Capacitive Difference ADC Feedback for Interferer-Resistant Biometrics
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Modern hospital patient monitoring systems face challenges in processing biometric signals, such as ECG signals, due to interference from large interferer signals, which affect signal precision and require high power consumption for accurate conversion.
Innovation Solution
A low power high precision mixed signal analog-to-digital converter system utilizing a capacitive difference circuit and sigma delta converter with a digital feedback loop, including a capacitive digital-to-analog converter, to remove interferer signals and amplify the biometric signal, allowing for high precision processing while minimizing power consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional ADC systems are used to process biometric signals in the presence of large interferer signals, then signal processing capability is maintained, but power consumption increases and measurement precision deteriorates
Solution Approach 1:
The patent extracts and removes the interferer signal from the biometric signal using a feedback loop that specifically targets and eliminates the dominant interference component, allowing the ADC to process only the cleaned biometric signal at lower power levels
Solution Approach 2:
The patent implements a feedback loop that continuously monitors the interferer signal and adjusts the cancellation in real-time, improving measurement precision by dynamically adapting to changing interference conditions while optimizing power consumption
2Measurement precision
If conventional ADC systems process biometric signals with large interferers, then signal conversion is performed, but measurement precision deteriorates due to interference
Solution Approach 1:
The patent converts the harmful interferer signal into a useful cancellation signal by capturing it through the feedback loop and using it to actively neutralize its own harmful effects on the biometric signal measurement
Solution Approach 2:
The patent introduces a feedback loop as an intermediary mechanism that mediates between the interferer signal and the biometric signal, allowing precise control and cancellation of interference without directly affecting the underlying biometric measurement
3Measurement precision
If high power is used for accurate signal conversion, then measurement precision is improved, but power consumption increases
Solution Approach 1:
The patent performs preliminary signal conditioning and interferer removal before the ADC conversion process, reducing the complexity and power requirements of the subsequent digital processing while maintaining high measurement precision
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system effectively removes interferer signals, enabling high precision biometric signal processing with reduced power consumption, maintaining signal quality and noise ratio, and allowing for cableless patient monitoring.
Implementation Method 1
a capacitive difference circuit that produces an analog difference signal by differencing an analog feedback loop signal and an input signal
Implementation Method 2
a capacitive digital-to-analog converter that is configured to produce the analog loop feedback signal based upon the digital version of the difference signal
Data Source
AI summary
A low power high precision mixed signal analog to digital converter is provided for processing biometric signals in the presence of a large interferer signal for cableless patient monitoring; a capacitive difference circuit produces an analog difference signal by differencing an analog feedback loop signal and an input signal; an analog-to-digital converter sigma delta converter produces a digital version of the difference signal, a digital feedback loop includes a digital integrator and a capacitive digital-to-analog converter configured to produce the analog loop feedback signal based upon the digital version of the difference.