Real-World Efficacy of an Infrastructure-Free Geomagnetic Indoor Positioning System

Abstract

Infrastructure-free Indoor Positioning Systems (IPS) are a relatively new advancement in the indoor localisation area. Traditionally, IPS's require a certain amount of dedicated infrastructure within a building to position a device accurately. There are now companies offering infrastructure-free IPS that claim they can obtain sub-metre accuracy. Some IPS's also claim to use geomagnetic positioning to achieve this accuracy. The aim here is to investigate the accuracy of an infrastructure-free IPS which offers geomagnetic positioning techniques. We explain its accuracy, what may negatively affect the accuracy of the system and to what extent are geomagnetic positioning techniques being used. An Android mobile application was developed with the primary purpose of investigating the accuracy of the IPS under various conditions. We found that the IPS at the beginning was three times more accurate than GPS and ten times more accurate at the end. The IPS was more responsive and more accurate on a device that had a magnetometer but accuracy dropped considerably when the internet connection is lost. Also, wet weather specifically impacted negatively on the accuracy.