A single sideband signal (504) is generated from an input optical signal (502). An optical phase modulator performs optical phase modulation on the input optical signal (502) in accordance with a control signal (520) to produce the single sideband signal (504). A converter (512) converts the input optical signal (502) into a corresponding electrical signal. A control signal generator (514, 516) generates the control signal (520) in response to an optical signal pulse shape of the input optical signal (502).