Establishing a Spectral Optical CDMA System Involving the Use of Two Mutually Orthogonal States of Polarizations Using 1-D Two-Distinct Codes With Two-Code Keying

We propose 1-D Two-Distinct codes with two-code keying (TCK) using two mutually orthogonal states of polarization (SOP) in spectral components as a new code family for spectral amplitude coding (SAC) in optical code division multiple access (OCDMA) networks. Our proposed code structure operates the 1-D Two-Distinct codes with TCK using two mutually orthogonal SOP in spectral components to achieve a simple architecture. The modified cross-correlation within the 1-D Two-Distinct codes with TCK facilitates the transition from one code keying (OCK) to the generation of TCK. We design 1-D Two-Distinct codes with TCK to eliminate multiple user interference (MUI) caused by other simultaneous users through modified cross-correlation, thereby improving code operation. Although the recovered bits are affected by phase-induced intensity noise (PIIN), our proposed system can suppress PIIN. The numerical results show that our proposed system supports up to 45 simultaneous users and provides higher data transmission rates of 2.5 Gbps compared to other systems using 1-D SP codes with TCK, 1-D BIBD codes, and 1-D BDS codes with TCK.