All-optical M-ary ASK signal demultiplexer based on a photonic analog-to-digital conversion

An all-optical M-ary amplitude shift keying (ASK) signal demultiplexer is proposed and demonstrated. It allowed us to seamlessly demultiplex a high bit-rate optical M-ary ASK signal into on-off keying (OOK) signals without O/E conversion. It is composed of multilevel thresholding using self-frequency shift and OOK signal generation using optical interconnection. A level identification signal is provided as a result of multilevel thresholding and it is fed to an optical interconnection circuit which can generate corresponding OOK signals. We demonstrate the quadrature ASK signal demultiplexing at 100 Gsymbol/s and its error free operation at 10 Gb/s.