Three-Wire Matching Circuit for Wideband Impedance Matching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing RF power amplifiers using transmission line transformers face a narrow bandwidth issue, which is exacerbated by the increase in circuit size when multiple transformers are connected to widen the band.
Innovation Solution
A matching circuit design utilizing a three-wire transformer configuration, where each wire is electromagnetically coupled to at least one other wire, allowing for impedance matching across a wide frequency band without significantly increasing the circuit size.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If multiple transmission line transformers are connected to widen the frequency band, then the bandwidth is improved, but the circuit size is increased
Solution Approach 1:
The patent combines multiple transformer windings (first, second, and third windings) into a single integrated transmission line transformer structure. This merging approach allows the circuit to achieve wide frequency band matching without requiring multiple separate transformer components, thereby widening the frequency band while suppressing the increase in circuit size.
Solution Approach 2:
The transmission line transformer is designed with multiple windings that can serve different functions simultaneously - the first winding for impedance matching, the second winding for bandwidth extension, and the third winding for additional matching flexibility. This multi-functionality allows a single component to achieve what would traditionally require multiple separate components, resolving the contradiction between bandwidth and circuit size.
2Area of stationary object
If a single transmission line transformer is used, then the circuit size is kept compact, but the frequency band is narrowed
Solution Approach 1:
The patent merges multiple windings into a single integrated transformer structure, allowing wide frequency band operation within a compact footprint. The first, second, and third windings are combined in one component rather than using multiple separate transformers, achieving both compact size and wide bandwidth.
Solution Approach 2:
The patent extends the transformer structure into the third dimension by adding multiple windings that operate at different magnetic coupling levels. This dimensional extension allows the single transformer to provide wide frequency band matching without proportionally increasing the planar circuit footprint, thus maintaining compactness while expanding frequency coverage.
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 proposed matching circuit effectively matches impedance between stages in a wide frequency range, reducing return loss and pass band loss, while maintaining a compact circuit footprint.
Implementation Method 1
a second wire having one end connected to the other end of the first wire and another end connected to a first reference potential and electromagnetically coupled to the first wire
Implementation Method 2
a third wire having one end connected to the one end of the second wire and another end connected to a second terminal and electromagnetically coupled to at least one of the first wire and the second wire
Data Source
AI summary
A matching circuit includes: a first wire having one end connected to a first terminal and another end; a second wire having one end connected to the other end of the first wire and another end connected to a first reference potential and electromagnetically coupled to the first wire; and a third wire having one end connected to the one end of the second wire and another end connected to a second terminal and electromagnetically coupled to at least one of the first wire and the second wire.