We numerically demonstrate 160 Gb/s densely dispersion-managed soliton tran
smission in a single channel over 2000 km in the dispersion-flattened fiber
s in the presence of polarization mode dispersion and of targe variation in
group-velocity dispersion. The best performance is achieved by a proper de
sign of the dispersion profile with possible minimum average dispersion, so
that the soliton interactions are minimized.