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DFT-Spread Spectrally Overlapped Hybrid OFDM-Digital Filter Multiple Access IMDD PONs
Abdulai Sankoh1, Wei Jin1, Zhuqiang Zhong1
1School of Computer Science and Electronic Engineering, Bangor University, Bangor LL57 1UT, UK.
Sensors (Basel, Switzerland)
|September 10, 2021
Summary
A new digital filter multiple access (DFMA) PON technique improves upstream transmission performance by reducing peak-to-average power ratio (PAPR). This allows for lower converter resolution and increased data rates in optical networks.
Area of Science:
- Optical Communications
- Signal Processing
Background:
- Passive Optical Networks (PONs) are crucial for broadband access.
- Intensity Modulation/Direct Detection (IMDD) PONs face challenges in upstream transmission performance.
Purpose of the Study:
- To propose and evaluate a novel DFT-spread DFMA PON system.
- To optimize ONU transceiver parameters for enhanced upstream performance.
Main Methods:
- Employing Discrete Fourier Transform (DFT)-spread in ONUs and OLT.
- Conducting detailed numerical simulations for performance analysis.
Main Results:
- Achieved significant PAPR reduction (>2 dB) and CR reduction (1 dB).
- Demonstrated tolerance to reduced DAC/ADC resolution (6 bits at FEC limit).
- Improved upstream power budget (>1.4 dB) and increased aggregate upstream rate (up to 10%).
Conclusions:
- The DFT-spread DFMA PON effectively enhances upstream transmission performance.
- The proposed system maintains PON features while offering superior performance and efficiency.
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