Tilted-Boresight Antenna Array for Low-Complexity AESA Steering

Solution Overview

Problem

Two-dimensional active electronically scanned array (AESA) systems with a large number of individual antenna elements and transceiver modules become complex and expensive, making it difficult to achieve low-cost, lightweight performance while maintaining gain and side lobe performance.

Innovation Solution

The antenna array is split into two sub-antennas with tilted boresights, each comprising slotted waveguide antennas, allowing for a hybrid phased array system that combines passive and active electronic steering, reducing the number of transmit elements while maintaining directional accuracy and reducing radar cross-section errors.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a large number of individual antenna elements and transceiver modules are used in two-dimensional AESA systems, then directional accuracy and measurement precision are improved, but device complexity and cost increase significantly

Engineering Contradiction:

Improvedirectional accuracyVSAvoidsystem complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The antenna array is divided into two sub-antennas with tilted boresights, where each sub-antenna comprises multiple slotted waveguide antennas. This segmentation allows the system to achieve two-dimensional angular measurements by combining measurements from both sub-antennas, reducing the need for a full two-dimensional array of transceiver modules while maintaining measurement precision.

Inventive Principle:

Principle #1Segmentation

2Measurement precision

If a large number of individual antenna elements and transceiver modules are used in two-dimensional AESA systems, then directional accuracy and measurement precision are improved, but cost increases significantly

Engineering Contradiction:

Improvedirectional accuracyVSAvoidmanufacturing cost

Core Design Contradiction:

Measurement precisionVSEase of manufacture

Solution Approach 1:

The antenna array is divided into two sub-antennas with tilted boresights, where each sub-antenna comprises multiple slotted waveguide antennas. This segmentation allows the system to achieve two-dimensional angular measurements by combining measurements from both sub-antennas, reducing the need for a full two-dimensional array of transceiver modules while maintaining measurement precision.

Inventive Principle:

Principle #1Segmentation

3Device complexity

If the number of transmit elements is reduced to lower cost and weight, then device complexity and cost are reduced, but gain and side lobe performance deteriorate

Engineering Contradiction:

Improvesystem complexityVSAvoidantenna performance

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The two sub-antennas are configured with tilted boresights at different angles, creating an asymmetric geometry. This asymmetric arrangement allows the system to achieve two-dimensional measurement capability while using fewer transmit elements than a full two-dimensional array, thereby reducing complexity and cost while maintaining performance through the complementary measurement coverage of the tilted sub-antennas.

Inventive Principle:

Principle #4Asymmetry

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

This configuration enables cost-effective, low-weight angular measurements in two perpendicular directions, increasing range and accuracy, and reducing radar cross-section errors by simplifying the antenna design and maintaining high gain and low side lobe levels.

Implementation Method 1

The slotted waveguide emits linearly polarized radio waves directly through the slots

Methodology Applied

Scientific EffectElectromagnetic radiation: Electromagnetic Induction

Implementation Method 2

The beam can in this way be pointed in different directions by changing the phase of the individual antennas in the antenna array. This will in turn change the interference pattern of the antennas in the antenna array. In this way the direction of the boresight, resulting from constructive interference, can be changed

Methodology Applied

Scientific EffectInterference: Interference

Data Source

PatentUS11784403B2Antenna array and a phased array system with such antenna array

Publication Date: 2023.10.10 SAAB AB

AI summary

Antenna array and phased array system including a first and second antenna group, wherein the first antenna group includes two or more first antennas, and the second antenna group includes two or more second antennas, where in a first plane the one or more first and second antennas point in the same direction, and in a second plane, perpendicular to the first plane the one or more first antennas of the first antenna group are squinted by orientation away from the one or more second antennas of the second antenna group.