Pervasive Indoor Outdoor Detection System

Nowadays a growing number of mobile applications are centered around the user's location. The location information not only include physical coordinates but also logical locations. Indoor/outdoor is an important primitive logical location information, it can be used by many location-based and context-aware applications. In this paper, we extract some consistent physical features of magnetism and human activity using several lightweight sensors. And based on these features we present a pervasive, accurate and fast indoor outdoor detection system, which provides the indoor/outdoor information to upper applications. We prototype the system on Android mobile phones and evaluate the system comprehensively with data collected from 5 users' daily life during one month period, employing different phone models. The system achieves 93% accuracy rate and the consumption is between 3mW and 9mW.