Transmission Effects in Wavelength Division Multiplexed Chaotic Optical Communication Systems

In this study we present the influence imposed by the coexistence of wavelength division multiplexed (WDM) channels on a chaotic optical communication system tested in an installed network environment. Both conventional carriers that carry 10 Gb/s data sequences and chaotic carriers used for data-encrypted channel transmission have been considered in a dense WDM configuration. Inter-channel interference, channel polarization and cross-phase modulation are some dominant phenomena identified to affect the synchronization process of well-match chaotic optical oscillators. The efficiency of data recovery of the conventional and chaos encrypted channels is analyzed. 1.25 Gb/s data sequences, that are completely hidden propagate along the transmission link, are finally recovered by the authorized receiver-using forward error correction (FEC) methods-with bit error rates (BER) below 10^-12, for channel spacing of 0.8 nm and in parallel polarized adjacent channels. When orthogonal polarization states are employed the channel spacing can be further reduced to 0.65 nm without sacrificing in the recovery performance.