Adaptive intensity transformation-based phase retrieval with high accuracy and fast convergence

Area of Science:

• Optical communications
• Signal processing
• Photonics

Background:

• Phase-retrieval (PR) receivers reconstruct signals from intensity measurements without optical carriers.
• Current PR methods face challenges in calculation complexity and accuracy for high-speed applications.

Purpose of the Study:

• To develop a novel PR receiver with enhanced speed and accuracy for photonic interconnections.
• To overcome limitations of existing PR techniques in high-speed optical systems.

Main Methods:

• Proposed and demonstrated a PR receiver utilizing adaptive intensity transformation.
• Numerically reconstructed 56 GBaud Quadrature Phase Shift Keying (QPSK) signals after 80 km standard single-mode fiber transmission.

Main Results:

• Achieved fast convergence with only 50 iterations, significantly reducing computational complexity.
• Demonstrated high accuracy in reconstructing complex-valued signals.
• Reduced required optical signal-to-noise ratio by 1.95 dB (20% soft-decision FEC) and 1.89 dB (7% hard-decision FEC) compared to prior methods.

Conclusions:

• The adaptive intensity transformation PR receiver offers a viable solution for high-speed photonic interconnections.
• This advancement enables more efficient and robust optical signal reconstruction.
• The proposed method significantly lowers the optical signal-to-noise ratio requirements for reliable data transmission.