Multiband Antenna with Parasitic Elements for Space-Constrained Devices
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional multiband built-in antennas face challenges in supporting a large number of communication bands due to limited arrangement space, making it difficult to increase the number of bands for devices like tablets and smartphones.
Innovation Solution
The antenna device incorporates a ground plane, radiation elements, and parasitic elements with specific geometric configurations and wavelength alignments to enable communication across multiple frequency bands without increasing physical size, including a ground element with a slit, radiation elements, and parasitic elements that collaborate to achieve resonance across five communication bands.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If conventional multiband built-in antennas are used with traditional power feeding units and radiating patches, then the antenna structure is simple, but the number of supported communication bands is limited due to restricted arrangement space
Solution Approach 1:
The antenna is divided into multiple independent functional elements: a ground element with slit, multiple radiation elements (first and second), multiple parasitic elements (first and second), and a power feeding unit. Each element is designed with specific dimensions corresponding to different wavelength fractions (λ/4, λ/2) to resonate at different frequency bands, enabling multiband operation without increasing overall footprint
Solution Approach 2:
The antenna structure utilizes three-dimensional spatial arrangement by extending elements in multiple directions (along the end side of ground plane, upward perpendicular to ground element, and in various orientations). This vertical and multi-directional configuration allows more elements to be packed into limited planar space, supporting more frequency bands within the same device footprint
2Adaptability or versatility
If multiple radiation and parasitic elements are added to support more communication bands, then the number of supported bands increases, but the device complexity increases
Solution Approach 1:
Multiple functional elements are integrated into a unified antenna structure sharing common components. The ground element serves as both the ground reference and part of the resonant structure for multiple elements. Parasitic elements are positioned to couple with radiation elements, creating interconnected resonant systems that achieve multiband operation through coordinated interaction rather than independent elements
Solution Approach 2:
The ground element with slit configuration serves multiple functions: providing ground reference for all elements, acting as part of the resonant path for different frequency bands, and enabling impedance matching across bands. The slit in the ground element specifically contributes to resonance at lower frequencies while the overall structure supports higher frequency operation, making this single component multi-functional
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 antenna device effectively supports communication in five bands from approximately 0.7 GHz to 2.7 GHz, improving the S11 parameter values and enabling multiband communication without physical expansion, as demonstrated by electromagnetic simulations and frequency characteristics.
Implementation Method 1
a radiating patch separated by a predetermined gap from the power feeding unit via a space, coupled to a portion of the power feeding unit, and configured to induce a current supplied from the power feeding unit
Implementation Method 2
the length from the feed point through the first radiation element, the grounded end, the second end, and the end side to the open end of the slit is equal to a half of a wavelength corresponding to a first communication frequency
Data Source
AI summary
An antenna device includes a ground plane configured to have an end side; a ground element configured to have a first end and a second end; a first radiation element configured to have a first line extending upright with respect to the ground element from a grounded end, a second line coupled to the first line, and a feed point; a second radiation element configured to have a third line, and a fourth line coupled to the third line; a first parasitic element configured to have a first parasitic line, and a second parasitic line coupled to the first parasitic line and extending along the ground element toward the first end; and a second parasitic element configured to have a fifth line located close to a tip of the second parasitic line, and a sixth line extending along the ground element from a tip of the fifth line.