| dc.description.abstract | Optical Code Division Multiple Access (OCDMA) system is a perfect choice for
satisfying high communication demand because of the all-optical processing, simplified
network control, bandwidth efficiency and security of such system. One of the coding
schemes of OCDMA is the Spectral Amplitude Coding OCDMA (SAC-OCDMA). This study focused on the SAC-OCDMA system, which recently received increasing attention because of its robust performance, phase insensitivity and flexible bandwidth provisioning. This study aimed to analyze the performance of SAC-OCDMA system’s codes with cross-correlation, particularly Enhanced Double Weight (EDW) and Modified Double Weight (MDW) codes, by using direct detection technique, AND subtraction detection technique as well as modified-AND subtraction detection
technique. Theoretical and simulation analyses using Optisystem Version 7.0 software
were performed with reference to the parameters in the ITU-T G.652 standard. Analysis
results show that the use of an ideal detection technique is more efficient than using the
right type of code in reducing bit error rates (BERs) as well as eliminating multiple
access interference (MAI) and phase induced intensity noise (PIIN). At 100 users, the
BERs of the MDW code with the AND subtraction detection technique and modified-
AND subtraction detection technique are and , respectively.
Whereas, the BER of EDW and MDW codes that utilized the modified-AND subtraction
technique are and respectively. The performances of EDW and
MDW codes present different outcomes depending on the parameter analyzed. The
modified-AND subtraction detection technique shows better performance than AND
subtraction and direct detection techniques. The effectiveness of a SAC-OCDMA system
in long-distance transmission with only single Light Emitting Diode (LED) and one
optical amplifier was also verified. In long-distance transmission, the modified-AND
subtraction detection technique exhibits a better performance than the AND subtraction
detection technique. For the same quality of service at a BER of , the
modified-AND subtraction detection technique allows 46.98% and 24.21% longer
transmission distance than the AND subtraction detection technique with MDW code
and EDW code, respectively. Hence, the ideal type of detection should be the focus in
SAC-OCDMA systems to reduce BER, MAI and PIIN furthermore, optimize the system
greatly and effectively. | en_US |
