A new family of 2D wavelength/time codes with large cardinality for incoherent spectral amplitude coding OCDMA networks and analysis of its performance

A new family of two-dimensional wavelength/time codes (2D-W/T-MQC/MQCs) and its system structure of encoder/decoder are proposed, which is based on tunable optical fiber delay lines (TOFDLs) and fiber Bragg gratings (FBGs). Multiple-access interference (MAI) can fully be eliminated by using a wavelength/time balanced detector structure at the receivers. Furthermore, the performance of the system is also analyzed by taking into account the phase-induced intensity noise (PIIN), shot noise, and thermal noise. The simulation results reveal that the new code family possesses higher signal-to-noise ratio (SNR) and lower bit-error rate (BER) than the family of one-dimensional spectral amplitude coding modified quadratic congruence codes (1D-SAC-MQCs) and that of the two-dimensional wavelength/spatial M-matrices codes (2D-W/S-M-Matrices) so that a larger number of subscribers can be supported simultaneously. Additionally, the 2D-W/T-MQC/MQC system requires less signal power for each light source under the same error-free condition. As a result, the network based on the new code family will support more active users and utilize the frequency bandwidth more efficiently.

[1]  Anshi Xu,et al.  A new family of 2-D optical orthogonal codes and analysis of its performance in optical CDMA access networks , 2006, Journal of Lightwave Technology.

[2]  Hossam M. H. Shalaby,et al.  Modified quadratic congruence codes for fiber Bragg-grating-based spectral-amplitude-coding optical CDMA systems , 2001 .

[3]  Xiang Zhou,et al.  Code for spectral amplitude coding optical CDMA systems , 2000 .

[4]  Jen-Fa Huang,et al.  Two-dimensional M-matrices coding in spatial/frequency optical CDMA networks , 2003 .

[5]  B. Tell,et al.  Active optical NOR logic devices using surface-emitting lasers , 1992, IEEE Photonics Technology Letters.

[6]  Xu Wang,et al.  Analysis of beat noise in coherent and incoherent time-spreading OCDMA , 2004, Journal of Lightwave Technology.

[7]  Moshe Tur,et al.  Hybrid wavelength hopping/time spreading code division multiple access systems , 1996 .

[8]  Hongxi Yin,et al.  A new family of 2-D optical orthogonal codes and analysis of its performance in optical CDMA access networks , 2006 .

[9]  David J. Richardson,et al.  Optical Code Division Multiple Access Communication Networks: Theory and Applications , 2009 .

[10]  Guu-chang Yang,et al.  Multiple-wavelength optical orthogonal codes under prime-sequence permutations for optical CDMA , 2005, IEEE Transactions on Communications.

[11]  M. Kavehrad,et al.  An optical CDMA system based on spectral encoding of LED , 1993, IEEE Photonics Technology Letters.

[12]  Mohsen Kavehrad,et al.  Optical code-division-multiplexed systems based on spectral encoding of noncoherent sources , 1995 .