可见光通信（visible light communication，VLC）作为一种新兴的无线通信技术，是目前针对无线频谱资源紧张的有效解决方案之一。根据VLC接收机电域接收信噪比的频域包络不变特性，提出一种低复杂度的自适应正交频分复用链路设计方案，并进行实验验证。结果表明，与已有的自适应等比特传输方案相比，本设计方法更好地利用了无线光信道的带宽资源，传输速率和BER性能等指标有明显提升。
As an emerging wireless communication technology, visible light communication (VLC) is one of the effective solutions for the shortage of wireless spectrum resource. In this work, a low-complexity design scheme of orthogonal frequency division multiplexing (OFDM) system is proposed based on the mask invariable characteristics of the received signal-to-noise rate of VLC in the electrical domain. The scheme is verified by the experiments. The experimental results show that, compared with the adaptive equal bits transmission scheme, the proposed adaptive OFDM system makes full use of the bandwidth resources of wireless optical channel, and it shows improvements in transmission rate and BER performance.
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