Wireless ECG sensor system and method

• US 10,098,544 B2
• Filed: 03/11/2015
• Issued: 10/16/2018
• Est. Priority Date: 03/11/2015
• Status: Active Grant

• Current Assignee: Medicomp Incorporated (Medicomp, Inc. /Balda/)
• Original Assignee: Medicomp Incorporated (Medicomp, Inc. /Balda/)
• Inventors: Marcus, Sean, Chang, Chris, Baskerville, Scott
• Primary Examiner(s): Koharski, Christopher D
• Assistant Examiner(s): Bays, Pamela M
• Application Number:
  US14/644,300
• Publication Number:
  US 20160262619A1
• Time in Patent Office: 1,315 Days
• Field of Search: 600393
• CPC Class Codes: A61B 2560/0214 of power generation or supply
• CPC Class Codes: A61B 2560/0219 of externally powered implanted units
• CPC Class Codes: A61B 2562/08 Sensors provided with means for identification, e.g. barcodes or memory chips
• CPC Class Codes: A61B 5/0006 ECG or EEG signals
• CPC Class Codes: A61B 5/002 Monitoring the patient using a local or closed circuit, e.g. in a room or building A61B5/0017 takes precedence
• CPC Class Codes: A61B 5/0022 Monitoring a patient using a global network, e.g. telephone networks, internet
• CPC Class Codes: A61B 5/0024 for multiple sensor units attached to the patient, e.g. using a body or personal area network
• CPC Class Codes: A61B 5/259 using conductive adhesive means, e.g. gels
• CPC Class Codes: A61B 5/282 Holders for multiple electrodes for introduction into the body A61B5/287
• CPC Class Codes: A61B 5/303 Patient cord assembly, e.g. cable harness
• CPC Class Codes: A61B 5/316 Modalities, i.e. specific diagnostic methods
• CPC Class Codes: A61B 5/318 Heart-related electrical modalities, e.g. electrocardiography [ECG]
• CPC Class Codes: A61B 5/332 Portable devices specially adapted therefor
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/6833 Adhesive patches
• CPC Class Codes: A61B 5/6898 Portable consumer electronic devices, e.g. music players, telephones, tablet computers
• CPC Class Codes: A61B 5/7228 Signal modulation applied to the input signal sent to patient or subject; demodulation to recover the physiological signal modulation H03C
• CPC Class Codes: A61N 1/0492 Patch electrodes A61N1/0412, A61N1/0428 take precedence
• CPC Class Codes: A61N 1/3727 characterised by the modulation technique
• CPC Class Codes: A61N 1/37288 Communication to several implantable medical devices within one patient
• CPC Class Codes: G16H 10/60 : for patient-specific data, e.g. for electronic patient records
• CPC Class Codes: G16H 15/00 : ICT specially adapted for medical reports, e.g. generation or transmission thereof
• CPC Class Codes: G16H 40/67 : for remote operation
• CPC Class Codes: G16Z 99/00 : Subject matter not provided for in other main groups of this subclass

Abstract

A wireless ECG sensor system includes a sensor patch configured to attach to a user. The sensor patch may include a substrate having a positive and a negative electrode, and a passive radio-frequency identification (RFID) transponder carried by the substrate. The RFID may include a first antenna, a non-transitory and non-volatile storage medium in electrical communication with the first antenna, a load modulation switch in electrical communication with the first antenna, and a microcontroller in electrical communication with the first antenna and in data communication with both the storage medium and the load modulation switch. The system may also include an interrogator device having a second antenna configured to wirelessly transmit electromagnetic radiation having a resonant frequency of the first antenna of the sensor patch, and a demodulator configured to measure a voltage amplitude of the electromagnetic radiation wirelessly transmitted by the second antenna.

Claims

1. A wireless ECG sensor system comprising:

a sensor patch configured to attach to a user, the sensor patch comprising;

a substrate having first and second sections and configured to exhibit dielectric dispersion between the first and the second sections;

wherein a positive electrode is carried by the first section of the substrate, and

wherein a negative electrode is carried by the second section of the substrate; and

a passive radio-frequency identification (RFID) transponder carried by the substrate, and comprising;

a first antenna,

a non-transitory and non-volatile storage medium in electrical communication with the first antenna,

a load modulation switch in electrical communication with the first antenna, and

a microcontroller in electrical communication with the first antenna and in data communication with both the storage medium and the load modulation switch; and

an interrogator device separated from the sensor patch and configured to be carried by a housing, the interrogator device comprising;

a second antenna in electrical communication with a power source and configured to wirelessly transmit electromagnetic radiation having a resonant frequency of the first antenna of the passive RFID transponder; and

a demodulator configured to measure a voltage amplitude of the electromagnetic radiation wirelessly transmitted by the second antenna;

wherein the first antenna of the passive RFID transponder is configured to inductively receive power for operating the passive RFID transponder of the sensor patch from the electromagnetic radiation wirelessly transmitted by the second antenna of the interrogator device; and

wherein, upon receipt of power, the microcontroller of the passive RFID transponder is configured to receive a cardiac activity signal from at least one of the positive and negative electrodes of the sensor patch, to retrieve a location identifier from the storage medium of the passive RFID transponder, and to operate the load modulation switch of the passive RFID transponder to alter the voltage amplitude of the electromagnetic radiation to transmit to the demodulator a cardiac event reading comprising the cardiac activity signal and the location identifier.

2. The wireless ECG sensor system according to claim 1 wherein the sensor patch further comprises an analog-to-digital converter carried by the substrate;

wherein at least one of the positive and negative electrodes is configured to transmit the cardiac activity signal in analog format to the analog-to-digital converter; and

wherein the analog-to-digital converter is configured to convert the cardiac activity signal from analog format to digital format and to transmit the cardiac activity signal in digital format to the microcontroller.

3. The wireless ECG sensor system according to claim 1 wherein the sensor patch further comprises an amplifier and an analog-to-digital converter both carried by the substrate;

wherein at least one of the positive and negative electrodes is configured to transmit the cardiac activity signal in analog format to the amplifier;

wherein the amplifier is configured to amplify the cardiac activity signal to an amplified form to define an amplified cardiac activity signal, and to transmit the amplified cardiac activity signal to the analog-to-digital converter; and

wherein the analog-to-digital converter is configured to convert the amplified cardiac activity signal from analog format to digital format and to transmit the amplified cardiac activity signal in digital format to the microcontroller.

4. The wireless ECG sensor system according to claim 1 wherein the first antenna of the passive RFID transponder is configured to inductively receive power from the electromagnetic radiation wirelessly transmitted by the second antenna of the interrogator device when the second antenna is positioned a distance of less than one meter from the first antenna of the passive RFID transponder.

5. The wireless ECG sensor system of claim 1 wherein the electromagnetic radiation wirelessly transmitted by the second antenna is characterized by a frequency selected from the group consisting of LF band (120-150 kHz) and HF band (13.56 MHz).

6. The wireless ECG sensor system of claim 1 wherein the power source comprises at least one of a battery and a power cable.

7. The wireless ECG sensor system of claim 1 wherein the power inductively received by the first antenna of the passive RFID transponder comprises an AC input voltage;

wherein the passive RFID transponder of the sensor patch further comprises at least one of a converter and a regulator;

wherein the converter is configured to convert the AC input voltage to a DC output voltage;

wherein the regulator is configured to sustain the DC output voltage within a target DC bias range.

8. The wireless ECG sensor system according to claim 1 wherein the microcontroller of the passive RFID transponder is configured to store the cardiac activity signal on the storage medium of the passive RFID transponder.

9. The wireless ECG sensor system according to claim 1 wherein the first antenna of the passive RFID transponder is configured to receive the location identifier from the electromagnetic radiation wirelessly transmitted by the second antenna;

and wherein the microcontroller of the passive RFID transponder is configured to receive the location identifier from the first antenna of the passive RFID transponder and to store the location identifier on the storage medium.

10. The wireless ECG sensor system according to claim 1 wherein the first antenna of the passive RFID transponder is configured to receive a patch identifier from the electromagnetic radiation wirelessly transmitted by the second antenna;

and wherein the microcontroller of the passive RFID transponder is configured to receive the patch identifier from the first antenna of the passive RFID transponder and to store the patch identifier on the storage medium of the passive RFID transponder.

11. The wireless ECG sensor system according to claim 1 wherein the interrogator device further comprises a communications link in data communication with the demodulator and with at least one of a wired local area network (LAN) and a wireless LAN;

wherein the demodulator is configured to transmit the cardiac event reading to a computing system through the communications link.

12. The wireless ECG sensor system according to claim 11 wherein the computing system comprises a mobile phone.

13. The wireless ECG sensor system according to claim 11 wherein the sensor patch further comprises a plurality of sensor patches, each having a passive RFID transponder;

wherein the resonant frequency of the first antenna of each of the passive RFID transponders is configured to be distinct from the respective resonant frequency of the first antenna of each of the other passive RFID transponders; and

wherein the interrogator device is configured to wirelessly transmit electromagnetic radiation comprising a plurality of transmission frequencies such that at least one of the plurality of the transmission frequencies equals the respective resonant frequency of the first antenna of at least one of the passive RFID transponders.

14. The wireless ECG sensor system according to claim 13 wherein the computing system is configured to detect an arrhythmia from the cardiac event readings transmitted by at least one of the plurality of sensor patches.

15. The wireless ECG sensor system according to claim 13 wherein each of the plurality of sensor patches is configured to be positioned on the user according to an ECG electrode placement methodology selected from the group consisting of standard 3-lead (Einthoven'"'"'s Triangle), modified central lead (MCL1), standard 5-lead using Lead V1, standard 5-lead using Lead V5, EASI 5-lead, and interpolated 12-lead.