Line-Symmetrical Antenna Element for Low-Scrap Circular Polarization

Solution Overview

Problem

Manufacturing antenna elements with four-fold rotational symmetry for circularly polarized radio wave transmission results in high material waste due to the need for punching out shapes with rotational symmetry, increasing costs.

Innovation Solution

Designing antenna elements with line symmetry and incorporating recessed portions and stubs to compensate for the lack of rotational symmetry, improving axial ratio characteristics while reducing material waste.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the antenna element is designed with four-fold rotational symmetry to transmit/receive circularly polarized radio wave, then the axial ratio characteristics are improved, but a large amount of scrap is generated from the metal plate during manufacturing

Engineering Contradiction:

Improveaxial ratio characteristicsVSAvoidscrap from metal plate

Core Design Contradiction:

ReliabilityVSLoss of substance

Solution Approach 1:

The invention changes the outer periphery shape from four-fold rotational symmetry to line symmetry, which reduces scrap generation during manufacturing. The asymmetry principle is applied by intentionally designing a non-rotational symmetric outer periphery while maintaining the necessary electromagnetic performance through strategic placement of recessed portions.

Inventive Principle:

Principle #4Asymmetry

Solution Approach 2:

The invention applies local quality by adding recessed portions at specific locations on the antenna element. These locally modified regions compensate for the lack of rotational symmetry in the overall shape, maintaining the axial ratio characteristics needed for circularly polarized radio wave transmission/reception while allowing the outer periphery to have a more manufacturable line-symmetrical form.

Inventive Principle:

Principle #3Local quality

2Loss of substance

If the developed plan of the antenna element is modified to have a shape with line symmetry to reduce material cost, then material cost is reduced, but the antenna element lacks rotational symmetry and axial ratio characteristics are degraded

Engineering Contradiction:

Improvematerial costVSAvoidaxial ratio characteristics

Core Design Contradiction:

Loss of substanceVSReliability

Solution Approach 1:

The invention applies local quality by adding recessed portions at specific locations on the antenna element. These locally modified regions compensate for the lack of rotational symmetry in the overall shape, maintaining the axial ratio characteristics needed for circularly polarized radio wave transmission/reception while allowing the outer periphery to have a more manufacturable line-symmetrical form.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The invention changes the geometric parameters of the antenna element by introducing recessed portions with specific dimensions and positions. These parameter changes locally adjust the electromagnetic field distribution to compensate for the overall line-symmetrical shape, thereby maintaining the necessary axial ratio characteristics.

Inventive Principle:

Principle #35Parameter changes

3Reliability

If the antenna element requires rotational symmetry to transmit/receive circularly polarized radio wave, then the axial ratio characteristics are improved, but the design flexibility is reduced

Engineering Contradiction:

Improveaxial ratio characteristicsVSAvoiddesign flexibility

Core Design Contradiction:

ReliabilityVSAdaptability or versatility

Solution Approach 1:

The invention changes the outer periphery shape from four-fold rotational symmetry to line symmetry, which reduces scrap generation during manufacturing. The asymmetry principle is applied by intentionally designing a non-rotational symmetric outer periphery while maintaining the necessary electromagnetic performance through strategic placement of recessed portions.

Inventive Principle:

Principle #4Asymmetry

Solution Approach 2:

The invention applies local quality by adding recessed portions at specific locations on the antenna element. These locally modified regions compensate for the lack of rotational symmetry in the overall shape, maintaining the axial ratio characteristics needed for circularly polarized radio wave transmission/reception while allowing the outer periphery to have a more manufacturable line-symmetrical form.

Inventive Principle:

Principle #3Local quality

Data Source

PatentUS12609443B2Antenna element and antenna device

Publication Date: 2026.04.21 JAPAN AVIATION ELECTRONICS IND LTD

AI summary

An antenna element comprises an upper conductor and at least one pair of legs. When the upper conductor is viewed along an up-down direction, one of the legs of the pair protrudes in a first orientation while a remaining one of the legs of the pair protrudes in a second orientation. The upper conductor is provided with at least one pair of recessed portions. When the upper conductor is viewed along the up-down direction, one of the recessed portions of the pair is recessed in the second orientation while a remaining one of the recessed portions of the pair is recessed in the first orientation. Each of the recessed portions is juxtaposed with the corresponding leg in a direction intersecting with a first direction which is defined by the first orientation and the second orientation.