可见光通信（VLC）是一种新型无线光通信技术，它将照明和通信结合起来，因此具有极其广阔的应用前景，成为近年来研究的热点。目前VLC发展的主要瓶颈在于，LED有限的调制带宽限制了VLC系统的传输速率。为解决这一问题，可见光通信系统中使用了硬件预均衡电路，设计并使用了单双级联桥T幅度均衡器，结合自适应比特功率加载正交频分复用（OFDM）技术，有效地提高了可见光通信系统的调制带宽和传输速率。
Visible light communication (VLC) is an emerging wireless optical communication technology, which combines illumination and communication. So it has a broad application prospect that makes it a research hotspot in recent years. The main challenge of VLC's development is the limited modulation bandwidth of LED, which leads to a limited transmission rate of the VLC system. To solve this problem, hardware pre-equalization circuit is used in the VLC system. We design and use single and cascaded bridged-T amplitude equalizers. By combining the orthogonal frequency division multiplexing (OFDM) technology, the VLC system's modulation bandwidth and transmission rate can be improved efficiently.
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