Multiband Slot Antenna Capacitive Coupling for Size Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing multiband antennas are not effectively downsized while maintaining resonant frequencies, as the addition of radiation elements can increase size rather than reduce it.
Innovation Solution
Incorporating an additional element that adjusts the impedance of the multiband antenna, specifically forming a capacitor between the additional element and the slot edge portion, allowing for a lower resonant frequency and downsizing of the antenna.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a radiation element is added to lower the resonant frequency of the slot antenna, then the resonant frequency is reduced, but the antenna size increases
Solution Approach 1:
The patent changes the electrical parameters of the antenna system by introducing an additional element that forms a capacitor with the slot edge portion. This modifies the impedance and resonant frequency characteristics without requiring physical extension of the radiation elements, thereby lowering the resonant frequency while maintaining compact dimensions.
Solution Approach 2:
The additional element acts as an intermediary component that couples with the slot antenna through capacitive coupling. This intermediary structure adjusts the electrical characteristics of the antenna system, enabling frequency control without directly increasing the physical size of the main antenna structure.
2Volume of moving object
If the antenna size is reduced, then the device becomes more compact, but the resonant frequency control becomes difficult
Solution Approach 1:
By introducing the additional element with specific electrical characteristics (capacitive coupling), the patent enables independent control of resonant frequency parameters without being constrained by physical size. The electrical parameters can be adjusted through the coupling characteristics between the additional element and slot edge portion, decoupling frequency control from size scaling.
3Volume of moving object
If the slot antenna size is reduced, then the overall antenna is downsized, but the impedance matching deteriorates
Solution Approach 1:
The additional element serves as an impedance-matching intermediary between the feeding portion and the slot antenna. Through capacitive coupling, it transforms the impedance characteristics, enabling effective impedance matching in the downsized configuration where direct feeding would otherwise result in poor matching due to the reduced electrical length of the slot antenna.
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
The additional element allows for a reduction in antenna size while maintaining or improving operating frequencies, effectively downsizing the multiband antenna by adjusting its impedance and capacitance.
Implementation Method 1
forming a capacitor between the additional element and the slot edge portion
Implementation Method 2
the additional element adjusts an impedance of the multiband antenna
Implementation Method 3
the multiband antenna has two resonant frequencies or operating frequencies
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
First and second slot edge portions of a conductive main portion are long in a first direction and sandwich a slot in a second direction. An open portion is formed a part different from the first slot edge portion and opens the slot outside the conductive main portion. A first part of a radiation element extends from an end portion of the first slot edge portion in the second direction. A second part of the radiation element extends from an end portion of the first part in the first direction. An additional element extends from the second part toward a second specific area through a first specific area. In a third direction, the first specific area and the second specific area overlap with the first slot edge portion and the second slot edge portion, respectively.