Multi-Frequency Bio-Impedance Measurement for Blood Flow Analysis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing bio-impedance and bio-reactance measurement technologies are frequency-dependent, leading to variable interference and noise, resulting in inconsistent and inaccurate measurements of blood flow and body fluid levels due to tissue characteristics that change with frequency.
Innovation Solution
A non-invasive device and method using multiple alternating currents of different frequencies, processed using Inverse Fast Fourier Transforms (IFFTs) to measure tissue impedance and reactance across a wide frequency range, reducing quantization noise and enabling accurate calculation of bodily fluid and blood flow parameters through simultaneous amplitude and phase analysis.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single frequency alternating electrical current is used to measure bio-impedance and bio-reactance, then the measurement process is simple, but the measurements are frequency-dependent and result in poor measurements due to frequency-selective interference and non-linear tissue characteristics
Solution Approach 1:
The patent segments the measurement process by using multiple discrete frequency components (fundamental frequency and harmonic frequencies) to measure bio-impedance and bio-reactance separately at each frequency. This segmentation allows the system to identify and compensate for frequency-dependent variations in tissue characteristics, thereby improving measurement accuracy while maintaining manageable complexity through structured multi-frequency analysis
Solution Approach 2:
The patent changes the frequency parameter by measuring at multiple different frequencies (fundamental and harmonic) rather than a single frequency. This parameter variation enables the system to characterize tissue properties across a frequency spectrum, compensating for frequency-selective interference and non-linear tissue responses, thus improving measurement precision without excessively increasing system complexity
2Measurement precision
If multiple alternating currents of different frequencies are used to measure tissue impedance and reactance across a wide frequency range, then measurement accuracy and consistency are improved, but device complexity and signal processing requirements increase
Solution Approach 1:
The patent merges multiple frequency components (fundamental and harmonic alternating currents) into a single measurement system that processes all frequencies simultaneously. By combining these multi-frequency measurements in a unified bio-impedance and bio-reactance analysis framework, the system achieves high measurement accuracy across wide frequency ranges while managing device complexity through integrated signal processing rather than separate single-frequency systems
Solution Approach 2:
The patent adds the frequency dimension to the measurement by introducing harmonic frequencies alongside the fundamental frequency. This dimensional expansion from single-frequency to multi-frequency measurement enables comprehensive characterization of tissue properties, improving accuracy while the structured approach to frequency analysis keeps device complexity manageable through systematic processing of additional frequency dimensions
3Reliability
If frequency-selective interference and noise are present in bio-impedance measurements, then measurement consistency deteriorates, but the system complexity to compensate increases
Solution Approach 1:
The patent employs feedback mechanisms by measuring bio-impedance and bio-reactance at multiple frequencies and using these measurements to identify and compensate for frequency-selective interference patterns. The system continuously monitors the frequency-dependent variations and adjusts the analysis to maintain measurement consistency, thereby improving reliability while managing system complexity through targeted feedback-based compensation rather than overly complex correction systems
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
This approach provides more consistent and accurate measurements of blood flow and body fluid parameters by compensating for frequency dependencies, allowing for remote monitoring and improved disease diagnosis and treatment.
Implementation Method 1
Multiple alternating currents of different frequencies are generated using Inverse Fast Fourier Transforms (IFFTs). Multiple signals of different frequencies are summed in the frequency domain and are synchronously turned into a digital sequence in the time domain on all complete sinusoidal cycles of different frequencies using IFFTs.
Implementation Method 2
The measurements are frequency dependent. Some people incur different frequency-selective interference or noise than others when making the measurements. The frequency-selective impairments will result in poor measurements in some people.
Implementation Method 3
The multiple alternating currents are then injected into a human or animal body through electrodes and form a loop with external electrical parts. When the electrical currents are passing through the body, they are modulated by the body tissues and by the changes in those tissues.
Implementation Method 4
Even when the bodies or tissues are considered as conductance and capacitance (conductors and non-conductors), the tissues' characteristics are also frequency dependent. The tissues' integrated conductance and capacitance may not be linear along the frequency changes.
Data Source
AI summary
A method of calculating body fluid and blood flow in a human or animal body using multi-frequencies alternating electrical currents, determining the tissues' multi-frequency impedance and reactance changes, calculating the body fluid, blood flow and physiological parameter. With the simultaneous measurements of body's or tissues' impedance and reactance from multi-frequencies, it is possible either to compensate for the frequency-dependencies or to find the dependencies' cross relationship, and thus measure body fluid and blood flow more accurately.