Magnetic Field Shaping Technique for HF-RFID and NFC Systems

Abstract

In this paper, the magnetic field shaping technique using the magnetic field repeater for high frequency radio frequency identification (HF-RFID) system and nearfield communications (NFC) system is proposed. This technique aims to improve the communication area between HF-RFID or NFC reader and passive tag by changing the magnetic field distribution over the original HF-RFID or NFC reader antenna. The multiple rectangular loop resonators cooperating with low loss air variable capacitors are employed to construct the proposed magnetic field repeater. The proposed magnetic field repeater is installed on top of the original HF reader antenna without any direct connection to the original reader antenna. The HF-RFID reader for laundry application is chosen as an example to prove the concept and verify the performance. We found that the communication area between the tag and off-the-shelf HF-RFID reader is improved. The proposed technique is useful for antenna improvement of off-the-shelf HF-RFID system in many applications such as laundry application, product tacking, etc. where a short range with wide communication area are required. KeywordsHigh frequency (HF) radio frequency identification (RFID), magnetic field repeater, HF-RFID reader antenna, magnetic resonance technique

On the design and implementation of efficient antennas for high frequency‐radio frequency identification read/write devices

“…However, in cases such as longer range systems where larger loops must be used, field shaping techniques such as the use of so-called magnetic field repeaters could be employed. 23 Alternatively, in order to eliminate or correct flux dead zones, an array of smaller independent and appropriately distributed loops could be used rather than a single large coil. 24…”

Solid state resonant circuits and wireless electrical power propagation for mobile devices applications

“…Near Field Communication (NFC) is a technology that uses an inductive coupling technique oriented for mobile smart phone and operates at 13.56 MHz; it works via magnetic field induction and can transmit information in short distances up to a maximum rate of 424 Kbit per second. NFC systems are oriented to data exchange applications and usually used in mobile phones [8].…”

Wearable near‐field communication bracelet based on highly conductive graphene‐assembled films

“…1,2 This close-range technology enables the passive devices, such as NFC tags, to harvest the power required for operation from the near-field of an active device known as the reader through magnetic induction coupling. [3][4][5][6] Thus, no power supply is needed in these tags, reducing the manufacture cost. Since its first introduction in early 2000s, NFC has been widely used in identification, 7 tracking, 8 access control and contactless payment systems, [9][10][11] demonstrating a key role in bringing the Internet of Things (IoTs) to reality with unimaged applications emerging every day.…”

“…Among them, near‐field communication (NFC), is a radio frequency identification (RFID)‐based contactless communication technology which operates at a specific frequency of 13.56 MHz for close‐range communications always within a few centimeters, thus, provides more security and privacy than RFID 1,2 . This close‐range technology enables the passive devices, such as NFC tags, to harvest the power required for operation from the near‐field of an active device known as the reader through magnetic induction coupling 3‐6 . Thus, no power supply is needed in these tags, reducing the manufacture cost.…”