Colorless coherent receiver using 3x3 coupler hybrids and single-ended detection

Area of Science:

• Optical Communications
• Coherent Receiver Technology
• Photonic Integrated Circuits

Background:

• Traditional coherent receivers face challenges with wavelength tuning and complexity.
• Colorless optical receivers are crucial for flexible and scalable wavelength-division multiplexing (WDM) networks.
• Polarization-division-multiplexing quadrature-phase-shift-keyed (PDM-QPSK) modulation offers high spectral efficiency.

Purpose of the Study:

• To demonstrate a single-ended colorless coherent receiver architecture.
• To evaluate the performance of the receiver for high-speed data transmission.
• To assess the receiver's applicability in long-haul WDM systems.

Main Methods:

• Utilized symmetric 3x3 couplers for optical hybrid implementation.
• Employed a single-ended receiver design to reduce complexity.
• Tested the receiver with fifty-five 112-Gb/s PDM-QPSK channels.
• Evaluated performance in back-to-back and 2560-km fiber transmission scenarios.

Main Results:

• Achieved colorless reception of fifty-five 112-Gb/s PDM-QPSK channels.
• Demonstrated a penalty of less than 1 dB in back-to-back operation.
• Confirmed robust performance in a 2560-km wavelength-division multiplexing (WDM) transmission system.

Conclusions:

• The developed single-ended colorless coherent receiver offers a promising solution for future optical networks.
• The use of symmetric 3x3 couplers simplifies receiver design while maintaining high performance.
• The receiver's capability for colorless reception is validated for both short-reach and long-haul applications.