H-Shaped Mushroom Reflectarray for Independent TE TM Phase Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional reflectarrays face challenges in independently controlling the reflection phase of TE and TM incidence waves, achieving wide-angle control, maintaining capacitance unchanged with varying gap sizes, and supporting multiple frequencies, especially in dual polarization scenarios.

Innovation Solution

A reflectarray design utilizing H-shaped mushroom elements with symmetric patches, where the length of the inner patch is adjusted to change the reflection phase for one direction while keeping the outer patch lengths constant, allowing independent control of TE and TM wave reflection phases and maintaining capacitance consistency across varying gap sizes, enabling operation across multiple frequencies.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If conventional reflectarrays use 1/2 wavelength elements to control reflection phase, then the reflection phase can be adjusted by changing element size, but the structure becomes complex and cannot independently control TE and TM wave phases

Engineering Contradiction:
Improvereflection phase controlVSAvoidelement structure complexity
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The mushroom element is segmented into distinct components: a patch layer, a substrate, and a ground layer with via holes. This segmentation allows independent control of electrical parameters for TE and TM wave reflection phases while maintaining a relatively simple overall structure.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The invention transitions from conventional planar 1/2 wavelength elements to a three-dimensional mushroom structure with vertical via holes. This dimensional change enables independent phase control for orthogonal polarizations by adjusting via hole parameters (depth, diameter, spacing) without complicating the planar patch geometry.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Adaptability or versatility

If conventional reflectarrays use complex element shapes to support multiple frequency bands, then multiband operation is achieved, but manufacturing cost increases

Engineering Contradiction:
Improvefrequency band supportVSAvoidmanufacturing cost
Core Design Contradiction:
Adaptability or versatilityVSEase of manufacture

Solution Approach 1:

The mushroom element structure serves multiple functions: it provides reflection phase control for both TE and TM waves, supports wide-angle operation, and enables multiband operation. This is achieved through a single unified structure rather than requiring different element shapes for different bands, simplifying manufacturing.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

Multiband operation is achieved by changing electrical parameters of the mushroom elements (via hole depth, diameter, spacing, and patch dimensions) rather than changing the fundamental element geometry. This allows a single manufacturing process to produce elements that operate across multiple frequency bands.

Inventive Principle:
Principle #35Parameter changes

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 effectively reflects TE and TM waves in desired directions with independent phase control and stable capacitance, enhancing the reflectarray's ability to handle multiple frequencies and polarizations, improving communication efficiency and reliability.

Implementation Method 1

a reflectarray for reflecting a first polarized wave having an electric field component in parallel to a substrate surface and for reflecting a second polarized wave having an electric field component vertical to the substrate surface

Methodology Applied
Scientific EffectReflection: Reflection

Implementation Method 2

maintaining capacitance consistency across varying gap sizes, enabling operation across multiple frequencies

Methodology Applied
Scientific EffectCapacitance: Capacitance

Data Source

PatentEP2905840B1Reflect array
Publication Date: 2018.08.01 NTT DOCOMO INC
  • EP2905840B1 patent drawingFigure 1
  • EP2905840B1 patent drawingFigure 2
  • EP2905840B1 patent drawingFigure 3~3(4)

AI summary

One aspect of the present invention relates to a reflectarray having multiple elements arranged in an array, wherein each of the elements has a H-shaped patch provided in separation from a ground plate, the H-shaped patch is formed by four outer vertices defined by two rectangular outer patches and four inner vertices defined by an inner patch, a length of the inner patch with respect to a first direction is determined to change the reflection phase of an electric field incoming in parallel to the first direction while keeping positions of the four outer vertices and sizes of the outer patches constant, wherein the first direction is determined by positions of the four inner vertices, and a length of the H-shaped patch with respect to a second direction is determined to change the reflection phase of an electric field incoming in parallel to the second direction, wherein the second direction is determined by positions of the four outer vertices.