Estimation Method for High-Speed Vehicle Identification With UHF RFID Systems

An estimation method for Ultra High Frequency (UHF) Radio Frequency Identification (RFID)-based vehicle identification systems is presented. It allows the estimation of the number of reads within certain bounds at arbitrary vehicle velocities without requiring the knowledge of all system parameters. Based on this, a formula to calculate the maximum identifiable velocity is derived. It is also shown how the uncertainties of the formulas can be minimized. For the verification of the estimation method, two high-speed scenarios are described; the vehicle identification on roads and railways. Simulations with electromagnetic (EM) models of transponders mounted on different vehicles are described for both scenarios. It turns out that the simulated number of reads lies within the estimated range. Furthermore, a comparison with measurement data from a test track is presented. Here a good agreement between measured and estimated numbers of reads can be observed. The measured data is also used for the calculation of the maximum vehicle identification which lies in the range from 475.00 km/h 591.67 km/h. This means that for vehicle identification scenarios similar to the test track no speed limit is needed.