5 Gbit/s optical phase diversity homodyne detection experiment

A 5 Gbit/s phase diversity homodyne detection experiment has been performed by using a high-speed 1.5 mu m distributed-feedback laser diode with frequency-shift-keying modulation, a 3*3 optical fibre coupler for a 120 degrees optical hybrid, three matched wideband receivers and wideband squaring circuits for signal demodulation.