3 Gb/s Broadband Spectral Amplitude Coding - Optical Code Division Multiple Access (SAC-OCDMA) Based on Multi Diagonal and Walsh Hadamard Codes

摘要

The importune need of the subscribers to the vast speed of the download in the internet, motivate the researchers to discover new technologies such as Spectral Amplitude Coding-Optical Code Division Access (SAC-OPDMA) system. SAC-OCDMA is widely used in asynchronous network. This research is dedicated on the investigation of 3Gb/s broadband SAC-OCDMA for fifteen users based on Multi Diagonal (MD) and Walsh Hadamard (WH) codes. Since these codes have many important advantages such as zero cross-correlation, so they support the system the ability of removing the Multiple Access Interference (MAI). For increasing the number of the users sharing the same bandwidth is affordable or possible without using method of amplification or dispersion compensation fiber. The system is designed and simulated using OptiSystm version 7 and OptiGrating version 4.2. The results demonstrate the carrying out of transmission distance of 50 km, where the users' information reach the destination at BER lower than the floor value 10~(-9) for SAC-OCDMA based on MD code. Moreover, the BER of SAC-OCDMA system decreases as the power of the transmitted power increases, where the minimum obtained BER for MD code is10~(-34), while it is10~(-10) for WH code.