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Spectrally efficient localized carrier distribution scheme for multiple-user DFT-S OFDM RoF- PON wireless access
1Department of Communication Science and Engineering, and State Key Lab of ASIC & System, Fudan University, Shanghai 200433, China.
Optics Express
|February 8, 2013
Summary
This study introduces a novel multi-tone generation scheme for 60 GHz mm-wave communication, enhancing carrier efficiency by 33.3%. The developed multiple-user discrete Fourier transform spread optical orthogonal frequency-division multiplexing (DFT-S OFDM) Radio-over-fiber (RoF) system demonstrates feasibility for passive optical networks (PON).
Area of Science:
- Wireless Communication
- Optical Networking
- Signal Processing
Background:
- Existing wireless systems face challenges in efficient spectrum utilization for high-frequency millimeter-wave (mm-wave) bands.
- Radio-over-fiber (RoF) systems offer a promising solution for delivering high-speed wireless services over optical networks.
- Passive Optical Networks (PONs) are crucial for scalable and cost-effective fiber optic infrastructure.
Purpose of the Study:
- To propose and validate a modified localized carrier distribution scheme for generating 60 GHz mm-wave signals.
- To present a multiple-user discrete Fourier transform spread optical orthogonal frequency-division multiplexing (DFT-S OFDM) RoF system applicable to PONs.
- To demonstrate the spectral efficiency and performance of the proposed system for multiple wireless users.
Main Methods:
- Development of a multi-tone generation technique for localized carrier distribution.
- Implementation of a multiple-user DFT-S OFDM Radio-over-fiber Passive Optical Network (RoF-PON) architecture.
- Experimental demonstration of an 8 x 4.65 Gb/s system over 40 km fiber and 60 GHz wireless links.
Main Results:
- Achieved a 33.3% improvement in carrier utilization efficiency using the modified localized carrier distribution scheme.
- Demonstrated a 2.3 dB reduction in receiver power compared to conventional OFDM.
- Validated the feasibility of the spectrally efficient multiple-user RoF-PON scheme through Bit Error Rate (BER) performance analysis for 8 users.
Conclusions:
- The proposed modified localized carrier distribution scheme effectively generates 60 GHz mm-wave signals with enhanced carrier efficiency.
- The multiple-user DFT-S OFDM RoF-PON system is a viable and spectrally efficient solution for future wireless access networks.
- The system's performance confirms its suitability for high-capacity, multi-user wireless communication over optical infrastructure.
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