Passive Optical Identifiers for VLC-Based Indoor Positioning Systems: Design, Hardware Simulation, and Performance Analysis

Indoor positioning systems (IPSs) based on visible light communication (VLC) shall be at the forefront of indoor localization technology in the near future. However, the existing VLC-based IPSs employ active devices that consume power and are costly. We develop a novel VLC-based IPS that circumvents the requirement of active devices by using the proposed optical identification algorithm, thereby enabling the IPS to be highly scalable, robust, energy efficient, inexpensive, and flexible. To implement this algorithm, we use a wavelength-sensitive receiver whose working is validated by hardware simulations. Another novel feature of our work is the design of a passive optical identifier that consists of a unique combination of optical reflectors and is analogous to a radio frequency identifier tag used for identification and tracking of different objects. We present an analysis of several practical aspects related to the physical realization of the proposed IPS, such as system scalability, target mobility, system reliability, algorithmic complexity, and implementation cost. To analyze the system performance, we determine its spatial resolution and the positioning error for different grid sizes. We conclude that the proposed IPS benefits from a low value of positioning error (similar to 2-35 cm) and is also cost efficient.