IQ Signal Generator Feedback for Frequency-Dependent Sideband Suppression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for suppressing unwanted signal portions in IQ signals fail to adequately account for frequency-dependent errors, leading to incomplete suppression of sidebands.
Innovation Solution
An IQ signal generator system with integrated analysis and control modules determines error quantities based on a level function of a multi-tone signal, correcting IQ gain imbalances and quadrature errors without external measurement devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional static suppression techniques are used, then the suppression process is simple, but frequency-dependent errors are not adequately corrected leading to incomplete sideband suppression
Solution Approach 1:
The patent implements a feedback mechanism where the analysis module continuously monitors the modulated IQ signal and determines error quantities based on the level function. These error quantities are fed back to the control module which adjusts operational parameters of the baseband module and IQ modulator module, creating a closed-loop system that dynamically corrects frequency-dependent errors and achieves complete sideband suppression
Solution Approach 2:
The IQ signal generator system performs self-diagnosis and self-correction by integrating the analysis module and control module within the same system. The system automatically determines its own errors through the level function analysis and corrects them without requiring external measurement devices, enabling the system to service itself and achieve precise sideband suppression
2Measurement precision
If external measurement devices are used for error determination, then measurement accuracy may be improved, but costs and system complexity increase
Solution Approach 1:
The system uses its own internal resources (analysis module with level function determination) to measure and diagnose its own errors, eliminating the need for external measurement devices. The analysis module processes the modulated IQ signal internally to extract error information, achieving both measurement precision and system simplicity
Solution Approach 2:
The analysis module serves multiple functions: it monitors the signal level, determines the level function, extracts error quantities, and provides feedback for correction. This multi-functional component replaces what would traditionally require separate external measurement and analysis equipment, reducing overall system complexity while maintaining measurement precision
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
A method of suppressing unwanted signal portions in an IQ signal generated by an IQ signal generator system (12) is described. The method comprises the steps of - generating, by a baseband module (14), a baseband IQ signal, wherein the baseband IQ signal is a multi-tone signal; - modulating, by a IQ modulator module (16), the baseband IQ signal, thereby obtaining a modulated IQ signal; - determining, by an analysis module (30), a level function describing a signal level of the modulated IQ signal over time and/or over a phase of the multi-tone signal; - determining, by the analysis module (30), at least one error quantity based on the level function, wherein the at least one error quantity is indicative of at least one error in the IQ signal generator system; and - controlling, by a control module (34), the baseband module (14) and/or the IQ modulator module (16) in dependence of the at least one error quantity determined, thereby correcting the at least one error in the IQ signal generator system (12). Further, an IQ signal generator system (12) is described.