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Faster-than-Nyquist and beyond: how to improve spectral efficiency by accepting interference
Giulio Colavolpe1, Tommaso Foggi, Andrea Modenini
1University of Parma, Dipartimento di Ingegneria dell’Informazione, and CNIT Research Unit, Parma, Italy. giulio@unipr.it
Optics Express
|January 26, 2012
Summary
We demonstrate faster-than-Nyquist signaling techniques for optical communications. These methods boost spectral efficiency, enabling 1 Tbps transmission over 200 GHz in long-haul links.
Area of Science:
- Optical Communications
- Signal Processing
Background:
- High-order modulation formats face theoretical and technological challenges in long-haul optical links.
- Spectral efficiency is crucial for increasing data rates in optical networks.
Purpose of the Study:
- To investigate time and frequency packing techniques for long-haul optical links.
- To assess the potential of these techniques in enhancing spectral efficiency.
Main Methods:
- Simulations of a realistic nonlinear long-haul optical link.
- Application of time and frequency packing, an extension of faster-than-Nyquist signaling.
Main Results:
- Achieved a spectral efficiency increase.
- Successfully demonstrated 1 Tbps data transmission.
- Transmission occurred over a 200 GHz bandwidth.
Conclusions:
- Time and frequency packing techniques offer a viable solution for overcoming limitations of high-order modulation.
- These techniques significantly enhance spectral efficiency in long-haul optical links.
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