Error correction techniques on bio-impedance measurements
AssigneeAnalog Devices International Unlimited Company
InventorsSriram GANESAN, Venugopal GOPINATHAN, Tony J. AKL
Life of this patent
Estimating the term…
Abstract
Determining bio-impedance of a body, or portion thereof, of a subject has been utilized for determining health characteristics (such as heart conditions) of the subject. The systems and procedures described herein may provide for correction and/or compensation for electrode contact impedance and for accurately determining bio-impedance. The system may take into account impedance sensitivity and/or frequency sensitivity when performing the bio-impedance determination to improve the bio-impedance determination.
Claims20
Circuitry for determining an amount of a bio-impedance of a portion of a body of a subject, the circuitry comprising:
- first impedance circuitry coupled to a first pin of the circuitry, the first pin to be coupled to a first side of the portion of the body, wherein the first impedance circuitry is to selectively couple a first impedance to the first pin;
- second impedance circuitry coupled to a second pin of the circuitry, the second pin to be coupled to a second side of the portion of the body, wherein the second impedance circuitry is to selectively couple a second impedance to the second pin;
- and
- voltage measurement circuitry coupled to the first pin and the second pin, the voltage measurement circuitry to:
- determine a first voltage difference between the first pin and the second pin with the first impedance coupled to the first pin and the second impedance decoupled from the second pin;
- and
- determine a second voltage difference between the first pin and the second pin with the first impedance decoupled from the first pin and the second impedance coupled to the second pin, the first voltage difference and the second voltage difference to be utilized for compensation for errors due to electrode contact impedance to determine the amount of the bio-impedance.
A system for determining a value of a bio-impedance of a portion of a body of a subject, comprising:
- a first electrode to be positioned on a first end of the portion of the body;
- a second electrode to be positioned on a second end of the portion of the body;
- and
- circuitry coupled to the first electrode and the second electrode, the circuitry to determine voltage differences between the first electrode and the second electrode, the circuitry comprising:
- first impedance circuitry coupled to the first electrode, the first impedance circuitry to selectively couple a first impedance between the first electrode and a ground of the circuitry;
- second impedance circuitry coupled to the second electrode, the second impedance circuitry to selectively couple a second impedance between the second electrode and the ground of the circuitry;
- and
- voltage measurement circuitry coupled to the first electrode and the second electrode, the voltage measurement circuitry to determine the voltage differences between the first electrode and the second electrode with selective coupling of the first impedance between the first electrode and the ground of the circuitry and selective coupling of the second impedance between the second electrode and the ground of the circuitry.
A process for determining a value of a bio-impedance of a portion of a body of a subject, comprising:
- determining, by circuitry, a first voltage difference between a first electrode positioned at a first end of the portion of the body and a second electrode positioned at a second end of the portion of the body with the circuitry having a first configuration;
- changing, by the circuitry, from the first configuration to a second configuration after the first voltage difference is determined;
- and
- determining, by the circuitry, a second voltage difference between the first electrode and the second electrode with the circuitry having the second configuration, the first voltage difference and the second voltage difference to be utilized for compensation to determine the value of the bio-impedance.
Dependencies are inferred from the claim text.