Abstract—In this paper, we investigate the use of the modified-AND subtraction detection to assuage the intensity noise in spectral-amplitude coding optical code-division multiple-access (SAC-OCDMA) systems. This detection approach is based upon reducing the received power to the decoders by dividing the weight of the utilised code sequence. The proposed technique has the ability to suppress the influence of multiple-access interference (MAI), in addition to alleviate the intensity noise effect. We simulate the system performance of the proposed detection technique using OptiSystem software Version 9.0. The software considered the entire practical impacts in the system, such as nonlinear effect, dispersion, and attenuation in the fiber. The simulation results based on the modified quadratic congruence (MQC) code show that the modified-AND subtraction detection offer best bit-error rate (BER) performance compared to traditional AND subtraction detection.

Index Terms—Optical code-division multiple-access,spectral-amplitude coding (SAC), Modified-AND subtraction detection, multiple-access interference, intensity noise.

The authors are with the School of Computer and Communication Engineering, University Malaysia Perlis (UniMAP), Perlis, Malaysia;Corresponding author: Hamza M. R. Al-Khafaji (e-mail:eng.hamza.alkhafaji@gmail.com).

Cite: Hamza M. R. Al-Khafaji, S. A. Aljunid, and Hilal A. Fadhil, "Modified-AND Subtraction Detection Technique Based on Weight-Division for SAC-OCDMA Systems," International Journal of Computer and Electrical Engineering vol. 4, no. 6, pp. 861-863, 2012.