To wireless fidelity and beyond — CAPTURE, extending indoor positioning systems

Abstract

Most of the current research into indoor localization has surrounded the problem of positioning accuracy, with attempts to solve this using a myriad of technologies and algorithms. One of the problems that seems to be somewhat overlooked is the issue of coverage in an indoor localization solution. The mostly unobstructed views of the Global Positioning System (GPS) which requires a mere 30 satellites to provide global coverage never had these problems. Unfortunately unobstructed views are not something that can be achieved in most indoor environments and economical as well as physical barriers can prevent the installation of an infrastructure to achieve total coverage. In this paper we propose a solution to this issue of indoor coverage by deploying a solution to extend the range of a positioning system - Cooperatively Applied Positioning Techniques Utilizing Range Extension (CAPTURE). CAPTURE provides a system to locate devices that cannot be reached by an in-house location based system. It presents a unique contribution to research in this field by offering the ability to utilize devices that currently know their location within a Location Based Solution (LBS), to help evaluate the position of unknown devices beyond the range capacity of the LBS. Effectively extending the locating distances of an Indoor LBS by utilizing the existing mobile infrastructure without the requirement for additional hardware. CAPTURE uses the Bluetooth radios on mobile devices to estimate the distance between devices, before inserting these range estimates into a trilateration algorithm to ascertain position. CAPTURE has been tested through experiments carried out in a real world environment, proving the capacity to provide a solution to the ranging issue.