Higher order dispersion equaliser of dispersionshifted fibreusing a lattice-form programmable optical filter

Abstract
The higher order (third order) dispersion of dispersion shifted fibre has been successfully compensated by using a lattice-form programmable filter fabricated on a planar lightwave circuit. The equaliser offers a dispersion slope of –15.8 ps/nm2 over 170 GHz in the 1.55 µm region. The effectiveness of the equaliser has been confirmed by the pulse transmission experiment in which the trailing ripples of pulses caused by the higher order dispersion of 300 km dispersion shifted fibre have been eliminated.