Antenna Test Apparatus Using Planar Wave Front Generation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current antenna testing methods, such as far-field and near-field measurements, face challenges like space requirements, interference from reflections and neighboring antennas, and the need for phase information, especially for active antennas, which complicates the measurement process and requires significant resources.
Innovation Solution
A measurement apparatus with a feed antenna comprising multiple radiating elements and an antenna feed system that adjusts phase and amplitude to create a substantially planar wave front at a predefined distance, allowing for far-field radiation pattern measurement without mirrors or mathematical conversions, enabling testing in a compact setup for both passive and active antennas.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If far-field measurements are performed in open air, then the radiation pattern can be measured at significant distance, but the measurements are affected by reflections from nearby bodies and interference from other antennas
Solution Approach 1:
The patent introduces a feed antenna system with multiple radiating elements as an intermediary device that generates a planar wave front in a controlled measurement zone. This mediator creates an artificial far-field environment within a compact space, eliminating the need for open-air measurements while avoiding reflections and interference from surrounding objects.
Solution Approach 2:
The patent changes the spatial distribution parameters of the radiating elements and their phase/amplitude characteristics to transform the spherical wave front into a planar wave front. By adjusting these parameters, the system creates a controlled electromagnetic environment that simulates far-field conditions in a compact near-field setup.
2Volume of stationary object
If near-field measurements are performed in a shielded anechoic chamber, then space requirements are reduced, but phase information is generally not available for active antennas and measurements require significant time
Solution Approach 1:
The patent divides the measurement system into multiple independent radiating elements that can be individually controlled and adjusted. This segmentation allows precise control over the wave front characteristics and enables the generation of planar waves without requiring full near-field scanning, thus providing phase information for active antennas while maintaining a compact setup.
Solution Approach 2:
The patent performs preliminary adjustment of the feed antenna system to pre-establish a planar wave front in the measurement zone before actual radiation pattern measurements are taken. This preliminary action eliminates the need for time-consuming near-field scanning and mathematical transformations, providing direct access to phase information.
3Measurement precision
If a compact range chamber with curved mirrors is used, then direct far-field measurement is enabled, but the chamber requires dimensions at least twice as large as the test antenna
Solution Approach 1:
The patent replaces the mechanical optical system of curved mirrors with an electromagnetic field-based solution using multiple controlled radiating elements. This substitution eliminates the need for large physical mirrors and their supporting structures, achieving far-field measurement capability in a compact space by electronically controlling the wave front shape.
4Measurement precision
If a compact range chamber with curved mirrors is used, then far-field measurement is possible, but the direct beam between feed antenna and test antenna disturbs the measurements
Solution Approach 1:
The patent creates a localized planar wave front in a specific measurement zone by precisely controlling the phase and amplitude distribution of individual radiating elements. This local quality control ensures that the planar wave is generated only in the required measurement area, eliminating direct beam interference while maintaining measurement accuracy.
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 solution allows for accurate far-field radiation pattern measurement of antennas in a compact setup, reducing space and interference issues, and does not require phase information, achieving results comparable to traditional methods while being cost-effective and adaptable to various antenna sizes and frequencies.
Implementation Method 1
The plurality of adjustment components adjusts the phase and amplitude of a wave front from a plurality of radiating elements such that the wave front is substantially planar at said predefined test distance
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
The present invention teaches a measurement apparatus for the measurement of a test antenna comprising: a movable stand for supporting the test antenna, a feed antenna having a plurality of radiating elements. The movable stand is located at a predefined distance from the feed antenna. An antenna feed system is provided with a plurality of adjustment components for adjusting the phase and amplitude of a wave front from the plurality of radiating elements such that at the distance the wave front is substantially planar.