Demonstration of RF oscillator-free radio-over-fibre system by all-optically processing received wireless signal

Presented is an innovative full-duplex radio-over-fibre (RoF) transmission system with a simplified base and central station by reusing the received wireless signal. All-optical signal processing is introduced, based on a semiconductor optical amplifier at the central station that simultaneously all-optically removes the amplitude shift-keying (ASK) modulation of the upstream signal, allowing for reusing the microwave carrier, and acts as an optical intensity modulator, reusing the optical carrier to impose the downstream data information. By reusing the radio-frequency carrier, no local oscillator is required at the station sites, simplifying significantly the RoF system. Experimental results show error-free operation at 1.25Gbit/s ASK data information on a 15GHz microwave carrier.