Fabry-Perot Etalon Window for 5G Signal Transmission

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Solution Overview

Problem

Modern windows with low-E coatings, designed for energy efficiency, attenuate 5G cellular frequencies, making it difficult to maintain indoor connectivity without external antennas and coaxial cables, which pose challenges in routing and powering these units.

Innovation Solution

Incorporating a Fabry-Perot etalon in window structures, using a transparent glass layer with low-E coatings on both sides of a middle glass layer, creating a bandpass filter that allows 5G frequencies to pass through while maintaining infrared reflectivity, enabling microwave transparency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If low-E coatings are applied to window surfaces for energy efficiency, then infrared radiation is blocked and thermal performance is improved, but 5G microwave frequencies are attenuated by up to 40dB

Engineering Contradiction:
Improvethermal energy lossVSAvoid5G signal transmission
Core Design Contradiction:
Loss of energyVSReliability

Solution Approach 1:

The window is divided into multiple glass layers with low-E coatings applied selectively to specific surfaces. The third glass layer positioned between the first and second glass layers has low-E coatings on both opposing surfaces, creating a Fabry-Perot etalon structure that segments the window assembly to achieve both thermal and microwave performance

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The optical properties of the low-E coatings are specifically engineered to reflect infrared frequencies while transmitting microwave frequencies. By controlling the coating composition, thickness, and positioning on the glass layers, the window achieves selective frequency transmission - blocking thermal infrared radiation while allowing 5G microwave signals to pass through

Inventive Principle:
Principle #35Parameter changes

2Reliability

If external antennas are placed outside the structure to maintain 5G connectivity, then signal reception is improved, but cable routing complexity and installation difficulty increase

Engineering Contradiction:
Improve5G signal receptionVSAvoidcable routing and installation
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The antenna function is extracted from the external environment and integrated directly into the window structure itself. The Fabry-Perot etalon formed by the third glass layer with low-E coatings on both surfaces acts as an inherent microwave transmission element, eliminating the need for separate external antennas and their associated cable routing infrastructure

Inventive Principle:
Principle #2Taking out (Extraction)

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 allows for effective transmission of 5G frequencies through windows, reducing the need for external antennas and coaxial cables, enhancing indoor connectivity with reduced signal loss and complexity in cable routing and powering.

Implementation Method 1

first and second low-E coatings on respective first and second opposing surfaces of the third glass layer to form a Fabry-Perot etalon that is configured as a bandpass filter having a designated frequency passband that includes at least one frequency in a range of frequencies from 6 gigahertz to 80 gigahertz

Methodology Applied
Scientific EffectFabry-Perot etalon: Fabry-Perot Interferometer

Implementation Method 2

form a Fabry-Perot etalon that is configured as a bandpass filter having a designated frequency passband

Methodology Applied
Scientific EffectBandpass filter: Filter (electronic)

Implementation Method 3

Each low-E coating manages electromagnetic (EM) radiation that is incident on the coating... low thermal emissivity coatings on respective first and second opposing surfaces of the third glass layer

Methodology Applied
Scientific EffectLow thermal emissivity coating: Reflection

Data Source

PatentEP3774685B1Energy-efficient, microwave-transparent window compatible with present design
Publication Date: 2023.09.06 CORNING INC
  • EP3774685B1 patent drawingFigure 1~2
  • EP3774685B1 patent drawingFigure 3~4
  • EP3774685B1 patent drawingFigure 5~6

AI summary

A window structure includes first, second, and third glass layers. The third glass layer is positioned between the first and second glass layers. First and second low thermal emissivity coatings are on respective first and second opposing surfaces of the third glass layer to form a Fabry-Perot etalon that is configured as a bandpass filter having a designated frequency passband that includes at least one frequency in a range of frequencies from (6) gigahertz to (80) gigahertz.