An RFID Tag Antenna Tolerant to Mounting on Materials

Abstract

This paper presents a novel UHF RFID tag antenna for mass-retailed products. The tag is realized on low-cost material. The antenna is composed of two elements: a planar dipole-based antenna, matched with a small inductive coil. In particular, it is able to work when directly mounted on different materials. When the permittivity or the thickness of the material on which it is mounted changes, the antenna's impedance varies around a fixed impedance on the Smith chart. This impedance is close to the conjugate of the RFID chip's input impedance. The different mounting materials tested were cardboard, a paper block, plastic, wood, a bottle of tap water, and a glass bottle. The measurement results indicated a maximum range of eight meters for materials with a low permittivity, and a maximum range close to two meters for denser materials or materials with a higher permittivity.

The effect of lossy dielectric objects on a UHF RFID meander line antenna

“…When the RFID chip has complex impedance, the resonance condition is changed and an alternative matching technique is required. One common option is the "T match" [3], [5][6].…”

“…These investigations did not report the effect of the electrical properties on the f c . Meander line antennas are common in RFID applications [3][4][5][6], with the antenna performance optimized for different substrates by changing the thickness of the meander line antenna. Larger antenna bandwidth may solve this problem [7 -9].…”

Miniaturization of Robust UHF RFID Antennas for Use on Perishable Goods and Human Bodies

“…This results in a limited range due to the low antenna efficiency and poor RCS ratio between the on/off state during modulation. Several papers have already addressed this issue, for example, an RFID antenna for onbody applications [4], implantable antennas [13] and RFID tags on bottles of water [14]- [15]. Based on this and on results from our research, it is possible to define some common design guidelines for efficiency improvement of robust RFID antennas in case of complex environments: i.…”

“…Our concept provides a small footprint and an excellent performance on meat and water. [4], [5], [14], [15] Further improvements could be made by extending the bandwidth of the prototype tag by using an adaptive tuning technique as proposed in [19]. The non-linear tuning circuit can be integrated within the IC, ensuring a cost-effective solution.…”

Determination of Dielectric Property of Construction Material Products Using a Novel Rfid Sensor

“…RF tag performance is affected by many factors, including EM properties of objects near or in contact with tags [10,11]. In addition, Siden et al presented a concept by which pairs of ordinary RFID tags are exploited as remotely read moisture sensors [12].…”