Preconversion phase modulation of input differential phase-shift-keying signals for wavelength conversion and...

Area of Science:

• Optical communications
• Photonics
• Signal processing

Background:

• Multicasting is crucial for efficient data distribution in optical networks.
• Return-to-zero differential phase-shift keying (RZ-DPSK) offers high spectral efficiency and noise immunity.
• Wavelength conversion via four-wave mixing is a key technique for signal manipulation.

Purpose of the Study:

• To demonstrate a novel method for multicasting RZ-DPSK signals.
• To investigate the use of phase-modulated pumps for enhanced signal replication.
• To analyze the performance and efficiency of the proposed multicasting technique.

Main Methods:

• Utilizing phase modulation of both the input signal and co-pump lasers.
• Employing four-wave mixing for generating multiple signal copies.
• Characterizing conversion efficiency and receiver sensitivity penalty at a bit-error rate of 10⁻⁹.

Main Results:

• Successfully generated nine copies of a 50 Gbit/s RZ-DPSK data signal.
• Achieved an average conversion efficiency of approximately 0 dB.
• Observed an average receiver sensitivity penalty of 1.9 dB, with a worst-case of 2.3 dB.

Conclusions:

• The proposed method effectively enables multicasting of RZ-DPSK signals.
• Phase-modulated pumps offer a viable approach for efficient signal replication.
• The technique shows promise for future high-capacity optical communication systems.