GRAIL: a general purpose localization system

Purpose - The purpose of this paper is to describe a general purpose localization system, GRAIL. GRAIL provides real-time, adaptable, indoor localization for wireless devices. Design/methodology/approach - In order to localize as diverse a set of devices as possible, GRAIL utilizes a centralized, anchor-based approach. GRAIL defines an abstract data model for various system components to support different physical modalities. The scalable architecture of GRAIL provides maximum flexibility to integrate various localization algorithms. Findings - The authors show through real deployments that GRAIL functions over a variety of physical modalities, networks, and algorithms. Further, the authors found that a centralized solution has critical advantages over distributed implementations for handling privacy concerns. Originality/value - A key contribution of this system is its universal approach: it can integrate different hardware and software capabilities within a single localization framework. The deployment of such a system in academic and research environments allows researchers to explore issues beyond algorithms and investigate effects in real deployments.