A technique for optical pulse regeneration and reshaping using feedforward current injection in a semiconductor optical amplifier is reported. By matching the shape and phase of the injected current and the incoming optical pulse, the optical amplifier gain is set to increase with the amplifier input optical signal level, resulting in an enhanced extinction ratio for the output pulse. It has been experimentally demonstrated that a proper forward gain control improves the output extinction ratio by more than 5 dB for a system where the optical amplifier gain dynamics limits the maximum pulse rate to 500 Mbits/s. (C) 1999 John Wiley & Sons, Inc.2113942