Fractional Order Smith Chart Impedance Matching

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional impedance matching networks in RF and microwave designs are limited by the use of integer order elements, which restrict the range of impedances that can be matched and require multiple elements, whereas fractional order elements offer greater design freedom and versatility but lack effective graphical tools for design, particularly in Smith charts.

Innovation Solution

The introduction of fractional order elements, which have impedance proportional to sα, providing additional control over phase and frequency dependence, allowing a single element to match complex impedances across a wider range, including negative resistances, through the use of fractional order Smith charts and series/parallel fractional element matching networks.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If conventional integer order elements (inductor or capacitor) are used for impedance matching, then the design is simple and well-established, but the range of impedances that can be matched is limited and multiple elements are required

Engineering Contradiction:
Improverange of impedances that can be matchedVSAvoidnumber of elements required
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent applies parameter changes by transitioning from integer order elements (α=1) to fractional order elements (0<α<1). This fundamental parameter change in the order of the reactive element enables a single element to provide continuous phase shift from 0 to 90 degrees, thereby expanding the range of matchable impedances and reducing the number of elements required in the matching network.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent introduces dynamics by making the phase shift continuous and可调 through the fractional order parameter α. Unlike fixed integer order elements, fractional order elements provide dynamic control over the phase response, allowing the matching network to adapt to a broader range of load impedances with a single configurable element.

Inventive Principle:
Principle #15Dynamics

2Adaptability or versatility

If fractional order elements are used for impedance matching, then design freedom and versatility are improved, but lack of effective graphical tools for design (particularly Smith charts) is a limitation

Engineering Contradiction:
Improvedesign freedomVSAvoidavailability of graphical design tools
Core Design Contradiction:
Adaptability or versatilityVSDifficulty of detecting and measuring

Solution Approach 1:

The patent introduces an intermediary tool - the fractional order Smith chart - that bridges the gap between conventional design methods and fractional order elements. This specialized graphical tool adapts the familiar Smith chart concept to accommodate fractional order impedance relationships, enabling designers to visualize and design fractional order matching networks using graphical methods similar to conventional approaches.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent extends the conventional Smith chart into another dimension by incorporating the fractional order parameter α as an additional degree of freedom. This creates a multi-dimensional design space where designers can navigate both the traditional impedance plane and the fractional order parameter, providing intuitive graphical access to the expanded design freedom offered by fractional elements.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Data Source

PatentUS8762114B2Fractional order element based impedance matching
Publication Date: 2014.06.24 KING ABDULLAH UNIV OF SCI & TECH
  • US8762114B2 patent drawing
  • US8762114B2 patent drawing
  • US8762114B2 patent drawing

AI summary

Disclosed are various embodiments of methods and systems related to fractional order element based impedance matching. In one embodiment, a method includes aligning a traditional Smith chart (|α|=1) with a fractional order Smith chart (|α|≠1). A load impedance is located on the traditional Smith chart and projected onto the fractional order Smith chart. A fractional order matching element is determined by transitioning along a matching circle of the fractional order Smith chart based at least in part upon characteristic line impedance. In another embodiment, a system includes a fractional order impedance matching application executed in a computing device. The fractional order impedance matching application includes logic that obtains a first set of Smith chart coordinates at a first order, determines a second set of Smith chart coordinates at a second order, and determines a fractional order matching element from the second set of Smith chart coordinates.