Relay Antenna with High-Capacitance Tuning for Compact RFID
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing radio frequency transponder devices, such as USB keys and smart cards, face inefficiencies due to small antenna surface areas and interference from electronic components, limiting their range and compliance with standards like ISO 14443-2, and are difficult to manufacture effectively.
Innovation Solution
A radio frequency transponder device with a relay antenna having a high capacitance value, integrated into the antenna as a component, is positioned around the transponder antenna to enhance efficiency and avoid interference, using a substrate with a specific layout to minimize size and maximize coupling surface area while meeting ISO 14443-2 standards.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the antenna surface area is increased to improve RF communication range and efficiency, then the communication range and efficiency are improved, but the device size increases which contradicts the compact USB device form factor
Solution Approach 1:
The relay antenna is positioned within or around the transponder antenna structure, nesting the RF communication function within the existing device footprint. This allows the relay antenna to contribute to communication efficiency without requiring additional external space, effectively solving the contradiction between improved RF performance and compact device size
2Adaptability or versatility
If electronic components and connectors are installed on the printed circuit surface to provide USB and RF functions, then the device functionality is improved, but these components disrupt RF communication and prevent compliance with ISO 14443-2 standard
Solution Approach 1:
The relay antenna is extracted as a separate functional element from the printed circuit board, positioned in a location where it does not interfere with electronic components. This separation removes the harmful interference effect while preserving both the USB functionality (through the transponder antenna) and RF communication capability (through the relay antenna), enabling compliance with ISO 14443-2 standard
3Reliability
If a relay antenna is offset from the USB key body to avoid interference and improve range, then RF communication performance is improved, but manufacturing complexity increases
Solution Approach 1:
The relay antenna is merged with the transponder antenna structure, with both antennas integrated into the same device housing and substrate. This combination simplifies manufacturing by reducing the number of separate components and assembly steps, while still maintaining the performance benefits of having a relay antenna positioned to avoid interference and improve communication range
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
The solution increases the range and efficiency of radio frequency communication, reduces interference from electronic components, and simplifies manufacturing by using a high-capacity relay antenna integrated into the device, achieving compliance with ISO 14443-2 standards and minimizing the device's footprint.
Implementation Method 1
a relay antenna (4c, 4d) generating an electromagnetic field
Implementation Method 2
at least one tuning capacitor (C) attached and connected on the relay antenna
Data Source
AI summary
The invention relates to a device (D2) comprising a relay antenna (4c, 4d), said relay antenna comprising at least one outer relay turn (Sp, Sep) connected to at least one tuning capacitor consisting of an outer component (C) mounted on and connected to the antenna. Said device is characterized in that the tuning capacitor has a value greater than or equal to about 35 pF for a tuning frequency of 13.56 MHz. The invention also relates to a radiofrequency communication device including the relay antenna and a related transponder, as well as to a production method.