A single sided dual-antenna structure for UHF RFID tag applications

Abstract

In this article, a dual-antenna structure is presented for UHF RFID tag. The proposed structure is made of two L-shaped strip antennas along with a cross-shaped slot loaded patch. One antenna is exclusively used for receiving and harvesting full energy with complex conjugate of tag chip, whereas another used as backscatter to enhance maximum differential radar cross section with purely real input impedance, which results in the enhancement of read range. Further, electromagnetic band gap structure is used around the dual-antenna structure to increase the gain which results in improved read range. The proposed antennas are fabricated and the S-parameters are measured with the help of differential probe technique. Simulation and measurement results are found in good agreement. The performance of the proposed antenna is also investigated when it placed on different materials such as metal, wood, glass, and plastic. The study shows that the read range of antenna increases considerably when it is mounted on a metallic surface, while the maximum performance is observed when the antenna is attached on a glass surface with highest relative permittivity. V C 2015 Wiley Periodicals, Inc. Int J RF and Microwave CAE 25:619-628, 2015.

A chipless RFID tag for smart temporal applications

“…The power of the received signal P RX is given by the following equation where, P TX is the transmitted power, G TX and G RX are the gain of the transmitter and receiver, respectively, λ is the operating wavelength, r is the distance between tag and reader . In Equation , the term (λ/4 rπ ) is referred to as the free‐space loss factor and takes losses due to spherical spreading of energy.…”

“…RFID was introduced in World War II to distinguish between friend and enemy aircraft . Currently, RFID technology is extensively deployed in numerous applications such as transportation, item tracking, and security, industries . It is estimated that the demand of RFID tags will reach up to 75 trillion units per year by 2019 .…”

Miniaturized decoupled slotted patch RFID tag antennas for wearable health care

“…The performance parameters discussed above suffer significant degradation in applications that involve human body as a platform . Antenna designs with the ground plane are observed to be robust to the electromagnetically complex environments such as metals and human body . One such structure proposed in Ref.…”

“…25 Antenna designs with the ground plane are observed to be robust to the electromagnetically complex environments such as metals and human body. 23,26,27 One such structure proposed in Ref. 28 is based on etched slots in a microstrip patch.…”

UHR RFID ring resonator-based tag antenna with photonic bandgap structure for metallic objects

“…The ability of placing modern RFID tag antennas on metallic objects has been investigated [4][5][6][7][8][9][10][11]. The most challenging issue is designing tag antenna for metallic objects with high gain, little reflection coefficient and small size.…”