OCDMA Code Utilization Increase: Capacity and Spectral Efficiency Enrichment

A novel spreading code-set is proposed to increase the optical CDMA networks capacity and spectral efficiency. The coding scheme is based on the prime code (PC) families, referred to as ´transposed modified prime codes (T-MPC)´. This code family doubles the cardinality of existing PC families. Since the time-shift is no longer a feature in T-MPC like in conventional modified prime codes (MPC), the code is not predictable and thus provides more physical layer security. The code structure is similar to MPC; therefore, its deployment in a system/network already running MPC will not require hardware revision. Due to the higher code utilization factor of this new code-set, greater number of users is accommodated under certain bit- error rate (BER) resulting in remarkable improvement in the network capacity and spectral efficiency (SE).