Broadband Transmission System Development and Security-I

Optical Code Division Multiple Access (OCDMA) can provide high−speed connections with bandwidth sharing and secure communications in next generation optical access networks. Spectral amplitude coding (SAC) in OCDMA systems has been exploited in the optical networking units of passive optical networks (PONs). However, in the on−off keying, the codewords are uni−dimensional and require a longer code length to accommodate more simultaneous users in PONs. In addition, the performance of OCDMA systems is limited by the multi−user interference (MUI). To address this issue, codes with two−code keying (TCK) are proposed to remove MUI. In this project, we propose a new code family, called extended perfect difference codes (EPD codes), and the corresponding encoding/decoding architecture for spectral amplitude coding (SAC) optical code division multiple access (OCDMA) systems using a two-code keying scheme (TCK). The proposed system can eliminate multi-user interference (MUI) and suppress phase-induced intensity noise (PIIN). We propose extended perfect difference codes (EPD codes) with TCK to further reduce the phase−induced intensity noise (PIIN), in order to support more simultaneous users. By employing the proposed EPD codes, the variance of PIIN current is effectively reduced. We also propose a novel array waveguide grating (AWG) architecture to decrease the power loss and complexity of the optical line terminal (OLT). In addition, with EPD codes, we design an encoding/decoding architecture based on the array waveguide grating (AWG) architecture, to reduce the power loss and the complexity of the optical line terminal (OLT).

Project ID:PB10009-0198
External Project ID:NSC100-2218-E182-005