Indoor Navigation With Virtual Graph Representation: Exploiting Peak Intensities of Unmodulated Luminaries

The ubiquitous luminaries provide a new dimension for indoor navigation, as they are often well-structured and the visible light is reliable for its multipath-free nature. However, existing visible light-based technologies, which are generally frequency-based, require the modulation on light sources, modification to the device, or mounting extra devices. The combination of the cost-extensive floor map and the localization system with constraints on customized hardwares for capturing the flashing frequencies, no doubt, hinders the deployment of indoor navigation systems at scale in, nowadays, smart cities. In this paper, we provide a new perspective of indoor navigation on top of the virtual graph representation. The main idea of our proposed navigation system, named PILOT, stems from exploiting the peak intensities of ubiquitous unmodulated luminaries. In PILOT, the pedestrian paths with enriched sensory data are organically integrated to derive a meaningful graph, where each vertex corresponds to a light source and pairwise adjacent vertices (or light sources) form an edge with a computed length and direction. The graph, then, serves as a global reference frame for indoor navigation while avoiding the usage of pre-deployed floor maps, localization systems, or additional hardwares. We have implemented a prototype of PILOT on the Android platform, and extensive experiments in typical indoor environments demonstrate its effectiveness and efficiency.

I. Introduction

Offering indoor navigation services is of crucial importance, which is a common welfare in complex indoor environments for many involved users such as shop owners and shoppers in smart cities with ubiquitous smart urban infrastructures. Recently, visible light has become a key enabler for indoor navigation, owing to its high reliability immune from multi-path and the light sources are ubiquitous and well-structured in indoor environments. For instance, Carrefour supermarket in Lille, France, uses the Philips connected lighting system to facilitate customers’ navigation and triggers aisle-specific special offers (e.g., discounts/promotions) around them, which indeed helps shoppers save shopping time and expenditure while in return increases the sales volume. The potential huge market of mobile industry naturally attracts extensive studies on location-based services (LBS) [1] and LBS related applications such as navigation, location-aware marketing [2], social recommendation [3], [4], and privacy-protecting [5].¹

http://www.lighting.philips.com/main/systems/connected-lighting.html.