We demonstrate the longest bidirectional and unrepeatered semiconductor optical amplifier (SOA)-based transmission of 16 differential phase-shift keying (DPSK), 100-GHz-spaced channels at 10 Gb/s over standard single-mode fiber. Key techniques are: the use of DPSK constant-envelope modulation format to prevent nonlinear distortions in the SOAs; a new type of wavelength-division-multiplexing-DSPK demodulator to strongly enhance the signal tolerance to chromatic dispersion. After 120-km transmission, 1.8- to 3-dB power penalty was found for the 16 channels.
- Optical communications
- Optical differential phase-shift keying (DPSK)
- Semiconductor optical amplifiers (SOAs)
- Wavelength-division-multiplexing (WDM) systems