Simulation analysis of wavelength-time (2-D) modified double weight code for optical CDMA system

Abstract

The explosive growth of bandwidth demand, together with advance in latest communication services and emerging applications has inspired huge interest in application of code division multiple access (CDMA) technique in optical network. The major interference factor in optical CDMA (OCDMA) is to overcome the multiple access interference (MAI) noise which induces the occurrence of bit error rate. Ideal code property with minimum cross-correlation will mitigate MAI, reduce phase induced intensity noise (PIIN) and expand code scalability. Part of the work devotes to analyzing how OCDMA can suit into the future generation of optical network. In this report the new incoherent two-dimensional (2-D) modified double weight (MDW) OCDMA wavelength-time is projected and demonstrated. The code is simulated for high performance. The good property of cross-correlation results in optimum PIIN suppression in comparison to 1-D MDW OCDMA code .This is reflected through high SNR value or low bit error rate (BER) as the cardinality increases. The comparison outcome of 2-D MDW code with 1-D MDW code indicates substantial performance improvements in cardinality, BER, bit rate and distance. Based on the simulation results the 2-D MDW OCDMA achieves high scalability; below 10-9 BER error floor. The combination of wavelength and time-chip can be further enhanced the overall system performance. The 2-D MDW OCDMA code has successfully mitigating MAI by the balance detection technique. The 2-D MDW OCDMA simulation model is developed to validate the realization of the code for BER, bit rate and distance performance. In short the 2-D MDW OCDMA code successfully suppresses PIIN and mitigating MAI which result in high cardinality, reduce Psr, high bit rate and distance.