Overcoming fibre chromatic dispersion in high bit rate transmission

We have demonstrated that mid-span spectral inversion by four-wave mixing in a semiconductor optical amplifier can be used to effectively eliminate dispersion in high bit rate transmission. The technique has been used to achieve transmission of 1OGb/s signals from a directly modulated DFB over 200km dispersive fibre, and of 25ps gain-switched pulses over 100km dispersive fibre. The results show a complete elimination of degradation resulting from fibre chromatic dispersion. The former result represents more than a 40-fold increase in the bit rate distance product for the directly modulated signals by means of MSSI.