Analysis of bit rate dependence up to 80 Gbit/s of a simple wavelength converter based on XPM in a SOA and a shifted filtering

摘要

This paper provides the analysis of wavelength converted pulses obtained with a simple semiconductorudoptical amplifier (SOA)-based wavelength conversion scheme, which exploits cross phase modulationud(XPM) in an SOA in conjunction with shifted filtering. The analysis includes experimental measurementsudof the back-to-back system performances as well as frequency-resolved optical gating (FROG) characterisationsudof the wavelength converted pulses. These measurements are implemented at different bit ratesudup to 80 Gbit/s and for both red and blue-shifted filtering, particularly showing different patterning effectuddependencies of red and blue-shifting techniques. This analysis is developed by the addition of a numericaludstudy which corroborates the experimental results. A further understanding of the different performancesudof red and blue filtering techniques, presented in the literature, can thus be proposed. Theudplacement of the filter to undertake red-shifted filtering (RSF) allows us to achieve very short pulseudwidths but high bit rate operation is limited by pattern effects. The blue-shifted filtering (BSF) techniqueudshows optimum performance as regards to patterning effects even if the wavelength converted pulsesudcan be larger.