An improved channel model for passive UHF RFID systems

Abstract

For preliminary performance evaluation of an UHF RFID system, it is important to have a simple and fast simulation environment available. The calculation of the receive signal power at arbitrary positions of a predefined environment should be fast and accurate to find dead zones where tags cannot be read although they are well within the reader's communication range. Changes in the system configuration or the simulated environment must be easy to implement. In this paper we use the simple and fast calculable UHF RFID channel model from [1] and improve it in different aspects to better fit the real indoor multipath signal propagation. A comparison between measurements and simulations shows that our model delivers 1.8 dB better performance in average than the original model, while adding only little complexity and computing time. Using our simulation environment, it is easy and fast to find dead zones for arbitrary system setups.

An Experimental Study on the Feasibility of a Frequency Diverse UHF RFID System

“…A similar model for UHF RFID, treating one direct wave and one wave reflected at the floor, is discussed in [27]. However, other authors find that a two ray model is not sufficient to be representative for a real environment [28]. In [7] a detailed analysis of multipath fading in UHF RFID systems is presented.…”

“…Besides an analytical treatment, this work also includes simulations of the field strength and a comparison to real read rate measurements. Another work by Cremer et al shows an improved analytical model to predict multipath fading [28]. Also a comparison of the model with measurements at two different frequencies is performed.…”

On energy harvesting for augmented tags

“…The idea of the sensor-tag approach is to associate new tag information capture capabilities while still enjoying the identification functionality and obviously, also the remote power supply and wireless transmission. A wide variety of RFID Sensors have been demonstrated in the literature, among them sensors for temperature [3,4], pressure [5], humidity [6,7], deformation [8], crack width [9], curvature monitoring [10], Open/Close [11], chemical [12], food quality [13], etc. The previous references give some examples of the cited functionalities, but the list is not exhaustive.…”