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Real time low-complexity adaptive channel equalization for coherent optical transmission systems
Optics Express
|March 4, 2020
Summary
A new adaptive channel equalization (ACE) algorithm for digital coherent optical systems reduces computational complexity by 40%. This novel ACE method maintains performance while improving polarization tracking ability.
Area of Science:
- Optical communications
- Digital signal processing
Background:
- Digital coherent optical systems require advanced signal processing for reliable data transmission.
- Adaptive Channel Equalization (ACE) is crucial for mitigating channel impairments in these systems.
- Conventional ACE algorithms can be computationally intensive, limiting their efficiency.
Purpose of the Study:
- To propose and demonstrate a novel low-complexity adaptive channel equalization (ACE) algorithm.
- To reduce the computational complexity of ACE in digital coherent optical systems.
- To evaluate the performance and polarization tracking capabilities of the proposed ACE algorithm.
Main Methods:
- The proposed ACE algorithm decomposes the conventional N-tap butterfly ACE into two N-tap polarization-independent filters and a 1-tap butterfly adaptive equalization filter.
- The algorithm was implemented and evaluated on a 10-Gb/s real-time coherent transmission platform.
- Computational complexity reduction was analyzed, focusing on multiplier operations in digital signal processing (DSP).
Main Results:
- The proposed ACE algorithm achieved approximately 40% reduction in multiplier operations compared to conventional methods.
- Experimental results demonstrated comparable performance to the conventional ACE algorithm in a 10-Gb/s system.
- The novel ACE algorithm exhibited superior polarization tracking ability.
Conclusions:
- The proposed low-complexity ACE algorithm offers significant computational advantages for digital coherent optical systems.
- The algorithm effectively balances performance and complexity, making it suitable for real-time applications.
- Enhanced polarization tracking ability is a key benefit of this novel equalization approach.
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