JP6932090B2 - Monitoring device - Google Patents

Description

The present disclosure relates to a monitoring device for monitoring a subject on bedding.

In recent years, with the progress of an aging society, the number of elderly people living alone or households with only elderly couples is increasing. In addition, due to depopulation, it is no longer possible to expect watching over by neighboring people, and there is a limit to the support provided by caregivers who support their lives, so it is often not possible to sufficiently confirm the safety of the elderly and those living alone. .. Therefore, there are frequent delays in responding to unforeseen circumstances. Therefore, in order to prevent such a situation from occurring, a system for monitoring a subject using a microwave Doppler sensor is known.

For example, Japanese Patent Application Laid-Open No. 2012-75861 (Patent Document 1) discloses a safety monitoring device that collects biological information of a subject and monitors the safety of the subject. The safety monitoring device irradiates the subject with microwaves, detects the subject's body movements and respiration from the Doppler-shifted reflected waves, and examines the subject's body movements and respiration rate within a predetermined time. Monitor the safety of the person.

Japanese Unexamined Patent Publication No. 2012-75861

In the technique according to Patent Document 1, the body movement rate and the respiratory rate are calculated using the microwave Doppler shift signal output by the microwave Doppler sensor, and the safety of the subject is monitored using the safety pattern that is a combination of these. do.

For example, specific examples of accidents include wandering and falls that may occur when an elderly person in need of care leaves the bed without the caregiver noticing. In order to suppress the occurrence of such an accident, it is necessary to detect an action related to getting up when the subject gets out of bed such as a bed. However, in Patent Document 1, since the movement of the subject cannot be detected, the occurrence of the accident cannot be suppressed.

It is an object of the present disclosure to provide a monitoring device capable of ensuring the safety of a subject by appropriately detecting the rising motion of the subject in a certain aspect.

According to certain embodiments, a monitoring device for monitoring the subject on the bedding is provided. The monitoring device includes a receiving unit that receives the reflected wave of the microwave irradiated to the subject, a signal generating unit that generates an I-channel signal and a Q-channel signal that are orthogonal to each other from the reflected wave signal, and an I-channel signal. And a detection unit that detects the movement of the subject at predetermined time intervals based on the Q channel signal. The subject's movements include at least one of the subject's approaching and leaving movements with respect to the monitoring device. A determination unit that determines whether or not the subject has risen based on the number of approaching movements and the number of separation movements during the duration of the subject's movement, and when the subject has risen. , It is equipped with an output control unit that outputs warning information.

According to the present disclosure, it is possible to ensure the safety of the subject by appropriately detecting the rising motion of the subject.

It is a figure which shows the whole structure of the monitoring system according to Embodiment 1. FIG. It is a top view which shows the structure of the plane antenna in the monitoring apparatus according to Embodiment 1. FIG. It is a figure which shows the directivity characteristic of the plane antenna according to Embodiment 1. FIG. It is a figure for demonstrating the installation method of the monitoring apparatus according to Embodiment 1. FIG. It is a block diagram for demonstrating the detailed structure of the control circuit according to Embodiment 1. FIG. It is a block diagram for demonstrating the detailed structure of the analog signal processing circuit according to Embodiment 1. FIG. It is a figure which shows an example of the IQ plane of the reflected wave according to Embodiment 1. FIG. It is a figure which shows the approaching motion, the detaching motion, and the time change of the body movement amplitude according to the first embodiment. It is a figure which shows the experimental result according to Embodiment 1. FIG. It is a figure which shows the state estimation example of the subject according to this Embodiment 1. It is a figure which shows an example of the processing procedure of the monitoring apparatus according to Embodiment 1. FIG. It is a figure for demonstrating the installation method of the monitoring apparatus according to Embodiment 2. It is a figure for demonstrating the installation method of the monitoring apparatus according to Embodiment 3. It is a figure for demonstrating the installation method of the monitoring apparatus according to Embodiment 3. It is a figure which shows the approaching motion, the detaching motion, and the time change of the body movement amplitude according to the third embodiment. It is a figure which shows the experimental result according to Embodiment 3. It is a figure which shows the experimental result at the time of the rising operation according to Embodiment 4. It is a figure which shows the experimental result at the time of turning over according to Embodiment 4. It is a figure which shows the other experimental result at the time of the rising operation according to Embodiment 4. It is a figure which shows the other experimental result at the time of turning over according to Embodiment 4. It is a figure for demonstrating the installation method of the monitoring apparatus according to Embodiment 5. It is a figure which shows the experimental result at the time of the rising operation according to Embodiment 5. It is a figure which shows the experimental result at the time of turning over according to Embodiment 5. It is a figure which shows the other experimental result at the time of the rising operation according to Embodiment 5. It is a figure which shows the other experimental result at the time of turning over according to Embodiment 5. It is a figure for demonstrating the modification of the installation method of the monitoring apparatus according to Embodiment 5. It is a figure which shows the waveform of the body motion signal detected by the microwave Doppler sensor.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are designated by the same reference numerals. Their names and functions are the same. Therefore, the detailed description of them will not be repeated.

[Embodiment 1]
<Overall system configuration>
FIG. 1 is a diagram showing an overall configuration of a monitoring system 1000 according to the first embodiment. With reference to FIG. 1, the monitoring system 1000 includes a monitoring device 100 for monitoring a subject and a terminal device 200. The terminal device 200 is a terminal on the side of watching over a subject who is a monitoring (watching) target person, and is, for example, a smartphone. However, the terminal device 200 may be another device such as a foldable mobile phone, a tablet terminal device, a PC (personal computer), or the like.

The network 55 for connecting the monitoring device 100 and the terminal device 200 to each other includes various networks such as the Internet and a mobile terminal communication network. The network 55 is not limited to this, and a wired communication method may be adopted, or another wireless communication method such as a wireless LAN (local area network) may be adopted.

The monitoring device 100 includes a control circuit 152, a memory 154, a speaker 156, a communication interface 158, and a microwave Doppler sensor 160 as main components. The monitoring device 100 may include a display for displaying various information and an input device such as a button for receiving various inputs from the user.

The control circuit 152 typically includes a microprocessor including a CPU and the like, an analog signal processing circuit for processing an analog signal from the microwave Doppler sensor 160, and an AD converter. The detailed configuration of the control circuit 152 will be described later. The microprocessor reads and executes the program stored in the memory 154, and functions as a control unit that controls the operation of each unit of the monitoring device 100. For example, the microprocessor realizes the processing of the control circuit 152, which will be described later, by executing the program.

The memory 154 is realized by a RAM (Random Access Memory), a ROM (Read-Only Memory), or the like. The memory 154 stores a program executed by the microprocessor, data used by the microprocessor, and the like.

The speaker 156 converts the audio signal given from the microprocessor into audio and outputs it to the outside of the monitoring device 100. The communication interface 158 encodes the communication data from the microprocessor, converts it into a communication signal, and transmits the communication signal to the terminal device 200. Further, the received signal is decoded from the terminal device 200, converted into communication data, and output to the microprocessor. The communication method may be a wireless communication method using a wireless LAN or the like, or a wired communication method using USB (Universal Serial Bus) or the like.

The microwave Doppler sensor 160 radiates microwaves to the subject, and outputs a signal reflecting the movement of the subject's body or the like from the reflected microwaves to the control circuit 152. Further, the microwave Doppler sensor 160 generates an I-channel signal and a Q-channel signal orthogonal to each other from the input reflected wave (reflected signal).

Specifically, the microwave Doppler sensor 160 includes an oscillation circuit 21, amplifiers 22A and 22B, a transmitting antenna 25, a receiving antenna 30, mixers 32I and 32Q, low-pass filters (LPF) 33I and 33Q, and 90. Includes a degree shifter 38. The transmitting antenna 25 and the receiving antenna 30 are composed of a flat antenna. The transmitting antenna 25 and the receiving antenna 30 may be composed of a waveguide antenna or a dielectric antenna.

The microwave sine wave signal output from the oscillation circuit 21 is amplified by the amplifier 22A and radiated from the transmitting antenna 25. The microwave Mt radiated into the space is reflected on the body surface (for example, the chest) of the subject, which is the object. The reflected microwave Mr of the radiated microwave has a Doppler shift corresponding to the body movement (body movement) of the subject and the respiratory movement and the heartbeat movement. Therefore, the signal (reflected signal) of the reflected wave Mr input to the receiving antenna 30 becomes a signal corresponding to the body movement, the respiratory movement, and the heartbeat movement of the subject.

The reflected signal received by the receiving antenna 30 is amplified by the amplifier 22B. The amplified signal Dr is input to the mixer 32I on the I channel side and the mixer 32Q on the Q channel side. Here, the signal Dr input to the I channel side is referred to as "Dri" for convenience, and the signal Dr input to the Q channel side is referred to as "Drq" for convenience.

The signal Dt amplified by the amplifier 22A is input to the mixer 32I on the I channel side and the mixer 32Q via the 90-degree phase shifter 38. Here, the signal Dt input to the I channel side is referred to as "Dti" for convenience, and the signal Dt input to the Q channel side is referred to as "Dtq" for convenience. In the present embodiment, a configuration in which the phase of the signal Dtq with respect to the signal Dti is shifted by 90 degrees by using the 90-degree phase shifter 38 will be described, but the configuration is not limited to this configuration. For example, by using the 90-degree phase shifter 38 on the input side of the mixer 32Q, the phase of the signal Drq with respect to the signal Dr may be shifted by 90 degrees.

The signal frequency-converted (down-converted) by the mixer 32I is input to the LPF33I. The LPF33I outputs a signal obtained by removing a relatively high frequency component from the signal to the control circuit 152 as a baseband signal Dbi on the I channel side. Further, the frequency-converted signal by the mixer 32Q is input to the LPF33Q. The LPF33Q outputs a signal obtained by removing a relatively high frequency component from the signal to the control circuit 152 as a baseband signal Dbq on the Q channel side. The baseband signals Dbi and Dbq are output as microwave Doppler shift signals that have undergone Doppler shift due to the body movement of the subject, respectively.

The velocity and amplitude of the reflected signal input to the receiving antenna 30 change with time. Therefore, although the I-channel side signal and the Q-channel side signal are instantaneously 90 degrees out of phase, the phase advance of the baseband signal Dbq with respect to the baseband signal Dbi depends on the speed and direction of the signal. The one is not constant and always fluctuates with time.

FIG. 2 is a plan view showing a configuration of a flat antenna in the monitoring device 100 according to the first embodiment. FIG. 3 is a diagram showing the directivity characteristics of the planar antenna according to the first embodiment. Specifically, FIG. 3A is a diagram showing a directivity characteristic (pattern) in the azimuth (horizontal) direction, and FIG. 3B is a diagram showing a directivity pattern in the elevation angle (vertical) direction. be.

With reference to FIG. 2, the planar antenna in the monitoring device 100 includes a transmitting antenna 25 and a receiving antenna 30. Each of the transmitting antenna 25 and the receiving antenna 30 has eight antenna elements.

With reference to FIG. 3, the directional pattern of the planar antenna has a main lobe and two side lobes for each of the azimuth and elevation directions. For example, the radiation angle 123A, which is the 3 dB beam width (half width) of the main lobe in the azimuth direction, is ± 20 degrees, and the radiation angle 123B, which is the half width of the main lobe in the elevation angle direction, is ± 15 degrees. The angles of the radiation angles 123A and 123B are not limited to the above angles.

<Installation method of monitoring device>
The installation method of the monitoring device 100 for monitoring the subject lying on the bedding will be described. Hereinafter, the configuration in which the bedding is a bed will be described, but the bedding is not limited to this, and the bedding may be a futon or the like.

FIG. 4 is a diagram for explaining an installation method of the monitoring device 100 according to the first embodiment. Specifically, FIG. 4A is a schematic view of the subject on the bed when viewed from the side. FIG. 4B is a schematic view of the subject on the bed when viewed from above.

The monitoring device 100 is attached near the bottom 252 of the main body 251 of the bed 250 (see FIG. 4A). For example, the monitoring device 100 is fixed at a distance L = 1 cm to 20 cm from the bottom 252 by a fixing metal fitting or the like. Further, the monitoring device 100 may be installed between the bottom portion 252 and the mattress 253, or may be inserted inside the mattress 253. The monitoring device 100 may be directly fixed to the bottom portion 252. For example, in the case of a reclining bed, it is attached to the inside or bottom of the mattress of the reclining section, or to a table that holds the mattress to be reclined.

When viewed in a plan view, the monitoring device 100 is attached near the chest (or epigastrium) of the subject lying (lying) on the mattress 253 (see FIG. 4 (b)). Further, the monitoring device 100 is provided on the center line 181 in the left-right direction of the bed 250.

Even when the subject gets up, the monitoring device so that the subject is on the peak direction line 111a (virtual line) of the main lobe in the elevation angle direction of the flat antenna (see FIG. 4A). The 100 is arranged at an angle θa (for example, 20 to 60 degrees) from the horizontal. As a result, the movement of the subject can be detected not only when the subject is lying down but also when he / she gets up.

When the subject is a caregiver or the like who needs to be watched over, the direction of getting off the bed 250 is often limited to either the left-right direction. For example, the bed 250 is arranged so that the bed end 185 is in the vicinity of a wall, a window, or the like so that the bed end 185 cannot be physically descended from the bed end 185 side. The bedside guard may be provided at the bed end 185. In the example of FIG. 4, a bedside guard 180a is provided on a part of the bed end 180, and the subject is guided to get off the bed 250 from the exit 180b.

Here, the monitoring device 100 can detect whether the subject is approaching or distant from the monitoring device 100 at predetermined intervals by using the I-channel signal and the Q-channel signal of the reflected wave Mr. It is configured in.

In the example of FIG. 4, when the subject gets up from the bed 250, the subject is present on the peak direction line 111a, and the subject moves away from the monitoring device 100 (that is, the separation motion). Is doing. On the other hand, when the subject lies on the bed 250, the subject is present on the peak direction line 111a and the subject approaches the monitoring device 100 (hereinafter, also referred to as “approaching motion”). .) Is being performed.

When the subject is a caregiver, both approaching and separating movements are detected because he / she gets up with his / her hand or holds the bedside handrail. Therefore, when the monitoring device 100 determines that the subject's approaching motion is greater than the approaching motion, the monitoring device 100 determines that the subject has risen, and determines that the subject's approaching motion is greater than the approaching motion. It is determined that the subject has been bedridden. In this way, the monitoring device 100 can monitor whether the subject has risen or laid down by using the I-channel signal and the Q-channel signal.

In the above, the configuration in which the monitoring device 100 is provided near the bottom 252 of the bed 250 has been described, but the configuration is not limited to this configuration. When the subject is on the peak direction line 111a when the subject is lying on the bed 250 and when the subject is awake, and when the subject is awakened from the bed 250, the subject is monitored at a position away from the monitoring device 100. It suffices if the device 100 is provided.

<Control circuit configuration>
FIG. 5 is a block diagram for explaining a detailed configuration of a control circuit according to the first embodiment. With reference to FIG. 5, the control circuit 152 includes an analog signal processing circuit 41, an AD converter 43, and a microprocessor 45. Typically, the microprocessor 45 is a digital signal processor (DSP) or a microcontroller unit (MCU) specialized in digital signal processing. Instead of the AD converter 43, the AD conversion function in the microprocessor 45 may be used.

The analog signal processing circuit 41 removes unnecessary frequency band components from the signal input from the microwave Doppler sensor 160 and outputs the signal to the AD converter 43. Specifically, the analog signal processing circuit 41 outputs the I-channel analog signal Shi and the Q-channel analog signal Shq in the heartbeat component band (0.7 Hz to 20 Hz), and outputs the body movement component band (0.3 Hz). ~ 90Hz) I-channel analog signal Sti and Q-channel analog signal Stq are output. The band of the body movement component also includes the band of the heartbeat component.

FIG. 6 is a block diagram for explaining a detailed configuration of the analog signal processing circuit 41 according to the first embodiment. With reference to FIG. 6, the analog signal processing circuit 41 includes a baseband signal Dbi on the I channel side output from the microwave Doppler sensor 160 and a baseband signal Dbq on the Q channel side output from the microwave Doppler sensor 160. Accepts the input. The baseband signal Dbi is distributed to the analog signals Dbia and Dbib. The baseband signal Dbq is distributed to the analog signals Dbqa and Dbqb.

The analog signal processing circuit 41 includes signal processing circuits 149A to 149D. The analog signal Dbia is output to the signal processing circuit 149A for heart rate measurement. The signal processing circuit 149A includes a high-pass filter HPF143A, a low-pass filter LFP144A, and an amplifier 145A.

HPF143A removes the low frequency components of the analog signal Dbia. As an example, HPF143A removes signal components below 0.7 Hz. The removed signal is output to the LFP144A. The LFP144A removes the high frequency component of the analog signal Dbia output from the HPF143A. As an example, LFP144A removes signal components above 20 Hz. The removed signal is output to the amplifier 145A. The amplifier 145A amplifies the analog signal Dbia output from the LFP144A by a predetermined time (for example, 400 times) to generate the analog signal Shi. The analog signal Shi is output to the AD converter 43 (see FIG. 5).

The analog signal Dbib is output to the signal processing circuit 149B for respiration measurement. The signal processing circuit 149B includes an HPF 143B, an LFP 144B, and an amplifier 145B.

HPF143B removes the low frequency components of the analog signal Dbib. As an example, HPF143B slowly removes signal components below 0.3 Hz. As an example, at 0.3 Hz, the cut-off voltage amplitude is attenuated by 6 dB, and at 0.1 Hz, the attenuation is about 10 dB. This facilitates the DC offset process, and makes it possible to return the body motion signal to the zero line and extract the respiratory component at a higher speed. The removed signal is output to the LFP144B. The LFP144B removes the high frequency component of the analog signal Dbib output from the HPF143B. As an example, LFP144B removes signal components above 90 Hz. The removed signal is output to the amplifier 145B. The amplifier 145B amplifies the analog signal Dbib output from the LFP144B by a predetermined time (for example, 100 times) to generate the analog signal Sti. The analog signal Sti is output to the AD converter 43 (see FIG. 5).

Since the amplitude of the heartbeat signal is about 1/10 or less of the amplitude of the respiration signal, the amplification factor of the heartbeat measurement amplifier 145A is larger than the amplification factor of the respiration measurement amplifier 145B. 145A and 145B are designed. As an example, the amplification factor of the amplifier 145A is 400 times, and the amplification factor of the amplifier 145B is 100 times.

The analog signal Dbqa is output to the signal processing circuit 149C for heart rate measurement. The signal processing circuit 149C includes an HPF 143C, an LFP 144C, and an amplifier 145C.

HPF143C removes the low frequency component of the analog signal Dbqa. As an example, HPF143C removes signal components below 0.7 Hz. The removed signal is output to the LFP144C. The LFP144C removes the high frequency component of the analog signal Dbqa output from the HPF143C. As an example, LFP144C removes signal components above 20 Hz. The removed signal is output to the amplifier 145C. The amplifier 145C amplifies the analog signal Dbqa output from the LFP144C by a predetermined time (for example, 400 times) to generate the analog signal Shq. The analog signal Shq is output to the AD converter 43 (see FIG. 5).

The analog signal Dbqb is output to the signal processing circuit 149D for respiration measurement. The signal processing circuit 149D includes an HPF143D, an LFP144D, and an amplifier 145D.

HPF143D removes the low frequency component of the analog signal Dbqb. As an example, HPF143D removes signal components below 0.3 Hz. As an example, at 0.3 Hz, the cut-off voltage amplitude is attenuated by 6 dB, and at 0.1 Hz, the attenuation is about 10 dB. This facilitates the DC offset process, and makes it possible to return the body motion signal to the zero line and extract the respiratory component at a higher speed. The removed signal is output to the LFP144D. The LFP144D removes the high frequency component of the analog signal Dbqb output from the HPF143D. As an example, LFP144D removes signal components above 90 Hz. The removed signal is output to the amplifier 145D. The amplifier 145D amplifies the analog signal Dbqb output from the LFP 144D by a predetermined time (for example, 100 times) to generate the analog signal Stq. The analog signal Stq is output to the AD converter 43 (see FIG. 5).

Since the amplitude of the heartbeat signal is about 1/10 or less of the amplitude of the respiration signal, the amplification factor of the heartbeat measurement amplifier 145C is larger than the amplification factor of the respiration measurement amplifier 145D. Amplitudes 145C and 145D are designed. As an example, the amplification factor of the amplifier 145C is 400 times, and the amplification factor of the amplifier 145D is 100 times.

HPF143A to 143D and LFP144A to 144D are, for example, active filters using operational amplifiers. Alternatively, HPF 143A to 143D may be passive elements using coils, capacitors, and resistors.

As described above, by performing band limitation and amplification independently for heart rate measurement and respiration measurement, a high-quality analog signal having a high SN (Signal Noise) ratio is extracted in the heart rate range and the respiration range. LFP144A to 144D also function as an antialiasing filter for the AD converter 43. In the present embodiment, the sampling frequency is 400 Hz, and LPF144A to LPF144D detect a heartbeat component and a faster body movement component. The cutoff frequency of LPF144A and LPF144C is 20 Hz, which is 1/2 (200 Hz) or less of the sampling frequency, and the antialiasing component is removed. The cutoff frequency of LPF144C and LPF144D is 90 Hz, which is 1/2 (200 Hz) or less of the sampling frequency, and the antialiasing component is removed.

Again, referring to FIG. 5, the AD converter 43 performs 16-bit (or 12-bit) AD conversion of the input signal. Specifically, the AD converter 43 receives the inputs of the analog signals Shi, Shq, Ti, Stq, and at a predetermined sampling rate (for example, frequency 400 Hz, period 2.5 ms), the analog signals Shi, Shq, The Sti and Stq are converted into digital signals and output to the microprocessor 45. The digital signals Shi, Shq, Ti, and Stq are appropriately offset-adjusted as ± signals according to the voltage amplitude.

The microprocessor 45 executes various processes using each digital signal Shi, Shq, Ti, Stq. Specifically, the microprocessor 45 includes an operation monitoring unit 50, a state estimation unit 52, an output control unit 54, a heart rate calculation unit 60, and a respiration calculation unit 70 as main functional configurations. The HPF64I, 64Q, 82I, 82Q and LPF65I, 65Q are digital filters realized by digital signal processing.

The heart rate calculation unit 60 receives the inputs of the digital signals Shi and Shq and executes various processes. Specifically, the heart rate calculation unit 60 includes HPF64I on the I-channel side, HPF64Q on the Q-channel side, LPF65I on the I-channel side, LPF65Q on the Q-channel side, and a fundamental wave detection unit 66I on the I-channel side. It includes a fundamental wave detection unit 66Q on the Q channel side and a heart rate averaging processing unit 67.

The HPF64I and 64Q generate digital signals Hai and Haq by removing the low frequency components (particularly, the band of the respiratory component) of the digital signals Shi and Shq, respectively. The HPF64I outputs the digital signal Hai to the LPF65I, and the HPF64Q outputs the digital signal Haq to the LPF65Q. Typically, HPF64I, 64Q removes frequency components below 0.7 Hz (ie, equivalent to 42 bpm).

The LPF65I and 65Q generate the digital signals Hbi and Hbq by removing the high frequency components of the digital signals Hai and Haq, respectively. The LPF65I outputs the digital signal Hbi to the fundamental wave detection unit 66I, and the LPF65Q outputs the digital signal Hbq to the fundamental wave detection unit 66Q. Typically, LPF65I, 65Q removes frequency components above 20 Hz. The LPF65I and 65Q may be configured to remove frequency components of 4 Hz (that is, corresponding to 240 bpm) or higher.

The fundamental wave detection units 66I and 66Q calculate the heart rate using the digital signals Hbi and Hbq, respectively. Specifically, the fundamental wave detection unit 66I performs a fast Fourier transform (FFT) on the digital signal Hbi accumulated for a predetermined time (for example, 5 seconds), decomposes it into individual signal components, and then decomposes each component into individual signal components. Is performed on the frequency spectrum to create frequency distribution data. The fundamental wave detection unit 66I selects a frequency distribution (for example, 0.7 Hz to 4 Hz) in a predetermined range related to the heartbeat from the frequency distribution data, and selects the frequency component having the highest intensity (peak) from the frequency distribution as the fundamental wave. Detect as data. The fundamental wave detection units 66I and 66Q may detect the fundamental wave data by using an autocorrelation function, a wavelet transform, or the like.

The fundamental wave detection unit 66I calculates the heart rate Hi, which is the number of heartbeats per unit time (that is, one minute), by multiplying the fundamental wave data by 60. Similarly, the fundamental wave detection unit 66Q calculates the heart rate Hq using the digital signal Hbq.

The heart rate averaging processing unit 67 averages the heart rate Hi and the heart rate Hq to calculate the heart rate Hn. The heart rate averaging processing unit 67 may integrate digital signals Hbi and Hbq and appropriately set a threshold value to remove a signal having a low noise level intensity or a signal having poor periodicity.

The respiration calculation unit 70 receives the inputs of the digital signals Sti and Stq and executes various processes. Specifically, the respiration calculation unit 70 includes the LPF71I on the I channel side, the LPF71Q on the Q channel side, the fundamental wave detection unit 72I on the I channel side, the fundamental wave detection unit 72Q on the Q channel side, and the respiratory averaging process. Including part 73.

The LPF71I and 71Q generate digital signals Bai and Baq by removing high frequency components of the digital signals Sti and Stq, respectively. The LPF71I outputs the digital signal Bai to the fundamental wave detection unit 72I, and the LPF71Q outputs the digital signal Baq to the fundamental wave detection unit 72Q. Typically, LPF71I, 71Q removes frequency components above 0.75 Hz (ie, corresponding to 45 bpm).

The fundamental wave detection units 72I and 72Q calculate the respiratory rate using the digital signals Bai and Baq, respectively. The fundamental wave detection unit 72I calculates the respiratory rate by the same calculation method as the calculation method by the fundamental wave detection unit 66I. Specifically, the fundamental wave detection unit 72I creates frequency distribution data by performing a fast Fourier transform on the digital signal Bai accumulated for a predetermined time (for example, 10 seconds). The fundamental wave detection unit 72I detects the frequency component having the highest intensity from the frequency distribution (for example, 0 Hz to 0.75 Hz) in a predetermined range related to respiration among the frequency distribution data as the fundamental wave data. The fundamental wave detection unit 72I calculates the respiratory rate Bi, which is the number of respirations per unit time (that is, one minute), by multiplying the fundamental wave data by 60. Similarly, the fundamental wave detection unit 72Q calculates the respiratory rate Bq using the digital signal Baq.

The respiratory averaging processing unit 73 calculates the respiratory rate Bn by averaging the respiratory rate Bi and the respiratory rate Bq. The respiratory averaging processing unit 73 may integrate digital signals Bai and Baq and appropriately set a threshold value to remove a signal having a low noise level intensity or a signal having poor periodicity.

The HPF82I and 82Q generate digital signals Cti and Ctq by removing low-frequency components of the digital signals Sti and Stq, respectively (that is, filtering processing). The HPF82I outputs the digital signal Cti to the operation monitoring unit 50, and the HPF82Q outputs the digital signal Ctq to the operation monitoring unit 50. The HPF82I and 82Q have a cutoff frequency of about 0.7 Hz to 3 Hz, and remove frequency components below the frequency. In the present embodiment, for example, HPF82I, 82Q removes frequency components of 2 Hz or less.

As a result, the digital signals Cti and Ctq from which noise components such as the vertical movement of the body due to the sinking of the body during the rising motion, the lying motion, the rolling motion, and the unnecessary movement of the mattress 253 due to the rotation are removed are used as the motion monitoring unit. It is input to 50. Therefore, the influence of the amplitude offset of the digital signals Cti and Ctq can be removed, and the accuracy of the operation determination by the operation monitoring unit 50 can be improved.

The motion monitoring unit 50 monitors the motion of the subject on the bedding based on the reflected wave signal (specifically, each digital signal Cti, Ctq). Specifically, the motion monitoring unit 50 includes a body motion calculation unit 56, a detection unit 57, and a determination unit 58.

The detection unit 57 approaches the subject at predetermined intervals based on the digital signal Cti (hereinafter, also referred to as “I signal Cti”) and the digital signal Ctq (hereinafter, also referred to as “Q signal Ctq”). Detects motion and separation motion. Specifically, the detection unit 57 detects the approaching motion and the separating motion based on the trajectories of the I signal Cti and the Q signal Ctq on the IQ plane.

FIG. 7 is a diagram showing an example of the IQ plane of the reflected wave. The IQ plane, which is a complex plane, is composed of an I axis (in-phase axis), which is a horizontal axis, and a Q axis (quadrature phase axis), which is a vertical axis. FIG. 7A shows a case where the subject approaches the monitoring device 100, and FIG. 7B shows a case where the subject separates from the monitoring device 100. Each point in FIG. 7 (a) and each point in FIG. 7 (b) are plots of the I signal Cti and the Q signal Ctq for each sampling time.

With reference to FIG. 7A, the counterclockwise arrow 601 indicates the direction of the locus of the coordinates of the I signal Cti and the Q signal Ctq on the IQ plane when the subject approaches the monitoring device 100. ing. With reference to FIG. 7B, the clockwise arrow 602 indicates the direction of the trajectory of the coordinates on the IQ plane when the subject separates from the monitoring device 100.

The detection unit 57 calculates the locus direction for each point. Specifically, the detection unit 57 calculates the phase θ of the reflected wave on the IQ plane for each sampling time. The phase θ is calculated by arctan (Q signal Ctq / I signal Cti). The detection unit 57 determines whether the phase θ at each point is increasing (that is, in the increasing direction) or is the phase θ decreasing (that is, in the decreasing direction), and calculates the locus direction. ..

For example, the detection unit 57 calculates the increasing direction and the decreasing direction of the phase θ 40 times (that is, once every 2.5 milliseconds) in a unit period (for example, 0.1 second), and approaches each time. Determine either separation or undetermined. Here, when the amplitude of the body motion signal (I signal Cti, Q signal Ctq) (hereinafter, also referred to as “body motion amplitude”) is less than a predetermined amplitude, the increasing direction and the decreasing direction of the phase θ cannot be specified. .. Therefore, when the body movement amplitude is equal to or higher than the predetermined value and the phase θ is in the increasing direction, the detection unit 57 determines that the body movement amplitude is “approaching”, and the body movement amplitude is equal to or higher than the predetermined value and the phase θ decreases. If it is in the direction, it is determined to be "separation", and if the body movement amplitude is less than a predetermined value, it is determined to be "undetermined".

Here, the body movement amplitude is calculated by the body movement calculation unit 56. Typically, as the body movement amplitude, the combined amplitude of the amplitude of the I signal Cti and the amplitude of the Q signal Ctq (that is, the distance from the "0" point on the IQ plane in FIG. 7) is used. The combined amplitude is represented by SQRT {(amplitude of I signal Cti) ^ 2 + (amplitude of Q signal Ctq) ^ 2}.

Here, the difference between the number of approaches determination and the number of separation determinations in a unit period is referred to as "point difference". When a point difference of N times (N: natural number) or more out of 40 times occurs in 0.1 seconds, which is the unit period, the action corresponding to the one with the larger number of judgments is detected as the action of the subject within the unit period. NS. This N times is the threshold value of the point difference, and in the present embodiment, the point difference threshold value N = 20 times. When the point difference is less than 20 times, the movement of the subject in the unit period is detected as undetermined. The point difference threshold value may be appropriately selected depending on the performance of the microwave Doppler sensor 160 of the monitoring device 100, the installation position, and the installation environment.

Here, using a sampling period of 2.5 milliseconds (that is, 1/40 of 0.1 second), it is determined whether the subject's movement in a unit period is approach movement, separation movement, or undetermined movement. Although an example of detection has been described, the sampling period is not limited to 2.5 milliseconds.

Within the unit period, the judgment of "approach / separation / undecided" is made for each sampling cycle so that the sum of the number of approach judgments, the number of separation judgments, and the number of undetermined numbers is the threshold value K or more (K is a natural number of 4 or more). It may be configured to be performed. In this case, when a point difference of N = K / 3 times (rounded up in the case of a decimal point) occurs, the motion of the subject in a unit period may be detected as an approaching motion or a detaching motion.

For example, when K = 4, N = 1.4, and in the following combinations, the movement of the subject in the unit period is detected as the separation movement. Specifically, when the number of separation judgments is 4 out of K = 4 times, which is the total number of judgments during the unit period (point difference = 4> 1.4), the number of separation judgments is 3 out of 4 times. , When the number of undetermined times is 1 (point difference = 3> 1.4), when the number of separation judgments is 2 out of 4 times and the number of undetermined times is 2 (point difference = 2> 1.4) ), And when the number of separation judgments is 3 times and the number of approach judgments is 1 out of 4 times (point difference = 2> 1.4), the movement of the subject in the unit period is detected as the separation movement. NS. The approaching motion may be considered in the same manner.

In this way, the detection unit 57 determines, for each unit period, whether the subject's motion is approaching motion, separating motion, or undeterminable based on the I-channel signal and the Q-channel signal. The motion according to the judgment result is detected as the motion of the subject.

Specifically, first, in order to detect the approaching motion and the detaching motion in the unit period, the detection unit 57 performs the approaching motion and the detaching motion of the subject a plurality of times for each sampling time shorter than the unit period. Alternatively, it is determined whether the determination is impossible. Next, the detection unit 57 determines whether the subject's movement in the unit period is approaching, separating, or undecidable, based on the number of approach determinations, separation determinations, and undecidable times within the unit period. Is determined. Further, the judgment result in this unit period is used to grasp the movement (approaching movement, separation movement or undecidable) of the subject during the duration of the movement or a predetermined time.

In the first to fifth embodiments, the approaching motion, the detaching motion, and the undetermined determination method in the unit period are the same. In the first to third embodiments, the rise determination based on the number of approaches and the number of separations in the duration of the operation is executed by using the determination for each unit period. In the fourth and fifth embodiments, the rise determination based on the number of approaches and the number of separations in a predetermined time is executed by using the determination for each unit period.

The details of the detection method of approaching motion and separating motion in this unit period are as follows. In the detection unit 57, the point difference (absolute value) between the number of approach determinations and the number of separation determinations within a unit period is equal to or greater than the point difference threshold value N, and the number of approach determinations is larger than the number of separation determinations. In this case, the movement of the subject in a unit period is detected as an approaching movement. When the point difference (absolute value) is equal to or greater than the point difference threshold value N and the number of separation determinations is larger than the number of approach determinations, the detection unit 57 performs the movement of the subject in a unit period. Detect as. When the point difference (absolute value) is less than the point difference threshold value N, the detection unit 57 detects the motion of the subject in the unit period as undetermined (that is, undeterminable motion).

Again, with reference to FIG. 5, the determination unit 58 is based on the number of approaching movements and the number of separating movements during the duration of the movement including at least one of the approaching movement and the separating movement of the subject. , Determine if the subject has risen. The start time of the duration is the time when the subject's movement (at least one of approach movement and separation movement) is detected. However, it is assumed that the movement of the subject is not detected within the past predetermined time Tx1 (for example, 1 second: defined as the starting point blank period) from that time point. The end point of the continuation period is the end point of the operation, and the next operation is not detected even after a predetermined time Tx2 (for example, 1 second: defined as a blank period at the end point) elapses after the latest operation is detected. , The time when the latest operation is detected.

As shown in FIG. 4, it is assumed that the monitoring device 100 is installed under the bed 250. For example, in the duration (for example, 4 seconds), the number of approaching motions detected by the detection unit 57 for each unit period (0.1 seconds) is 5, the number of separation operations is 20, and the approaching operation and separationing are performed. It is assumed that the number of undetermined times in which the operation is not detected is 15 times. In this case, the determination unit 58 determines that the subject has risen during the continuation period because the number of separation operations is larger than the number of approach operations. When the number of approaching movements is larger than the number of separation movements, the determination unit 58 determines that the subject has laid down during the continuation period.

Even if the subject turns over, there is a possibility that the subject slightly approaches the monitoring device 100 or the subject slightly separates from the monitoring device 100. Therefore, it is assumed that it may not be possible to determine whether the subject has performed the rising motion or the rolling motion based on only the number of approaching motions and the number of separating motions. Therefore, the determination unit 58 may determine whether or not the subject has risen by considering not only the phase θ of the reflected wave on the IQ plane but also the magnitudes of the amplitudes of the I signal Cti and the Q signal Ctq. ..

Specifically, the directivity pattern of the planar antenna in the monitoring device 100 has a side lobe (see FIG. 3) having a small amplitude component. Therefore, the amplitude of the reflected signal is smaller when the subject rolls over to the left and right than when the subject gets up (or when the subject lies down). In addition, since the basic operation time for turning over is shorter than the basic operation time for getting up, when the subject turns over to the left or right than when the subject gets up (or when the subject lies down). The integrated value of the body movement amplitude during the continuous movement period is smaller. Therefore, by comparing the absolute value of the amplitude (body movement amplitude) of the reflected wave (specifically, the body movement signal I signal Cti and the Q signal Ctq) with the predetermined threshold value Th1, the subject can perform. It is possible to distinguish between the state of getting up and the state of the subject lying down (including turning over).

The determination unit 58 executes the body movement amplitude averaging process every predetermined time (for example, 1 second). For example, when the sampling rate is 400 Hz (that is, sampling every 2.5 milliseconds), the determination unit 58 executes a process of averaging 400 body motion amplitudes (that is, the number of samplings per second). Next, the determination unit 58 calculates the integrated value of the body movement amplitude during the duration of the rising motion (or turning motion). The integrated value is a value obtained by integrating (integrating) the average value of the body movement amplitude for each predetermined time (for example, 1 second) over the duration. For example, when the duration is 4 seconds, the integrated value is the sum of the average values of the body movement amplitudes for 4 times.

In this case, the determination unit 58 determines that the subject has risen when the integrated value of the body movement amplitude is equal to or greater than the threshold value Th1 and the number of separation movements is larger than the number of approach movements. In other words, the determination unit 58 determines that the subject has not risen when the integrated value of the body movement amplitude is less than the threshold value Th1 regardless of the number of approaches and detachments. As described above, the determination unit 58 determines that the movement is a rising motion only when both the predominance of the number of approaching / separating motions and the body movement amplitude value are satisfied. The threshold value Th1 is a digital value when the amplitudes (voltages 0V to 3.3V) of the analog signals Sti and Stq, which are analog values of the body movement amplitude, are AD-converted. The user can arbitrarily change the setting of the threshold value Th1 according to the installation status of the monitoring device 100. For example, in an environment with a lot of noise components such as when a plurality of people are present in one room, the threshold Th1 is significantly changed.

In this embodiment, the configuration in which the synthetic amplitude is used as the body movement amplitude will be described, but the absolute value of the amplitude of the I signal Cti or the absolute value of the amplitude of the Q signal Ctq may be used. Further, as the body movement amplitude, the sum of the absolute value of the amplitude of the I signal Cti and the absolute value of the amplitude of the Q signal Ctq may be used.

The above-mentioned rising-up determination method is a rising-up determination method according to the first embodiment, and will be specifically described in the following <Example 1>.

The state estimation unit 52 estimates the state of the subject based on the heart rate Hn, the respiration rate Bn, and the determination result of the determination unit 58. Here, it is assumed that the monitoring device 100 is attached to the vicinity of the bottom 252 of the bed 250 as in the example of FIG. In this case, if the subject on the bed 250 is in a normal state, it is considered that normal heart rate Hn and respiratory rate Bn are detected. For example, the normal range Xh of the heart rate Hn is 50 to 90 times / minute, and the normal range Xb of the respiratory rate Bn is 10 to 20 times / minute.

The state estimation unit 52 estimates various states of the subject based on a combination of the presence / absence of body movement (that is, the presence / absence of body movement amplitude), the heart rate Hn, the respiratory rate Bn, the presence / absence of the rising determination history, and the like. As a typical example, when the determination unit 58 does not determine that the subject is awake (that is, there is no awakening history), the state estimation unit 52 has at least one of the heart rate Hn and the respiration rate Bn. When it is out of the reference range, it is estimated that the subject is in an abnormal state. For example, when the heart rate Hn is outside the normal range Xh, the state estimation unit 52 estimates that the heart rate is abnormal, and when the respiratory rate Bn is outside the normal range Xb, the state estimation unit 52 estimates that the respiratory abnormality is abnormal. do.

Further, the state estimation unit 52 determines that the subject is awake (that is, has a history of awakening) by the determination unit 58, and the heart rate Hn (or respiration rate Bn) is zero. In some cases, it may be presumed that the subject is out of bed 250. Further, in the state estimation unit 52, the subject is out of bed 250 even when the determination unit 58 determines that the subject is awake and there is no body movement. May be estimated. Details of other estimation examples will be described later.

The output control unit 54 outputs warning information based on the determination result of the determination unit 58 and the estimation result of the state estimation unit 52. Specifically, the output control unit 54 warns when the subject receives a determination result that the subject has risen or an estimation result that the subject is in an abnormal state (heartbeat abnormality, respiratory abnormality, etc.). Output information. The output control unit 54 may output the warning information by voice via the speaker 156, or may display the warning information on the display. Further, the output control unit 54 may transmit warning information to the terminal device 200 via the communication interface 158.

For example, when the subject gets up, the output control unit 54 gives warning information such as "Please do not get out of bed yet", "When you leave the bed, turn on the lamp and act slowly", "A caregiver comes". A message such as "Please wait until" is output as a voice to call attention. Further, the output control unit 54 may transmit information indicating that the subject has risen up to the terminal device 200 as warning information.

<Example>
An embodiment in the case where the monitoring device 100 is installed as shown in FIG. 4 will be described with reference to FIGS. 8 to 10. FIG. 8 is a diagram showing time-dependent changes in approaching motion, separating motion, and body motion amplitude according to the first embodiment.

Specifically, FIG. 8A is a diagram showing the time change of the approaching motion and the separating motion detected by the monitoring device 100. The horizontal axis of FIG. 8A is time, and the vertical axis shows the number of detections of approaching motion or separating motion. FIG. 8B is a diagram showing the time change of the body movement amplitude calculated by the monitoring device 100. The horizontal axis of FIG. 8B is time, and the vertical axis is the magnitude of body movement amplitude. The unit of the magnitude of the amplitude is an arbitrary unit (au), and indicates the intensity amplitude (corresponding to the voltage component) of the reflected signal from the subject. The body movement amplitude is averaged every predetermined time (for example, 1 second). Here, the subject performs a rising motion during the duration T1, a bed resting motion during the duration T2, a rolling motion during the duration T3, and a rolling motion (returning motion) during the duration T4. And.

As described above, in the monitoring device 100, the point difference (absolute value) in the unit period (for example, 0.1 second) is the case where the point difference threshold value N or more, and the number of approach determinations is larger than the number of separation determinations. In this case, the motion of the subject in the unit period is detected as an approach motion, and when the point difference (absolute value) is N or more and the number of separation determinations is larger than the number of approach determinations, the unit is The movement of the subject during the period shall be detected as a separation movement.

With reference to FIG. 8A, the period from time t0 to time t1 is a blank starting point period (for example, 1 second) in which there is no operation, and the monitoring device 100 operates apart from time t1 to time t2. Is being detected. The number of separation operations detected at this time is A1. From time t3 to time t4, the monitoring device 100 detects an approaching motion. The number of approaching movements detected at this time is N1. Further, the period from the time t4 to the time t5 is an end point blank period (for example, 1 second) after the end of the operation.

The period from time t2 to time t3 is an undetermined period in which approaching motion and separation motion are not detected by the monitoring device 100, and is shorter than the starting point blank period and the ending point blank section (for example, 0.1 second). ~ 0.9 seconds). In the undetermined period, since the point difference (absolute value) is less than the point difference threshold N, the approaching motion and the separating motion are not detected.

Since the monitoring device 100 detects the separation motion of the subject at time t1, it recognizes it as the start time of the continuation period of the motion. Further, since the approaching motion and the detaching motion are not detected even after the lapse of a predetermined time Tx2 from the time t4, the time t4 is recognized as the end point of the continuation period. As a result, the duration T1 becomes a period from time t1 to time t4. The total number of approaching and separating movements K1 in the duration T1 is represented by K1 = A1 + N1.

The monitoring device 100 calculates the integrated value Q1 of the body movement amplitude during the duration T1 (see FIG. 8B). Specifically, the integrated value Q1 is a value obtained by integrating the average value of the body movement amplitude for each predetermined time (for example, 1 second) over the duration T1.

Hereinafter, similarly, in the duration T2 in which the bed resting motion (hereinafter, simply referred to as “bed resting motion”) is performed, the monitoring device 100 detects N2 approaching motions and A2 detaching motions (hereinafter, it is simply referred to as “bed resting motion”). See FIG. 8 (a)). The monitoring device 100 calculates the integrated value Q2 of the body movement amplitude during the duration T2 (see FIG. 8B). The total number of times K2 in the duration T2 is represented by K2 = N2 + A2.

During the duration T3 in which the rolling motion is performed, the monitoring device 100 detects the detachment motion of A3 and detects the approaching motion of N3 times (see FIG. 8A). The monitoring device 100 calculates the integrated value Q3 of the body movement amplitude during the duration T3 (see FIG. 8B). The total number of times K3 in the duration T3 is represented by K3 = A3 + N3.

In the duration T4 in which the operation of returning to the original state by the rolling motion is performed, the monitoring device 100 detects the approaching motion of N4 times and the detaching motion of A4 times (see FIG. 8A). The monitoring device 100 calculates the integrated value Q4 of the body movement amplitude during the duration T4 (see FIG. 8B). The total number of times K4 in the duration T4 is represented by K4 = A4 + N4.

According to FIG. 8, in the duration T1 in which the rising motion was performed, the number of separations A1 was larger than the number of approaches N1, and in the duration T2 in which the bed rest operation was performed, the number of approaches N2 was larger than the number of separations A2. It turns out that there are many. Further, the durations T1 and T2 are longer than the durations T3 and T4 in which the rolling motion is performed. Further, in the durations T1 and T2, the instantaneous body movement amplitude is larger than that in the durations T3 and T4. As a result, the integrated values Q1 and Q2 of the body movement amplitude are larger than the integrated values Q3 and Q4.

As a result, by appropriately setting the threshold value Th1 of the integrated value, it is possible to distinguish between the rising motion and the bed rest motion and the rolling motion. Further, by determining which of the number of approaches and the number of separations is larger during the continuation period, it is possible to distinguish between the rising motion and the bed rest motion.

FIG. 9 is a diagram showing the experimental results according to the first embodiment. The subject repeats the rising motion and the bed rest motion twice, and performs the motion of turning over to the right, the motion of returning to the original position, the motion of turning over to the left, and the motion of returning to the original position. Further, in FIG. 9, for each of the rising motion, the bed rest motion, and the rolling motion, the duration, the integrated value of the body movement amplitude, the number of approaching motions, the number of separation motions, the total number of approaching motions and the separation motions, and the number of undetermined times are shown. The result of is shown.

With reference to FIG. 9, in the first rising motion (corresponding to “rising motion 1” in FIG. 9), the duration is 4 seconds, the integrated value of the body movement amplitude is 11329, and the number of approaching motions. (Hereinafter, simply referred to as "the number of approaches") is 0, the number of separation operations (hereinafter, also simply referred to as "the number of separations") is 27, and the total number is 27, which is undetermined. The number of times is 13 times. As described above, the monitoring device 100 detects the approaching motion and the separating motion every 0.1 seconds, which is a unit period. In this case, since the detection is performed 10 times per second and the duration is 4 seconds, the maximum number of detections during the duration is 40 times. Therefore, the total of the total number of times (here, 27 times) and the number of undetermined times (here, 13 times) is the maximum number of detections. The number of undetermined times can be reduced by optimizing the filter constants of HPF82I and 82Q in FIG.

Further, it can be seen that the number of separations is larger than the number of approaches during the rising motion, and the number of approaches is greater than the number of separations during the bed rest operation. Further, during the rising motion and the bed resting motion, the integrated value of the body motion amplitude is larger and the duration of the motion is longer than that during the rolling motion.

By comparing the number of approaches and the number of separations, it is possible to distinguish between the rising motion and the bed rest motion. Further, by setting the threshold value Th1 to 7500 and comparing the integrated value of the body movement amplitude with the threshold value Th1, it is possible to distinguish between the rising motion and the bed rest motion and the rolling motion. In addition, by comparing the duration of the movement, it is possible to distinguish between the rising movement and the turning movement. For example, when the duration of the operation is equal to or longer than the predetermined duration (for example, the duration T1 in which the rising operation is performed), it can be determined that the operation is the rising operation. In this way, it is possible to determine the rising motion only when the conditions of the duration and the integrated value of the body movement amplitude are satisfied, and it is possible to reduce the determination error.

Here, by optimizing the threshold value K for the number of times the point difference is determined for each sampling cycle and the point difference threshold value N, the approaching operation, the separation operation, and the undetermined detection accuracy every 0.1 seconds are improved. be able to. As a result, it is possible to improve the determination accuracy of the rising motion, the bed rest motion, and the rolling motion in the durations T1, T2, T3, and T4 of each motion.

In summary, the monitoring device 100 (determination unit 58) determines that the rising operation has been performed when the number of separations during the duration is larger than the number of approaches and the integrated value of the body movement amplitude is the threshold Th1 or more. do. When the number of approaches during the duration is larger than the number of separations and the integrated value of the body movement amplitude is the threshold Th1 or more, the determination unit 58 determines that the bed rest operation has been performed. Further, when the integrated value of the body movement amplitude is less than the threshold value Th1 and the duration of the movement is less than the predetermined duration (for example, the duration T1 in which the rising motion is performed), the determination unit 58 turns over. It may be determined that the operation has been performed.

Preferably, the following preparations are made before the start of use of the monitoring device 100. Specifically, for the subject, 1) getting up, 2) lying down, 3) turning over, 4) turning over, and 5) turning over continuously are repeated a plurality of times. NS. Then, for each of the movements 1) to 5), the average value of the duration and the average value of the integrated value of the body movement amplitude are calculated. It is preferable to determine the predetermined duration (here, the duration T1 of the rising motion) based on the calculation result of the duration obtained by the motion learning prepared in advance in this way. Further, based on the calculation result of the integrated value of the body movement amplitude (Q1 to Q4), the threshold value Th1 of the body movement amplitude that distinguishes the rising motion and the rolling motion, and the threshold value Th2 of the integrated value of the body motion amplitude related to the continuous rolling motion. It is preferable to determine (described later). As a result, it is possible to reflect the individual differences of each subject with respect to the predetermined duration and the threshold values Th1 and Th2, and more accurate determination becomes possible.

The determination unit 58 may be configured to distinguish between the rising motion and the bed resting motion by comparing the ratio of the number of approaches (or the number of separations) to the total number of times with a predetermined ratio (for example, 0.8). .. For example, the determination unit 58 may determine that the rising operation has been performed when the integrated value of the body movement amplitude is the threshold value Th1 or more and the ratio of the number of separations to the total number of times is equal to or more than a predetermined ratio. .. Further, the determination unit 58 may determine that the bed rest operation has been performed when the integrated value of the body movement amplitude is the threshold value Th1 or more and the ratio of the number of approaches to the total number of times is equal to or more than a predetermined ratio. ..

When the monitoring device 100 determines that the subject has risen, the monitoring device 100 records the determination time together with the determination result, and outputs information (message, etc.) calling attention to the subject by voice. Further, the monitoring device 100 transmits information indicating that the subject is in a standing state to the terminal device 200. As a result, it is possible to prevent the subject from falling from the bed 250, and the caregiver can quickly rush to the subject.

In addition, even if the rolling motion continues, the subject is suspected of having an abnormality. For example, it is assumed that the subject repeatedly rolls over when he / she wants to go to the bathroom. In addition, when the rolling motion is repeated, the possibility of falling from the bed 250 increases. Therefore, it is necessary to be notified of warning information even in such a case.

For example, when the subject repeatedly turns over and down continuously many times, the approaching motion and the detaching motion are continuously detected, so that the duration is extended. Therefore, it is assumed that the integrated value of the body movement amplitude becomes very large, and becomes larger than the integrated value due to the rising motion and the bed rest motion. Therefore, it is not possible to distinguish between the continuous rolling motion, the rising motion, and the bed rest motion only by the threshold value Th1.

Therefore, the monitoring device 100 (determination unit 58) sets a threshold value Th2 (for example, 15000) that is larger than the threshold value Th1. The determination unit 58 determines that the rolling motion is continuously occurring when the integrated value of the body movement amplitude reaches the threshold value Th2 or more regardless of the number of approaches and the number of separations during the continuation period. In this case, the output control unit 54 transmits information indicating that an abnormality has occurred to the subject to the terminal device 200 as warning information.

<Example of state estimation>
The monitoring device 100 can estimate the state of the subject according to the presence or absence of body movement, heartbeat, respiration, and awakening history. FIG. 10 is a diagram showing an example of estimating the state of the subject according to the first embodiment.

With reference to FIG. 10, body movement "Yes" indicates a case where the body movement amplitude is equal to or more than the reference threshold value, and body movement "No" indicates a case where the body movement amplitude is less than the reference threshold value. .. That is, the body movement calculation unit 56 determines that the subject has body movement when the body movement amplitude is equal to or more than the reference threshold value, and determines that the subject has body movement when the body movement amplitude is less than the reference threshold value. Judge that there is no movement. A heart rate "yes" indicates a case where the heart rate Hn is detected (or a case where the heart rate Hn is within the normal range Xh), and a heart rate "no" indicates a case where the heart rate Hn is zero. Respiratory "presence" indicates the case where the respiratory rate Bn is detected (or is within the normal range Xb), and respiration "absent" indicates the case where the respiratory rate Bn is zero. The wake-up history "Yes" indicates the case where it is determined that the person has woken up, and the wake-up history "No" indicates the case where it is not determined that the person has woken up.

In FIG. 10, patterns P1 to P8 are exemplified according to the presence or absence of body movement, heartbeat, and respiration. Hereinafter, some patterns will be specifically described.

For example, in pattern P1, when the wake-up history is "yes", it is presumed that the person moves to the next action on the bed, and when the wake-up history is "no", it is presumed to be a stable sleep state. .. In pattern P2, when the rising history is "yes", it is estimated to be a dynamic state in which some movement is performed on the bed, and when the rising history is "no", it is estimated to be an apnea state. NS.

In the pattern P6, when the rising history is "Yes", it is estimated that the subject has left the bed 250 and is present in the vicinity of the bed 250 (or is stationary on the bed 250). Will be done. On the other hand, when the rising history is "none", it is estimated that the subject is in an abnormal state. In the pattern P8, when the rising history is “Yes”, it is presumed that the subject has left the bed 250 and does not exist in the vicinity of the bed 250. That is, the state estimation unit 52 estimates that the subject has left the bed 250 when it is determined that the subject has risen, the heart rate is zero, the respiratory rate is zero, and there is no body movement. do. On the other hand, when the rising history is "none", it is estimated that the subject is in an abnormal state with a high degree of urgency. Other patterns are as shown in FIG.

As described above, the monitoring device 100 (state estimation unit 52) can estimate the state of the subject. Typically, the monitoring device 100 (output control unit 54) outputs warning information when it is estimated that the subject is in an abnormal state. In this way, the monitoring device 100 can output warning information not only when the subject gets up but also when it is estimated that an abnormality has occurred in the subject.

<Processing procedure>
FIG. 11 is a diagram showing an example of a processing procedure of the monitoring device 100 according to the first embodiment. Each step of the following monitoring device 100 is mainly realized by the microprocessor 45 of the control circuit 152 executing a program stored in the memory 154.

With reference to FIG. 11, the monitoring device 100 irradiates the subject with microwaves via the microwave Doppler sensor 160 (step S10). The monitoring device 100 receives the reflected wave of the microwave via the microwave Doppler sensor 160 (step S12), and generates an I-channel signal and a Q-channel signal from the reflected wave signal (step S14).

The monitoring device 100 detects (calculates) the heart rate Hn and the respiratory rate Bn of the subject using the I-channel signal and the Q-channel signal (step S16). Specifically, the heart rate calculation unit 60 executes the above-mentioned heart rate calculation process, and the respiration calculation unit 70 executes the above-mentioned respiration rate calculation process.

Further, the monitoring device 100 uses the I-channel signal and the Q-channel signal to detect the number of times the subject approaches and the number of times the subject leaves the monitoring device 100 during the continuation period during which the subject's operation continues (). Step S18). The monitoring device 100 calculates the integrated value of the body movement amplitude during the duration (step S20). The monitoring device 100 executes the rising motion determination process of the subject based on the number of approaches, the number of separations, and the integrated value (step S22). Specifically, the determination unit 58 executes the above-mentioned rising operation determination process.

Next, the monitoring device 100 estimates the state of the subject based on the result of the rising motion determination, the heart rate and the respiratory rate, and the presence or absence of body movement (step S24). Specifically, the state estimation unit 52 executes the above-mentioned state estimation process. Then, the monitoring device 100 outputs warning information based on a predetermined condition (step S26). Specifically, the output control unit 54 executes the above-mentioned output processing of the warning information. For example, when the subject gets up and an abnormality of the subject is presumed, warning information is output.

Before starting the above flow, the monitoring device 100 obtains a threshold value of the noise level and distinguishes the original respiratory signal, heartbeat signal, and body movement signal from the noise.

Before executing each process of FIG. 11 above, the microprocessor 45 executes an environmental calibration for the respiratory component, the heartbeat component, and the body movement component. Specifically, the monitoring device 100 senses for a certain period of time (for example, 1 minute) in an environment where there is no moving object including the subject in the space where the monitoring device 100 is installed, and the respiratory amplitude, the heartbeat amplitude, and the like. Calculate the average value (noise level) of the body movement amplitude. Then, as a threshold value for distinguishing the noise component and the signal component with respect to the body movement amplitude, a value several times (for example, 3 times to 6 times) the average value (noise level) of the body movement amplitude is set as the reference threshold value of the body movement amplitude. Set as. Similarly, regarding the respiratory amplitude, a threshold value larger than the average value of the respiratory amplitude is set as a threshold value for distinguishing the noise component and the signal component. Regarding the heartbeat amplitude, a threshold value larger than the average value of the heartbeat amplitude is set as a threshold value for distinguishing the noise component and the signal component. In this way, the original respiration / heartbeat / body movement signal and the noise level are distinguished by setting the threshold value for determining the presence / absence of the heartbeat / respiration / body movement signal.

<Advantage>
According to the first embodiment, by detecting the body movement of the subject in a non-contact manner, it is possible to distinguish between the rising motion and the rolling motion of the subject, so that the rising motion can be accurately determined. When the subject gets up, warning information calling attention is output, and information indicating the getting up operation is transmitted to an external device. Therefore, it is possible to prevent the subject from falling from the bedding. The caregiver can quickly reach the subject. Warning information is also output when an abnormal state of the subject is estimated.

[Embodiment 2]
In the second embodiment, an installation method of the monitoring device 100 different from that of the first embodiment will be described.

FIG. 12 is a diagram for explaining an installation method of the monitoring device 100 according to the second embodiment. Specifically, FIG. 12A is a schematic view of the subject on the bed when viewed from the side. FIG. 12B is a schematic view of the subject on the bed when viewed from above.

The position of the monitoring device 100 when viewed in a plan view is different between the installation method shown in FIG. 12 and the installation method described in FIG. 4, and the other configurations are the same. Specifically, in the example of FIG. 4, the monitoring device 100 was installed on the center line 181 in the left-right direction of the bed 250, but in the example of FIG. 12, the monitoring device 100 is from the center line 181 to the exit 180b. Is installed at an offset of a distance La (for example, 5 cm to 25 cm) on the 180 side of the bed end where the bed is present (see FIG. 12 (b)).

Typically, the monitoring device 100 is installed so that the peak direction line 111a in the elevation angle direction and the peak direction line 111b in the azimuth direction face the center side of the bed 250 when the subject gets up. Since the radio wave has a beam width, the monitoring device 100 may be installed so that the peak direction line 111b in the azimuth direction is along the longitudinal direction of the bed 250.

In the example of FIG. 12, similarly to the example of FIG. 4, when the subject gets up from the bed 250, the subject is present on the peak direction line 111a, and the subject is present from the monitoring device 100. Separate. When the subject lies on the bed 250, the subject is present on the peak direction line 111a and the subject approaches the monitoring device 100. In the second embodiment, since the monitoring device 100 is installed offset from the center line 181, the approaching motion and the separating motion detected at the time of the rising motion are mixed as compared with the case of the first embodiment. Is assumed. However, the phenomenon that the number of separations is larger than the number of approaches during the rising motion and the number of approaches is greater than the number of separations during the bed rest operation is the same.

As described in FIG. 4, it is the side that descends from the bed 250 (that is, the bed end 180 side) that the subject is likely to fall from the bed 250. For example, the subject performs a specific rolling motion toward the bed end 180 side, climbs over the bedside guard 180a and falls, or moves (slides) along the bedside guard 180a and gets off. There is a possibility of falling from the mouth 180b. In each case, the operation takes more than twice as long as the simple rising operation, and the integrated amplitude value becomes large.

In the second embodiment, the monitoring device 100 is installed at an offset of about La distance from the center line 181 of the bed 250. Therefore, when the subject is present on the bed end 180 side, the body movement amplitude The integrated value of is very large. Thereby, it is possible to determine whether or not the subject is present on the bed end 180 side according to the magnitude of the integrated value of the body movement amplitude.

Specifically, the monitoring device 100 (determination unit 58) according to the second embodiment shows that the number of separations during the duration is larger than the number of approaches and the integrated value of the body movement amplitude is the threshold Th1 or more. It is determined that the rising operation has been performed. When the number of approaches during the duration is larger than the number of separations and the integrated value of the body movement amplitude is the threshold Th1 or more, the determination unit 58 determines that the bed rest operation has been performed.

Further, when the integrated value of the body movement amplitude is less than the threshold value Th1, the determination unit 58 determines that the turning motion is performed on the safe bed end 185 side. When the integrated value of the body movement amplitude is equal to or greater than the threshold value Th2, the determination unit 58 performs a specific turning motion or sliding motion on the bed end 180 side where there is a possibility of falling. Judged as The monitoring device 100 (output control unit 54) outputs warning information when it is determined that the subject has risen up, and when it is determined that the bed end 180 side has been turned over or the sliding motion has been performed.

In the above, the configuration in which the monitoring device 100 is installed offset to the bed end 180 side has been described, but the configuration is not limited to this configuration. For example, by installing two monitoring devices 100 on both sides of the central line 181 respectively, the above determination may be executed by each monitoring device 100.

<Advantage>
According to the second embodiment, the warning information can be output even when a specific rolling motion or sliding motion that is likely to fall from the bed 250 is performed. Other advantages are the same as in the first embodiment.

[Embodiment 3]
In the third embodiment, an installation method of the monitoring device 100 different from the first and second embodiments will be described.

13 and 14 are diagrams for explaining an installation method of the monitoring device 100 according to the third embodiment. Specifically, FIG. 13A is a schematic view of a subject lying on the bed 250 when viewed from the head side. FIG. 13B is a schematic view of a subject standing up on the bed 250 when viewed from the head side. FIG. 14A is a schematic view of the subject on the bed 250 when viewed from the side. FIG. 14B is a schematic view of the subject on the bed 250 when viewed from above.

With reference to FIGS. 13 and 14, the monitoring device 100 according to the third embodiment is installed by using the pole 101 on the bedside guards 180a provided on the side portions (left and right) of the main body 251 of the bed 250. Typically, the monitoring device 100 is installed on the bedside guard 180a on the bed end 185 side.

Further, the monitoring device 100 is attached to the subject at an angle θb = 20 to 40 degrees at a height H of about 60 to 70 cm from the mattress 253. It is preferable that the chest of the subject is present on the peak direction line 111a of the main lobe of the flat antenna. When the bedding is a futon or the like, it may be installed by using a dedicated stand or the like instead of the bedside guard 180a. Alternatively, the monitoring device 100 may be integrated with an alarm clock or the like having an appropriate height.

In addition, when the subject is lying on the bed 250 and when the subject is on the peak direction line 111a and gets up from the bed 250, the subject approaches the monitoring device 100. If the monitoring device 100 is provided at the position, the installation method is not limited to the above. For example, the monitoring device 100 may be configured to be installed on the ceiling.

FIG. 15 is a diagram showing time-dependent changes in approaching motion, separating motion, and body motion amplitude according to the third embodiment. Specifically, FIG. 15A is a diagram showing the time change of the approaching motion and the separating motion detected by the monitoring device 100. The horizontal axis of FIG. 15A is time, and the vertical axis shows the number of detections of approaching motion or separating motion. FIG. 15B is a diagram showing the time change of the body movement amplitude calculated by the monitoring device 100. The horizontal axis of FIG. 15B is time, and the vertical axis is the magnitude of body movement amplitude. Here, the subject moves up in the duration T1, lays down in the duration T2, rolls over in the duration T3, and rolls over in the duration T4.

With reference to FIG. 15 (a), the monitoring device 100 detects the approaching motion between the time ta and the time tb. The number of approaching movements detected at this time is N1. From time tc to time td, the monitoring device 100 detects the separation operation. The number of separation operations detected at this time is A1. The continuation period T1 is a period from time ta to time tb. The total number of approaching and separating movements K1 in the duration T1 is represented by K1 = N1 + A1.

The monitoring device 100 calculates the integrated value Q1 of the body movement amplitude during the duration T1 (see FIG. 15B). Specifically, the integrated value Q1 is a value obtained by integrating the average value of the body movement amplitude for each predetermined time (for example, 1 second) over the duration T1.

Hereinafter, similarly, in the duration T2 in which the bed rest operation is performed, the monitoring device 100 detects the separation operation of A2 times and the approaching operation of N2 times (see FIG. 15A). The monitoring device 100 calculates the integrated value Q2 of the body movement amplitude during the duration T2 (see FIG. 15B). The total number of times K2 in the duration T2 is represented by K2 = N2 + A2.

During the duration T3 in which the rolling motion is performed, the monitoring device 100 detects the approaching motion of N3 and detects the separation motion of A3 times (see FIG. 15A). The monitoring device 100 calculates the integrated value Q3 of the body movement amplitude during the duration T3 (see FIG. 15B). The total number of times K3 in the duration T3 is represented by K3 = A3 + N3.

In the duration T4 in which the operation of returning to the original state by the rolling motion is performed, the monitoring device 100 detects the approaching motion of A4 times and the separation motion of N4 times (see FIG. 15A). The monitoring device 100 calculates the integrated value Q4 of the body movement amplitude during the duration T4 (see FIG. 15B). The total number of times K4 in the duration T4 is represented by K4 = A4 + N4.

According to FIG. 15, in the duration T1 in which the rising motion was performed, the number of approaches N1 was larger than the number of separations A1, and in the duration T2 in which the bed rest operation was performed, the number of separations A2 was larger than the number of approaches N2. There are also many. For this reason, in the example of FIG. 15, unlike the example of FIG. 8, the number of approaches is larger than the number of separations during the rising operation, and the number of separations is larger than the number of approaches during the bed rest operation.

Further, the durations T1 and T2 are longer than the durations T3 and T4 in which the rolling motion is performed. Further, in the durations T1 and T2, the instantaneous body movement amplitude is larger than that in the durations T3 and T4. As a result, the integrated values Q1 and Q2 of the body movement amplitude are larger than the integrated values Q3 and Q4. This point is the same as the example of FIG.

From the above, also in the third embodiment, by appropriately setting the threshold value of the integrated value, it is possible to distinguish between the rising motion and the bed rest motion and the rolling motion. Further, by determining which of the number of approaches and the number of separations is larger during the continuation period, it is possible to distinguish between the rising motion and the bed rest motion.

FIG. 16 is a diagram showing the experimental results according to the third embodiment. The subject repeats the rising motion and the bed rest motion three times, and further repeats a series of motions including the motion of turning over to the right, the motion of returning to the original position, the motion of turning over to the left, and the motion of returning to the original position twice. ..

With reference to FIG. 16, in the first rising motion (corresponding to “rising motion 1” in FIG. 16), the duration is 6 seconds, the integrated value of the body movement amplitude is 11226, and the number of approaches is 30. The number of times is 13, the number of separations is 13, the total number of times is 43, and the number of undetermined times is 17.

With reference to FIG. 16, it can be seen that the number of approaches is greater than the number of separations during the rising motion, and the number of separations is greater than the number of approaches during the bed rest motion. In addition, the integrated value of the body movement amplitude during the rising motion and the bed rest motion is larger than the integrated value during the rolling motion.

Therefore, also in the third embodiment, it is possible to distinguish between the rising motion and the bed resting motion by comparing the number of approaches and the number of separations. Further, for example, by setting the threshold value Th3 to 8000 and comparing the integrated value of the body movement amplitude with the threshold value Th3, it is possible to distinguish between the rising motion and the bed rest motion and the rolling motion.

Further, also in the third embodiment, it is possible to distinguish between the rising motion and the rolling motion by comparing the duration of the motion. For example, when the duration of the operation is equal to or longer than the predetermined duration (for example, the duration T1 in which the rising motion is performed), it can be determined that the motion is the rising motion. When the condition of the integrated value of the body movement amplitude is satisfied, it can be determined that the motion is a rising motion, and the determination error can be reduced.

In summary, the monitoring device 100 (determination unit 58) determines that the rising operation has been performed when the number of approaches during the duration is larger than the number of separations and the integrated value of the body movement amplitude is the threshold Th3 or more. do. When the number of separations during the continuation period is larger than the number of approaches and the integrated value of the body movement amplitude is the threshold value Th3 or more, the determination unit 58 determines that the bed rest operation has been performed. Further, the determination unit 58 determines that the rolling motion is performed when the integrated value of the body movement amplitude is less than the threshold value Th3 and the duration of the motion is less than the predetermined duration (for example, the duration T1). You may judge.

Preferably, the following preparations are made before the start of use of the monitoring device 100. Specifically, for the subject, 1) getting up, 2) lying down, 3) turning over, 4) turning over, and 5) turning over continuously are repeated a plurality of times. NS. Then, for each of the movements 1) to 5), the average value of the duration and the average value of the integrated value of the body movement amplitude are calculated. It is preferable to determine a predetermined duration (here, the duration of the rising motion) based on the calculation result of the duration obtained by the motion learning prepared in advance in this way. Further, based on the calculation result of the integrated value of the body movement amplitude (Q1 to Q4), the threshold value Th3 of the body movement amplitude that distinguishes the rising motion and the rolling motion, and the threshold value Th4 of the integrated value of the body motion amplitude related to the continuous rolling motion. It is preferable to determine (described later). As a result, it is possible to reflect the individual differences of each subject with respect to the predetermined duration and the threshold values Th3 and Th4, and more accurate determination becomes possible.

When the monitoring device 100 determines that the subject has risen, the monitoring device 100 outputs information for calling attention to the subject by voice. Further, the monitoring device 100 transmits information indicating that the subject is in a standing state to the terminal device 200.

As in the first embodiment, the monitoring device 100 may output warning information when it detects a continuous rolling motion. Specifically, the monitoring device 100 (determination unit 58) sets a threshold value Th4 (for example, 15000) larger than the threshold value Th3. The determination unit 58 determines that the rolling motion is continuously occurring when the integrated value of the body movement amplitude reaches the threshold value Th4 or more regardless of the number of approaches and the number of separations during the continuation period. In this case, the output control unit 54 transmits information indicating that an abnormality has occurred to the subject to the terminal device 200 as warning information.

<Advantage>
According to the third embodiment, the same advantages as those of the first embodiment and the second embodiment can be obtained.

[Embodiment 4]
In the fourth embodiment, when the monitoring device 100 is installed under the bed 250 as shown in FIG. 4, the rising determination method according to the first to third embodiments (hereinafter, referred to as “determination method E1” for convenience). A rise determination method different from) will be described.

A rising determination method (hereinafter, referred to as “determination method E2” for convenience) according to the fourth embodiment will be described with reference to FIGS. 4, 17 and 18. In the fourth embodiment, the method of detecting the movement of the subject in the unit period (0.1 seconds) is the same as that of the above-described embodiment, and the method of determining the rise of 0.1 seconds or more is the above-described embodiment. Different from the form.

First, in the rising determination method E1 according to the above-described first to third embodiments, the presence or absence of rising is determined by using "the number of approaches and the number of separations every 0.1 seconds" in the duration of operation (for example, 4 seconds). Was. However, in the rising determination method E2 according to the fourth embodiment, the starting point of the operation (that is, the time when the approaching motion or the detaching motion occurs) is set as the starting point, and within a predetermined time Ts (for example, 1 second) from the starting point. The presence or absence of getting up is determined by using the "number of approaches and the number of separations every 0.1 seconds" in.

Specifically, the determination unit 58 determines that the number of approaches (or the number of separations) within 1 second from the starting point is M or more (an integer of M: 6 to 10) out of 10 times. It is determined that the rising operation has been performed.

For example, as shown in FIG. 4, when the monitoring device 100 is installed on the floor of the bed 250 or the like, when the subject gets up from the bed 250, the subject separates from the monitoring device 100. Here, the detection unit 57 detects the movement (approach, separation, undetermined) of the subject every unit period (0.1 seconds), and 7 out of 10 times, which is the number of detections within 1 second from the starting point. It is assumed that the separation operation is detected. In this case, assuming that the predetermined number of times M = 6, the determination unit 58 determines that the subject has risen because the number of separations within 1 second from the starting point is M or more out of 10 times.

FIG. 17 is a diagram showing the experimental results during the rising operation according to the fourth embodiment. Specifically, FIG. 17A shows the number of approach determinations, the number of separation determinations, and the point difference for each unit period (0.1 seconds) in 4 seconds, which is the entire period including the rising motion. As shown in FIG. 17 (a), in the vertical columns, the number of separation determinations (corresponding to "separation" in the figure), the number of approach determinations (corresponding to "approach" in the figure), and the point difference are shown. , The whole period (4 seconds) is shown by dividing it into 1 second sections. The horizontal row shows 0 to 1 second every 0.1 seconds.

For example, in the unit period of 2.1 seconds to 2.2 seconds from the start of measurement, the number of separation determinations is 35 and the number of approach determinations is 3, so the point difference is 32 times. When the point difference threshold N is 20, since the point difference 32 times is equal to or greater than the point difference threshold N, the movement of the subject in this unit period is detected as a separation movement. Here, the point difference is a value obtained by subtracting the number of approach determinations from the number of separation determinations.

On the other hand, when the number of approach judgments is 20 times or more more than the number of separation judgments in a certain unit period (that is, when the point difference is -20 or less), the movement of the subject in the unit period is detected as an approach movement. Will be done. However, according to FIG. 17A, there is no unit period detected as an approaching motion in the entire period, and a unit detected as a separation motion or undetermined (when the point difference (absolute value) is less than 20). It turns out that there is only a period.

FIG. 17B is a graph for distinguishing the movements (separation movement, approach movement, undetermined) of the subject in each unit period. Here, for convenience, the separation motion, the approach motion, and the undetermined motion are indicated by "-1", "1", and "0", respectively.

With reference to FIG. 17B, the separation operation continues for 2 seconds or more (that is, the determination for 1 second, which is a predetermined time Ts, is performed twice in succession), and the rising operation continues. It is shown that. In this case, the predetermined number of times M may be set to any value of 6 to 10.

FIG. 18 is a diagram showing an experimental result at the time of turning over according to the fourth embodiment. Specifically, FIG. 18A shows the number of approach determinations, the number of separation determinations, and the point difference for each unit period in 4 seconds, which is the entire period including the rolling motion. FIG. 18B is a graph for distinguishing the movements of the subject in each unit period. The configurations of FIGS. 18 (a) and 18 (b) are the same as those of FIGS. 17 (a) and 17 (b), respectively.

When the turning motion is confirmed in 4 seconds with reference to FIG. 18, the period during which the absolute value of the point difference threshold N is 20 or more is 0. It is only for 1 second, and it is undetermined in other unit periods. From this, it can be seen that by setting the point difference threshold value N to 20, the rising motion and the rolling motion can be clearly distinguished.

In this way, when the monitoring device 100 is provided at a position where the subject is separated from the monitoring device 100 when the subject gets up from the bedding (see FIG. 4), the determination unit 58 is the subject. If the number of separation movements is equal to or greater than a predetermined number of times (for example, 6 times) within a predetermined time Ts (for example, 1 second) after the start of the movement, it is determined that the subject has risen. Can be done.

Similarly, when the monitoring device 100 is provided at a position where the subject approaches the monitoring device 100 when the subject gets up from the bedding (see FIGS. 13 and 14), the determination unit 58 is subjected to the subject. It is determined that the subject has risen when the number of approaching movements is equal to or greater than a predetermined number of times (for example, 6 times) within a predetermined time Ts (for example, 1 second) after the examiner starts the movement. can do.

Further, referring to FIG. 17, in the 1-second section of 1 second to 2 seconds, the 1-second section of 2 seconds to 3 seconds, and the 1-second section of 3 seconds to 4 seconds, the unit period detected as the separation motion is It has continued 3 times in a row. Therefore, the determination unit 58 may determine that the subject has risen when the continuous number R of the unit period detected as the separation motion is 3 times or more.

In this way, the determination unit 58 can determine the presence or absence of the rising motion by using the number of approaching motions or separating motions within a predetermined time Ts after the subject starts the motion.

In addition, in order to execute the determination more accurately, the determination unit 58 may determine the presence or absence of the rising motion by further using the integrated value of the body movement amplitude value as in the first to third embodiments. In this case, the determination unit 58 calculates the integrated value of the body movement amplitude at a predetermined time Ts after the subject starts the operation. The integrated value is a value obtained by integrating (integrating) the average value of the body movement amplitude for a predetermined time (for example, every 0.1) in time Ts. For example, when the time Ts is 1 second, the integrated value is a value obtained by adding the average value of the body movement amplitudes for 10 times. For example, when the monitoring device 100 is installed as shown in FIG. 4, the determination unit 58 starts the operation when the integrated value of the body movement amplitude is equal to or higher than the threshold value Thx. Then, when the number of separation actions is equal to or greater than the predetermined number of times within the predetermined time Ts, it is determined that the subject has risen. In other words, the determination unit 58 determines that the subject has not risen when the integrated value of the body movement amplitude is less than the threshold value Thx regardless of the number of approaching motions and detaching motions.

FIG. 19 is a diagram showing other experimental results during the rising operation according to the fourth embodiment. Specifically, FIG. 19 shows an example in which the point difference threshold N is changed to 25 in FIG. FIG. 20 is a diagram showing other experimental results during the rolling operation according to the fourth embodiment. Specifically, FIG. 20 shows an example in which the point difference threshold N is changed to 25 in FIG.

With reference to FIG. 19, it can be seen that the detection tendency of the movement of the subject is substantially the same as that of FIG. On the other hand, referring to FIG. 20, the movement of the subject is detected as undetermined in all the unit periods in the entire period. By changing the point difference threshold value in this way, it is possible to further clarify the rising motion and the rolling motion.

The rising determination method E2 according to the fourth embodiment can also be used in the installation method according to the second embodiment (FIG. 12) and the installation method according to the third embodiment (FIGS. 13 and 14). In this case, depending on the installation method and the hardware performance, the rising operation is determined by either the approaching operation or the separating operation, and the parameters of the predetermined number of times M, the point difference threshold N, and the continuous number of times R may be appropriately adjusted. Preferably, these parameters are set by having the subject test in advance when installing the monitoring device 100 in an actual environment.

For example, as shown in FIG. 12, even when the monitoring device 100 is offset-arranged, the parameters of the predetermined number of times M, the point difference threshold value N, and the continuous number of times R are substantially the same values, but the environment of the room before installation. It is preferable that it is preset according to the subject and the subject.

In this offset arrangement, the beam of radio wave radiation (peak direction line 111a) faces the exit 180b of the bed 250, so that specific rolling, sliding movements, etc. are likely to fall within the detection range, which is similar to the long-time rising operation. It is possible to detect the movement in the direction of separation in real time. In addition, the body movement amplitude value every 0.1 seconds may also be determined. Thereby, it is possible to detect specific turning over, sliding movement, etc. in real time by using the predetermined number of times M, the point difference threshold value N, and the continuous number of times R set under the condition of the rising motion.

<Advantage>
According to the fourth embodiment, it is possible to determine the rising motion and the like within a predetermined time after detecting the approaching motion or the detaching motion without waiting for the series of motions to be completed. Therefore, faster and real-time determination is possible.

[Embodiment 5]
In the fifth embodiment, an example in which the same rise determination method E2 as in the fourth embodiment is applied in the installation configuration of the monitoring device 100 different from the first to third embodiments will be described.

FIG. 21 is a diagram for explaining an installation method of the monitoring device 100 according to the fifth embodiment. Specifically, FIG. 21A is a schematic view of the subject on the bed when viewed from the side. FIG. 21B is a schematic view of the subject on the bed when viewed from above. In FIG. 21, the installation position on the bed 250 is different from the installation position described in FIGS. 4 and 12 to 14, and the other configurations are the same.

With reference to FIG. 21, the monitoring device 100 is the main body 251 of the bed 250 and is attached to the height H from the mattress 253 by using a pole 101 at a height H = about 60 cm to 90 cm. In the example of FIG. 21, the monitoring device 100 is attached to the head side of the subject. Further, the monitoring device 100 is configured to be mountable within a range of a predetermined angle ± θc from the horizontal.

In the example of FIG. 21, the mattress is installed on the mattress 253 side (that is, the subject side) at an angle of θc. Typically, in the monitoring device 100, when the peak direction line 111a of the main lobe (elevation angle direction) radiated from the planar antenna is directed toward the center side of the bed 250 and the subject gets up from the bed 250, the monitoring device 100 is used. The subject is present on the peak direction line 111a and is installed so as to irradiate the subject's back.

According to the installation method shown in FIG. 21, when the subject performs the rising motion, the motion is close to the monitoring device 100 at the initial stage of the rising motion, but after the subject gets up a little, the monitoring device 100 starts. The operation is separated. On the other hand, when the subject lies on the bed 250, the subject is present on the peak direction line 111a in the initial stage of the bed rest operation, and the subject approaches the monitoring device 100, and then the subject approaches the monitoring device 100. Immediately before it comes into contact with the bed 250, it moves away from the monitoring device 100.

FIG. 22 is a diagram showing the experimental results during the rising operation according to the fifth embodiment. Specifically, FIG. 22A shows the number of approach determinations, the number of separation determinations, and the point difference for each unit period (0.1 seconds) in 4 seconds, which is the entire period including the rising motion. The configuration of FIG. 22 (a) is the same as that of FIG. 17 (a).

In the fifth embodiment, the determination method E2 is used as in the fourth embodiment. Therefore, the determination unit 58 starts up when the number of approaches (or the number of separations) within 1 second from the starting point is M or more (an integer of M: 6 to 10) a predetermined number of times out of 10 times. Judge that it was carried out. When the monitoring device 100 is installed as shown in FIG. 21, the determination unit 58 raises the subject when the number of separations within 1 second from the starting point is M or more a predetermined number of 10 times. Judged as

With reference to FIG. 22A, for example, in the unit period of 1.5 seconds to 1.6 seconds from the start of measurement, the number of separation determinations is 29 and the number of approach determinations is 2, so that the point difference is It will be 27 times. When the point difference threshold N is 20, since the point difference 27 times is equal to or greater than the point difference threshold N, the movement of the subject in this unit period is detected as a separation movement.

On the other hand, when the number of approach judgments is 20 times or more more than the number of separation judgments in a certain unit period (when the point difference is "-20" or less in FIG. 22A), the subject in the unit period. The motion of is detected as an approach motion. For example, the approaching motion is detected in the period of 0.2 seconds to 0.5 seconds, which is the initial stage of the rising motion, and the period of 3.6 seconds to 3.9 seconds, which is the completion stage of the rising motion. Recognize.

FIG. 22B is a graph for distinguishing the movements (separation movements, approach movements, undetermined movements) of the subject in each unit period. With reference to FIG. 22B, the separation operation continues for 2 seconds or more (that is, the determination for 1 second, which is the predetermined time Ts, is performed twice in succession), and the rising operation continues. It is shown that. In this case, the predetermined number of times M may be set to any value of 6 to 10.

FIG. 23 is a diagram showing the experimental results at the time of turning over according to the fifth embodiment. Specifically, FIG. 23A shows the number of approach determinations, the number of separation determinations, and the point difference for each unit period in 3 seconds, which is the entire period including the rolling motion. FIG. 23B is a graph for distinguishing the movements of the subject in each unit period.

When the turning motion is confirmed in 3 seconds with reference to FIG. 23, the period detected as the separation motion (that is, the period when the point difference threshold N is 20 or more) is 1.2 seconds to 1. It has only a unit period of 3 seconds and a unit period of 2.3 seconds to 2.4 seconds, and is generally undetermined in other unit periods. From this, it can be seen that by setting the point difference threshold value N to 20, the rising motion and the rolling motion can be clearly distinguished.

Further, referring to FIG. 22, the unit period detected as the separation motion continues three times in succession in the 1-second section of 2 seconds to 3 seconds and the 1-second section of 3 seconds to 4 seconds. Therefore, the determination unit 58 may determine that the subject has risen when the continuous number R of the unit period detected as the separation motion is 3 times or more.

As described above, even in the installation method as shown in FIG. 22, the determination unit 58 uses the determination method E2 to perform an approaching operation or a separation operation within a predetermined time Ts after the subject starts the operation. It is possible to determine the presence or absence of the rising motion by using the number of times. The determination unit 58 may further use the integrated value of the body movement amplitude value to improve the determination accuracy of the presence / absence of the rising motion.

FIG. 24 is a diagram showing other experimental results during the rising operation according to the fifth embodiment. Specifically, FIG. 24 shows an example in which the point difference threshold N is changed to 25 in FIG. 22. FIG. 25 is a diagram showing other experimental results during the rolling operation according to the fifth embodiment. Specifically, FIG. 25 shows an example in which the point difference threshold N is changed to 25 in FIG. 23.

With reference to FIG. 24, it can be seen that the detection tendency of the movement of the subject is substantially the same as that of FIG. 22. On the other hand, referring to FIG. 25, the separation operation is not detected in all the unit periods in the whole period. By changing the point difference threshold value in this way, it is possible to further clarify the rising motion and the rolling motion.

FIG. 26 is a diagram for explaining a modified example of the installation method of the monitoring device 100 according to the fifth embodiment. The installation method of FIG. 26 is the same as the installation method of FIG. 21 in that the monitoring device 100 is arranged by using the pole 101. However, in the installation method of FIG. 26, the monitoring device 100 is offset so as to face the peak direction line 111a in the direction of the exit 180b of the bed 250. Even in this case, the parameters of the predetermined number of times M, the point difference threshold value N, and the continuous number of times R are substantially the same values, but it is preferable to preset them according to the room environment and the subject before installation. ..

In this offset arrangement, the beam of radio wave radiation (peak direction line 111a) faces the exit 180b of the bed 250, so that specific rolling, sliding movements, etc. are likely to fall within the detection range, which is similar to the long-time rising operation. It is possible to detect the movement in the direction of separation in real time. In addition, the body movement amplitude value every 0.1 seconds may also be determined. Thereby, it is possible to detect specific turning over, sliding movement, etc. in real time by using the predetermined number of times M, the point difference threshold value N, and the continuous number of times R set under the condition of the rising operation.
<Advantage>
According to the fifth embodiment, the same advantages as those of the fourth embodiment can be obtained.

[Other embodiments]
(1) In the above, the configuration for detecting the approaching motion and the separating motion by using the turning direction of the locus of the coordinates on the IQ plane at the time of detecting the approaching motion and the separating motion for a unit period has been described. Not limited. For example, the approach and separation may be determined by using the phase of the I-channel signal and the phase of the Q-channel signal.

FIG. 27 is a diagram showing a waveform of a body motion signal detected by the microwave Doppler sensor 160. Here, it is assumed that the subject performs an approaching operation to the microwave Doppler sensor 160 (that is, the monitoring device 100), then a stop operation, and further performs a separation operation from the microwave Doppler sensor 160.

With reference to FIG. 27, there are both positive and negative amplitude components with respect to the zero line 301 where the amplitude is at the reference level (ie, zero). During the approaching operation, the phase Pi of the I-channel signal waveform advances with respect to the phase Pq of the Q-channel signal waveform, and the amplitude of each signal increases as the subject approaches the microwave Doppler sensor 160. During the stop operation, which shifts from the approaching operation to the separating operation, each of the I-channel signal waveform and the Q-channel signal waveform has a small amplitude, a long period, and changes relatively slowly. Then, during the separation operation, the phase relationship between the phase Pi and the phase Pq is inverted (that is, the phase Pq advances with respect to the phase Pi), and the amplitude becomes smaller as the phase is separated.

This makes it possible to determine whether the subject is approaching or distant from the monitoring device 100. Therefore, by utilizing such characteristics, the detection unit 57 has the body motion amplitude (for example, the combined amplitude of the I-channel signal and the Q-channel signal) of a predetermined value or more, and the phase of the I-channel signal is the Q-channel. When the signal is advanced with respect to the phase of the signal, the motion of the subject is detected as an approach motion.

The detection unit 57 can determine how the phases of the I-channel signal and the Q-channel signal advance based on the polarity (that is, positive or negative) of the Q-channel signal at the zero crossing point where the I-channel signal intersects the reference level. For example, when the I-channel signal most recently crosses the zero line 301 from minus to plus (for example, zero crossing point 351), the detection unit 57 determines that the Q-channel signal is a minus signal. The motion is detected as an approach motion.

Similarly, the detection unit 57 detects the motion of the subject as a detachment motion when the body motion amplitude is equal to or higher than a predetermined value and the phase of the Q channel signal is ahead of the phase of the I channel signal. do. For example, when the I-channel signal most recently crosses the zero line 301 from minus to plus (for example, zero crossing point 352), the detection unit 57 determines that the Q-channel signal is a positive signal. The movement is detected as a separation movement. Further, when the body movement amplitude is less than a predetermined value, the detection unit 57 detects the movement of the subject as undetermined.

Further, the detection unit 57 may detect the approaching and separating motion by combining the detection method Z1 using the turning direction of the trajectory of the coordinates on the IQ plane and the detection method Z2 using the advance inversion of the IQ phase. .. For example, the detection unit 57 is based on the detection result J1 of the movement of the subject in the unit period based on the detection method Z1 and the detection result J2 of the movement of the subject in the unit period based on the detection method Z2. The movement of the subject at a predetermined time is detected. If the detection result J1 and the detection result J2 in a certain unit period match, the action of the subject in the unit period is detected as the action indicated by the detection result J1 (or J2), and if they do not match, the action in the unit period is taken. The examiner's action is detected as an undeterminable action.

Further, for example, when the sampling frequency is 400 Hz, the approach operation, the separation operation, and the undetermined determination are determined for each of the detection methods Z1 and Z2 every 2.5 milliseconds. In this case, when the detection unit 57 does not match the result based on the detection method Z1 (for example, "approaching operation") and the result based on the detection method Z2 (for example, "separation operation") at a certain sampling timing, , "Undetermined" (that is, an operation that cannot be determined) is determined.

In this way, the detection unit 57 calculates the number of approach determinations, the number of separation determinations, and the number of undetermined determinations in a unit period by combining the detection methods Z1 and Z2, and also calculates the point difference. Based on the calculated point difference and the point difference threshold value N, the detection unit 57 detects any of approaching motion, separation motion, and undetermined motion of the subject in a unit period. This makes it possible to detect the approaching and separating motions with higher accuracy.

(2) As another embodiment, it is also possible to provide a program that causes a computer to function and execute control as described in the above-described embodiment. Such a program is recorded as a program product by recording it on a non-temporary computer-readable recording medium such as a flexible disk attached to a computer, a CD-ROM (Compact Disk Read Only Memory), a ROM, a RAM, and a memory card. It can also be provided. Alternatively, the program can be provided by recording on a recording medium such as a hard disk built in the computer. The program can also be provided by downloading via the network.

The program may be a program module provided as a part of a computer operating system (OS), in which necessary modules are called in a predetermined array at a predetermined timing to execute processing. In that case, the program itself does not include the above module and the process is executed in cooperation with the OS. A program that does not include such a module may also be included in the program according to the present embodiment.

Further, the program according to the present embodiment may be provided by being incorporated into a part of another program. Even in that case, the program itself does not include the modules included in the other programs, and the processing is executed in cooperation with the other programs. A program incorporated in such another program may also be included in the program according to the present embodiment.

Further, the configuration exemplified as the above-described embodiment is an example of the configuration of the present invention, and can be combined with another known technique, and a part thereof is omitted as long as the gist of the present invention is not deviated. It is also possible to change and configure it.

Further, in the above-described embodiment, the process or configuration described in the other embodiments may be appropriately adopted and implemented.

It should be considered that the embodiments disclosed this time are exemplary in all respects and not restrictive. The scope of the present invention is shown by the scope of claims, not the above description, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

21 oscillator circuit, 22A, 22B, 145A, 145B, 145C, 145D amplifier, 25 transmitting antenna, 30 receiving antenna, 32I, 32Q mixer, 38 90 degree phase shifter, 41 analog signal processing circuit, 43 AD converter, 45 microprocessor , 50 motion monitoring unit, 52 state estimation unit, 54 output control unit, 55 network, 56 body motion calculation unit, 57 detection unit, 58 judgment unit, 60 heartbeat calculation unit, 66I, 66Q, 72I, 72Q fundamental wave detection unit, 67 Heart rate averaging unit, 70 Respiration calculation unit, 73 Respiration averaging processing unit, 100 Monitoring device, 101 pole, 111a, 111b Peak direction line, 149A, 149B, 149C, 149D Signal processing circuit, 152 Control circuit, 154 memory, 156 Speaker, 158 communication interface, 160 microprocessor Doppler sensor, 180,185 bed edge, 180a bedside guard, 180b exit, 181 center line, 200 terminal device, 250 bed, 251 body, 252 bottom, 253 mattress, 1000 monitoring system ..

Claims (24)

A monitoring device for monitoring the subject on the bedding.
A receiving unit that receives the reflected wave of the microwave irradiated to the subject, and
A signal generation unit that generates I-channel signals and Q-channel signals that are orthogonal to each other from the reflected wave signals.
A detection unit that detects the movement of the subject at predetermined time intervals based on the I-channel signal and the Q-channel signal is provided.
The movement of the subject includes at least one of the movement of approaching and the movement of the subject moving away from the monitoring device.
A determination unit that determines whether or not the subject has risen based on the number of approaching movements and the number of separation movements during the duration of the subject's movements.
A monitoring device including an output control unit that outputs warning information when the subject gets up. The monitoring device is provided at a position where the subject approaches the monitoring device when the subject gets up from the bedding.
The monitoring device according to claim 1, wherein the determination unit determines that the subject has risen when the number of approaches is greater than the number of detachments during the duration. The monitoring device is provided at a position where the subject separates from the monitoring device when the subject gets up from the bedding.
The monitoring device according to claim 1, wherein the determination unit determines that the subject has risen when the number of times of the separation operation is larger than the number of times of the approach operation during the continuation period. When the integrated value of the amplitude of the signal of the reflected wave during the duration is less than the first threshold value, the determination unit raises the subject regardless of the number of approaching operations and the number of separation operations. The monitoring device according to claim 1, wherein the monitoring device is determined not to be present. The monitoring device according to claim 4, wherein when the integrated value reaches a second threshold value or more larger than the first threshold value during the continuation period, the output control unit outputs the warning information. A monitoring device for monitoring the subject on the bedding.
A receiving unit that receives the reflected wave of the microwave irradiated to the subject, and
A signal generation unit that generates I-channel signals and Q-channel signals that are orthogonal to each other from the reflected wave signals.
A detection unit that detects the movement of the subject at predetermined time intervals based on the I-channel signal and the Q-channel signal is provided.
The movement of the subject includes at least one of the movement of approaching and the movement of the subject moving away from the monitoring device.
A determination unit that determines whether or not the subject has risen based on the number of approaching movements and the number of separation movements in a predetermined time after the subject starts the movement.
A monitoring device including an output control unit that outputs warning information when the subject gets up. The monitoring device is provided at a position where the subject approaches the monitoring device when the subject gets up from the bedding.
The determination unit determines that the subject has risen when the number of approaches is equal to or greater than a predetermined number of times within the predetermined time after the subject starts the operation. Item 6. The monitoring device according to item 6. The monitoring device is provided at a position where the subject separates from the monitoring device when the subject gets up from the bedding.
The determination unit determines that the subject has risen when the number of times of the separation operation is equal to or more than a predetermined number of times within the predetermined time after the subject starts the operation. Item 6. The monitoring device according to item 6. Based on the I-channel signal and the Q-channel signal, the detection unit determines at predetermined time intervals whether the subject's movement is approaching, separating, or undecidable. The monitoring device according to claim 1 or 2, wherein an operation according to a determination result is detected as an operation of the subject. The detection unit
In the predetermined time, every first time shorter than the predetermined time, it is determined a plurality of times whether the motion of the subject is an approaching motion, a detaching motion, or an undecidable motion.
A claim that determines whether the subject's movements in the predetermined time are approaching, separating, or undecidable, based on the number of approach determinations, the number of separation determinations, and the number of undecidable times within the predetermined time. 9. The monitoring device according to 9. The detection unit
When the difference between the number of approach determinations and the number of separation determinations within the predetermined time is equal to or greater than the predetermined difference, and the number of approach determinations is larger than the number of separation determinations, the said in the predetermined time. The movement of the subject is detected as an approaching movement,
When the difference is equal to or greater than the predetermined difference and the number of times of the separation determination is larger than the number of times of the approach determination, the operation of the subject in the predetermined time is detected as the separation operation. Item 10. The monitoring device according to item 10. The monitoring device according to claim 10 or 11, wherein when the difference is less than the predetermined difference, the detection unit detects the operation of the subject in the predetermined time as an undeterminable operation. The monitoring device according to any one of claims 1 to 12, wherein the detection unit detects the approaching motion and the separating motion based on the locus of the I-channel signal and the Q-channel signal on the IQ plane. .. The one according to any one of claims 1 to 12, wherein the detection unit detects the operation of the subject in the predetermined time based on how the phases of the I-channel signal and the Q-channel signal advance. Monitoring device. The detection unit has a first detection result of the operation of the subject at the predetermined time based on the locus of the I-channel signal and the Q-channel signal on the IQ plane, and the I-channel signal and the Q-channel signal. Any of claims 1 to 12, which detects the movement of the subject in the predetermined time based on the second detection result of the movement of the subject in the predetermined time based on the progress of the phase of The monitoring device according to item 1. The monitoring device according to claim 15, wherein the detection unit detects the operation of the subject in the predetermined time as an undeterminable operation when the first detection result and the second detection result do not match. 14. The detection unit determines how the phases of the I-channel signal and the Q-channel signal advance based on the polarity of the Q-channel signal at the zero crossing point where the I-channel signal intersects the reference level. 16. The monitoring device according to any one of 16. A heart rate calculation unit that calculates the heart rate of the subject based on the reflected wave,
A state estimation unit that estimates the state of the subject based on the determination result of the determination unit and the heart rate is further provided.
The state estimation unit estimates that the subject has left the bedding when the determination unit determines that the subject has risen and the heart rate is zero. Item 2. The monitoring device according to any one of Items 1 to 17. A respiration calculation unit that calculates the respiration rate of the subject based on the reflected wave,
A state estimation unit that estimates the state of the subject based on the determination result of the determination unit and the respiratory rate is further provided.
The state estimation unit estimates that the subject has left the bedding when the determination unit determines that the subject has risen and the respiratory rate is zero. Item 2. The monitoring device according to any one of Items 1 to 17. A body movement calculation unit that determines the presence or absence of body movement of the subject based on the reflected wave,
A state estimation unit that estimates the state of the subject based on the determination result of the determination unit and the presence or absence of body movement of the subject is further provided.
The state estimation unit presumes that the subject has left the bedding when the determination unit determines that the subject has risen and there is no body movement. Item 2. The monitoring device according to any one of Items 1 to 17. A heart rate calculation unit that calculates the heart rate of the subject based on the reflected wave,
A respiration calculation unit that calculates the respiration rate of the subject based on the reflected wave,
A body movement calculation unit that determines the presence or absence of body movement of the subject based on the reflected wave,
A state in which the state of the subject is estimated based on the determination result of the determination unit, the heart rate of the subject, the respiratory rate of the subject, and the presence or absence of body movement of the subject. Further equipped with an estimation unit,
In the state estimation unit, when the determination unit determines that the subject has risen, the heart rate is zero, the respiratory rate is zero, and there is no body movement, the subject The monitoring device according to any one of claims 1 to 17, which is presumed to have left the bedding. When the body movement amplitude of the subject is less than the reference threshold value, the body movement calculation unit determines that the subject has no body movement, and the body movement amplitude of the subject is the reference threshold value. In the above cases, it is configured to determine that the subject has body movement.
The monitoring device according to claim 20 or 21, wherein the reference threshold value is set based on a body movement amplitude calculated in an environment in which a moving body including the subject does not exist. The monitoring device according to any one of claims 1 to 22, wherein the I-channel signal and the Q-channel signal are filtered using a filter having a predetermined cutoff frequency. The monitoring device according to any one of claims 1 to 23, wherein the output control unit transmits the warning information to an external device configured to be able to communicate with the monitoring device.

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