The Journal of Korean Institute of Communications and Information Sciences (한국통신학회논문지)

The Korean Institute of Commucations and Information Sciences (한국통신학회)
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On the Application and Optimization of M-ary Transmission Techniques to Optical CDMA LANs

Optical CDMA 근거리망을 위한 M-진 전송기술에 대한 연구

  • Published : 2004.08.01
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Abstract

Most research efforts on the OCDMA technology assume single-bit-per-symbol transmission techniques such as on-off keying. However, achieving high spectral efficiency with such transmission techniques is likely to be a challenging task due to the "unipolar" nature of optical signals. In this paper, an M-ary transmission technique using more than two equally-weighted codes is proposed for OCDMA local area networks, and ie BER performance and spectral efficiency are analyzed. Poison frame arrival and randomly generated codes are assumed for the BER analysis, and the probability of incorrect symbol detection is analytically derived. From the approximation, it is found that there exists an optimal code weight that minimizes the BER, and its physical interpretation is drawn in an intuitive and simple statement. Under the assumption of this optimized code weight and sufficiently large code dimension, it is also shown that the spectral efficiency of OCDMA networks can be significantly improved by increasing the number (M) of symbols used. Since the cost of OCDMA transceivers is expected to increase with the code dimension, we finally provide a guideline to determine the optimal number of symbols for a given code dimension and traffic load.

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References

  1. IEEE Network v.3 Emerging optical code-division multiple access communication systems J. A. Salehi
  2. IEEE Network v.14 Lighting the Local Area: Optical Code-Division Multiple Access and Quality of Service Provisioning A. Stok;E. H. Sargent
  3. Optics & Photonics News v.14 no.4 Optical CDMA J. Shah https://doi.org/10.1364/OPN.14.4.000042
  4. IEEE Journal on Selected Areas in Communications v.16 no.7 Code Division Multiplexing Lightwave Networks Based upon Optical Code Conversion K. Kitayama https://doi.org/10.1109/49.725198
  5. IEE Electronics Letters v.30 no.17 Wavelength hopping/time spreading code division multiple access systems L. Tancevski;I. Andonovic https://doi.org/10.1049/el:19940942
  6. Journal of Lightwave Technology v.16 no.4 Design of a New Family of Two Dimensional Codes for Fiber-Optic CDMA Networks E. S. Shivaleela;K. N. Kumar;A. Selvarajan https://doi.org/10.1109/50.664055
  7. IEEE Transactions on Communications v.37 no.8 Code Division Multiple-Access Techniques in Optical Fiber Networks-Part Ⅱ: Systems Performance Analysis J. A. Salehi;C. A. Brackett https://doi.org/10.1109/26.31182
  8. IEEE Communications Letters v.5 no.4 Optical CDMA Using 2-D Codes:The Optimal Single-User Detector T.-W. F. Chang;E. H. Sargent https://doi.org/10.1109/4234.917103
  9. Lecture Notes in Computer Science v.2402 Optimal Code Weight Selection for 2-D Optical CDMA Systems T. Kim;W. Sung;J. Choe https://doi.org/10.1007/3-540-45639-2_27
  10. IEEE GLOBECOM '96 v.3 M-ary FSK signalling for incoherent all-optical CDMA networks K. Iversen(et al.)
  11. Lecture Notes in Computer Science v.2402 A Comparative Study on the Performance of Detectors and Interference Models for OCDMA LANs Y. Yun;J. Choe;W. Sung https://doi.org/10.1007/3-540-45639-2_22
  12. IEE Electronic Letters v.30 no.1 Performance analysis of an optical correlator receiver for SIK DS-CDMA communication systems T. O'Farrel;S. Lochmann https://doi.org/10.1049/el:19940069
  13. An alternative expression of P[X>Y] for two independent Poisson random variables with different means J. Choe