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One dimensional encoding in optical communications has limitations in terms of the number of supported users and large bandwidth consumption. This study presents a new algorithm to generate two-dimensional (2D) encoding utilizing permutation vectors (PV) theory for incoherent multiple access network to suppress multiple access interference (MAI) and system complexity. The proposed code design approach is based on spectral/spatial techniques for code generation. All possible combinations of PV code-sets are obtained by utilizing all permutations of the vectors with the repetition of each vector weight (W) times. Furthermore, the 2D-PV code-set is constructed by combining two code sequences of the 1D-PV code. Furthermore, the transmitter–receiver architecture of the 2D-PV spectral/spatial (S/S) code based OCDMA system is presented. The Gaussian approximation is used to analyze the performance of the proposed OCDMA system with 2D- PV code by considering various noise sources (shot, thermal, and PIIN). Results indicate that the 2D-PV code provides increased cardinality by eliminating phase induced intensity noise (PIIN) effects with a minimum likelihood of interference between multiple user data. Simulation implementations validate the proposed system performance for an agreeable bit error rate (BER) of 10–9 [ABSTRACT FROM AUTHOR]

We present a comparative analysis of performance characteristics of the optical code-division multiple-access systems, which are based on spectralamplitude coding (SAC) and are implemented using eight different one-dimensional optical codes and a multi-array laser. We try to find the best code for the SAC systems by taking into consideration such parameters as system requirements for the number of users, the data rate and the type of network suitable for a particular code. Our simulations reveal that the capacity of the SAC systems can be improved when those systems are implemented with a laser rather than incoherent light source. Moreover, we demonstrate that the laser-based SAC system performs well in terms of high data rates, which is followed by improved bit error rates occurring with increasing number of users. As a trade-off among different performance characteristics, different optical codes under analysis can be applied for different specific communication systems. The suggested codes support the maximal data rates up to 12 Gbps for approximately 50 users. The maximal fibre length that supports error-free transmission is equal to 70 km. [ABSTRACT FROM AUTHOR]