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Large-coverage underwater visible light communication system based on blue LED employing equal gain combining with
Applied Optics
|January 16, 2019
Summary
This study introduces a high-speed underwater visible light communication (VLC) system using advanced modulation and an integrated receiver array. It achieves over 1 Gbit/s, demonstrating a new benchmark for underwater data transmission.
Area of Science:
- Optoelectronics
- Optical Communications
- Underwater Technology
Background:
- Underwater visible light communication (VLC) systems face challenges in achieving high data rates over large coverage areas.
- Existing systems often struggle with alignment tolerances and signal degradation in aquatic environments.
Purpose of the Study:
- To develop and demonstrate a large-coverage underwater VLC system capable of high-speed data transmission.
- To evaluate the performance of quadrature amplitude modulation-discrete multitone (QAM-DMT) with an integrated positive-intrinsic-negative (PIN) array receiver for equal-gain combining (EGC).
Main Methods:
- Utilized a transmitter with a lens group and a blue-emitting silicon substrate light-emitting diode (458 nm).
- Employed an integrated 2x2 PIN array receiver for equal-gain combining (EGC).
- Implemented quadrature amplitude modulation-discrete multitone (QAM-DMT) for data transmission.
Main Results:
- Achieved a data rate exceeding 1 Gbit/s over 1.2 m underwater transmission with a 25 cm spot diameter and 11 cm alignment tolerances.
- Reached a data rate of 1.8 Gbit/s using parallel light reception.
- Demonstrated the highest data rates to date for large-coverage underwater VLC systems.
Conclusions:
- The integrated PIN array with QAM-DMT modulation and EGC is beneficial and feasible for high-speed underwater VLC.
- This technology shows significant potential for enhancing underwater communication capabilities.
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