Half Vivaldi Antenna Parallel Configuration for 50-Ohm Impedance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Vivaldi antennas typically have a 100-ohm impedance, making it difficult to achieve direct feed from 50-ohm coaxial cables due to impedance mismatching issues, which limits bandwidth and efficiency in ultra-wideband applications.
Innovation Solution
The solution involves configuring Vivaldi antennas in parallel to achieve a 50-ohm impedance, allowing direct feeding with 50-ohm coaxial cables, and using additional elements like stub plates or reflectors to extend low frequency bandwidth and gain, eliminating the need for impedance matching networks.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a Vivaldi antenna with 100-ohm impedance is used, then the antenna structure is simple and broadband, but it cannot be directly fed by 50-ohm coaxial cables due to impedance mismatching
Solution Approach 1:
The patent combines multiple Vivaldi antenna elements in parallel to transform the impedance from 100 ohms to 50 ohms. Specifically, two 100-ohm Vivaldi antennas connected in parallel yield a combined impedance of 50 ohms, enabling direct compatibility with standard 50-ohm coaxial cable feed systems while preserving the broadband characteristics of the original antenna design.
2Ease of operation
If impedance matching networks or cavities are used to match 100-ohm antenna to 50-ohm cable, then feed compatibility is achieved, but device complexity increases and bandwidth is limited
Solution Approach 1:
The patent extracts and eliminates the need for complex impedance matching networks or cavities by directly incorporating parallel antenna elements that naturally provide the required 50-ohm impedance. This approach removes the matching network component entirely, simplifying the overall system while maintaining feed compatibility.
3Ease of operation
If impedance matching networks are used, then feed compatibility is achieved, but bandwidth is limited and efficiency is reduced
Solution Approach 1:
The patent merges multiple Vivaldi antenna elements in parallel configuration, which naturally transforms the impedance to 50 ohms without introducing bandwidth-limiting matching networks. This parallel combination maintains the broadband capability of the original antennas while achieving the required impedance match for standard coaxial cable feeding.
Data Source
AI summary
A single Vivaldi antenna plate (half Vivaldi antenna) over a ground plane can be used to achieve a 50-ohm impedance, or two or more single plates over a ground plane to achieve other impedances. Unbalanced 50-ohm transmission lines, e.g., coaxial cables, can be used to directly feed the antenna.