KR20230038902A - Method and appararus of detecting heartbeat and breath of human using multichannel radar - Google Patents

Abstract

The present invention relates to a method and an apparatus for detecting a heartbeat and respiration of a person using multichannel radar, which can efficiently identify the position of a person in a specific object in a three-dimensional space by using multichannel radar. According to one embodiment of the present invention, the method for detecting a heartbeat and respiration of a person using multichannel radar, in which an apparatus for detecting a heartbeat and respiration of a person using multichannel radar detects the heartbeat and the respiration of the person, comprises: a step of calculating object energy of a specific area in an entire area of a specific object; a step of calculating a change in the object energy of the specific area in the entire area of the specific object; a step of calculating an accumulated object energy change by accumulating the change in the object energy of each specific area in the entire area of the specific object during a preset time; and a step of detecting a specific area with the largest accumulated object energy change at a preset time in the entire area of the specific object to determine the specific area with the largest accumulated object energy change as an area in which a person is positioned.

Description

Human heartbeat and respiration detection method and apparatus using multi-channel radar

The present invention relates to a method for detecting human heart rate and respiration using multi-channel radar.

In general, biosignals such as heartbeat and respiration are one of the elements that can most conveniently diagnose the health status and presence/absence of abnormalities in the human body. It is very important to check vital signs mainly for critically ill patients, emergency patients, patients during surgery, patients after surgery/treatment/examination/recovery, or elderly people who are vulnerable to maintaining health.

Conventionally, in the case of heart rate and respiration detection radar, phase change using CW (Continuous Wave) radar is extracted or FM (Frequency Modulation) / CW (Continuous Wave) range profile is used to detect a person to the extent of moving to a specific distance. Detected or extracted breathing or heart rate.

However, in recognizing a person in a specific object and detecting heart rate and respiration, information such as angle or height is not known, so it is difficult to limit a specific object and the location of a person by mistaking changes in the surroundings as a person It is difficult to grasp, and because of this, there was a difficult problem in detecting a person's heart rate and respiration.

Republic of Korea Patent Registration No. 10-2236863 (registered on March 31, 2021)

A technical problem to be achieved by the present invention is a method and apparatus for detecting a person's heart rate and respiration using a multi-channel radar that locates a person on a specific object such as a bed and detects a person's heart rate and respiration by using a multi-channel radar. is in providing

Human heart rate and respiration detection method using multi-channel radar according to an embodiment of the present invention, in detecting the heart rate and respiration of the person by a human heart rate and respiration detection device using multi-channel radar, the detection of a specific object Calculating the object energy of a specific area in the entire area, calculating the amount of change in object energy in a specific area in the entire area of a specific object, accumulating the amount of change in object energy for each specific area in the entire area of a specific object for a preset time The step of calculating the amount of change in object energy, the step of detecting a specific area in which the amount of change in cumulative object energy is the largest at a preset point in time among all areas of a specific object and determining it as the person location area.

The amount of change in the object energy is characterized in that it is obtained by taking an absolute value from a difference between the object energy of the n-th area at the current time and the object energy of the n-th area at the previous time.

The cumulative amount of change in object energy is calculated as the sum of the amount of change in object energy in the n-th area at the current time t and the accumulated amount of change in object energy in the n-th area at the previous time t-1.

It is characterized in that if a specific area of the entire area does not detect a cumulative amount of object energy change that exceeds a preset cumulative amount of object energy change at a preset time point, it is determined that the specific object does not have a person location area.

An apparatus for detecting heart rate and respiration of a person using a multi-channel radar according to an embodiment of the present invention calculates the object energy of a specific area in the entire area of a specific object using a radar including at least one antenna, and detects the object energy of the specific object. Calculate the amount of change in object energy of the specific area in the entire area, calculate the amount of change in accumulated object energy by accumulating the amount of change in object energy for each specific area in the entire area of the specific object for a predetermined time period, and a control unit for detecting a specific area having the largest amount of change in the cumulative object energy at a predetermined time point among all areas and determining it as the human location area.

According to the method and apparatus for detecting human heartbeat and respiration using multi-channel radar according to an embodiment of the present invention, the following effects are obtained.

First, the present invention can efficiently locate a person in a specific object in a 3D space using a multi-channel radar.

Second, according to the present invention, a person's heartbeat and respiration can be efficiently grasped at the person's location of a specific object.

Third, the present invention can efficiently obtain object energy, object energy change amount, accumulated object energy change amount, and the like.

1 is a block diagram for explaining an apparatus for detecting human heart rate and respiration using a multi-channel radar according to an embodiment of the present invention.
2 is a flowchart illustrating a method for detecting human heart rate and respiration using a multi-channel radar according to an embodiment of the present invention.
3 is a diagram for explaining an example of detecting an object in an entire area of a specific object in an arbitrary radar according to an embodiment of the present invention.
4 is a diagram for explaining a method of obtaining a distance between specific areas, a vertical angle, and a horizontal angle in an arbitrary radar according to an embodiment of the present invention.
5 shows an example of an object energy map displaying object energy obtained from an entire area of a specific object according to an embodiment of the present invention.
6 illustrates an example of the amount of change in object energy in the entire area of a specific object according to an embodiment of the present invention.

Advantages and features of the present invention, and methods of achieving them, will become clear with reference to the detailed description of the following embodiments taken in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below and can be implemented in various different forms, only these embodiments are intended to complete the disclosure of the present invention, and are common in the art to which the present invention belongs. It is provided to fully inform the knowledgeable person of the scope of the invention, and the invention is only defined by the scope of the claims.

Also, terms used in this specification are for describing the embodiments and are not intended to limit the present invention. In this specification, singular forms also include plural forms unless specifically stated otherwise in a phrase. As used herein, "comprises" and/or "comprising" does not exclude the presence or addition of other components than the recited components. Unless otherwise defined, all terms (including technical and scientific terms) used in this specification may be used in a meaning commonly understood by those of ordinary skill in the art to which the present invention belongs.

Hereinafter, in order to explain the present invention in more detail, embodiments according to the present invention will be described in more detail with reference to the accompanying drawings.

1 is a block diagram for explaining an apparatus for detecting human heart rate and respiration using a multi-channel radar according to an embodiment of the present invention.

Referring to FIG. 1, a human heart rate and respiration detection device (hereinafter referred to as “heart rate and respiration detection device”) using a multi-channel radar according to an embodiment of the present invention includes a memory 10 and a control unit 20. , a display unit 30, an input unit 40, and a radar 50. These components communicate through one or more communication buses or signal lines.

The memory 10 is a part that stores various data.

For example, the memory 10 stores object energy, amount of change in object energy, preset time, cumulative amount of change in object energy, preset point of time, person location area, and the like.

Also, the memory 10 may store heart rate and breathing information of a person.

The controller 20 controls the deep heart rate and respiration detection device according to the present invention. In addition, the control unit 20 is a part that controls each component of the heart rate and respiration detection device.

The control unit 20 calculates the object energy of a specific area in the entire area of a specific object, calculates the amount of change in object energy of the specific area in the entire area of the specific object, and calculates the amount of change in object energy for each specific area in the entire area of the specific object for a predetermined time. The accumulated energy change amount is calculated by accumulating the energy change amount, and a specific area having the greatest amount of accumulated object energy change amount at a preset time is detected among all areas of a specific object, and is controlled to be determined as a human location area.

In addition, the control unit 20 calculates the amount of change in object energy by taking an absolute value from the difference between the object energy of the n-th area at the current time and the object energy of the n-th area at the previous time.

In addition, the controller 20 calculates the accumulated amount of object energy change as the sum of the accumulated amount of change in object energy in the n-th area at the previous time t-1 and the amount of change in object energy in the n-th area at the current time t.

In addition, if the control unit 20 does not detect a cumulative amount of object energy change that exceeds a preset cumulative amount of object energy change at a preset point in time in a specific area out of the entire area, it is determined that the specific object does not have a person location area.

The display unit 30 provides an interface for visual output between the user and the heart rate and respiration detection device.

In addition, the display unit 30 may display an object energy map displaying the object energy obtained from the entire area of a specific object and an accumulated object energy change amount map displaying the accumulated amount of change in object energy obtained from the entire area of the specific object.

The input unit 40 provides an interface for inputting a command signal between the user and the heart rate and respiration detection device. That is, the input unit 40 allows the user to input a command signal, such as an input signal, to the heart rate and respiration detection device, and when the user inputs the user command signal through the input unit 40, the heart rate and respiration detection device can Detects a user command signal of a kind and executes the user's command under the control of the control unit 20 .

The user may input a command signal for changing a preset command, a preset time, or a preset time point to the heart rate and respiration detection device through the input unit 40 .

However, in some embodiments, such as a touch screen, the display unit 30 and the input unit 40 may be integrated or separated.

The radar 50 includes at least one antenna and transmits/receives data using signals such as electromagnetic waves. The radar 50 converts electrical signals into electromagnetic waves and communicates with a communication network and other communication devices through the electromagnetic waves.

According to the present invention, it is possible to detect a person's position (human location area) in a specific object and detect heart rate and respiration by including a multi-channel radar.

For example, the radar 50 transmits and receives signals under the control of the control unit 20 to detect a specific object, determine the location of a person in the specific object (person location area), and detect the heart rate and respiration of the identified person. It is possible.

In addition, the radar 50 may transmit human location area information, heart rate information, respiration information, and the like to an external server, or may receive an entire image file or various types of information from an external server.

2 is a flowchart illustrating a method for detecting human heart rate and respiration using a multi-channel radar according to an embodiment of the present invention.

3 is a diagram for explaining an example of detecting an object in an entire area of a specific object in an arbitrary radar according to an embodiment of the present invention.

4 is a diagram for explaining a method of obtaining a distance between specific areas, a vertical angle, and a horizontal angle in an arbitrary radar according to an embodiment of the present invention.

5 shows an example of an object energy map displaying object energy obtained from an entire area of a specific object according to an embodiment of the present invention.

6 illustrates an example of an accumulated object energy change amount map displaying the accumulated object energy change amount obtained in the entire area of a specific object according to an embodiment of the present invention.

In the following description, it can be explained that the operation of the human heart rate and respiration detection device using multi-channel radar is performed under the control of the control unit 20 included therein.

Referring to FIGS. 2 to 6 , a method for detecting human heart rate and respiration using a multi-channel radar according to an embodiment of the present invention will be described.

The heart rate and respiration detection device calculates the object energy of a specific area in the entire area of the specific object (S201). For example, if the specific object 320 is a couch in which a person lies down and receives treatment, such as a hospital, object energy is calculated in each specific region (or specific position) of the entire area of the couch.

Referring to FIGS. 3 and 4 , the heart rate and respiration detection device calculates the object energy of a specific area in the entire area of the specific object 320 to be described in detail.

Referring to FIG. 3 , in the present invention, n specific areas may be created by dividing the entire area of a specific object 320 into n equal parts.

For example, in order for the heart rate and respiration detection device to calculate the object energy, the specific object 320 is divided into n equal parts, and each specific area (eg, the first area, the second area, ...., the second area) The heart rate and respiration detection device transmits and receives a signal through the radar 310 at a predetermined point (eg, a midpoint of a specific area) of the n area) and calculates object energy.

Here, assuming that the entire area of the specific object 320 is divided into n equal parts, and the preset point of the specific area is the y-axis forward and backward, the left and right x-axis, and the top and bottom z-axis based on the radar 310, x, y, It can be expressed as a z-coordinate. At this time, the x, y, z coordinates can be expressed as distances r, θv, and θh from the zero point to the point P as shown in FIG. 4, and these can be obtained by Equations 1 to 3 below.

As such, the heart rate and respiration detection device may obtain a distance r between the radar 310 and a specific area (or a predetermined point in the specific area), a vertical angle θv, and a horizontal angle θh.

The heart rate and respiration detection device can obtain object energy in a specific area of a specific object using Equation 4 below.

Here, Ri,n corresponds to the received signal corresponding to the distance between the i-th antenna in the signal received at the n-th specific area and the i-th antenna, and corresponds to the radar surface between the 0th reference antenna and the i-th antenna. indicate location. θhn and θvn correspond to vertical and horizontal angles between the nth specific area and the radar 310 . As shown in Equation 4, Sn, which is obtained by processing and summing as many antennas included in the radar 310, when there is a reflected object in the n-th specific area (n-th area), the same phase as in Equation 4 multiplies the antennas, The value increases when it is added, and when there is no reflected object, the value decreases.

Object energy can be obtained in n specific areas in the entire area of the specific object 320, and an object energy map can be drawn by displaying it.

5 shows an example of an object energy map displaying object energy obtained from the entire area of a specific object 320 according to an embodiment of the present invention.

Referring to FIG. 5, when the heart rate and respiration detection device determines a person from a specific object 320, the object energy map means the amount of reflection in a specific area, but a place where the amount of reflection is higher, such as an object made of metal or a mobile phone, Since it shows a larger value, it cannot be determined that there is a person in a place where the value of the amount of reflection is large. Accordingly, the heart rate and respiration detection device must detect the motion of a person through a different processing process.

The heart rate and respiration detection device calculates a change amount of object energy in a specific area in the entire area of the specific object (S202).

The amount of change in object energy in a specific area required for the heart rate and respiration detection device to detect a person's motion can be obtained by Equation 5 below.

Here, S(t)n means the object energy of the n-th specific area (n-th area) from the current time, and S(t-1)n is the object energy of the n-th specific area (n-th area) from the previous time. means The change in object energy Sdiffn is the difference between the object energy S(t)n of the nth specific area (nth area) at the current time and the object energy S(t-1)n of the nth specific area (nth area) from the previous time. It can be obtained by taking the absolute value.

For example, in the present invention, the previous time may use a value within 0.1 second based on the current time. This is because the heart rate and respiration detection device is easy to detect a person's respiration and heart rate. However, the present invention can set the previous time to various values and is applicable.

Since Sdiffn, the amount of change in object energy, shows the instantaneous amount of change in object energy, it is not enough to use this to limit the position of a person in a specific object 320, and the value of the amount of change in object energy is accumulated in each n-th specific area (n-th area). Therefore, it is necessary to obtain the maximum change in body energy.

The heart rate and respiration detection device calculates the accumulated object energy change by accumulating the object energy change for each specific area in the entire area of the specific object for a predetermined time (S203). Here, the preset time can be set by the user, and various embodiments are possible.

The heart rate and respiration detection device accumulates the object energy change for each specific area in the entire area of the specific object 320 for a predetermined time, and the maximum change in object energy can be obtained by Equation 6 below.

Here, Ssum(t)n is the accumulated object energy change in the nth specific area (nth area) at the current time t, and Ssum(t-1)n is the nth specific area (nth area) at the previous time t-1 ), and Sdiff(t)n is the change in object energy of the nth specific area (nth area) at the current time t.

The heart rate and respiration detection device detects a specific region in which the cumulative object energy change amount is the largest at a predetermined time point among all regions of the specific object and determines it as the human location region (S204). At this time, the person location area is an area indicating a location where a person exists in a specific object 320 .

For example, if the preset time point is 8 seconds, the heart rate and respiration detection device detects the 9th area and sets the 9th area as the human position area if the nth area with the greatest change in accumulated object energy up to 8 seconds is the 9th area. to decide

Here, the heart rate and respiration detection device determines that the specific object 320 does not have a person position area when it does not detect a cumulative amount of object energy change that exceeds a preset cumulative object energy change amount at a preset time in a specific area out of the entire area. .

It is possible to obtain the cumulative amount of change in object energy in n specific areas of the entire area of the specific object 320, and display it to draw a map of the amount of cumulative amount of change in object energy.

FIG. 6 shows an example of an accumulated object energy change amount map displaying the accumulated object energy change amount obtained in the entire area of a specific object 320 according to an embodiment of the present invention.

Referring to FIG. 6 , the heart rate and respiration detection apparatus determines a specific region in the middle of which the cumulative object energy change amount is the largest as the human position region.

The heart rate and respiration detection device detects the human heart rate and respiration by using the amount of change in object energy in the human location area (S205).

The heart rate and respiration detection device continuously checks the human location area and detects the human respiration and heart rate using Sdiffn, the amount of change in object energy.

For example, since the respiration frequency of an adult male is approximately 0.1 Hz to 0.4 Hz and the heart rate is approximately 1 Hz to 2 Hz, respiration and heart rate components are filtered out through frequency filtering. There are several methods for frequency filtering, and there is also a method of frequency filtering by taking a value of a specific index by using an FIR band pass filter or performing FFT (Fast Fourier Transform) on data accumulated for a certain period of time. The heart rate and respiration detection device according to the present invention calculates the heart rate BPM and respiration BPM by measuring the time when the obtained heart rate and respiration signal jumps over a certain boundary value, goes down again, and then jumps over a certain boundary value again. Detect heart rate and respiration.

The method according to the embodiment of the present invention may be implemented in the form of program instructions that can be executed through various computer means and recorded on a computer readable recording medium. A computer-readable recording medium may include program instructions, data files, data structures, etc. alone or in combination. The programs (program instructions) recorded on the recording medium may be those specially designed and configured for the present invention or those known and usable to those skilled in computer software. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks and magnetic tapes, optical media such as CDROMs and DVDs, and magnetic-optical media such as floptical disks. Hardware devices specially configured to store and execute program instructions, such as magneto-optical media, ROM, RAM, flash memory, etc., are included. Examples of program instructions include high-level language codes that can be executed by a computer using an interpreter, as well as machine language codes such as those produced by a compiler. The hardware devices described above may be configured to act as one or more software modules to perform the operations of the present invention, and vice versa.

As described above, the present invention has been described with reference to the embodiments shown in the drawings, but this is only for explaining the present invention, and those skilled in the art to which the present invention belongs may make various modifications or equivalents from the detailed description of the present invention. It will be appreciated that one embodiment is possible. Therefore, the true scope of the present invention should be determined by the technical spirit of the claims.

10: memory
20: control unit
30: display unit
40: input unit
50: radar

Claims (5)

In detecting the heartbeat and respiration of a person by a human heartbeat and respiration detection device using a multi-channel radar,
Calculating the object energy of a specific area in the entire area of a specific object;
Calculating a change amount of object energy of the specific area in the entire area of the specific object;
calculating a cumulative amount of change in object energy by accumulating the amount of change in object energy for each specific area in the entire area of the specific object for a predetermined period of time;
A human heartbeat and respiration detection method using a multi-channel radar comprising the step of detecting a specific region with the greatest change in cumulative object energy at a predetermined time point among the entire regions of the specific object and determining it as the human location region. According to claim 1,
The change in body energy is
Human heartbeat and respiration detection method using multi-channel radar, characterized in that the absolute value is obtained from the difference between the object energy in the n-th area at the current time and the object energy in the n-th area at a previous time. According to claim 1,
The accumulated object energy change amount is calculated as the sum of the cumulative object energy change amount in the n-th area at the previous time t-1 and the object energy change amount in the n-th area at the current time t. Person using multi-channel radar, characterized in that heart rate and respiration detection method. According to claim 1,
and determining that the person location area does not exist in the specific object, when the specific area out of the entire area does not detect the cumulative amount of change in object energy that exceeds the preset accumulated amount of change in object energy at the preset time point. Human heart rate and respiration detection method using channel radar. a radar comprising at least one antenna;
Calculate the object energy of the specific area in the entire area of the specific object, calculate the amount of change in the object energy of the specific area in the entire area of the specific object, and calculate the amount of change in the object energy of the specific area in the entire area of the specific object for a predetermined time. A control unit configured to calculate a cumulative amount of change in object energy by accumulating the amount of change in object energy, and to detect a specific area in which the amount of accumulated object energy change is the largest at a predetermined time among the entire areas of the specific object, and determine the area as a person location area. A device for detecting human heart rate and respiration using multi-channel radar.

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