Method, medium, and apparatus for measuring heart rate

• US 20050215913A1
• Filed: 03/23/2005
• Published: 09/29/2005
• Est. Priority Date: 03/23/2004
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Bang, Sookwon, Lee, Hyoungki, Choi, Kiwan
• Granted Patent: US 9,649,038 B2
• Time in Patent Office: Days
• US Class Current: 600/500
• CPC Class Codes: A61B 5/02416 using photoplethysmograph signals, e.g. generated by infrared radiation A61B5/14552 takes precedence

Abstract

A method, medium, and apparatus for measuring a heart rate from blood flow in a blood vessel of a human body part, including: an amplifying circuit receiving a light signal reflected or penetrated from a human body part and generating a multi-stage amplified signal made up of a plurality of signals with a corresponding different gains; and a processor separating the multi-stage amplified signal into a plurality of channel signals having corresponding gains, reconfiguring the light signal using a channel signal selected among the plurality of channel signals and calculating the heart rate from the reconfigured light signal. Accordingly, it is possible to make an accurate measurement of a heart rate by minimizing effects of measuring environments. In addition, the apparatus, method, and medium are resistive to noise resulting from a movement of a human body part by comparing an optimum signal pattern and a correlation coefficient.

Claims

1. A heart rate measuring system, comprising:

an amplifying unit to receive a light signal reflection of a body and to generate a multi-stage amplified signal made up of a plurality of different corresponding signals with different gains; and

a processor to separate the multi-stage amplified signal into a plurality of channel signals and to calculate the heart rate from at least one of the channel signals.

2. The system of claim 1, wherein the plurality of different signals with different gains are selectively generated based upon a control signal.

3. The system of claim 1, wherein the light signal reflection is infrared or visible light.

4. The system of claim 1, further comprising:

an optical transmitting unit to output a light to the body; and

a detecting unit to detect a reflected light signal from the body.

5. The system of claim 4, wherein the detecting unit comprises:

an optical receiving unit to receive a reflected light signal and to detect an amplitude of the reflected light signal; and

a filter to filter an output of the optical receiving unit.

6. The system of claim 5, wherein the detecting unit further comprises an amplifier to amplify the filtered output of the optical receiving unit.

7. The system of claim 1, wherein the amplifying unit comprises:

an amplifier to amplify a difference between a signal input to a first input terminal and a signal input to a second input terminal;

a plurality of different resistances; and

a multiplexer transmitting a reflected light signal to a corresponding resistance, of the plurality of resistances, according to a control signal output from the processor,

wherein each of the plurality of resistances is positioned between the first input terminal and the multiplexer.

8. The system of claim 1, wherein the processor comprises:

a first signal reconfiguring unit to separate the multi-stage amplified signal into the plurality of channel signals, to divide each of the plurality of channel signals into segments, based on peak values of each corresponding channel signal, and to generate a first reconfigured light signal including a channel signal selected among the plurality of channel signals with regard to each segment;

a second signal reconfiguring unit to calculate a correlation coefficient from the first reconfigured light signal and a basic pattern and generating a second reconfigured light signal using the correlation coefficient; and

a heart rate calculating unit to compare the second reconfigured light signal with a reference correlation coefficient, and to calculate the heart rate based on a result of the comparison.

9. The system of claim 8, wherein each of the segments is a sector between a central point of an i-th peak point and a (i+1)-th peak point and a central point of a (i+1)-th peak point and a (i+2)-th peak point.

10. The system of claim 8, wherein the one channel signal has an unsaturated highest peak value in a corresponding segment.

11. The system of claim 1, wherein the processor comprises:

a signal reconfiguring unit to separate the multi-stage amplified signal into the plurality of channel signals, to divide each of the plurality of channel signals into segments, based on peak values of each corresponding channel signal, and to generate a reconfigured light signal including a channel signal selected among the plurality of channel signals with regard to each segment; and

a heart rate calculating unit to compare the reconfigured signal with a reference correlation coefficient, and to calculate the heart rate based on a result of the comparison.

12. The system of claim 11, wherein each of the segments is a sector between a central point of an i-th peak point and a (i+1)-th peak point and a central point of a (i+1)-th peak point and a (i+2)-th peak point.

13. The system of claim 11, wherein the one channel signal has an unsaturated highest peak value in a corresponding segment.

14. The system of claim 1, wherein the reflected light signal is a measure of light reflected off a blood vessel within the body and/or a measure of light permeability of the blood vessel.

15. The system of claim 1, wherein the body is a human body.

17. The system of to claim 13, wherein the processor comprises:

a signal reconfiguring unit to calculate a correlation coefficient from the reflection light signal and the basic pattern and to generate the reconfigured signal using the correlation coefficient; and

a heart rate calculating unit to compare the reconfigured signal with a reference correlation coefficient, and to calculate the heart rate based on a signal obtained from a result of the comparison.

16. A heart rate measuring system, comprising:

a detecting unit to detect a light signal reflection from a body; and

a processor to receive the reflection light signal from the detecting unit, to generate a reconfigured signal based on a correlation between the reflection light signal and a basic pattern, and to calculate the heart rate from the reconfigured signal.

18. A method of measuring a heart rate, comprising:

receiving a light signal reflection from a body;

generating a multi-stage amplified signal by separately amplifying the reflected light signal with a plurality of corresponding different gains;

separating the multi-stage amplified signal into a plurality of channel signals having corresponding gains; and

calculating the heart rate based on at least one of the channel signals.

19. The method of claim 18, wherein the generating of the multi-stage amplified signal comprises:

transmitting the reflected light signal to a first input terminal of an amplifier through channels, among a plurality of channels, based on a control signal, to generate the channel signals, respectively; and

amplifying a difference between the reflected light signal input to the first input terminal and a signal input to a second input terminal.

20. The method of claim 18, further comprising:

dividing each of the plurality of channel signals into segments, and generating a first reconfigured light signal including a channel signal selected among the plurality of channel signals with regard to each segment; and

generating a second reconfigured light signal based on a correlation between the first reconfigured signal and a basic pattern.

21. The method of claim 18, further comprising:

dividing each of the plurality of channel signals into segments, and generating a reconfigured signal including a channel signal selected among the plurality of channel signals with regard to each segment.

22. A method of measuring a heart rate, comprising:

receiving a light signal reflection from a body;

generating a reconfigured light signal based on a correlation between the reflected light signal and a basic pattern; and

calculating the heart rate from the reconfigured signal.

23. A medium comprising computer readable code implementing a method of measuring a heart rate, comprising:

receiving a light signal reflection from a body;

generating a multi-stage amplified signal by separately amplifying the reflected light signal with a plurality of corresponding different gains;

separating the multi-stage amplified signal into a plurality of channel signals, dividing each of the plurality of channel signals into segments, and generating a first reconfigured signal including a channel signal selected among the plurality of channel signals with regard to each segment;

generating a second reconfigured signal based on a correlation between the first reconfigured signal and a basic pattern; and

calculating the heart rate from the second reconfigured signal.

24. A medium comprising computer readable code implementing a method of measuring a heart rate, comprising:

receiving a light signal reflection from a body;

generating a multi-stage amplified signal by separately amplifying the reflected light signal, with a plurality of corresponding different gains;

separating the multi-stage amplified signal into a plurality of channel signals, dividing each of the plurality of channel signals into segments, and generating a reconfigured signal including a channel signal selected among the plurality of channel signals with regard to each segment; and

calculating the heart rate from the reconfigured signal.

25. A medium comprising computer readable code implementing a method of measuring a heart rate, comprising:

receiving a light signal reflection from a body;

generating a reconfigured signal based on a correlation between the reflected light signal and a basic pattern; and

calculating the heart rate from the reconfigured signal.