Homodyne crosstalk tolerance enhancement by all-active MZI-SOA wavelength converters

In this paper, we experimentally investigate the use of an all-active MZI-SOA wavelength converter to alleviate the signal degradation due to the homodyne crosstalk. In this experiment, the homodyne crosstalk level was varied from -40 dB to -21 dB. The data signal and the simulated homodyne crosstalk were combined together and were then fed into an Alcatel 1901 ICM all-active MZI-SOA wavelength converter. The all-active MZI-SOA was tuned to be in out-of-phase mode for better 2R optical regeneration performance and co-propagation scheme was used for more efficient wavelength conversion. The transfer characteristics of the all-active MZI exhibited a sharp thresholding behavior such that the flat regions were used to clamp the amplitude fluctuation due to the homodyne crosstalk.