code-division-multiplexed systems based on spectral encoding of noncoherent sources, J. Lightw. Techn. 13:534 (1995).CrossRefGoogle Scholar
  9. 9.
    K. Iversen and D. Hampicke, Comparison and classification of all-optical CDMA systems for future telecommunication networks, Photonics East’95, Proc. SPIE 2614:110.Google Scholar
  10. 10.
    L. Adam, E. Simova, M. Kavehrad, Experimental optical CDMA system based on spectral amplitude encoding of noncoherent broadband sources, Photonics East’95, Proc. SPIE 2614:122.Google Scholar
  11. 11.
    J. W. Goodman, Introduction to Fourier Optics, 2nd ed., McGraw Hill, NY, 1985.Google Scholar
  12. 12.
    D. Sarwate and M. Pursley, Crosscorrelation properties of pseudorandom and related sequences, Proc. IEEE 68:5 (1980).Google Scholar
  13. 13.
    P. Neusy, M. Kavehrad, Proposal for an all-optical code-division multiple access for local area networks, Electr. Lett. 26:1471 (1990).CrossRefGoogle Scholar
  14. 14.
    F. Khaleghi, M. Kavehrad, New correlator receiver architecture for optical CDMA networks with an increased system capacity, Proc. IEEE GLOBECOM, Singapore, 1995.Google Scholar
  15. 15.
    M. Hutley, Diffraction Gratings, Ac. Pr. (1982).Google Scholar

Copyright information

© Springer Science+Business Media New York 1997

Authors and Affiliations

  • Lucie Adam
    • 1
  • Eli Simova
    • 1
  • Mohsen Kavehrad
    • 1
  1. 1.Electrical Engineering DepartmentUniversity of OttawaOttawaCanada

Personalised recommendations