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150-Gb/s SEFDM IM/DD transmission using log-MAP Viterbi decoding for short reach optical links
Optics Express
|January 18, 2019
Summary
Spectral efficient frequency division multiplexing (SEFDM) boosts optical communication speeds. A new low-complexity log-MAP Viterbi decoding algorithm enables maximum likelihood detection, achieving 150-Gb/s in short-reach transmissions.
Area of Science:
- Optical Communications
- Signal Processing
Background:
- Next-generation communication systems require enhanced spectral efficiency.
- Optical intensity modulation and direct detection (IM/DD) are key for high-speed transmissions.
Purpose of the Study:
- To apply Spectral Efficient Frequency Division Multiplexing (SEFDM) in beyond 100-Gb/s optical IM/DD systems.
- To develop a low-complexity decoding algorithm for Maximum Likelihood (ML) detection.
Main Methods:
- Proposed a logarithmic-maximum-a-posteriori (log-MAP) Viterbi decoding algorithm.
- Evaluated detection likelihood using a posteriori probability, considering noise and inter-carrier interference.
- Employed Viterbi decoding to retain only surviving paths for ML detection.
Main Results:
- The log-MAP Viterbi decoding scheme achieved optimal performance and global ML detection.
- Demonstrated 150-Gb/s SEFDM transmission over 2-km standard single mode fiber using 28-GHz bandwidth and 16-QAM.
- Achieved a bandwidth compression factor of 0.8, outperforming 32-QAM OFDM at the same bandwidth and data rate.
Conclusions:
- The proposed log-MAP Viterbi decoding scheme enhances SEFDM performance in optical systems.
- SEFDM shows superiority for high-speed, short-reach optical communication applications.
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