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Fine-grained spectral-efficient adaptive DMIM-OFDM for VLC via non-power-of-two constellation design
Optics Letters
|July 31, 2026
Summary
This study introduces a fine-grained spectral efficiency (SE) adaptive scheme for visible light communication (VLC) systems. The new method enhances data transmission rates by reducing adaptation granularity, minimizing channel resource wastage.
Area of Science:
- Optical Communications
- Signal Processing
- Information Theory
Background:
- Visible light communication (VLC) systems face channel resource wastage due to coarse spectral efficiency (SE) granularity.
- Adaptive modulation schemes are crucial for optimizing VLC performance.
Purpose of the Study:
- To propose a fine-grained SE adaptive scheme for VLC systems.
- To reduce channel resource wastage and improve transmission rates.
Main Methods:
- Design of a concentric-circle-based non-power-of-two dual-mode constellation.
- Implementation of a fine-grained SE adaptive discrete multi-tone modulation orthogonal frequency-division multiplexing (DMIM-OFDM) scheme.
- Reduction of SE adaptation granularity from 1 bit/s/Hz to 0.5 bit/s/Hz.
Main Results:
- Achieved integer SEs using the novel constellation design.
- Enabled more precise signal-to-noise ratio (SNR) matching.
- Demonstrated a transmission rate gain of up to 7.45% compared to the 1 bit/s/Hz granularity scheme.
Conclusions:
- The proposed fine-grained SE adaptive DMIM-OFDM scheme effectively reduces channel resource wastage in VLC systems.
- The novel constellation design allows for finer SE adaptation, leading to significant transmission rate improvements.
- This approach offers a more efficient solution for adaptive VLC systems.
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