In order to tackle the rapidly growing number of mobile devices and their expanding demands for Internet services, network convergence is envisaged to integrate different technology domains. For indoor wireless communications, one promising approach is to coordinate light fidelity (LiFi) and wireless fidelity (WiFi), namely hybrid LiFi and WiFi networks (HLWNets). This hybrid network combines the high-speed data transmission of LiFi and the ubiquitous coverage of WiFi. In this article, we present a survey-style introduction to HLWNets, starting with a framework of system design in the aspects of network architectures, cell deployments, multiple access and modulation schemes, illumination requirements and backhaul. Key performance metrics and recent achievements are then reviewed to demonstrate the superiority of HLWNets against stand-alone networks. Further, the unique challenges facing HLWNets are elaborated on key research topics including user behavior modeling, interference management, handover and load balancing. Moreover, the potential of HLWNets in the application areas is presented, exemplified by indoor positioning and physical layer security. Finally, the challenges and future research directions are discussed.

中文翻译：

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混合LiFi和WiFi网络：调查

为了解决快速增长的移动设备数量及其对Internet服务的不断增长的需求，设想将网络融合以集成不同的技术领域。对于室内无线通信，一种有前途的方法是协调光保真度（LiFi）和无线保真度（WiFi），即混合LiFi和WiFi网络（HLWNets）。这种混合网络结合了LiFi的高速数据传输和WiFi的无处不在的覆盖范围。在本文中，我们从网络体系结构，小区部署，多路访问和调制方案，照明要求和回程方面的系统设计框架入手，对HLWNets进行了概述式的介绍。然后，对关键性能指标和最近取得的成就进行了审查，以证明HLWNet相对于独立网络的优越性。此外，在主要研究主题上详细阐述了HLWNet面临的独特挑战，包括用户行为建模，干扰管理，切换和负载平衡。此外，还介绍了HLWNet在应用领域中的潜力，以室内定位和物理层安全性为例。最后，讨论了挑战和未来的研究方向。