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Updated: Mar 19, 2026
07:45
Quasi-light Storage for Optical Data Packets
Published on: February 6, 2014
11.4K
Low-complexity carrier synchronization for PS 64-QAM based on kernel RLS and zero-averaging blind phase search
Applied Optics
|March 17, 2026
Summary
This study introduces a novel two-stage carrier synchronization method for high-speed optical communication. The technique improves data transmission accuracy and extends reach, outperforming existing algorithms.
Area of Science:
- Optical Communications
- Digital Signal Processing
Background:
- Increasing demand for high-speed data transfer necessitates advanced signal processing.
- Probabilistic shaping requires modifications for error-free transmission.
Purpose of the Study:
- To propose a novel two-stage carrier synchronization method.
- To improve generalized mutual information (GMI) and nonlinear tolerance in optical systems.
Main Methods:
- Combining Kernel Recursive Least-Squares (KRLS) filter with zero-averaging Blind Phase Search (BPS).
- Jointly synchronizing phase and frequency, compensating for nonlinear phase noise.
Main Results:
- Significant GMI improvement for probabilistically shaped 64-QAM at 33.33 GBaud.
- Maintained accurate synchronization and high GMI where FFT-based methods fail.
- Achieved 4 dB OSNR gain and extended reach to 8000 km.
- Reduced computational load for real-time processing.
Conclusions:
- The proposed method enhances nonlinear tolerance and transmission reach.
- It offers a computationally efficient solution for long-haul coherent systems.
- The method is well-suited for real-time digital signal processing applications.
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