Antenna Grounding Rings for Wireless Charging Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electronic devices with compact wireless circuitry face challenges in achieving efficient antenna performance across a wide range of frequencies due to interference and limited antenna volume, which can lead to reduced efficiency and bandwidth.
Innovation Solution
The implementation of antenna grounding ring structures formed from concentric ring-shaped traces on a flexible printed circuit, which couple antenna currents to the ground traces while blocking higher frequency signals, allowing the antenna to maximize volume and efficiency bandwidth without impairing wireless charging efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the antenna volume is increased to improve efficiency and bandwidth, then antenna performance is improved, but the device size and complexity increase
Solution Approach 1:
The patent extends the antenna grounding ring into a third dimension by wrapping it around the coil structure, transforming a planar grounding pattern into a three-dimensional configuration. This dimensional transition allows the antenna to achieve greater effective volume and efficiency bandwidth without proportionally increasing the overall device footprint, as the grounding ring utilizes vertical and lateral space around the coil rather than only horizontal plane area.
2Reliability
If the antenna grounding ring is extended to maximize antenna volume, then antenna efficiency bandwidth is improved, but wireless charging efficiency may be impaired
Solution Approach 1:
The patent applies local quality by creating non-uniform spacing of the grounding ring segments around the coil structure. Certain segments are positioned closer to the coil while others are farther away, allowing different regions of the grounding ring to serve different functions: segments closer to the coil provide better grounding for antenna operation, while segments farther away minimize interference with wireless charging magnetic field coupling. This localized variation in grounding ring properties optimizes both antenna efficiency and wireless charging performance simultaneously.
3Device complexity
If compact structures are used to reduce device size, then form factor is improved, but antenna efficiency and bandwidth are reduced
Solution Approach 1:
The patent implements the nested doll principle by placing the antenna grounding ring structure around the coil structure, with the grounding ring segments nested in the space between the coil and the device housing. This nested configuration allows the antenna grounding system to occupy otherwise unused three-dimensional space within the compact device, achieving extended antenna performance without increasing the external device dimensions. The grounding ring is effectively hidden within the existing device architecture.
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 enhances antenna efficiency and bandwidth by shorting antenna currents to the ground, reducing signal losses and maximizing the effective antenna volume, while maintaining wireless charging efficiency.
Implementation Method 1
Antenna currents at the first frequency may be coupled onto the ring-shaped traces by near-field capacitive coupling
Implementation Method 2
The coil structures may receive wireless charging signals at a second frequency that is less than the first frequency through the rear housing wall
Implementation Method 3
The antenna resonating element may transmit and receive radio-frequency signals at a first frequency through the rear housing wall
Data Source
AI summary
An electronic device may include an antenna element, coil, sensor board, and grounding ring structures. The coil may receive wireless charging signals through the grounding ring structures. The grounding ring structures may include concentric ring-shaped traces separated by at least one gap. The ring-shaped traces and gaps may configure the grounding ring structures to short antenna currents at relatively high frequencies from the antenna element to a ground trace on the sensor board while blocking currents at relatively low frequencies. The grounding ring structures may include conductive wings that increase capacitive coupling between the grounding ring structures and the antenna element. The grounding ring structures may be soldered to the antenna element. The antenna element and the grounding ring structures may be formed from traces patterned on the same substrate. The ground trace may form part of an antenna without substantially impairing wireless charging efficiency of the coil.