Wall-Mounted EM Wave Absorber Using Resistive Dipoles
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current solutions for absorbing electromagnetic waves, particularly in the VHF and UHF ranges, are ineffective for outdoor use and do not adequately address stray reflections from building structures, which interfere with radio measurement systems near airports, due to the use of thick absorbent foams and reflective diffraction devices.
Innovation Solution
A device comprising a metal plate, a dielectric panel, and an array of resistive dipoles with a resistor between metal platelets, fixed on a wall, which creates a volume for effective absorption of electromagnetic waves, including metal walls for enhanced capacitive coupling and a protective dielectric plate for weather resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If thick absorbent foams are used to absorb electromagnetic waves, then absorption effectiveness is improved, but the device becomes unsuitable for outdoor use and installation becomes difficult
Solution Approach 1:
The foam absorber is divided into multiple thin plates (first foam plate, second foam plate, third foam plate) arranged in sequence, replacing a single thick foam structure. This segmentation maintains the total absorption path length while creating a thinner, more manageable overall structure that is easier to install and suitable for outdoor applications.
Solution Approach 2:
The invention combines multiple different materials (foam plates with specific dielectric constants, metallic mesh screens, and air gaps) to create a composite absorption structure. Each material contributes different properties: foam plates provide dielectric loss, metallic screens provide conductive loss and shielding, and air gaps provide impedance matching. This composite approach achieves effective absorption with a thinner overall structure.
2Loss of energy
If diffraction screens are installed to reflect electromagnetic waves, then wave absorption is improved, but the device complexity increases and installation becomes more difficult
Solution Approach 1:
The invention merges multiple functions into a single integrated structure: the foam plates serve both as structural support and as dielectric absorption elements, while the metallic mesh screens provide both shielding and structural reinforcement. This combination eliminates the need for separate diffraction screens and simplifies the overall device structure while maintaining effective electromagnetic wave reflection and absorption.
Solution Approach 2:
The invention changes the approach from geometric diffraction (complex screen patterns) to material property-based absorption (controlling dielectric constants and conductivity of foam and metallic layers). By adjusting material parameters rather than geometric parameters, the device achieves effective wave reflection with a simpler structure.
3Loss of energy
If a single thick foam plate is used, then absorption effectiveness is improved, but the device weight increases and installation becomes more difficult
Solution Approach 1:
The single thick foam plate is segmented into multiple thinner foam plates separated by air gaps or metallic mesh screens. This segmentation reduces the weight of each individual component while maintaining the total absorption path length, making the overall device lighter and easier to handle during installation.
Solution Approach 2:
Air gaps or thin metallic mesh screens are introduced as intermediary elements between the foam plates. These intermediaries have negligible weight compared to solid foam material but provide important functions: impedance matching, structural support, and additional absorption mechanisms, thereby reducing overall device weight while maintaining absorption effectiveness.
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 device achieves significant absorption of electromagnetic waves, particularly in the UHF and VHF bands, reducing signal reflections and interference, while being lightweight, easy to install, and suitable for outdoor use.
Implementation Method 1
an array of resistive dipoles, all the resistive dipoles being fixed on the same face of the dielectric panel, and each comprising two metal platelets at a distance from one another and a resistor arranged between the opposing edges of two neighboring metal platelets
Implementation Method 2
a dielectric panel at a distance from the metal plate and delimiting, with the metal plate, a volume between the metal plate and the dielectric panel
Data Source
AI summary
A device, intended to be fixed on a wall, for absorbing electromagnetic waves. The absorption device comprises a metal plate intended to be fixed on the wall, a dielectric panel at a distance from the metal plate and delimiting, with the metal plate, a volume between the metal plate and the dielectric panel, an array of resistive dipoles, all the resistive dipoles being fixed on the same face of the dielectric panel, and each comprising two metal platelets at a distance from one another and a resistor arranged between the opposing edges of two neighboring metal platelets.