Received: 13 March 2018 Revised: 22 June 2018 Accepted: 10 July 2018 DOI: 10.1002/ett.3498 SPECIAL ISSUE ARTICLE Implementation of a VLC-based indoor localization system E. Torres-Zapata 1 J. M. Luna-Rivera 1 R. Perez-Jimenez 2 V. Guerra 2 J. Rabadan 2 J. Rufo 2 C. A. Gutierrez 1 1 Facultad de Ciencias, Universidad Autónoma de San Luis Potosí, San Luis Potosí, México 2 IDeTIC, Universidad de las Palmas de Gran Canaria, Las Palmas, Gran Canaria, Spain Correspondence J. M. Luna-Rivera, Facultad de Ciencias, UASLP, Av. Salvador Nava s/n, Zona Universitaria, C.P. 78290, San Luis Potosí, México. Email: mlr@uaslp.mx Present Address Av. Salvador Nava s/n, Zona Universitaria, C.P. 78290, San Luis Potosí, S.L.P., México Funding information CONACYT, Mexico, Grant/Award Number: 236188; Spanish Government (Economy, Industry and Competitiveness Ministry), Grant/Award Number: TEC2013-47682-C2-1 Abstract Nowadays, with the incursion of solid state lighting technology in our daily life, visible light communication (VLC) systems are becoming more important. This fact has generated a lot of attention on VLC to provide solutions on mul- tiple applications where this technology can be exploited. At the same time, the growing of automation processes has created the necessity of knowing the localization of different objects and devices. Indoor localization based on radio frequency signals is one of the most used techniques (Wi-Fi, Bluetooth, UWB, RFID, etc); however, VLC is a new and interesting method, which is gaining enormous research attention. Moreover, there are environments where the use of RF technologies is restricted or even prohibited. In such cases, VLC tech- nology becomes an interesting alternative to solve this problem. In this paper, we design and implement a novel VLC-based indoor localization system that combines the application of a VLC scheme for downlink and an ultrasonic com- munication for the uplink. Practical localization experiments are carried out in an actual office room environment, and results show a localization accuracy of 4 cm on average for direct links and 10 cm for indirect links. 1 INTRODUCTION In recent years, the rise of mobile devices and the excessive demand for data have caused the saturation of the electro- magnetic spectrum. This trend has led to the search for new communication alternatives to meet such demands, among these options is the use of an innovative mean of transmitting data called visible light communication (VLC). Moreover, VLC technology adopts the visible light between 375 and 780 nm to transmit data wirelessly. Because LEDs are solid-state lighting devices, they can be modulated at a high speed, which avoids to be detected by the human eye and enabling it for the dual purpose of data communication and illumination simultaneously. Inherent features of VLC include energy efficiency, high bandwidth available, not being affected by electromagnetic interference, as well as having a robust secu- rity. These factors have led to significant interest in VLC with the potential to provide a contribution to the short-range communication demands. Potential applications of VLC include vehicle-to-vehicle communication, consumer electron- ics, healthcare, home and building automation, robots in hospitals, underwater communication, information displayed on sign boards, etc. 1 Location-based services have particularly become a very important topic for indoor wireless communications. With the incursion more and more of automated processes, as well as the appearance of the Internet of Things, there is a growing demand for location awareness in many Internet of Things applications. The most extended localization technology is the Global Positioning System, which allows determining the location of an object with a standard accuracy up to a few meters. Trans Emerging Tel Tech. 2018;e3498. wileyonlinelibrary.com/journal/ett © 2018 John Wiley & Sons, Ltd. 1 of 12 https://doi.org/10.1002/ett.3498