Switchable Phase Shifter on Flexible Coplanar Strip Line

Solution Overview

Problem

Conventional phase array antennas require additional circuitry and balun transitions for interfacing with balanced microwave transmission lines, leading to increased size, weight, and cost due to the need for balun transitions on both input and output sides of conventional phase shifters.

Innovation Solution

A wideband microwave switchable 0 or 180 degrees phase shifter is implemented using a thin flexible coplanar strip (CPS) transmission line, which directly interfaces with the antenna radiator without the need for balun transitions, allowing for lightweight and flexible phased array lens antennas.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If conventional unbalanced phase shifters with balun transitions are used to interface with balanced transmission lines, then phase shifting functionality is achieved, but size, weight and cost increase due to additional balun circuitry on both input and output sides

Engineering Contradiction:

Improvecircuitry complexityVSAvoidantenna weight

Core Design Contradiction:

Device complexityVSWeight of moving object

Solution Approach 1:

The patent merges the phase shifter and balun functions into a single integrated structure. The coplanar strip transmission line directly interfaces with the balanced dipole antenna feed, eliminating the need for separate balun transitions on both input and output sides of the phase shifter. This integration reduces the number of discrete components and interconnections required.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The coplanar strip transmission line serves multiple functions simultaneously: it provides balanced-to-unbalanced transformation (acting as a balun) and serves as the transmission medium for the phase shifter. This multi-functionality eliminates the need for dedicated balun components, reducing overall device complexity and weight.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Device complexity

If conventional unbalanced phase shifters with balun transitions are used, then phase shifting is enabled, but the overall size and cost per antenna element increase

Engineering Contradiction:

Improvecircuitry complexityVSAvoidantenna size

Core Design Contradiction:

Device complexityVSArea of stationary object

Solution Approach 1:

The patent merges the phase shifter and balun functions into a single integrated structure. The coplanar strip transmission line directly interfaces with the balanced dipole antenna feed, eliminating the need for separate balun transitions on both input and output sides of the phase shifter. This integration reduces the number of discrete components and interconnections required.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent employs thin flexible substrates to support the coplanar strip transmission line and phase shifter circuitry. This allows the antenna elements to be made compact and lightweight while maintaining electrical performance, reducing the overall area required for each antenna element.

Inventive Principle:

Principle #30Flexible shells and thin films

3Reliability

If conventional unbalanced transmission lines are used, then microwave signal transmission is achieved, but weight increases and flexibility is reduced for space deployment and stowage

Engineering Contradiction:

Improvesignal transmission reliabilityVSAvoidtransmission line weight

Core Design Contradiction:

ReliabilityVSWeight of moving object

Solution Approach 1:

The patent employs thin flexible substrates to support the coplanar strip transmission line and phase shifter circuitry. This allows the antenna elements to be made compact and lightweight while maintaining electrical performance, reducing the overall area required for each antenna element.

Inventive Principle:

Principle #30Flexible shells and thin films

Solution Approach 2:

The patent transitions from conventional unbalanced transmission lines to coplanar strip transmission lines, changing the transmission line geometry and balancing characteristics. This parameter change enables the use of thinner, lighter flexible substrates while maintaining signal transmission reliability through the balanced configuration.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentEP2230713B1Switchable 0 degree/180 degree phase shifter on flexible coplanar strip transmission line

Publication Date: 2012.01.18 RAYTHEON CO

Figure 1
Figure 2a~2c
Figure 2d~2e

AI summary

A switchable 0°/180° phase shifter on a balanced transmission line is provided. In one embodiment, the invention relates to an apparatus for providing 0°/180° phase shifting for a transmit/receive antenna pair including a transmit element and a receive element coupled by a balanced transmission line having two sections, the apparatus including a first section of the balanced transmission line, the first section including a first conductor and a second conductor, a second section of the balanced transmission line, the second section including a third conductor and a fourth conductor, and a switch disposed between the first section and the second section, wherein in a first configuration, the switch couples the first conductor to the third conductor and the second conductor to the fourth conductor, and in a second configuration, the switch couples the first conductor to the fourth conductor and the second conductor to the third conductor.