Tracking with RFID asynchronous measurements by particle filtering

This paper deals with the problem of real-time indoor tracking of tagged objects in Ultra High Frequency Radio Frequency Identification systems with asynchronous measurements. A new and more realistic model of the system is proposed, where the probability of detecting a tag by a reader is described by a function of both the distance and the angle between the tag and the reader´s antenna. The model also accounts for the possibility of a tag being in a dead-zone where the tag cannot be detected. For tracking, we propose the use of the particle filtering methodology that takes into account the asynchronous nature of the measurements. The parameters for modeling the resulting system are obtained from real-world experiments and the performance of the algorithm is shown by extensive computer simulations.