Beam-steered infrared light can provide ultra-high wireless capacity to individual user devices for indoor communication systems. The optical beams used to obtain such high capacities are relatively narrow with the average beam divergence of less than 2.55°, hence an accurate localization system to pinpoint multiple user devices at the same time is required. In addition, an indoor communication should provide mobile coverage to all users, therefore a dynamic and fast localization equipped with a capability of conveying the channel link status of the user devices to optical access points is necessary. In this work, we propose a vision-based technique to simultaneously localize the user devices in a room. A LED-tag system positioned around a photodetector enables the access points to recognize active users. A localization accuracy of 0.018° is achieved within milliseconds. Furthermore, taking advantage of this vision-based system, upstream signaling for channel status information is proposed using M-ary intensity modulation. Experimental results show that an upstream signaling rate of 2.4kbps can be achieved with our simple and low-cost prototype, enabling >10Gbit/s link per user.

中文翻译：

---

聚束红外光通信系统的用户本地化和上行信令

光束控制的红外光可以为室内通信系统的各个用户设备提供超高的无线容量。用于获得如此高容量的光束相对较窄，平均光束发散度小于2.55°，因此需要一种精确的定位系统来同时精确定位多个用户设备。另外，室内通信应向所有用户提供移动覆盖，因此，具有将用户设备的信道链路状态传达到光接入点的能力的动态快速定位是必要的。在这项工作中，我们提出了一种基于视觉的技术来同时定位房间中的用户设备。位于光电探测器周围的LED标签系统使访问点能够识别活动用户。定位精度为0。在几毫秒内达到018°。此外，利用此基于视觉的系统，提出了使用Mary强度调制的信道状态信息的上行信令。实验结果表明，使用我们的简单且低成本的原型可以实现2.4kbps的上行信令速率，从而使每个用户的链路速率> 10Gbit / s。