Antenna Sensitivity in Portable Terminals via Touch Pad Grounding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The receiving sensitivity of LTE antennas in portable terminals is compromised due to low-frequency noise leakage from touch Integrated Circuits, particularly in the 5 Band (869 MHz through 894 MHz), which affects the antenna's ability to receive RF signals effectively.
Innovation Solution
A conductive portion is introduced between the touch pad unit and the display bracket to ground the touch pad unit, blocking noise and improving antenna receiving sensitivity by connecting it to the display bracket, which is made of a magnesium alloy, and modifying the touch pad unit to a 3-layer structure with a ground layer to absorb and redirect noise away from the antenna.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If the touch pad unit is disposed close to the antenna to save space, then the device compactness is improved, but the receiving sensitivity of the antenna deteriorates due to noise leakage from the touch IC
Solution Approach 1:
A conductive portion is introduced as an intermediary element between the touch pad unit and the display bracket. This conductive portion serves as a noise shielding barrier that blocks electromagnetic noise from the touch IC from reaching the antenna, while still allowing the touch pad unit to be disposed close to the antenna for compact device design.
Solution Approach 2:
The touch pad unit is divided into separate functional layers including a touch pad layer, signal line layer, and ground layer. This segmentation allows the ground layer to be specifically optimized for noise shielding purposes while maintaining the overall compact structure near the antenna.
2Ease of operation
If the touch pad unit operates continuously to sense user input, then the ease of operation is improved, but noise is generated and leaked to the antenna, worsening the receiving sensitivity
Solution Approach 1:
The conductive portion acts as a continuous noise barrier between the operating touch pad unit and the antenna. This intermediary structure blocks noise generated during continuous touch pad operation from reaching the antenna, allowing the touch pad to remain fully operational without compromising antenna performance.
Solution Approach 2:
The conductive portion is strategically positioned only in the specific region between the touch pad unit and the antenna where noise leakage occurs. This localized noise shielding approach maintains the full operational capability of the touch pad while selectively blocking noise in the critical path to the antenna.
3Reliability
If a conductive portion is added to ground the touch pad unit for noise blocking, then the receiving sensitivity is improved, but the device complexity increases
Solution Approach 1:
The conductive portion is merged with the existing display bracket structure, combining the noise shielding function with the structural support function of the display bracket. This integration approach improves receiving sensitivity while minimizing the increase in overall device complexity by utilizing existing structural elements.
Solution Approach 2:
The conductive portion is designed to serve multiple functions: it acts as a noise shielding barrier, provides electrical grounding for the touch pad unit, and integrates with the display bracket structure. This multi-functionality reduces the need for separate components, thereby limiting the increase in device complexity while achieving improved receiving sensitivity.
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 solution enhances the LTE antenna's receiving sensitivity by approximately 10% compared to conventional designs, effectively blocking noise and improving signal reception in the low-frequency band.
Implementation Method 1
a conductive portion disposed between the display bracket and the touch pad unit to connect noise introduced from the touch pad unit toward the display bracket which in turn blocks the noise introduction to the antenna
Implementation Method 2
modifying the touch pad unit to a 3-layer structure with a ground layer to absorb and redirect noise away from the antenna
Data Source
AI summary
A device for improving antenna receiving sensitivity in a portable terminal includes an antenna in a low-frequency band of less than 900 MHz which is mounted on a predetermined position in a body housing and a touch pad unit connected to the vicinity of the antenna through a FPCB (Flexible Printed Circuit Board), in which the touch pad unit is grounded to a nearby body in the vicinity of the touch pad unit by using a conductive portion to block noise generated in the touch pad unit, thereby improving the antenna receiving sensitivity.