Optimisation of the chirp performance of electroabsorption modulators using a numerical system model

A model to simulate an electroabsorption modulator in a dispersive communications system is described and confirmed experimentally for a 5Gbit/s 100km system. Optimisation of the device shows that transmission of 10Gbit/s over 100km is possible.

Effects of pedestal suppression on gain-switched laser sources for 40 Gbit/s OTDM transmission

The performance of 40 Gbit/s optical time-division multiplexed (OTDM) communication systems can be severely limited when the extinction ratio of the optical pulses is low. This is a consequence of the coherent interference noise between individual OTDM channels. When taken alone, the multiple quantum well-distributed feedback laser+dispersion compensating fiber source exhibits a relatively poor extinction ratio which impairs its potential for use in a 40 Gbit/s OTDM system. However, with the addition of an electroabsorption modulator to suppress the pulse pedestals to better than 30 dB extinction, coherent interference noise is reduced, the bit-error-rate performance is greatly improved, and the source shows good potential for 40 Gbit/s OTDM communication.

Optical communication system performance using fibre Bragg grating dispersion compensators

Operating limits of a chirped fibre grating dispersion compensator are determined using a complete optical system model. A 10cm compensator extends the transmission range of an optimised 10Gbit/s MQW electroabsorption modulator from 80km to 425km.