Performance comparison of different receiver configurations in an all-optical chaotic transmission system

Abstract

A detailed investigation of the decoding properties of different receiver configurations in an all-optical chaotic transmission system is presented for two data-encoding techniques and for various dispersion compensation maps. A semiconductor laser subjected to optical feedback generates the chaotic carrier while data is encoded either by Chaotic Modulation (CM) or Chaotic Shift Keying (CSK) methods. The complete transmission module consists of various dispersion management maps, in-line amplifiers and Gaussian optical filters. The receiver, employing a high facet reflectivity laser, is either forming a closed-loop configuration operating at the non-amplification regime or a strongly injected open-loop one. For the latter configuration the possibility of utilizing an anti-reflection (AR) coated laser is also investigated. System's performance is numerically tested by calculating the Q-factor of the eye diagram of the 1 Gb/s received data. The influence of the optical power launched into fibre or the transmission distance to the quality of the decoded message has been investigated. The closed-loop scheme had better performance relative to the open-loop, while CSK method and maps utilizing Dispersion Shifted Fibres are superior to CM and that employing Dispersion Compensating Fibres respectively. When an AR-coated laser is used in the open-loop receiver setup, improved decoding performance occurs.