Switchable Antenna Radiation Paths for SAR Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current electronic devices face challenges in minimizing Specific Absorption Rate (SAR) when rotated, leading to potential harm to the human body and communication interruptions due to misjudgment by proximity sensors or reduced emission power.
Innovation Solution
An electronic apparatus with multiple radiation paths and a switching element, controlled by a control unit and orientation sensor, selectively switches the radiation path to avoid SAR-related issues during rotation, ensuring continuous communication performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a proximity sensor is used to detect the distance between the electronic apparatus and the human body, then the SAR can be reduced, but the user experience deteriorates due to misjudgment causing normal operation to be interrupted
Solution Approach 1:
The antenna body is divided into multiple radiation paths (first radiation path and second radiation path) positioned at different locations. Instead of using a single antenna that may cause high SAR when close to the body, the system segments the radiation function across multiple paths, allowing selective activation based on orientation to minimize SAR exposure while maintaining operational continuity.
Solution Approach 2:
The system dynamically switches between different radiation paths based on the rotation orientation of the electronic apparatus. The control unit receives orientation information and selectively activates appropriate radiation paths in real-time, making the antenna system adaptive to changing orientations and body proximity conditions without interrupting normal operation.
2Object-affected harmful factors
If emission power is reduced to lower SAR, then the harmful effects to the human body are decreased, but communication performance deteriorates due to communication interruption
Solution Approach 1:
The antenna system is segmented into multiple radiation paths that can be independently controlled. By distributing the radiation function across multiple paths rather than relying on a single high-power antenna, the system can achieve lower SAR exposure while maintaining communication reliability through selective path activation.
Solution Approach 2:
The system changes the operational parameters by selectively activating different radiation paths based on orientation and body proximity conditions. This parameter change allows the system to optimize between SAR reduction and communication performance by adapting which radiation path is active under different operating conditions.
3Volume of moving object
If the antenna is configured inside the electronic apparatus for compact design, then the device portability is improved, but SAR exposure increases due to body effect affecting signal transceiving
Solution Approach 1:
The internal antenna is segmented into multiple radiation paths positioned at different locations within the compact device. This segmentation allows the system to select radiation paths that are farther from the user's body when the device is held in certain orientations, thereby reducing SAR exposure while maintaining the compact form factor.
Solution Approach 2:
The system dynamically selects which internal radiation path to activate based on the device's orientation and proximity to the user's body. This dynamic selection allows the compact internal antenna configuration to adaptively minimize SAR exposure without requiring a larger external antenna structure.
Data Source
AI summary
An electronic apparatus includes a casing, at least an antenna body, a feeding point and a control unit. The casing has a display portion. The antenna body is disposed at the casing and at least has two radiation paths and a switching element. Parts of the radiation paths are respectively disposed at two sides of the display portion. The switching element is electrically connected with the radiation paths. The feeding point is electrically connected with the switching element and operationally connected to one of the radiation paths. The control unit controls the switching element based on the rotation of the electronic apparatus. When one of the radiation paths is located between a user and the display portion, the control unit controls to selectively switch the switching element for connecting the other radiation path to the feeding point.