Aircraft Radome with X and W Band Transparency Insert

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Aircraft radomes face challenges in minimizing transmission and reflection losses across various frequency bands while maintaining structural integrity and aerodynamic efficiency, particularly in bearing aerodynamic loads and resisting physical damage.

Innovation Solution

A radome design featuring a curved body transparent to X-band microwave energy (8.0 GHz to 12.6 GHz) and an insert transparent to W-band microwave energy (75 GHz to 100 GHz), with a multi-layer structure including solid laminate and foam layers, and optionally featuring elongated reinforcing members and a serrated configuration to reduce incidence angles and enhance transmission efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If a single-material radome construction is used, then manufacturing is simpler, but it cannot achieve low transmission losses across both X-band and W-band frequencies simultaneously

Engineering Contradiction:
Improveradome construction simplicityVSAvoidbroadband transmission performance
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The radome employs a composite construction with an inner PTFE layer for microwave transparency (X-band) and an outer fiberglass layer for structural strength and W-band transparency. This multi-material approach allows each layer to optimize for its specific frequency range while collectively achieving broadband performance across both X-band and W-band frequencies.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The radome is divided into distinct functional layers: an inner PTFE coating layer specifically designed for microwave transparency in the X-band, and an outer fiberglass structural layer that provides mechanical strength while maintaining transparency in the W-band. This segmentation allows each layer to be optimized for its specific purpose.

Inventive Principle:
Principle #1Segmentation

2Strength

If the radome wall is made thicker to bear aerodynamic loads, then structural strength improves, but transmission losses increase

Engineering Contradiction:
Improveaerodynamic load bearing capacityVSAvoidmicrowave transmission loss
Core Design Contradiction:
StrengthVSLoss of energy

Solution Approach 1:

The composite structure allows the outer fiberglass layer to bear aerodynamic loads while the inner PTFE layer maintains microwave transparency. The fiberglass material provides the necessary mechanical strength for thick-wall construction without proportionally increasing transmission losses, as the PTFE inner layer compensates for the attenuating effect of the thicker outer shell.

Inventive Principle:
Principle #40Composite materials

3Object-generated harmful factors

If the radome surface is made smooth for aerodynamic efficiency, then drag reduction improves, but resistance to physical damage such as bird strikes decreases

Engineering Contradiction:
Improveaerodynamic dragVSAvoidphysical damage resistance
Core Design Contradiction:
Object-generated harmful factorsVSObject-affected harmful factors

Solution Approach 1:

The outer fiberglass layer provides a tough, damage-resistant surface that can withstand bird strikes and hail impacts, while the smooth finish of this outer layer maintains aerodynamic efficiency. The composite construction allows the outer shell to serve as both the aerodynamic surface and the protective barrier against physical damage.

Inventive Principle:
Principle #40Composite materials

4Ease of manufacture

If a conventional single-layer radome is used, then manufacturing is simpler, but localized signal attenuation cannot be reduced

Engineering Contradiction:
Improveradome construction simplicityVSAvoidlocalized signal attenuation
Core Design Contradiction:
Ease of manufactureVSLoss of energy

Solution Approach 1:

The PTFE inner layer can be applied selectively in specific regions where microwave transparency is critical, such as areas directly in the path of radar beams. This localized application of the transparent material optimizes signal transmission in key areas without requiring the entire radome to use the more complex multi-layer construction.

Inventive Principle:
Principle #3Local quality

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 design achieves low transmission and reflection losses (<0.25 dB at X-band and <0.75 dB at W-band) over a 20 GHz bandwidth, providing a strong structure suitable for high-speed aircraft with improved aerodynamic performance.

Implementation Method 1

the body is transparent to microwave energy in a frequency range from about 8.0 GHz to about 12.6 GHz; and the insert is transparent to microwave energy in a frequency range from about 75 GHz to about 100 GHz

Methodology Applied
Scientific EffectElectromagnetic wave transmission: Electromagnetic Induction

Data Source

PatentEP3619041B1Aircraft radomes with broadband transparency
Publication Date: 2022.01.05 VU SYSTEMS LLC
  • EP3619041B1 patent drawingFigure 1~2
  • EP3619041B1 patent drawingFigure 3A~3B
  • EP3619041B1 patent drawingFigure 3C~4

AI summary

An aircraft nose radome has a first portion that is transparent to X band microwave energy, and a second portion that is transparent to W band microwave energy. The second portion may be an insert that is secured to the radome at an opening formed therein. The insert may have a multi-layer structure with first, second and third layers, a fourth layer of foam between the first and second layers, and a fifth layer of foam between the second and third layers. The insert may include a plurality of spaced-apart, elongated reinforcing members or ribs between the first and second layers and between the second and third layers that extend along a longitudinal direction defined by the insert. The insert may have a serrated cross-sectional configuration.