Abstract

Hybrid Subcarrier Multiplexing (SCM) incorporating spectral amplitude coding optical code division multiple access (SAC-OCDMA) technology was investigated both mathematically and by simulation. The hybrid SCM/SAC-OCDMA system combined two schemes in such as a way that the resulting hybrid system is robust against the Multi- Access Interference (MAI) and much enhanced the channel data rate. In this paper, we describe the improved performance of the hybrid SCM/SAC-OCDMA system based on the use of spectral amplitude coding to suppress  impairments and to improve the overall system improve the overall sensitivity of system performance at a BER of 10^-9. As a result, the proposed system based on Multi-Diagonal (MD) code shows better performance in comparison to the conventional code that employs the SAC-OCDMA system. We also evaluate the different design parameters under the maximum number of subcarriers (18 subcarriers in each optical channel) multiplexed for integrating OCDMA technology onto the existing fiber-wireless infrastructure at 155 M bit/s data rate for different fiber lengths. Further, a BER of 4.4 × 10^-10 was achieved based on the proposed system for 45 km at 1.21 GHz.

Key words: Subcarrier multiplexing (SCM), spectral amplitude coding optical code division multiple access (SAC-OCDMA), multi diagonal (MD) code.