Movable Coupling Frame Layout for Metal RFID Payment Objects
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
RFID devices, particularly those integrated into metal jewelry and wearables, face challenges in maintaining effective communication due to the attenuating effects of metal surfaces, which hinder the electromagnetic field pickup by passive transponder devices operating at 13.56 MHz frequencies.
Innovation Solution
Incorporating a coupling frame with a slit into the RFID device, allowing for capacitive coupling with a contactless reader by positioning the slit to overlap the module antenna, thereby enhancing or disabling communication as needed, and using a movable coupling frame to optimize communication range and power delivery.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a passive transponder device is integrated into metal jewelry or wearables, then the device can be incorporated into payment objects and wearables, but the metal surfaces attenuate the electromagnetic field and hinder communication with contactless readers
Solution Approach 1:
A coupling frame is introduced as an intermediary component between the metal housing and the transponder chip module. The coupling frame includes a capacitive coupling element that mediates the electromagnetic field interaction, allowing the transponder to communicate effectively through or near metal surfaces without direct metal-to-antenna contact that would cause attenuation.
Solution Approach 2:
The device is segmented into distinct functional components: the metal housing, the coupling frame with capacitive coupling element, and the transponder chip module. This segmentation allows each component to perform its specific function - the metal housing provides structural integrity and aesthetic value, while the coupling frame handles the electromagnetic coupling, and the transponder performs data storage and processing.
2Reliability
If a coupling frame with slit is used to enable capacitive coupling, then communication range and power delivery are enhanced, but the device complexity increases
Solution Approach 1:
The coupling frame is designed with movable elements that can dynamically adjust their position or orientation. This dynamic capability allows the capacitive coupling element to be positioned optimally for different communication scenarios, enhancing read/write range and power delivery while maintaining a relatively simple overall structure that can be implemented using standard mechanical components.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution enables improved communication and power delivery to the RFID chip, enhancing the read/write range and functionality of RFID devices in metal-containing payment objects and wearables by selectively enabling or disabling contactless communication.
Implementation Method 1
Incorporating a coupling frame with a slit into the RFID device, allowing for capacitive coupling with a contactless reader by positioning the slit to overlap the module antenna
Implementation Method 2
passive transponder devices operating at 13.56 MHz frequencies
Data Source
AI summary
RFID devices comprising (i) a transponder chip module (TCM) having an RFIC chip (IC) and a module antenna (MA), and (ii) a coupling frame (CF) having an electrical discontinuity comprising a slit (S) or non-conductive stripe (NCS). The coupling frame may be disposed closely adjacent the transponder chip module so that the slit overlaps the module antenna. The RFID device may be a payment object such as a jewelry item having a metal component modified with a slit (S) to function as a coupling frame. The coupling frame may be moved (such as rotated) to position the slit to selectively overlap the module antennas (MA) of one or more transponder chip modules (TCM-1, TCM-2) disposed in the payment object, thereby selectively enhancing (including enabling) contactless communication between a given transponder chip module in the payment object and another RFID device such as an external contactless reader. The coupling frame may be tubular. A card body construction for a metal smart card is disclosed.