Isotropic Antenna Array Azimuth-Independent Impedance Matching

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Large planar antenna arrays face difficulties in optimizing electronic circuits for scanning in all directions due to the dependency on both azimuth and elevation angles, making complex circuit optimization impractical.

Innovation Solution

A large periodic array of ideally isotropic dipole antenna elements with a wired substrate, allowing for electronic beam scanning independent of azimuth angles, using a control circuit and power coupling modules to match resistance to the signal source based on elevation angles only.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If conventional planar antenna arrays are used for scanning in all directions, then scanning coverage is improved, but circuit optimization complexity increases significantly

Engineering Contradiction:

Improvescanning coverageVSAvoidcircuit optimization complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent changes the fundamental radiation pattern parameter from conventional directional patterns to isotropic radiation pattern. By making each antenna element radiate equally in all directions (isotropic), the impedance becomes independent of azimuth angle, reducing the optimization variables from two angles (θ and φ) to one angle (θ only), thus simplifying circuit optimization while maintaining full-direction scanning capability

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent employs composite material structures including artificial magnetic conductors (AMC) and artificial electric conductors (AEC) to achieve the isotropic radiation pattern. These composite materials with specific electromagnetic properties enable the antenna elements to radiate isotropically, solving the contradiction between scanning coverage and circuit complexity

Inventive Principle:

Principle #40Composite materials

2Device complexity

If isotropic antenna elements are used, then impedance matching is simplified, but achieving ideal isotropic radiation becomes challenging

Engineering Contradiction:

Improveimpedance matching complexityVSAvoidisotropic radiation characteristic

Core Design Contradiction:

Device complexityVSManufacturing precision

Solution Approach 1:

The patent introduces artificial magnetic conductors (AMC) and artificial electric conductors (AEC) as intermediary structures between the antenna elements and free space. These intermediary materials with engineered electromagnetic properties facilitate the achievement of isotropic radiation by controlling the interaction between the antenna elements and the surrounding environment, making the isotropic radiation characteristic achievable in practice

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS8482479B2Azimuth-independent impedance-matched electronic beam scanning from a large antenna array including isotropic antenna elements

Publication Date: 2013.07.09 POLYTECHNIC INSTITUTE OF NEW YORK UNIVERSITY

AI summary

A large periodic array of ideally isotropic antenna elements permits electronic beam scanning and has a performance of power coupling from signal sources at the antenna inputs which is independent of the azimuth (Φ) scanning direction, dependent only on one spatial variable (elevation angle, θ) of scanning Such performance from an antenna array normally can not be achieved using conventional designs. Such an antenna array may be used in communications and radars.