Analysis of Dead Zone of RFID System

Quadruple‐feed beam‐controlled antenna array for the localisations of ultra‐high‐frequency radio‐frequency identification tags

“…Thus, the location of antenna element(s) for the RFID reader has to be carefully positioned and/or tuned by experts to optimise performance in settings such as, for example, a factory floor, a production facility or a commercial establishment. Particularly, in case of the item-level tagging at the retail market with densely placed items, the dead zones (or blind spots) where the tag is non-responsive can be created because of the multi-path fading [13,14]. Furthermore, the indoor RFID localisation system can compute accurate localisation of the scattered RFID tags based on phase difference [15], a zero-phase-shift line [16] or received signal strength [17].…”

Selectable sectoral antenna array using a quadruple feeding network for item‐level tagging in UHF RFID applications

“…The main reason for this is due to the fact that the size of the antenna is determined by the fundamental laws of physics. The antenna size with respect to the wavelength will have the preponderant influence on the radiation characteristics [1]. An antenna is used to transform a guided wave into a radiated one and vice versa.…”

“…In particular, the multipath propagations and reflection of reader transmitted signals can create dead zones or blind spots where RFID tag is nonresponsive. As the existence of the dead zones which lie inside of the operating reading range deteriorates the reliable identification performance of the RFID system, the problem regarding the dead zone has come to occupy an important position in UHF RFID systems .…”

“…Several papers have been published on this study. Using the plane wave incidence based on the Method of Moment, the numerical analysis and measurements of dead zone of RFID system were examined in 2006 by . The cause of the dead zone was analyzed in terms of impedance matching in RFID tags.…”

Analysis of Dead Zone by Mathematical Methods

“…Many papers have done relative works on this topic. By analyzing the electric field distribution and current distribution when the tag is located near the conduction plate to explain the dead zone [1]; By investigating in experimental and simulation ways to explain the blind spot [2]; Tag has a non-monotonic variation of the transmission coefficient with absorbed power to explain the dead zone [3] etc. In this paper, we will explain the reasons for creation of dead zones and then analyze the reasons with mathematics methods.…”