Calibration-less Indoor Location Systems Based on Wireless Sensors

In case of a crisis event, it is the responsibility of public and government authorities to manage the response operations. Positioning is a crucial task when managing emergency, which aims at estimating the positions of the first responders that act on the crisis site. On the other hand, the radio-based positioning solutions require a process of site survey, in which radio signatures have to be collected and stored in a radio map for further comparison and matching. Site survey involves intensive manual effort and time, which is no feasible during the crisis event. This paper proposes an approach for rapid site survey of the considered area. A specific tool has been developed to draw the site topography and to define the radio map generated by the wireless sensors located in the considered area, by using an accurate signal attenuation model. Experiment results show that the proposed solution can achieve a position accuracy that can be considered acceptable in the context of the rescuers localization even without a site survey activity.