Rayleigh Scattering Robust Access Network by λ-Shifting through Extraction of Suppressed RZ Clock Harmonic (original) (raw)
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We investigate both theoretically and experimentally how the use of an all-optical decision element (ODE) in front of a conventional receiver improves, in return-to-zero (RZ) systems, the receiver performance when the signal bandwidth exceeds the bandwidth of the available optoelectronic components. A theoretical analysis of the ODE behavior shows the field of applicability of the investigated solution. The experimental evaluation of the performance improvement in an RZ system is realized using an ODE based on two cascaded nonlinear optical loop mirrors. Benefits in terms of bit error rate for different signal bandwidths and for a different received optical signal-to-noise ratio are presented. Substantial agreement of the experimental results with the theoretical analysis is obtained. The impact of the ODE in the presence of relevant thermal noise at the receiver is also considered. The ODE can extend the use of common band-limited receivers to wide-bandwidth signals and can be an alternative solution to the development of wideband receivers.
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All-Optical RZ-to-NRZ Conversion of Advanced Modulated Signals
IEEE Photonics Technology Letters, 2000
A generic scheme for return-to-zero (RZ) to nonreturn-to-zero (NRZ) format conversion of optical signals is analyzed. It relies on a simple delay interferometer with frequency periodicity twice as high as the input symbol rate and a subsequent optical band-pass filter. Simulation results at 40 Gbaud indicate the compatibility of the technique with a variety of advanced modulation formats. RZ-to-NRZ conversion of 40 Gb/s differential phase shift keying signals is experimentally demonstrated with 1.5 dB power penalty compared to the backto-back measurement.
IEEE Journal of Selected Topics in Quantum Electronics, 2000
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