A single channel, time-division-multiplexed 320Gbit/s data signal at 1.55 mu m has been successfully transmitted over a 120km long dispersion-managed fibre using 400fs optical pulses. The second and third-order dispersions in the transmission fibre were fully compensated for with a combination of 1.3 mu m singlemode fibre and dispersion slope compensation fibre. A walk-off free nonlinear optical loop mirror and a 1.53 mu m control pulse with a 1.1ps duration were used to demultiplex the signal to 100Gbit/s.