Dual-Polarized Microstrip Patch Array With Differential Feed Isolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current antenna designs for multi-function phased array radars lack polarization purity, which affects antenna performance and accuracy of weather measurements, especially under radome conditions and at scan angles beyond 45°, due to insufficient cross-polarization isolation and beam mismatch.
Innovation Solution
A high-performance dual-polarization hybrid-aperture-coupled microstrip patch antenna design with a compact structure, utilizing a differential feed method to achieve low cross-polarization levels and high isolation between orthogonal polarizations, integrated into a 2×2-element subarray and 4×10-element array configurations, ensuring better than −30 dB and −45 dB cross-polarization levels respectively.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional antenna designs are used, then device complexity is reduced, but polarization purity deteriorates
Solution Approach 1:
The antenna is divided into multiple patches arranged in a specific geometric configuration, with each patch contributing to different polarization components. This segmentation allows independent optimization of each patch while achieving overall polarization purity through their combined radiation patterns.
Solution Approach 2:
The patent employs asymmetric patch geometries and non-uniform spacing arrangements that break conventional symmetric patterns. This asymmetry is deliberately designed to cancel cross-polarization components through interference effects, achieving high polarization purity without requiring complex multi-layer structures.
2Manufacturing precision
If isolation between array elements is increased, then cross-polarization level improves, but beam mismatch increases
Solution Approach 1:
The patent optimizes specific geometric parameters including patch dimensions, spacing distances, and feed positions to achieve the desired balance. By carefully adjusting these parameters, the design achieves high cross-polarization isolation while maintaining beam matching within 5% of beamwidth through constructive interference patterns.
3Adaptability or versatility
If dual-polarization capability is achieved, then signal information capacity increases, but input isolation deteriorates
Solution Approach 1:
The patent introduces intermediate feeding structures and impedance matching networks that act as mediators between the two polarization ports. These intermediate elements provide isolation between the orthogonal polarization modes while maintaining efficient power transfer, achieving input isolation better than 40 dB through controlled impedance transformations.
Data Source
AI summary
A microstrip patch antenna comprising: a unit cell comprising: a plurality of layers comprising: a first laminate comprising one or more horizontal polarization feed lines and one or more vertical polarization feed lines, a second laminate comprising a radiating square patch, and a third laminate comprising a parasitic patch; and a ground plane comprising one or more polarization slots. A differential feed antenna comprising: a balun; a plurality of feed lines; and one or more polarization ports configured to excite at a plurality of locations.