Array Antenna Calibration via Mutual Coupling Signal Ratio
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing array antenna systems face challenges in accurately calibrating transfer functions for each channel due to RF component characteristics, leading to inefficiencies in signal control and increased interference, particularly in digital beamforming systems.
Innovation Solution
A method and apparatus for efficiently calibrating array antennas by measuring signal loops with mutual coupling between antennas, calculating signal ratios, and performing amplitude and phase calibration using a processor and calibration circuit, allowing for row and column calibration without the need for additional hardware or costly chamber measurements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional transfer function calibration methods are used for each channel, then measurement accuracy may be maintained, but device complexity and calibration time increase significantly
Solution Approach 1:
The calibration process is segmented into two distinct phases: a one-time comprehensive calibration that characterizes mutual coupling effects, and subsequent efficient calibrations that leverage pre-stored calibration data. This segmentation allows the system to maintain high measurement precision while reducing the complexity and time of routine calibration operations.
Solution Approach 2:
The patent performs preliminary calibration measurements to characterize mutual coupling effects between antenna elements before actual operation. These preliminary results are stored and reused in subsequent calibration processes, eliminating the need to repeatedly measure the same coupling effects and significantly reducing calibration time and complexity.
2Manufacturing precision
If comprehensive calibration of all antenna channels is performed, then signal control accuracy improves, but calibration time and resource consumption increase
Solution Approach 1:
The system performs comprehensive calibration measurements in advance to capture mutual coupling characteristics, storing these results for future use. This preliminary action ensures high signal control accuracy is achieved while subsequent calibrations require minimal time by leveraging the pre-acquired data.
Solution Approach 2:
The patent creates a copy of the mutual coupling calibration data and stores it for reuse. Instead of repeatedly performing time-consuming comprehensive measurements, the system copies and applies the previously measured coupling characteristics to multiple calibration scenarios, significantly reducing calibration time while maintaining accuracy.
3Device complexity
If mutual coupling between antennas is not considered in calibration, then calibration process is simplified, but beamforming accuracy deteriorates
Solution Approach 1:
The patent extracts the mutual coupling effects from the overall calibration process by measuring and characterizing them separately. This extraction allows the system to account for coupling effects independently, improving beamforming accuracy without significantly increasing the complexity of the main calibration procedure.
Solution Approach 2:
The patent introduces mutual coupling calibration data as an intermediary element that mediates between the antenna elements and the beamforming algorithm. This intermediary information allows the system to compensate for coupling effects and improve beamforming accuracy without requiring complex real-time measurements during operation.
4Measurement precision
If expensive anechoic chamber measurements are used for calibration, then measurement accuracy improves, but cost and accessibility worsen
Solution Approach 1:
The patent enables the array antenna system to perform self-calibration using built-in test signals and internal measurement capabilities. This self-service approach eliminates the need for expensive external anechoic chamber facilities, making accurate calibration accessible and cost-effective while maintaining measurement precision through automated mutual coupling characterization.
Data Source
AI summary
An array antenna system, and a calibration method and apparatus thereof are provided. The calibration method includes measuring a signal loop including mutual coupling between antennas included in an array antenna, calculating a ratio of a reception (RX) signal received by each antenna to an RX signal received by a reference antenna of the array antenna based on a result of the measuring, and performing calibration of the array antenna based on the ratio.