KR20220053847A - Oxygen saturation measuring method based on independent componet analysis technique and apparatus therefore - Google Patents

Abstract

Disclosed are an oxygen saturation measurement method on the basis of an independent component analysis (ICA) technique to increase measurement accuracy of oxygen saturation and an apparatus thereof. According to one embodiment of the present invention, the oxygen saturation measurement method comprises the following steps: acquiring a received signal including an infrared signal and red signal passing passed through a user's body; separating the infrared signal and the red signal from the acquired received signal; removing noise commonly applied to the separated infrared and red signals; and calculating an oxygen saturation value of the user by using the noise-removed infrared signal and red signal. The separation step separates the infrared signal and the red signal from the received signal by using the ICA technique.

Description

OXYGEN SATURATION MEASURING METHOD BASED ON INDEPENDENT COMPONET ANALYSIS TECHNIQUE AND APPARATUS THEREFORE

The present invention relates to a technique for measuring oxygen saturation based on an independent component analysis technique, and more particularly, a method for measuring oxygen saturation based on an independent component analysis technique capable of measuring oxygen saturation based on an independent component analysis technique (ICA); It's about the device.

As personalization and aging progress, individuals are paying more attention to their own health and performing regular health check-ups. However, since it is inconvenient to have to pay extra time for a health check-up, most of them visit a hospital when there is a health problem. However, it is inconvenient to visit the hospital for the elderly or the disabled who are inconvenient in movement or have chronic diseases, and it is possible to cope with dangerous situations only by periodically checking the state of the body (that is, the state of the body).

Oxygen saturation measurement is widely used as a measurement target for personal health. The oxygen saturation measurement measures the light absorption for each wavelength by the pulsation component of arterial blood to non-invasively calculate the blood oxygen saturation (SpO2).

SUMMARY Embodiments of the present invention provide a method and apparatus for measuring oxygen saturation based on an independent component analysis technique capable of measuring oxygen saturation based on an independent component analysis (ICA) technique.

A method for measuring oxygen saturation according to an embodiment of the present invention is a method for measuring oxygen saturation, the method comprising: obtaining a reception signal including an infrared signal and a red signal passing through a user's body; separating an independent infrared signal and a red signal from the obtained received signal; removing noise commonly applied to the separated infrared signal and red signal; and calculating the oxygen saturation value of the user using the infrared signal and the red signal from which the noise has been removed.

In the separating step, an independent infrared signal and a red signal may be separated from the obtained received signal using Independent Component Analysis (ICA).

In the removing of the noise, the noise signal commonly applied to the separated infrared signal and the red signal is separated using an independent component analysis technique, and then the separated noise signal is removed using an adaptive filter. can

In the calculating of the user's oxygen saturation value, a photoplethysmography (PPG) signal may be obtained by removing the noise, and the user's oxygen saturation value may be calculated using the obtained photoplethysmography signal.

An apparatus for measuring oxygen saturation according to an embodiment of the present invention is an apparatus for measuring oxygen saturation, comprising: an acquisition unit configured to acquire a reception signal including an infrared signal and a red signal that have passed through a user's body; a separation unit for separating an independent infrared signal and a red signal from the obtained received signal; a removal unit for removing noise commonly applied to the separated infrared signal and red signal; and a calculator configured to calculate the user's oxygen saturation value by using the noise-removed infrared signal and the red signal.

The separation unit may separate an independent infrared signal and a red signal from the obtained received signal by using an independent component analysis (ICA) technique.

The remover may use an independent component analysis technique to separate a noise signal commonly applied to the separated infrared signal and a red signal, and then remove the separated noise signal using an adaptive filter.

The operation unit may remove the noise to obtain a photoplethysmography (PPG) signal, and calculate the oxygen saturation value of the user by using the obtained photoplethysmography signal.

According to embodiments of the present invention, oxygen saturation may be measured based on Independent Component Analysis (ICA).

According to embodiments of the present invention, by measuring the oxygen saturation value using the independent component analysis technique, it is possible to improve the accuracy of the oxygen saturation measurement value.

1 shows the configuration of a ring-shaped oxygen saturation measuring device.
2 shows an exemplary view for explaining a semi-convex lens applied to a light transmitting unit and a light receiving unit.
3 is a picture showing a state in which the device of FIG. 1 is worn on a user's finger.
4 is a flowchart illustrating an operation of a method for measuring oxygen saturation based on an independent component analysis technique according to an embodiment of the present invention.
5 is a diagram illustrating an example for explaining the method of FIG. 4 .
6 shows the configuration of an apparatus for measuring oxygen saturation based on an independent component analysis technique according to an embodiment of the present invention.

Advantages and features of the present invention and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be embodied in various different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the art to which the present invention pertains It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims.

The terminology used herein is for the purpose of describing the embodiments, and is not intended to limit the present invention. In this specification, the singular also includes the plural unless specifically stated otherwise in the phrase. As used herein, "comprises" and/or "comprising" refers to the presence of one or more other components, steps, operations and/or elements mentioned. or addition is not excluded.

Unless otherwise defined, all terms (including technical and scientific terms) used herein may be used with the meaning commonly understood by those of ordinary skill in the art to which the present invention belongs. In addition, terms defined in a commonly used dictionary are not to be interpreted ideally or excessively unless specifically defined explicitly.

Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings. The same reference numerals are used for the same components in the drawings, and repeated descriptions of the same components are omitted.

SUMMARY Embodiments of the present invention provide a method and an apparatus for measuring oxygen saturation based on Independent Component Analysis (ICA).

At this time, the device applied to the present invention can measure oxygen saturation in daily life while wearing it, and detect a signal stably by attaching the light transmitting unit and the light receiving unit to the skin surface in contact with the user's finger regardless of the thickness of the finger. Thus, the measurement accuracy of oxygen saturation can be improved. For example, the device applied to the present invention can reduce the driving current of the diode, that is, the light transmitter and the light receiver by 50% by applying a semi-convex lens to the light transmitter and the light receiver, and regardless of the thickness of the finger, the skin surface in contact with the finger Adjusting means that can adjust the elastic force of the curved shape that can adjust the adhesion so as to be in close contact with, for example, it may be provided with a contact part.

The present invention will be described with reference to FIGS. 1 to 6 as follows.

Fig. 1 shows the configuration of a ring-shaped oxygen saturation measuring device. Fig. 1a is a front view of the ring-shaped oxygen saturation measuring device, and Fig. 1b is a perspective view of the ring-shaped oxygen saturation measuring device. .

Referring to FIG. 1 , a ring-shaped oxygen saturation measuring apparatus 100 includes a main body 110 , a first body part 120 , a second body part 130 , a contact part 140 , a light transmitting part 150 and a light receiving part. (160).

The main body 110 controls the light transmitting unit 150 and the light receiving unit 160 , and measuring the oxygen saturation of the user based on the output signal of the light receiving unit 160 that receives the light transmitted by the light transmitting unit 150 . contains modules.

At this time, the main body 110 further includes a charging terminal 111 for charging the built-in battery of the main body using an external charging means and a display means (not shown) for displaying the user's oxygen saturation measured by the measurement module. can be provided Here, the charging terminal may be configured in the form of a terminal corresponding to the form of a cable with the charging means.

The body 110 may be electrically connected to the light transmitting unit 150 and the light receiving unit 160 disposed on the inner surfaces of the first body unit 120 and the second body unit 130 , and the electrical connection is the embodiment of the present invention. It may be determined by a business operator or an individual providing the technology, and a detailed description thereof will be omitted because the corresponding part may confuse the technical gist of the present invention.

The first body part 120 is formed to contact at least a part of the skin surface of the user's finger inserted into the device 100 . For example, the first body portion is physically connected to the body and is formed of an elastic material on the left side, and any one of the light transmitting unit 150 and the light receiving unit 160 is formed or disposed on the inner surface of the first body 130 . can

The second body 130 is formed to contact at least another partial skin surface of the user's finger inserted into the device 100 . For example, the second body part 130 is physically connected to the body 110 and is formed of an elastic material on the right side, and among the light transmitting part 150 and the light receiving part 160 on the inner surface of the second body part 130 . Either the other may be formed or disposed.

The contact portion 140 is connected to the end of the first body portion 120 and the end of the second body portion 130 , and the gap between the first body portion 120 and the second body portion 130 is elastically formed. to bring the first body part 120 and the second body part 130 into close contact with the user's finger contact skin surface regardless of the thickness of the user's finger.

At this time, the contact portion 140 is connected to the terminal end of the first body portion 120 and the terminal end of the second body portion 130 is formed in a 'U'-shaped curved shape, it can be formed of an elastic material. there is. Of course, the contact part is not limited to a 'U'-shaped curved shape, and the first body part 120 and the second body part 130 can be brought into close contact with the skin surface of the user's finger regardless of the thickness of the user's finger. It can be formed into all possible shapes.

Although the first body part 120 , the second body part 130 and the contact part 140 have been described as independent configurations, the first body part 120 , the second body part 130 and the contact part 140 . is not limited or limited to being independently configured, and the first body part 120 , the second body part 130 and the contact part 140 may be integrally formed of an elastic material, for example, a silicone material. That is, the first body portion 120 , the second body portion 130 , and the contact portion 140 may be integrally formed in a ring shape.

The light transmitting unit 150 is a means for emitting light, and includes a diode (eg, a light emitting diode) emitting infrared light and a specific color, for example, red light, and a half as shown in FIG. 2 on the upper part of the diode. A convex lens is formed.

Here, the light transmitting unit 150 may be disposed on the inner surface of any one of the first body portion 120 and the second body portion 130 , and the infrared and red light emitted through the semi-convex lens transmits the finger. Thus, it can be transmitted to the light receiving unit.

At this time, as shown in FIG. 2 , the semi-convex lens may include a primary refractive surface 151 formed as a concave surface with respect to the diode and a secondary refractive surface 152 formed as an outwardly convex convex surface. . For example, the light emitted by the light transmitting unit 150 is spread in all directions through the primary refractive surface 151 of the semi-convex lens, and the light spread in this way passes through the secondary refractive surface 152 convexly formed in the outward direction. It spreads once more. That is, the light refracted in a direction to diffuse while passing through the primary refracting surface 151 is refracted in a direction to be diffused once again while passing through the secondary refracting surface 152. will do

Here, the radius of curvature of the primary refractive surface 151 of the semi-convex lens may be larger than the radius of curvature of the secondary refractive surface 152 .

The light receiving unit 160 is a means for receiving light, and the infrared light transmitted from the light transmitting unit 150 and a specific color, for example, red light, pass through the user's finger, and receive the transmitted light.

In this case, the light receiving unit 160 may include a photodiode and a semi-convex lens shown in FIG. 2 . That is, the light receiving unit 160 has a semi-convex lens formed on the photo diode.

Here, the light receiving unit 160 may be disposed on the inner surface of the other of the first body portion 120 and the second body portion 130 , and the infrared and red light received through the semi-convex lens are received by the photodiode. can be

At this time, the light receiving unit 160 collects the light that has passed through the finger through the secondary refractive surface of the semi-convex lens and then focuses it again through the primary refractive surface. That is, since the light that is focused while passing through the secondary refracting surface is again focused while passing through the primary refracting surface, as a result, the light is focused and bent twice and is received by the photodiode. Similarly, the radius of curvature of the primary refractive surface of the semi-convex lens applied to the light receiving unit 160 may be formed to be larger than the radius of curvature of the secondary refractive surface.

As shown in FIG. 3 , the ring-shaped oxygen saturation measuring device 100 is applied to the skin surface of the user's finger contact, which is worn regardless of the thickness of the user's finger by adjusting the elastic force by the contact part when it is applied to the user's finger. By close contact, the light emitted by the light transmitting unit 150 passes through the finger and is received by the light receiving unit 160, so the user's oxygen saturation can be measured using the optical signal received from the measuring module to the light receiving unit 160 there is.

That is, the ring-shaped oxygen saturation measuring device elastically holds the first body part 120 and the second body part 130 according to the thickness of the user's finger to which the device is fitted by the contact part 140 , The inner surfaces of the body part 120 and the second body part 130 are brought into close contact with the skin surface in contact with the user's finger regardless of the thickness of the user's finger, and thus the light transmitting unit and the light receiving unit are in close contact with the skin surface in contact with the finger to measure the signal. accuracy can be improved.

In addition, by applying the semi-convex lens shown in FIG. 2 to the light transmitting part and the light receiving part, the ring-shaped oxygen saturation measuring device can reduce the driving current of the diode by 50% and drive the device with low power, It is possible to live a lifetime while wearing it without a separate cable.

In addition, since the first body part 120 and the second body part 130 of the ring-shaped oxygen saturation measuring device are physically connected to the body 110 , they may perform a function of supporting the body.

The present invention is a technology for measuring oxygen saturation of a user wearing such a device, and is not limited or limited to the above-described ring-shaped oxygen saturation measuring device, and a light transmission signal including an ultraviolet signal and a red signal is an example of the user's body. For example, after acquiring a received signal that is received through a finger, that is, a received signal including an infrared signal and a red signal that has passed through the user's body, all types of which can measure the user's oxygen saturation value through these received signals can be applied to the device.

4 is a flowchart illustrating an operation of a method for measuring oxygen saturation based on an independent component analysis technique according to an embodiment of the present invention.

Referring to FIG. 4 , the oxygen saturation measurement method according to an embodiment of the present invention obtains a reception signal including an infrared signal (IR signal) and a red signal (RD signal) that have passed through the user's body (S410).

Here, in step S410, a received signal may be obtained through the light receiving unit illustrated in FIG. 1 .

When the received signal including the IR signal and the RD signal is obtained in step S410, the IR signal and the RD signal that have passed through the user's body are separated from the obtained received signal (S420).

In this case, in step S420, the IR signal and the RD signal included in the received signal may be separated using an independent component analysis technique (ICA), and the separated IR signal and the RD signal include a noise signal. .

For example, in step S420, the received signal may be divided into an IR signal including noise and an RD signal as shown in FIG. 5A using ICA.

When the IR signal including noise and the RD signal including noise are separated by step S420, noise commonly applied to the separated IR signal and the RD signal is removed (S430).

Here, in step S430, a noise signal commonly applied to the separated IR signal and the RD signal may be separated using ICA, and the separated noise signal may be removed using a filter, for example, an adaptive filter. can do.

For example, in step S430, when a noise signal commonly applied to the separated IR signal and the RD signal is separated as shown in FIG. 5B, the noise signal may be removed using an adaptive filter.

When the noise signal commonly applied to the IR signal and the RD signal is removed by step S430, the user's oxygen saturation value is calculated using the noise-removed IR signal and the RD signal (S440).

At this time, in step S440, as shown in FIG. 5c, a photoplethysmography (PPG) signal from which noise has been removed by step S430 may be acquired, and the user's oxygen saturation value using the noise-removed PPG signal. can be calculated.

Here, in step S440, the user's oxygen saturation value may be calculated based on the ratio of the noise-removed IR signal and the RD signal, and the gain of the adaptive filter is calculated based on the ratio of the noise-removed IR signal and the RD signal. It is not affected by (gain).

That is, the present invention separates the IR signal and the RD signal included in the received signal based on the ICA, separates the noise signal commonly applied to the separated IR signal and the RD signal, and then uses an adaptive filter to filter these noise signals. By removing the noise signal included in the received signal, the PPG signal from which the noise has been removed can be obtained to accurately measure the user's oxygen saturation value.

The method of the present invention may be applied to a transmission type oxygen saturation measurement apparatus, but is not limited thereto and may also be applied to a reflection type oxygen saturation measurement apparatus according to circumstances. Of course, the method of the present invention can be applied to the ring-shaped oxygen saturation device described with reference to FIGS.

As such, the method according to an embodiment of the present invention measures oxygen saturation based on an independent component analysis (ICA) method, thereby improving the accuracy of an oxygen saturation measurement value.

6 shows a configuration of an apparatus for measuring oxygen saturation based on an independent component analysis technique according to an embodiment of the present invention, and shows a conceptual configuration of an apparatus for performing the methods of FIGS. 4 and 5 . Here, FIG. 6 may be a configuration included in the main body of the device described with reference to FIGS. 1 to 3 .

Referring to FIG. 6 , the apparatus 600 for measuring oxygen saturation according to an embodiment of the present invention includes an acquisition unit 610 , a separation unit 620 , a removal unit 630 , and an operation unit 640 .

The acquisition unit 610 acquires a reception signal including an IR signal and an RD signal that have passed through the user's body.

The separation unit 620 separates the IR signal and the RD signal that have passed through the user's body from the received signal acquired by the acquisition unit 610 .

In this case, the separation unit 620 may separate the IR signal and the RD signal included in the received signal by using the independent component analysis technique (ICA), and the separated IR signal and the RD signal include a noise signal.

That is, the separation unit 620 may separate the IR signal and the RD signal including the common noise signal by using the ICA.

The remover 630 removes noise commonly applied to the separated IR signal and the RD signal.

In this case, the removal unit 630 separates the noise signal commonly applied to the separated IR signal and the RD signal using ICA, and then removes the noise signal commonly applied using an adaptive filter. can do.

The calculator 640 calculates the user's oxygen saturation value by using the noise-removed IR signal and the RD signal.

In this case, the operation unit 640 may obtain a PPG signal by removing noise, and may calculate a user's oxygen saturation value using the obtained PPG signal.

Although the description of the device of FIG. 6 is omitted, each component constituting FIG. 6 may include all the contents described with reference to FIGS. 1 to 5 , which is apparent to those skilled in the art.

The device described above may be implemented as a hardware component, a software component, and/or a combination of the hardware component and the software component. For example, devices and components described in the embodiments may include, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable array (FPA), It may be implemented using one or more general purpose or special purpose computers, such as a programmable logic unit (PLU), microprocessor, or any other device capable of executing and responding to instructions. The processing device may execute an operating system (OS) and one or more software applications running on the operating system. A processing device may also access, store, manipulate, process, and generate data in response to execution of the software. For convenience of understanding, although one processing device is sometimes described as being used, one of ordinary skill in the art will recognize that the processing device includes a plurality of processing elements and/or a plurality of types of processing elements. It can be seen that can include For example, the processing device may include a plurality of processors or one processor and one controller. Other processing configurations are also possible, such as parallel processors.

Software may comprise a computer program, code, instructions, or a combination of one or more thereof, which configures a processing device to operate as desired or is independently or collectively processed You can command the device. The software and/or data may be any kind of machine, component, physical device, virtual equipment, computer storage medium or apparatus, to be interpreted by or to provide instructions or data to the processing device. may be embodied in The software may be distributed over networked computer systems and stored or executed in a distributed manner. Software and data may be stored in one or more computer-readable recording media.

The method according to the embodiment may be implemented in the form of program instructions that can be executed through various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, etc. alone or in combination. The program instructions recorded on the medium may be specially designed and configured for the embodiment, or may be known and available to those skilled in the art of computer software. Examples of the computer-readable recording medium include magnetic media such as hard disks, floppy disks and magnetic tapes, optical media such as CD-ROMs and DVDs, and magnetic such as floppy disks. - includes magneto-optical media, and hardware devices specially configured to store and execute program instructions, such as ROM, RAM, flash memory, and the like. Examples of program instructions include not only machine language codes such as those generated by a compiler, but also high-level language codes that can be executed by a computer using an interpreter or the like.

As described above, although the embodiments have been described with reference to the limited embodiments and drawings, various modifications and variations are possible from the above description by those skilled in the art. For example, the described techniques are performed in an order different from the described method, and/or the described components of the system, structure, apparatus, circuit, etc. are combined or combined in a different form than the described method, or other components Or substituted or substituted by equivalents may achieve an appropriate result.

Therefore, other implementations, other embodiments, and equivalents to the claims are also within the scope of the following claims.

Claims (8)

A method for measuring oxygen saturation, comprising:
obtaining a reception signal including an infrared signal and a red signal that have passed through the user's body;
separating an independent infrared signal and a red signal from the obtained received signal;
removing noise commonly applied to the separated infrared signal and red signal; and
calculating the oxygen saturation value of the user using the infrared signal and the red signal from which the noise has been removed
A method for measuring oxygen saturation comprising a.
According to claim 1,
The separating step
A method for measuring oxygen saturation, characterized in that the independent infrared signal and the red signal are separated from the obtained received signal by using an independent component analysis technique (ICA).
According to claim 1,
The step of removing the noise is
Oxygen saturation measurement, characterized in that after separating the noise signal commonly applied to the separated infrared signal and the red signal using an independent component analysis technique, the separated noise signal is removed using an adaptive filter Way.
According to claim 1,
The step of calculating the oxygen saturation value of the user is
A method for measuring oxygen saturation, characterized in that the noise is removed to obtain a photoplethysmography (PPG) signal, and the oxygen saturation value of the user is calculated using the obtained photoplethysmography signal.
An apparatus for measuring oxygen saturation, comprising:
an acquisition unit for acquiring a reception signal including an infrared signal and a red signal that have passed through the user's body;
a separation unit for separating an independent infrared signal and a red signal from the obtained received signal;
a removal unit for removing noise commonly applied to the separated infrared signal and red signal; and
A calculator that calculates the oxygen saturation value of the user by using the infrared signal and the red signal from which the noise has been removed.
Oxygen saturation measuring device comprising a.
6. The method of claim 5,
the separation part
An apparatus for measuring oxygen saturation, characterized in that the infrared signal and the red signal are separated from the obtained received signal by using an independent component analysis technique (ICA).
6. The method of claim 5,
the removal unit
Oxygen saturation measurement, characterized in that after separating the noise signal commonly applied to the separated infrared signal and the red signal using an independent component analysis technique, the separated noise signal is removed using an adaptive filter Device.
6. The method of claim 5,
the calculation unit
An apparatus for measuring oxygen saturation, characterized in that the noise is removed to obtain a photoplethysmography (PPG) signal, and the oxygen saturation value of the user is calculated using the obtained photoplethysmography signal.

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