Cross-Dipole Radiating Elements for Reduced Multi-Band Scattering

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The challenge in designing multi-band base station antennas is the interaction between different arrays of radiating elements, which affects the shape and performance of antenna beams due to scattering and induced currents, particularly when operating in different frequency bands, leading to increased width and structural requirements.

Innovation Solution

The use of cross-dipole radiating elements with frequency selective surfaces that cancel currents induced by higher frequency bands while allowing current flow in the intended frequency band, reducing scattering and improving impedance matching.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If multiple arrays of radiating elements are deployed to support service in different frequency bands, then the number of supported frequency bands increases, but the antenna width and structural requirements increase

Engineering Contradiction:

Improvenumber of supported frequency bandsVSAvoidantenna width

Core Design Contradiction:

Adaptability or versatilityVSArea of stationary object

Solution Approach 1:

The patent combines multiple frequency band arrays into a single integrated antenna structure. The low-band, mid-band, and high-band arrays are merged into one antenna assembly, allowing multiple frequency bands to be supported without proportionally increasing antenna width. The arrays are positioned to overlap and share common structural support, achieving space efficiency through consolidation.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent arranges radiating element arrays in three-dimensional space rather than simple planar stacking. The low-band, mid-band, and high-band arrays are positioned at different depths and angles relative to the reflector, creating a volumetric configuration. This spatial arrangement allows frequency band multiplication without linear increases in antenna footprint width.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

2Adaptability or versatility

If different arrays of radiating elements are used for different frequency bands, then frequency band coverage increases, but scattering and induced currents between arrays increase

Engineering Contradiction:

Improvefrequency band coverageVSAvoidscattering and induced currents

Core Design Contradiction:

Adaptability or versatilityVSObject-generated harmful factors

Solution Approach 1:

The patent applies frequency-selective surface treatments to specific regions of the radiating elements. Each array's metallic surfaces are designed with local variations in conductivity and geometry that are optimized for its specific frequency band. The low-band elements have surface characteristics tuned for 694-960 MHz, mid-band for 1427-2690 MHz, and high-band for 3.3-4.2 GHz, reducing cross-band current induction through localized electromagnetic property control.

Inventive Principle:

Principle #3Local quality

3Productivity

If the number of base station antennas is increased to accommodate increasing volume of cellular communications, then communication capacity increases, but weight and wind loading constraints are exceeded

Engineering Contradiction:

Improvecommunication capacityVSAvoidantenna weight

Core Design Contradiction:

ProductivityVSWeight of stationary object

Solution Approach 1:

The patent creates a multi-functional antenna system where a single antenna structure performs the work of multiple separate antennas. The integrated low-band, mid-band, and high-band arrays are all supported by a common reflector and mounting structure. This universal design allows the antenna to provide service across multiple frequency bands and sectors, effectively increasing communication capacity without the weight penalty of multiple separate antenna installations.

Inventive Principle:

Principle #6Universality (Multi-functionality)

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 provides reduced scattering and enhanced suppression of higher band currents, resulting in improved antenna beam characteristics and reduced antenna width, thereby lowering tower leasing costs.

Implementation Method 1

currents induced on a first portion of the first metal region by RF energy emitted by the second radiating element substantially cancel currents induced on a second portion of the first metal region by the RF energy emitted by the second radiating element

Methodology Applied

Scientific EffectDestructive interference: Interference

Data Source

PatentUS12519250B2Cross-dipole radiating elements having frequency selective surfaces and base station antennas having such radiating elements

Publication Date: 2026.01.06 OUTDOOR WIRELESS NETWORKS LLC

AI summary

Antennas include a first radiating element that is configured to operate in a first operating frequency band, and a second radiating element that is configured to operate in a second operating frequency band that encompasses higher frequencies than the first operating frequency band. The first radiating element includes a first dipole radiator having first and second dipole arms and a second dipole radiator having third and fourth dipole arms. The first dipole arm includes a first metal region that substantially surrounds a first non-metal interior region, and the first non-metal interior region is configured so that currents induced on a first portion of the first metal region by RF energy emitted by the second radiating element substantially cancel currents induced on a second portion of the first metal region by the RF energy emitted by the second radiating element.