Fast frequency hopping codes applied to SAC optical CDMA network

• A new code family, fast frequency hopping code (FFH), was presented for applications in SAC optical CDMA network.
• A complete SAC optical CDMA system with moderate security was constructed.
• The numerical result shown that the SAC optical CDMA network using the proposed FFH code can provide favorable performance.

This study designed a fast frequency hopping (FFH) code family suitable for application in spectral-amplitude-coding (SAC) optical code-division multiple-access (CDMA) networks. The FFH code family can effectively suppress the effects of multiuser interference and had its origin in the frequency hopping code family. Additional codes were developed as secure codewords for enhancing the security of the network. In considering the system cost and flexibility, simple optical encoders/decoders using fiber Bragg gratings (FBGs) and a set of optical securers using two arrayed-waveguide grating (AWG) demultiplexers (DeMUXs) were also constructed. Based on a Gaussian approximation, expressions for evaluating the bit error rate (BER) and spectral efficiency (SE) of SAC optical CDMA networks are presented. The results indicated that the proposed SAC optical CDMA network exhibited favorable performance.