Dual Polarized Dipole Antenna Isolation via Offset Feed Orientation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing dual polarized antennas suffer from poor isolation characteristics due to coupling between dipole elements and their feed microstrips, which affects antenna performance and is not adequately improved by the use of parasitic structures.
Innovation Solution
The solution involves orienting the electric field of each dipole parallel to only its own feed microstrip, ensuring orthogonality with the other dipole's feed microstrip and electric field, and employing balanced feed systems with baluns to reduce coupling and enhance isolation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If orthogonal dipoles with coincident centers are used, then dual polarization is achieved, but coupling occurs between dipoles and feed microstrips resulting in poor isolation
Solution Approach 1:
The patent applies asymmetry by offsetting the centers of the two orthogonal dipoles from each other. Specifically, the first dipole is positioned at a first offset location and the second dipole is positioned at a second offset location, creating an asymmetric configuration that eliminates the coupling between dipoles and the other dipole's feed microstrip, thereby achieving high isolation while maintaining dual polarization capability
Solution Approach 2:
The patent utilizes spatial dimensionality by introducing offset positions in three-dimensional space. The dipoles are arranged such that their centers are offset from each other along specific axes, effectively using dimensional positioning to separate the electromagnetic fields and reduce coupling, thus improving isolation without compromising the dual polarization function
2Object-affected harmful factors
If parasitic structures are added to improve isolation, then some coupling cancellation is achieved, but radiation pattern performance deteriorates and cost increases
Solution Approach 1:
The patent extracts and eliminates the source of coupling by offsetting the dipole centers, thereby removing the need for parasitic structures. The offset configuration inherently prevents the electric field of one dipole from being parallel to the other dipole's feed microstrip, naturally achieving high isolation without adding extra parasitic elements that would degrade radiation performance or increase cost
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 configuration significantly improves isolation between dipoles and feed systems, reducing coupling and maintaining radiation pattern performance, as depicted in the graphical representations.
Implementation Method 1
orienting the electric field of a first dipole parallel to an electric field of a first feed microstrip associated with the first dipole and orthogonal to an electric field of a second feed microstrip associated with a second dipole
Data Source
AI summary
An apparatus that achieves high isolation between dipoles and feed systems is provided. The apparatus includes a plurality of transmission lines, a first dipole electrically connected to a first set of the plurality of transmission lines, and second dipole electrically connected to a second set of the plurality of transmission lines. The electric field of the first dipole is parallel to an electric field of the first set of the plurality of transmission lines, and an electric field of the second dipole is parallel to an electric field of the second set of the plurality of transmission lines.