Vehicle Antenna Capacitor Part Series Segmentation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing antenna devices face challenges in consistently setting the additional capacitor, leading to variations in transmission and reception efficiency due to capacitance changes based on the thickness of the dielectric substrate and size of the solder land, resulting in inadequate performance.
Innovation Solution
The antenna device incorporates a capacitor part electrically connected to the antenna element via a metal leg, featuring multiple capacitors connected in series to stabilize electrostatic capacitance, with the capacitors placed on separate areas of the substrate to minimize parasitic capacitance and ground pattern interference, allowing for precise capacitance setting.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the additional capacitor is formed using the dielectric substrate and solder land, then the antenna device can be manufactured, but the electrostatic capacitance varies due to thickness and size variations, resulting in insufficient transmission and reception performance
Solution Approach 1:
The capacitor part is segmented into multiple discrete capacitors (first capacitor and second capacitor) connected in series, rather than forming a single capacitor using the dielectric substrate and solder land. This segmentation allows for more precise control of the total capacitance value while maintaining ease of manufacture, as discrete capacitors can be selected with tight tolerance values.
Solution Approach 2:
A dedicated capacitor part is introduced as an intermediary component between the antenna element and the ground conductor, rather than relying on the dielectric substrate and solder land to form the capacitor. This intermediary capacitor part provides stable and precise electrostatic capacitance that is not affected by variations in substrate thickness or solder land size.
2Manufacturing precision
If the capacitor part includes multiple capacitors connected in series, then the electrostatic capacitance can be accurately set and variations suppressed, but the device complexity increases
Solution Approach 1:
Multiple capacitors (first capacitor and second capacitor) are merged by connecting them in series to form a single capacitor part with a combined electrostatic capacitance. This merging approach allows for precise capacitance control through the series combination formula (1/C_total = 1/C1 + 1/C2), while the entire capacitor part is integrated onto the dielectric substrate, minimizing the increase in device complexity.
3Manufacturing precision
If the capacitor part is provided on a separate area from the ground pattern, then parasitic capacitance and ground pattern interference are reduced, but the area required on the substrate increases
Solution Approach 1:
The capacitor part is placed in a specific local area (second area) of the dielectric substrate that is distinct from the ground pattern area (first area). This local quality differentiation ensures that the capacitor part is positioned where it will not be affected by the ground pattern, thereby reducing parasitic capacitance and interference, while the overall substrate area increase is minimized by efficient spatial arrangement.
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 configuration reduces variations in electrostatic capacitance, enhancing the antenna's ability to accurately set the additional capacitor, thereby improving transmission and reception efficiency and maintaining performance across different frequency bands.
Implementation Method 1
a capacitor part electrically connected to the antenna element, in which the capacitor part is electrically connected to the metal plate part via the metal leg part and includes two or more capacitors connected in series
Implementation Method 2
an electrostatic capacitance of the capacitor part to be connected to the antenna element is determined by the capacitors therein
Data Source
AI summary
An antenna device is provided for a vehicle. The antenna device includes a substrate, an antenna element and a capacitor part. The substrate includes a pair of main surfaces which face opposite sides each other. The antenna element includes a metal plate part which is disposed over and separated from one of the main surfaces, and a metal leg part which extends from the metal plate part toward the substrate. The capacitor part is electrically connected to the metal plate part through the metal leg part and includes two or more capacitors connected in series.