Vehicle Glass Antenna Phase Difference via Vertical Conductor Segmentation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In glass antennas for vehicles, it is challenging to achieve a large phase difference between antenna conductors when the feeding portions are close together, which limits the spatial diversity effect and antenna gain due to restricted placement and wiring constraints.
Innovation Solution
The design includes elongated antenna elements and partial elements that extend in specific directions to create a phase difference between the first and second antenna conductors, with the second antenna conductor not being directly connected to the defogger, allowing for increased phase difference and high antenna gains even when feeding portions are close.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If feeding portions are separated to increase phase difference, then spatial diversity effect is improved, but placement and wiring constraints are worsened
Solution Approach 1:
The patent transitions from separating feeding portions in the planar direction (which is constrained by vehicle specifications) to separating them in the vertical direction (thickness direction of the window glass). This dimensional change allows achieving the required phase difference without violating placement and wiring constraints in the horizontal plane.
Solution Approach 2:
The patent changes the separation parameter from horizontal distance to vertical distance (thickness direction). By controlling the vertical distance between the first and second feeding portions, the phase difference is adjusted while maintaining horizontal placement within constraint limits.
2Reliability
If antenna conductors are elongated to increase phase difference, then spatial diversity effect is improved, but antenna conductor length is increased
Solution Approach 1:
Instead of increasing antenna conductor length in the horizontal plane, the patent utilizes the vertical dimension (thickness direction of the window glass) to create phase difference. The elongation is directed toward the outer circumference in the thickness direction, converting a horizontal length problem into a vertical positioning solution.
Solution Approach 2:
The antenna conductor is divided into multiple elements (first element, second element, third element) with specific elongation directions. This segmentation allows precise control of the current path and phase difference without requiring excessive total conductor length.
Data Source
AI summary
A glass antenna for a vehicle that has a first element elongated in a first direction, a second element elongated in a second direction, a third element including first, second and third partial elements that are each elongated in specific directions, and a fourth element elongated in the second direction but detours the second element in the second direction.