Modeling of the RSS Uncertainty for RSS-Based Outdoor Localization and Tracking Applications in Wireless Sensor Networks

In the present study, we investigate the variability of the RF signal, measured as Received Signal Strength (RSS), in outdoor unobstructed environment aiming at modeling of the RSS uncertainty for the needs of the outdoor RSS-based localization and tracking applications. The modeling approach is based on determining empirically the relation between the RSS mean value and the RSS data deviation. Two modeling tasks are performed, namely RSS-static and RSS-mobile, representing the situation when the localized sensor node is immobile and when it is mobile, i.e., attached to a person. The performed simulation of RSS variance shows good correspondence to the measured variance, which validates the proposed approach.