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Performance analyses of polarization demultiplexing based on constant-modulus algorithm in digital coherent optical
1Department of Electrical Engineering and Information Systems, The University of Tokyo, 7-3-1 Hongo, Tokyo 113-8656, Japan. kikuchi@ginjo.t.u-tokyo.ac.jp
Optics Express
|June 7, 2011
Summary
Digital coherent optical receivers can demultiplex polarization using the constant-modulus algorithm (CMA). This study explains CMA physics for polarization demultiplexing, simulates performance limits, and demonstrates performance improvement methods.
Area of Science:
- Optical Communications
- Digital Signal Processing
Background:
- Digital coherent optical receivers enable advanced signal processing.
- Polarization demultiplexing is crucial for maximizing data capacity in optical systems.
- The constant-modulus algorithm (CMA) is a key technique for adaptive equalization.
Purpose of the Study:
- To elucidate the underlying physics of CMA for polarization demultiplexing.
- To analyze the performance limitations of CMA-based polarization demultiplexing.
- To demonstrate a method for enhancing the performance of CMA-based polarization demultiplexing.
Main Methods:
- Digital domain polarization demultiplexing using a 2x2 matrix.
- Application and analysis of the constant-modulus algorithm (CMA).
- Performance evaluation through computer simulations.
Main Results:
- Detailed explanation of CMA's mechanism in polarization demultiplexing.
- Identification of performance limitations in CMA-based systems.
- Successful demonstration of a performance improvement technique.
Conclusions:
- CMA is a viable digital signal processing technique for polarization demultiplexing.
- Understanding performance limits is essential for practical implementation.
- Methods exist to enhance the effectiveness of CMA in optical receivers.
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