Coding and Detection Techniques Used in SAC-OCDMA System: A Detailed Review

Optical communication has become need of the day being capable of offering high bandwidth and data processing at high speed to meet the requirement of seamless communications. In order to ensure security of data and bandwidth efficiency, coding techniques are mandatory. This paper presents detailed review of the technological developments in the field of Optical Code Division Multiple Access (OCDMA) specifically focusing on one of its implementation i.e. Spectral Amplitude Coded OCDMA (SAC-OCDMA) system. SAC-OCDMA has an inherent advantage in form of complete elimination of the Multiple Access Interference (MAI) that is why it has drawn the attention of researchers. Here various possible coding schemes, which can be implemented like Double Weight (DW), Modified DW (MDH), Enhanced DW (EDW), Multi Diagonal (MD) and Walsh Hadamard (WH) codes along with various detection techniques such as Complementary Subtraction Detection (CSD), Single Photodiode Detection (SPD), Direct Detection (DD), AND detection and modified-AND detection. The latest work on this topic has been thoroughly reviewed and will motivate, to peruse research in the field to develop new and modified technique, in order to improve the parameters such as bit rate, SNR, higher data rate etc.