Vehicle NFC Antenna Layout for Hand and Smartphone Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The integration of multiple electronic components in vehicle door handles for detecting hand movements and smartphone approaches results in increased dimensions and costs, and NFC detection is unreliable with smartphones having low metal content.
Innovation Solution
A movement detection device using a near field communication antenna with a unique layout of conductive metal strips forming combs, capable of generating variable capacitance, combined with measurement means to detect hand movements and smartphone approaches through impedance variations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple electronic components (capacitive sensors, NFC reader, microcontrollers) are integrated into the door handle for detecting hand movements and smartphone approaches, then detection functionality is improved, but device dimensions and manufacturing costs increase
Solution Approach 1:
The patent combines multiple detection functions (hand movement detection and smartphone approach detection) into a single NFC antenna system. The NFC antenna serves dual purposes: communicating with smartphones and detecting hand movements through impedance variations, eliminating the need for separate capacitive sensors and multiple microcontrollers.
Solution Approach 2:
The NFC antenna is designed to perform multiple functions simultaneously: it acts as both a communication antenna for NFC exchanges with smartphones and a detection sensor for hand movements. This multi-functionality reduces the overall component count while maintaining comprehensive detection capabilities.
2Adaptability or versatility
If traditional NFC detection is used for smartphones with low metal content, then communication functionality is maintained, but detection reliability deteriorates
Solution Approach 1:
The patent replaces traditional capacitive sensing mechanisms with NFC-based electromagnetic field detection. By using the NFC antenna's impedance variations caused by hand proximity, the system achieves reliable detection without relying on metal content in smartphones, thus maintaining compatibility with various smartphone types.
Solution Approach 2:
The system monitors changes in electrical parameters (impedance, resonance frequency) of the NFC antenna to detect hand movements. This parameter-based detection method is independent of smartphone metal content, ensuring reliable detection across different device types while maintaining NFC communication functionality.
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 provides reliable and cost-effective detection of hand movements and smartphone approaches, reducing component complexity and size, while enhancing detection reliability.
Implementation Method 1
a near field communication antenna configured for transmitting and receiving signals at a high frequency with a selected resonance of between 3 and 30 MHz
Implementation Method 2
said antenna comprising at least one winding which is prolonged continuously in the form of at least two sets of strips, a first set and a second set being connected in parallel with said antenna in such a way that said two sets each have a different variable capacitance and sensitivity
Implementation Method 3
said antenna being capable of generating a different variation of impedance on the approach of part of a user's body towards the first or second set
Implementation Method 4
means of measurement by the electromagnetic coupling to said antenna of a variation of impedance or of a variation of resonance frequency of said antenna, the measurement means having a series resonance frequency at the selected high resonance frequency
Data Source
AI summary
A device for detecting the movement of part of a user's body and/or the approach of a portable user device. The device placed on board a motor vehicle. The device includes: a near field communication antenna having a resonance frequency between 3 and 30 MHz, including at least one continuous winding in the form of at least two sets of strips, each having different variable capacitance and different sensitivity, connected in parallel with the antenna. The antenna generating a different variation of impedance on the approach of part of a user's body towards the first or second set; a device measures a variation of impedance of the antenna. The device has a high series resonance frequency and detects the approach of a portable user device or movement of the body part taking place consecutively in front of the first and then in front of the second set of strips.