Dual-Use Antenna for Wireless and Capacitive Sensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The integration of capacitive sensors and wireless communication components in a single housing for vehicle door unlocking systems faces space constraints, limiting the physical space available for both functionalities.
Innovation Solution
A communication device with a wireless communication circuit, a capacitive sensor circuit, and an antenna that doubles for both wireless signal transmission/reception and capacitance detection, utilizing high-pass and low-pass filters to separate AC and DC signals, allowing for parallel operation without interference, and is designed to be integrated into a gripping portion like a door handle.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If both capacitive sensor and wireless communication components are integrated in a single housing, then device functionality is improved, but physical space requirements increase
Solution Approach 1:
The antenna structure is designed to serve dual purposes: it functions as both a wireless communication antenna and a capacitive sensor for proximity detection. By making the antenna itself capacitive, the patent eliminates the need for separate sensor components, thereby integrating multiple functions into a single structure and reducing overall device volume while maintaining full functionality.
2Measurement precision
If capacitive sensor and wireless communication circuit operate simultaneously, then detection accuracy is improved, but signal interference increases
Solution Approach 1:
The patent introduces a coupling circuit as an intermediary component between the antenna and the capacitive sensor circuit. This coupling circuit selectively couples the antenna to either the wireless communication circuit or the capacitive sensor circuit based on operational mode, thereby mediating signal transmission and preventing direct interference between the two systems while maintaining detection accuracy.
3Device complexity
If antenna is used for both wireless communication and capacitance detection, then device complexity is reduced, but signal separation difficulty increases
Solution Approach 1:
The patent employs periodic switching between wireless communication mode and capacitive sensing mode through the coupling circuit. By alternating between these modes in time-division multiplexing fashion, the system allows the antenna to serve both functions without requiring complex simultaneous signal separation, thereby reducing device complexity while managing signal interference through temporal separation.
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
Enables a compact device that performs wireless communication and proximity detection, enhancing security by allowing secure vehicle door unlocking while minimizing space requirements.
Implementation Method 1
an antenna configured to be used for both transmitting/receiving a wireless signal conforming to the specific communication and detecting the capacitance
Implementation Method 2
a high-pass filter disposed between the wireless communication circuit and the antenna
Implementation Method 3
a low-pass filter disposed between the capacitive sensor circuit and the antenna
Data Source
AI summary
There is provided a communication device comprising: a wireless communication circuit configured to control wireless communication with a portable device in conformity with a specific communication standard; a capacitive sensor circuit configured to detect proximity of an object on a basis of a change in capacitance; an antenna configured to be used for both transmitting/receiving a wireless signal conforming to the specific communication and detecting the capacitance; a high-pass filter disposed between the wireless communication circuit and the antenna; and a low-pass filter disposed between the capacitive sensor circuit and the antenna, wherein the communication device is configured to be disposed in a gripping portion to be gripped by a user carrying the portable device.