Characterization of the RFID deterministic path loss in manufacturing environments

Results of measurement campaigns carried out aiming at the development of a tool for design, deployment, and analysis of RFID systems are shown. Particularly, in this paper, the radio path loss from an RFID reader towards the test tag and back to the reader is characterized at the 915 MHz band. The path loss is estimated based on the received signal strength measured at the reader, for different reader-tag separation distances and different antenna tag heights. Several propagation scenarios have been considered, including outdoor and indoor environments for which an extensive number of typical real manufacturing plants have been chosen. The field data are then compared to a proposed novel, improved version of the classical 2-ray path loss model, adjusted to also include the non-omnidirectional antenna radiation patterns at the reader and tag sides. To the best of the authors´ knowledge, the scope and reach of the measurements as well as the proposed path loss model are new.