Characterization of a geometrical wireless signal propagation model for indoor ranging techniques

Wireless positioning systems are interesting for a variety of indoor applications such as security, home automation and ambient assisted living (AAL) services. Unfortunately, the accuracy of distance measurement techniques based on short-range wireless communication transceivers is generally quite poor, mainly because of multipath propagation phenomena. In this paper an analytical model describing the effect of multipath propagation on received signal power is presented. In particular, both the case of pure sine wave indoor propagation and the more involved scenario based on IEEE 802.15.4 Offset Quadrature Phase-Shift keying (OQPSK) signals are analyzed. Several experimental results collected in an anechoic chamber confirm a reasonably good agreement with the proposed model, thus paving the way to new strategies to improve indoor ranging accuracy based on wireless techniques.