Self-homodyne detection in optical coherent transmission using extracted carrier as the local oscillator by saturated SOA

We proposed a self-homodyne coherent detection technique in coherent optical transmission using extracted carrier from the received optical signal by saturated semiconductor optical amplifier (SOA) as LO. Saturated SOA has data erasing characteristic, so LO light can be extracted from the received optical signal by erasing modulated data of the optical signal. In the proposed scheme, there is no CFO because LO light originating from the received signal has a totally same wavelength with the signal. Thus, expensive OFLL or complex CFO compensate algorithm can be avoided; also, colorless operation is possible, and there is no additional requirement of optical fiber for LO light transmission, so it is cost efficient. The test bed has been set up, and the feasibility was experimentally demonstrated.