Wave-Transparent Matching Structure for Antenna Reflection Suppression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Antennas such as microstrip antennas strongly radiate electromagnetic waves in the forward direction, and when a main substrate with relatively high relative permittivity is positioned forward, electromagnetic waves are reflected at the interface of the substrate.
Innovation Solution
An electromagnetic wave transparent body comprising a main substrate with specific permittivity and dielectric loss tangent, an intermediate layer with specific permittivity and loss tangent, and a matching layer with adjusted permittivity and loss tangent, satisfying specific thickness and impedance matching conditions to suppress electromagnetic wave reflection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If a main substrate with relatively high relative permittivity is positioned forward of an antenna, then electromagnetic wave radiation in the forward direction is enhanced, but electromagnetic wave reflection occurs at the substrate interface
Solution Approach 1:
An intermediate layer with relative permittivity of 1 to 1.5 is introduced between the main substrate (εr1=4 to 7) and the matching layer (εr3=0.7√εr1 to 1.3√εr1). This intermediate layer acts as a mediator that gradually transitions the electromagnetic impedance, reducing the abrupt impedance mismatch at the substrate interface and thereby suppressing reflection while maintaining forward radiation enhancement.
Solution Approach 2:
The patent employs a gradient structure where the relative permittivity changes progressively from the main substrate (εr1=4 to 7) through the intermediate layer (εr2=1 to 1.5) to the matching layer (εr3=0.7√εr1 to 1.3√εr1). This parameter gradient allows smooth impedance transformation, reducing reflection coefficients at each interface while maintaining the overall forward radiation capability.
2Reliability
If an electromagnetic wave transparent body with multiple layers is used to suppress reflection, then electromagnetic wave transmission performance is improved, but the device structure becomes more complex
Solution Approach 1:
Each layer in the electromagnetic wave transparent body is assigned a specific local property (relative permittivity and thickness) optimized for its position: the main substrate (εr1=4 to 7, thickness d1) provides structural support and initial impedance control, the intermediate layer (εr2=1 to 1.5, thickness d2) provides impedance transition, and the matching layer (εr3=0.7√εr1 to 1.3√εr1, thickness d3) provides final impedance matching. This localized optimization achieves high transmission reliability with a relatively simple three-layer structure.
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 solution effectively reduces electromagnetic wave reflection, allowing for efficient transmission through the substrate while maintaining low transmission loss and impedance matching.
Implementation Method 1
when a main substrate (such as a window glass or glass facade etc.) having a relatively high relative permittivity is situated frontward (forward) of an antenna, electromagnetic waves are reflected at the interface of the main substrate
Implementation Method 2
a matching layer located on the first side with respect to the intermediate layer and having, at the frequency f, a relative permittivity εr3 of from 0.7 times to 1.3 times a value of √(εr1)
Implementation Method 3
a main substrate having, at a frequency f of electromagnetic wave, a relative permittivity εr1 of from 4 to 7 and a dielectric loss tangent of 1.4/f or less
Data Source
AI summary
Provided is an electromagnetic wave transparent body, in which reflection of electromagnetic waves can be suppressed. An electromagnetic wave transparent body according to one embodiment satisfies the following formulas:(n1−0.3)×(C0/(4×f×√(εr1)))≤d1≤(n1+0.3)×(C0/(4×f×√(εr1))); d2=n2×C0/(4×f×√(εr2)); d3=n3×C0/(4×f×√(εr3)); 0≤n2≤2; 0<n3≤3;(((n3−)cosθ+(n2−a2)sinθ)/a3)2+((−(n3−1)sinθ+(n2−a2)cosθ)/a4)2≥1;(((n3−3)cosθ+(n2−a2)sinθ)/a3)2+((−(n3−3)sinθ+(n2−a2)cosθ)/a4)2≥1; θ=−38°; a2=1; a3=1.2; and a4=0.6, where d1 is a total thickness of a main substrate; d2 is a thickness of an intermediate layer; d3 is a thickness of a matching layer; C0 is a speed of electromagnetic wave in air; f is a frequency of electromagnetic wave; and n1 is an even number from 2 to 20.