Generation of a pseudorandom dark soliton data trainandits coherent detection by one-bit-shifting witha Mach-Zehnder interferometer

New schemes are described for the generation and detection of a dark soliton pseudorandom data train. The dark soliton data are generated by an AND gate and T-flip-flop circuits. The dark soliton is detected by using a one-bit-shifting technique with a Mach-Zehnder interferometer, which converts the dark soliton signal into a non-return-to-zero (NRZ) signal.