New Encoder/Decoder with Wavelength/Time 2-D Codes for Optical CDMA Network

광 부호 분할 다중접속 네트워크를 위한 파장/시간 2차원 코드의 새로운 부호기/복호기

  • 황유모 (명지대학교 통신공학과)
  • Published : 2009.05.01


We propose a new encoder/decoders based on an tune able wavelength converter(TWC) and an arrayed waveguide grating(AWG) router for large capacity optical CDMA networks. The proposed encoder/decoder treats codewords of wavelength/time 2-D code simultaneously using the dynamic code allocation property of the TWC and the cyclic property of the AWG router, and multiple subscribers can share the encoder/decoder in networks. Feasibility of the structure of the proposed encoder/decoder for dynamic code allocation is tested through simulations using two wavelength/time 2-D codes, which are the generalized multi-wavelength prime code(GMWPC) and the generalized multi-wavelength Reed-Solomon code(GMWRSC). Test results show that the proposed encoder/decoder can increase the channel efficiency not only by increasing the number of simultaneous users without any multiple-access interference but by using a relatively short length CDMA codes.


Optical CDMA networks;New encoder/decoder;Dynamic code allocation;Wavelength/time 2-D code;Arrayed waveguide grating(AWG) router


  1. S. W. Lee, and D. H. Green, 'Coding for coherent optical CDMA networks,' IEE Proceedings-Communications, Vol. 145, No.3, pp. 117-125, June 1998
  2. D. D. Sampson, and D. A. Jackson, 'Spread-spectrum optical fiber network based on pulsed coherent correlation,' Electronics Letters, Vol. 26, No. 19, pp. 1550-1552, 13th Sept. 1990
  3. X. Wang, K. T. Chan, Y. Liu, L. Zhang, and I. Bennion, 'Novel temporal/spectral coding technique based on fiber Bragg gratings for fiber optic CDMA application,' Optical Fiber Communication Conference 1999, OFC '99. Technical Digest, Vol. 2, pp. 341-343, Feb. 1999
  4. H. S. Jung, J. M. Park, W. S. Ko, S. Shin, and H. Hwang, 'Large capacity shared-type optical CDMA encoder/decoder,' The Conference Proceedings of ICEE 2004, Vol. 1, pp. 457-462, July, 2004
  5. G-C. Yang, and W. C. Kwong, 'Performance comparison of multi wavelength CDMA and WDMA +CDMA for fiber-optic networks,' IEEE Trans. on Communications, Vol. 45, No. 11, pp. 1426-1434, Nov. 1997
  6. S. Yegnanarayanan, A. S. Bhushan and B. Jalali, 'Fast wavelength hopping time-spreading encoding/decoding for optical CDMA,' IEEE Photonics Technology Letters, Vol. 12, No.5, pp. 573-575, May. 2000
  7. A. J. Mendez, R. M. Gagliardi, V. J. Hernandez, C. V. Bennett, and W. J. Lennon, 'Design and performance analysis of wavelength/time (W/T) matrix codes for optical CDMA,' Journal of Lightwave Technology, Vol. 21, No. 11, pp. 2524-2533, Nov. 2003
  8. J. A. Salehi, and C. A. Brackett, 'Code division multiple-access techniques in optical fiber networks-part II: Systems performance analysis,' IEEE Trans on Communications, Vol. 37, No.8, pp. 834-842, Aug. 1989
  9. L. Tancevski, and I. Andonovic, 'Wavelength hopping/time spreading code division multiple access systems,' Electronics Letters, Vol. 30, No. 17, pp. 1388-1390, 18th Aug. 1994
  10. W. De Zhong, and R. S. Tucker, 'Wavelength routing-based photonic packet buffers and their applications in photonic packet switching systems,' Journal of Lightwave Technology, Vol. 16, No. 10, pp. 1737-1745, Oct. 1998
  11. Kyoungsik Yu, Namkyoo Park, 'Design of new family of two-dimensional wavelength-time spreading codes for optical code division multiple access networks,' Electronics Letters, Vol. 35, No. 10, pp. 830-831, June 1999