Fetal ECG Signal Separation via Maternal Subtraction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for monitoring fetal cardiac activity during pregnancy face challenges in accurately distinguishing fetal ECG signals from maternal ECG signals, especially during fetal movement, leading to noise contamination and reduced signal quality.
Innovation Solution
A computer-implemented method using ECG sensors positioned on the abdomen of a pregnant woman, which involves digital signal filtering, non-linear subtraction procedures, and Blind-Source-Separation algorithms to isolate and enhance fetal ECG signals, improving signal-to-noise ratio and allowing for real-time detection of fetal heart rate and variability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If non-invasive ECG sensors are used to monitor fetal cardiac activity, then fetal health monitoring is achieved, but maternal ECG signals contaminate the fetal ECG signals reducing measurement precision
Solution Approach 1:
The patent segments the composite ECG signal into distinct maternal and fetal components through digital signal processing. The method divides the signal processing into separate stages: maternal ECG detection, maternal ECG subtraction, and fetal ECG extraction. This segmentation allows independent optimization of each component's detection algorithm, improving overall measurement precision by treating the contamination problem as a separable signal decomposition task.
Solution Approach 2:
The patent extracts the maternal ECG signal from the composite signal and removes it to isolate the fetal ECG signal. The system detects maternal ECG peaks, reconstructs the maternal ECG waveform, and subtracts it from the composite signal. This extraction approach directly eliminates the harmful contamination effect, allowing clear fetal ECG detection without invasive procedures.
2Measurement precision
If signal processing algorithms are applied to separate fetal ECG from maternal ECG, then fetal signal detection accuracy improves, but device complexity increases
Solution Approach 1:
The patent performs preliminary detection and characterization of maternal ECG signals before attempting fetal ECG extraction. The system first identifies maternal ECG peaks, determines maternal heart rate, and reconstructs the maternal ECG waveform template. This preliminary action simplifies subsequent fetal ECG detection by pre-removing the dominant maternal signal component, reducing the complexity of the overall separation algorithm.
Solution Approach 2:
The patent uses an adaptive template matching approach as an intermediary step between raw signal acquisition and fetal ECG detection. The maternal ECG template serves as a mediator that bridges the composite signal and the isolated fetal signal. This intermediary representation simplifies the mathematical operations required for signal separation compared to direct blind source separation methods.
3Productivity
If real-time fetal ECG monitoring is implemented, then continuous fetal health assessment is achieved, but computational processing time increases
Solution Approach 1:
The patent applies partial processing by focusing computational resources on detecting and removing only the maternal ECG component rather than processing the entire composite signal for fetal ECG detection. By performing selective maternal ECG subtraction and then using simplified fetal peak detection on the cleaned signal, the system achieves real-time processing with reduced computational burden compared to full-signal analysis methods.
Solution Approach 2:
The patent uses periodic maternal ECG cycle detection to structure the signal processing in rhythmic intervals. By detecting maternal R-peaks and processing signals in cardiac cycle segments, the system transforms continuous processing into periodic batches. This approach allows efficient use of computational resources and enables real-time monitoring by processing signals in manageable periodic segments rather than continuous streams.
Data Source
Figure 1A~1B
Figure 2
Figure 3
AI summary
The invention provides systems and methods for monitoring the wellbeing of a fetus by the invasive detection and analysis of fetal cardiac electrical activity data.