Adaptive Reliable Receivers for Optical Wireless communication (ARROW)

用于光无线通信的自适应可靠接收器 (ARROW)

基本信息

批准号：
EP/R023123/1
负责人：
Majid Safari
金额：
$ 47.24万
依托单位：
University of Edinburgh
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2018
资助国家：
英国
起止时间：
2018 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=EP%2FR023123%2F1
关键词：
Adaptive Reliable Receivers Optical Wireless

项目摘要

The gradual shrinkage of cell sizes in mobile cellular networks and applying frequency reuse techniques has been the main approach to cope with the exponential growth of capacity demands over the last few decades. However, the outdoor deployment of 5G cells will require a large-scale expansion of the backhaul network. The most preferred backhaul solution is based on highly reliable and high-speed fibre optic links; however, their use is limited to a fraction of the current backhaul network because of overwhelming installation costs. Free space optical (FSO) communication is an attractive alternative solution that provides high-capacity but cost-effective wireless backhaul connectivity without interfering with radio frequency (RF) communication systems. However, despite decades of technological advances, FSO links still suffer from availability issues in the form of occasional long outages in adverse weather conditions. This is because classical high-speed FSO receivers such as avalanche photodiodes (APDs) may totally fail under low visibility weather conditions. The important question is, therefore, whether we can build high-speed atmospheric optical communication links that can reliably operate over all weather conditions while providing data rates beyond their RF counterparts. ARROW aims to address the question above by combining classical and quantum optical receptions to allow for adaptive operation of FSO receivers within a wide range of sensitivity levels while keeping high-speed communication. However, highly sensitive quantum detectors such as single photon avalanche diodes (SPADs) are not practically suitable for terrestrial FSO links as they can easily saturate at typically high irradiance levels experienced at such links while their bandwidth is limited by effects such as dead time. ARROW's hybrid receiver employs an APD along with a large array of SPADs integrated into a single chip. The large size of array effectively relaxes the saturation issue of the SPAD-based detector while allowing for spectrally efficient modulations that can significantly improve its achievable data rate. ARROW receivers will combine the functionality of the classical and quantum detectors using hard and soft optical switching and efficient digital signal processing to support adaptive operation based on the slow varying weather condition. In order to design efficient switching and signal processing, we will develop an accurate but tractable theoretical model that describes the hybrid channel in terms of different atmospheric effects (e.g., visibility and background light level) and their interaction with the hybrid receiver's characteristics (e.g., SPAD dead time, detectors field of view, and optical splitting ratio). Based on this model, a number of optical frontend designs and advanced modulation and joint coding schemes will be proposed to enhance both data rate and reliability of the receiver. Finally, the adaptive functionalities of the hybrid receiver will be experimentally demonstrated and validated. ARROW FSO receivers are expected to provide carrier grade availability for a wide range of practical link geometries and geographical locations.

移动细胞网络中细胞大小的逐渐收缩和应用频率重用技术是应对过去几十年来满足能力需求指数增长的主要方法。但是，5G单元的室外部署将需要大规模扩展回程网络。最优选的回程解决方案是基于高度可靠和高速光纤链接。但是，由于安装成本压倒性的安装成本，它们的使用仅限于当前回程网络的一小部分。自由空间光学（FSO）通信是一种有吸引力的替代解决方案，可提供高容量但具有成本效益的无线回程连接，而不会干扰射频（RF）通信系统。但是，尽管有数十年的技术进步，但在不利天气条件下，FSO链接仍以偶尔停电的形式遭受可用性问题。这是因为经典的高速FSO接收器（例如雪崩光电二极管（APD））在低可见性天气条件下可能完全失败。因此，重要的问题是，我们是否可以建立高速大气光学通信链接，这些链接可以在所有天气条件下可靠地运行，同时提供超出RF的数据速率。 Arrow的目的是通过结合经典和量子光学接收来解决上述问题，以使FSO接收器的自适应操作在广泛的敏感性水平范围内，同时保持高速通信。但是，高度敏感的量子检测器，例如单个光子雪崩二极管（SPADS）实际上不适合陆生FSO链路，因为它们在这些链路上通常会在典型的高辐照度水平上饱和，而其带宽受到诸如死时间之类的效果的限制。 Arrow的混合动力接收器以及将大量的Spads集成到单个芯片中。大型阵列有效地放松了基于SPAD的检测器的饱和问题，同时允许进行频谱高效的调制，从而可以显着提高其可实现的数据速率。箭头接收器将使用硬和柔软的光学开关以及有效的数字信号处理来结合经典检测器和量子检测器的功能，以基于慢变化的天气条件来支持自适应操作。为了设计有效的开关和信号处理，我们将开发出一个准确但可进行的理论模型，该模型用不同的大气效应（例如，可见性和背景光级别）来描述混合通道以及它们与混合接收器特征（例如， SPAD死亡时间，探测器视野和光学分裂比）。基于此模型，将提出许多光学前端设计以及高级调制和关节编码方案，以提高接收器的数据速率和可靠性。最后，将对混合接收器的自适应功能进行实验证明和验证。箭头FSO接收器有望为各种实用的链接几何和地理位置提供载体等级的可用性。