3D Recessed Absorber for Broadband Antenna Decoupling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing antenna systems face challenges with electromagnetic coupling between antenna assemblies, leading to undesirable effects such as standing wave ratio increases, radiation pattern degradation, and desensitization of reception chains, which are not effectively addressed by current decoupling methods like corrugated metal planes or bulk electromagnetic absorbers due to limited frequency bandwidth, mechanical constraints, and reproducibility issues.
Innovation Solution
A 3D structured electromagnetic absorber with a recessed pattern is used to decouple antenna assemblies, comprising a base and raised walls forming an array that absorbs electromagnetic waves effectively at various angles of incidence, allowing for broad frequency band operation and compact design.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a corrugated metal plane is used to trap electromagnetic waves, then decoupling effectiveness is improved at a given frequency, but the operating frequency band is reduced to a narrow range around the resonant frequency
Solution Approach 1:
The patent transitions from a 2D corrugated surface to a 3D structured absorber with vertical elements extending from the metal plane. This third dimension (height of absorber structures) enables broadband operation by creating multiple resonance modes and improving impedance matching across a wider frequency range, thereby resolving the contradiction between decoupling effectiveness and frequency band adaptability
2Reliability
If the metal plane is corrugated with depth about λ/4, then electromagnetic waves are trapped effectively, but the thickness of the metal plane must be greater than the depth of the corrugations
Solution Approach 1:
The patent segments the absorber structure into modular units with standardized dimensions. The metal plane thickness is decoupled from the absorber height, allowing the absorber to be mounted on thinner planes. This segmentation enables the trapping effectiveness to be achieved without increasing the base metal plane thickness, resolving the contradiction between wave trapping and plane thickness
3Reliability
If more corrugations are added to improve decoupling, then decoupling performance is enhanced, but the spacing between antenna assemblies must be sufficient to position enough corrugations
Solution Approach 1:
The patent changes the key parameter from corrugation count to absorber height and material properties. By adjusting the height of the 3D absorber structures and their electromagnetic properties, effective decoupling is achieved with fewer elements, reducing the required spacing between antenna assemblies while maintaining or improving decoupling performance
4Strength
If dielectric foam or radome material is used to fill corrugations for mechanical strength, then mechanical strength is improved, but additional machining constraints and production costs arise
Solution Approach 1:
The patent uses composite materials consisting of a metal plane base combined with 3D printed or molded absorber structures made from dielectric or magneto-dielectric materials. This composite approach provides the necessary mechanical strength while allowing for simplified manufacturing processes compared to traditional corrugated structures filled with foam, reducing both machining constraints and production costs
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 3D structured absorber significantly reduces coupling between antenna assemblies, stabilizes gain patterns, and maintains high absorptivity over a wide frequency range, improving antenna performance and compactness while minimizing mass and production complexity.
Implementation Method 1
a 3D structured electromagnetic absorber with a recessed pattern that absorbs, whatever may be the angle of incidence of the electromagnetic wave
Implementation Method 2
The unit cell comprises a base and a raised wall formed integrally of the same piece of material or of two pieces of material joined together... made of a dielectric material or of a magneto-dielectric material
Implementation Method 3
made of a dielectric material or of a magneto-dielectric material... the raised wall has a height that is greater than the diagonal of the base
Data Source
AI summary
An antenna system including at least one elementary antenna, a metallic plane provided around the elementary antenna, and a decoupling device arranged on the metallic plane, the decoupling device being of the three-dimensional electromagnetic absorption structure type constituted of a plurality of cells arranged in an array, each cell includes, stacked according to a direction normal to the metal plane, a base surmounted by a raised wall, the antenna system being characterized in that the raised wall is shaped so as to form a recessed pattern for trapping electromagnetic waves.