Middle Field Antenna Pattern Correction for 5G Testing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional antenna array test and calibration methods are inefficient for integrated RF transceivers without RF connectors, especially for large antenna arrays used in 5G technology, due to the need for expensive and space-intensive far field test environments and time-consuming near field to far field mathematical transformations.
Innovation Solution
A test system using a probe antenna positioned in the middle field of the antenna array, which measures and corrects antenna patterns using a pre-populated correction table to derive far field patterns, eliminating the need for large test chambers and complex mathematical transformations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If far field test environment is used for large antenna arrays, then measurement accuracy is improved, but test chamber size and cost increase significantly
Solution Approach 1:
The patent transitions from conventional near-field to far-field measurement (one dimensional change in measurement plane) to middle-field measurement (introducing a new dimensional space between near and far fields). This middle field region allows far-field pattern measurement without requiring the probe to be positioned at the full far-field distance, thereby reducing the required test chamber size while maintaining measurement accuracy.
Solution Approach 2:
The patent changes the measurement parameter by introducing correction factors that account for the intermediate distance between near-field and far-field regions. By applying these correction factors to middle-field measurements, the system achieves far-field equivalent results without physically positioning the probe in the far-field region, thus reducing space requirements.
2Measurement precision
If near field to far field mathematical transformation is used, then far field patterns can be derived, but computational time and complexity increase
Solution Approach 1:
The patent performs preliminary measurements in the middle field region, which is closer to the antenna array than the far-field region. This preliminary measurement approach captures sufficient signal characteristics that can be directly transformed to far-field patterns with minimal computational processing, avoiding the need for complex near-field to far-field mathematical transformations.
Solution Approach 2:
The patent extracts only the essential measurement data needed for far-field pattern determination from the middle field region, rather than performing complete near-field scanning. By taking out only the necessary information at an intermediate distance, the system reduces computational complexity while maintaining measurement accuracy.
3Ease of operation
If conventional over-the-air testing is used for integrated RF transceivers, then connector requirements are eliminated, but test setup complexity increases for massive MIMO
Solution Approach 1:
The patent creates a universal test method that works for both conventional connector-based RF transceivers and integrated RF transceivers without connectors. The middle-field measurement approach is equally applicable to different antenna array configurations including massive MIMO systems, providing a multi-functional testing solution that simplifies the overall test setup complexity.
Data Source
AI summary
A method is provided for testing an antenna array of a DUT using a probe antenna, the antenna array including multiple antenna elements. The method includes providing a correction table that includes predetermined correction data of differences between far field antenna patterns from different positions in a far field of the antenna array and a middle field antenna pattern from a position in a middle field of the antenna array, where the middle field satisfies near field criteria for the antenna array and satisfies far field criteria for each antenna element in the antenna array; measuring an antenna pattern at a first position in the middle field of the antenna array; retrieving predetermined correction data from the correction table corresponding to a second position located in the far field of the antenna array; and translating the measured antenna pattern to the far field by adding the retrieved predetermined correction data.