Total date rate of multi-wavelength 2R regenerators for time-interleaved RZ-OOK signals.

Multi-wavelength regeneration free of inter-channel crosstalk is desirable for wavelength division multiplexing (WDM) systems, especially from the cost-effectiveness point of view. This paper presents the design rules of time-interleaved multi-wavelength 2R regeneration systems based on data-pump four wave mixing (FWM) effect, and several key factors, such as FWM bandwidth, wavelength assignment, and duty cycle, are comprehensively taken into account. The total data rate of time-interleaved WDM regeneration systems along with polarization multiplexing or bidirectional transmission are discussed, which are mainly determined by temporal overlap, spectral broadening and FWM bandwidth. As two examples, an eight-wavelength unidirectional regenerator using polarization multiplexing is designed by optimizing the fiber birefringence, and a six-wavelength bidirectional regenerator is demonstrated by experiment. Each is expected to have a total data rate of about 200 Gb/s for the optical RZ-OOK signals, and the wavelength number is increased at the expense of spectral efficiency.