Performances of Spectral-Amplitude-Coding Optical CDMA systems

This paper presents the Spectral Amplitude Coding Optical Code Division Multiple Access (SAC-OCDMA) system using Super-imposed Fiber Bragg Grating (S-FBG) with balanced detection. We consider five unipolar families codes, namely the m-sequences, the perfect difference codes, the Balanced Incomplete Block Design (BIBD) codes, the Modified Quadratic Congruent (MQC) codes and the Modified Frequency Hopping (MFH) codes to encode/decode transmitted data. The system performances are evaluated by taken in consideration the effects of Multiple Access Interferences (MAI) and the noises at the receiver (thermal noise, dark noise, shot noise and beat noise). We evaluate the impact of codes, nature of optical source and bit rate on the BER of the SAC-OCDMA system. For perfect difference codes, simulations results are validated with measurements.