Compact Waveguide Antenna Array Feed Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing waveguide antenna feeds are bulky and difficult to adapt to larger arrays due to the need for extensive space for bends and twists, leading to high losses and limited scalability.
Innovation Solution
A compact waveguide corporate feed using E-plane tees and H-plane bends that couples signal ports to antenna ports with spacings less than one free-space wavelength, allowing for a scalable and reduced-size feed network that maintains constant thickness across various array sizes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If waveguide bends and twists are used to provide correct phasing, then proper signal distribution is achieved, but the feed structure becomes bulky and occupies large space
Solution Approach 1:
The patent transitions from using bends and twists (curved path in 3D space) to planar waveguide sections with E-plane and H-plane junctions (flat 2D layout). This dimensional change allows the feed network to achieve the required phase distribution without occupying large volumetric space, as the signal routing is accomplished through planar expansions and contractions rather than three-dimensional bends.
Solution Approach 2:
The patent changes the geometric parameters of the waveguide sections, specifically using expansions and contractions in the waveguide dimensions to achieve phase control. By varying the width and height of waveguide sections according to specific mathematical relationships, the effective electrical length and phase characteristics are controlled without requiring bulky bends or twists.
2Reliability
If waveguide feeds are designed for specific array sizes, then optimal performance is achieved, but adaptability to different array sizes is reduced
Solution Approach 1:
The patent creates a universal feed network design using modular E-plane and H-plane junctions that can be configured to serve multiple array sizes. The planar waveguide structure with adjustable expansion/contraction sections can be adapted to different numbers of antenna elements without requiring a complete redesign, making the feed system multi-functional across various array configurations.
Solution Approach 2:
The feed network is divided into modular segments or sections, each comprising specific E-plane and H-plane junctions. These segmented modules can be selectively combined or removed to accommodate different array sizes, providing scalability and adaptability while maintaining optimal performance characteristics for each configuration.
3Volume of moving object
If antenna elements are spaced closely to reduce array size, then compactness is improved, but grating lobes may be generated
Solution Approach 1:
The patent carefully controls the spacing parameter between antenna elements and the electrical length of each feed section to achieve sub-wavelength spacing without generating grating lobes. By adjusting the waveguide section dimensions and signal path lengths according to specific design criteria, the phase distribution is optimized to suppress grating lobe formation even at close element spacings.
Data Source
AI summary
A compact waveguide antenna array feed system provides antenna element ports spaced along an array face by less than one free-space wavelength in at least one dimension, while retaining a thickness in a direction perpendicular to the array face of less than one and one-half free-space wavelength.