Multi-frequency Antenna with Dual Loops for Broad Bandwidth
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional multi-frequency antennas face challenges in achieving broad bandwidth and compact design, particularly in high-frequency bands, and are difficult to fabricate due to close connection portions and complex structures.
Innovation Solution
A multi-frequency antenna with dual loops is designed using a T-shaped radiator and two grounded L-shaped radiators, which form independent loops to broaden bandwidth and simplify fabrication by employing capacitive coupling for frequency adjustment and impedance matching.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If conventional planar inverted-F antenna (PIFA) is used, then the antenna structure is simple, but the bandwidth is insufficient for multi-frequency operation
Solution Approach 1:
The antenna is divided into multiple radiating elements (first radiating element, second radiating element, third radiating element) with different lengths and configurations. Each element contributes to different frequency bands, enabling multi-frequency operation while maintaining a relatively simple overall structure.
Solution Approach 2:
The antenna design integrates multiple radiating elements that can simultaneously support multiple frequency bands (GSM900, DCS1800, PCS1900, UMTS2100). The shared ground structure and feed network allow a single antenna system to perform multiple functions across different frequency ranges.
2Adaptability or versatility
If multiple top plates are used to broaden bandwidth, then the multi-frequency effect is improved, but the structure becomes too complex for compact devices
Solution Approach 1:
Instead of using multiple top plates, the invention segments the radiating structure into multiple elements (first, second, and third radiating elements) with different lengths and orientations. This segmentation achieves multi-frequency capability while maintaining a compact and manageable structure suitable for mobile devices.
Solution Approach 2:
The antenna elements are arranged in different spatial dimensions and orientations (different lengths, angles, and positions relative to the ground). This dimensional arrangement enables multi-frequency operation without requiring multiple stacked top plates, thus reducing structural complexity.
3Volume of moving object
If connection portions are placed close together to save space, then the antenna size is reduced, but the high-frequency bandwidth requirement is not met
Solution Approach 1:
Different portions of the antenna structure have different characteristics: the first radiating element has a specific length for low-frequency operation, while the second and third elements have different configurations optimized for high-frequency bands. This local differentiation allows the antenna to meet bandwidth requirements in specific frequency ranges while maintaining overall compactness.
Solution Approach 2:
The antenna design incorporates adjustable parameters (element lengths, spacing, and configurations) that can be optimized for different frequency bands. The dynamic adjustment of these parameters allows the antenna to maintain performance across multiple frequencies while adapting to space constraints.
4Ease of manufacture
If first and second radiating portions extend from the same direction to simplify layout, then the fabrication is difficult when bending and welding
Solution Approach 1:
The radiating elements are designed with asymmetric configurations - the first radiating element has a different length and orientation compared to the second and third elements. This asymmetric design simplifies the layout and fabrication process by avoiding the need to bend and weld identical components from the same direction, while still achieving the desired multi-frequency performance.
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 achieves a broad bandwidth of 1710-2170 MHz for high-frequency bands and 824-960 MHz for low-frequency bands, meeting requirements for systems like DCS, PCS, UMTS, AMPS, and GSM, while reducing fabrication complexity and cost.
Implementation Method 1
A multi-frequency antenna with dual loops is designed using a T-shaped radiator and two grounded L-shaped radiators, which form independent loops to broaden bandwidth and simplify fabrication by employing capacitive coupling for frequency adjustment and impedance matching.
Data Source
AI summary
A multi-frequency antenna with dual loops is provided. The antenna includes a T-shaped radiator having a first arm and a second arm of unequal lengths as a main body, and two grounded L-shaped radiators, so as to form dual loops. Thus, the antenna can operate in a high-frequency operation mode and a low-frequency operation mode. With the dual loops, the antenna obtains enough bandwidths at high frequency, and also meets the requirements of low frequency. More specific, the antenna meets the requirements of high-frequency systems, such as DCS/PCS/UMTS and those of low-frequency systems, such as AMPS/GSM.