Multiport Amplifier Test Injection for Phase Tracking Calibration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Multiport amplifiers (MPAs) operating at high frequencies, such as Ku and Ka bands, face challenges in maintaining stable phase and amplitude tracking between amplifier units over time, leading to potential interference due to long-term drift and imbalances, necessitating calibration adjustments during the satellite's lifetime.
Innovation Solution
A method and system for applying test signals directly between the input network and amplifier units in a multiport amplifier arrangement, allowing for measurement at any output port and enabling calibration of specific amplifier paths by comparing reference and calibration paths, thereby determining gain and phase adjustments to improve port-to-port isolation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional on-board test signal generation and monitoring is used, then MPA calibration can be performed, but the device complexity and testing requirements increase significantly
Solution Approach 1:
A ground-based test signal generator acts as an intermediary, replacing complex on-board test equipment. The ground station generates test signals that are transmitted to the satellite, where they are processed by the MPA and the returned signals are analyzed for calibration purposes, eliminating the need for sophisticated on-board test signal generation and measurement equipment
Solution Approach 2:
The patent replaces the mechanical/electrical test equipment system on-board with a ground-based electronic system. By using ground-based signal generation and analysis equipment, the complexity is shifted from the satellite to the ground station, where resources are more abundant and maintenance is more accessible
2Measurement precision
If accurate gain and phase measurements are performed at output ports, then precise calibration is achieved, but the measurement precision requirements increase the difficulty of detecting and measuring
Solution Approach 1:
The ground station serves as an intermediary measurement system, providing the sophisticated measurement capabilities needed for accurate gain and phase detection. The satellite simply transmits and receives signals, while the complex measurement and analysis functions are performed on the ground where appropriate equipment is available
Solution Approach 2:
Instead of measuring signals directly at the MPA output ports on-board, the system inverts the approach by transmitting test signals from ground to satellite and measuring the returned signals. This reversal allows using ground-based measurement equipment to achieve precise calibration without requiring complex on-board measurement systems
3Manufacturing precision
If MPA is aligned on ground initially, then initial performance is optimized, but long-term performance drift requires additional calibration during satellite lifetime
Solution Approach 1:
The MPA is pre-aligned on the ground with high precision before satellite deployment, establishing optimal initial performance. The ground-based calibration system captures the MPA's characteristics at launch, and this preliminary calibration data is used to compensate for long-term drift throughout the satellite's operational lifetime
Solution Approach 2:
The system implements long-term feedback calibration by periodically transmitting test signals and analyzing the returned signals to detect performance drift. Based on the measured deviations from the initial ground alignment, correction parameters are calculated and applied to restore optimal MPA performance, creating a closed-loop feedback system that maintains precision over time
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
The invention provides a method and apparatus for applying test signals to a multiport amplifier (MPA) and a method, apparatus and system for determining parameter adjustments for an MPA. Applying test signals to an MPA is performed so as to provide an output signal indicative of parameter adjustments for the MPA, the multiport amplifier arrangement comprising an input network, an amplifier unit and an output network, where the method includes providing a test signal directly to a point in the multiport amplifier arrangement between an output of the input network and an input of the amplifier unit. The method of determining parameter adjustments for a multiport amplifier arrangement includes receiving first and second output signals associated with an output of the multiport amplifier arrangement, the first output signal corresponding to a first signal path through the multiport amplifier arrangement and the second output signal corresponding to a second signal path through the multiport amplifier arrangement and determining parameter adjustments based on the first and second output signals.