In the coming Industry 4.0, there is a long-standing challenge to transfer real-time broadband data (e.g., video monitoring data) among machines. Optical wireless communication (OWC), which can easily carry tens of gigabit/s data, is a promising technology but suffering from non-line-of-sight (NLOS) limitation. In the NLOS scenario, the power of diffused light is heavily attenuated while the diffuse-induced multi-path effect suppresses the band-width of received signals. In this article, the diffuse light reflected off a rough surface (e.g., ceilings or walls) can be focused at a target receiver with an average 18-dB-power-enhancement. A record 40-Gbit/s >80°-coverage beam-steered NLOS OWC system enabled by the proposed diffuse reflection focusing (DRF) is experimentally demonstrated over a diffused 25-cm free-space link. The fast-focusing transmission matrix (TM) algorithm, which takes only 513 iterations to do the focusing, is introduced to make the DRF technique more practical for daily applications. The low-cost intensity-modulation/direct-detection (IM-DD) transmission scheme and the simple on-off keying (OOK) signal are selected to support low-cost applications. All these features exhibit its great potential for high-speed indoor wireless communications, especially in the scenarios of Industry 4.0.

中文翻译：

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适用于工业 4.0 的宽覆盖波束控制 40-Gbit/s 非视距光学无线连接

在即将到来的工业 4.0 中，在机器之间传输实时宽带数据（例如视频监控数据）是一个长期存在的挑战。光无线通信 (OWC) 可以轻松承载数十千兆位/秒的数据，是一项很有前途的技术，但受到非视距 (NLOS) 限制。在 NLOS 场景中，漫射光的功率会严重衰减，而漫射引起的多径效应会抑制接收信号的带宽。在本文中，从粗糙表面（例如天花板或墙壁）反射的漫射光可以集中在目标接收器上，平均功率增强为 18 dB。通过所提议的漫反射聚焦 (DRF) 实现的创纪录的 40-Gbit/s > 80° 覆盖光束控制 NLOS OWC 系统在漫反射 25 厘米自由空间链路上进行了实验证明。引入快速聚焦传输矩阵（TM）算法，只需513次迭代即可完成聚焦，使DRF技术在日常应用中更加实用。选择低成本的强度调制/直接检测 (IM-DD) 传输方案和简单的开关键控 (OOK) 信号来支持低成本应用。所有这些特性都展现了其在高速室内无线通信方面的巨大潜力，尤其是在工业 4.0 的场景中。