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Digital pilot aided carrier frequency offset estimation for coherent optical transmission systems.
Optics Express
|September 26, 2015
Summary
A novel digital pilot aids carrier frequency offset estimation in optical systems. This method offers wide range, high accuracy, and tolerance to dispersion, improving optical transmission performance.
Area of Science:
- Optical communications
- Digital signal processing
Background:
- Coherent optical transmission systems require accurate carrier frequency offset estimation (FOE).
- Conventional methods often involve pilot tone insertion, which can be complex or inefficient.
Purpose of the Study:
- To introduce a new digital pilot aided method for carrier frequency offset estimation.
- To demonstrate the advantages of this digital pilot approach over traditional schemes.
Main Methods:
- A digital pilot is generated and used as an indicator for FOE.
- Carrier frequency offset is determined by locating the digital pilot within the optical spectrum.
Main Results:
- The proposed method achieves wide-range FOE.
- High accuracy in estimation is demonstrated.
- The method is independent of modulation formats and does not require modulation removal.
- It exhibits high tolerance to residual chromatic dispersion (CD) and polarization mode dispersion (PMD).
Conclusions:
- The digital pilot aided FOE method provides a robust and efficient solution for coherent optical systems.
- Its independence from modulation formats and tolerance to impairments make it highly versatile.
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