Tracking individual travel behaviour using mobile phones without information from base stations

Data collection methods that use mobile phones have been developed for tracking, monitoring, and analyzing travel behaviour. Previous methods using a Personal Handy Phone System (PHS) assumed that the location data of base stations were known. This paper shows a positioning method for a mobile object when base station location data are unavailable. Instead of base stations, signal strength vectors (reference vectors) are observed at many places in a target area. Mobile objects also observe a signal strength vector (target vector). A similarity index of reference and target vectors is used to calculate the location of a mobile object. This method tracked the ambulatory behaviour of tourists in an urban setting.