Motionless state determination system, motionless state determination method and program

Abstract

To provide a motionless state determination system, motionless state determination method and program allowing to stably determine using a Doppler sensor that a person to be measured does not perform expected motion.SOLUTION: A Doppler data acquisition unit 20 repeatedly acquires Doppler data representing a measurement result by a Doppler sensor 12 provided toward a person to be measured. A change rate calculation unit 22 calculates a rate of change in values of the Doppler data at each of a plurality of consecutive time points. The motionless state determination unit 26 determines that the person to be measured does not perform expected motion based on the change rate at each of the plurality of time points.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a non-operation state determination system, a non-operation state determination method, and a program, and particularly to a system for determining that an operation that a person to be measured should perform does not appear based on Doppler data.

Background Art

[0002] Various systems for measuring the respiration rate and heart rate of a person to be measured based on Doppler data, which is a measurement result by a Doppler sensor, have been studied. As an example of such a system, Patent Document 1 describes a monitoring device that non-contactedly determines the respiration rate and heart rate by a microwave Doppler sensor.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The inventor is considering determining that an operation that a person to be measured should perform does not appear using a Doppler sensor. Specifically, for example, the inventor is considering determining that the person to be measured is in an apnea state or that the person to be measured has bradyarrhythmia. Here, when the amplitude of Doppler data, which is a measurement result by a Doppler sensor, is small, it may be determined that an operation that a person to be measured should perform does not appear.

[0005] However, for example, when the subject being measured is at a location far from the Doppler sensor, the amplitude of the Doppler data may become small. Therefore, when the above-described determination is made, there is a risk of an incorrect determination that the action that the subject should perform does not appear even though the action that the subject should perform appears. Also, when the threshold value used for determining that the action that the subject should perform does not appear is not appropriate, there is a risk of an incorrect determination that the action that the subject should perform appears even though the action that the subject should perform does not appear.

[0006] The present invention has been made in view of the above problems, and an object thereof is to provide a non-operation state determination system, a non-operation state determination method, and a program that can stably determine that the action that the subject should perform does not appear using a Doppler sensor.

Means for Solving the Problems

[0007] (1) The non-operation state determination system according to the present invention includes an acquisition unit that repeatedly acquires Doppler data indicating a measurement result by a Doppler sensor provided toward a subject, a change rate calculation unit that calculates a change rate of a value of the Doppler data at each of a plurality of consecutive time points, and a non-operation state determination unit that determines, based on the change rate at each of the plurality of time points, that the action that the subject should perform does not appear.

[0008] (2) In the non-operation state determination system according to (1), for each of a plurality of time windows each including a first predetermined number of consecutive time points, a time window change rate total calculation unit that calculates a total of absolute values of the change rates at each of the first predetermined number of time points included in the time window as a time window change rate total corresponding to the time window is further included, and the non-operation state determination unit may determine that the action that the subject should perform does not appear based on an average, a total, or a variance of the time window change rate totals corresponding to each of a second predetermined number of consecutive time windows.

[0009] (3) In the inactivity state determination system described in (1), the inactivity state determination means may determine that the action that the person to be measured should perform does not appear based on the average, total, or variance of the absolute values of the change rates at each of the plurality of time points.

[0010] (4) In the inactivity state determination system described in (1), the inactivity state determination means may determine that the action that the person to be measured should perform does not appear based on the variance of the change rates at each of the plurality of time points.

[0011] (5) In the inactivity state determination system according to any one of (1) to (4), the change rate calculation means calculates the change rate of the value of the Doppler data at each of the plurality of time points for each of the plurality of Doppler sensors, and the inactivity state determination means may determine that the action that the person to be measured should perform does not appear based on the change rates calculated for each of the plurality of Doppler sensors.

[0012] (6) In the inactivity state determination system described in (5), for each of the plurality of time windows each including a continuous first predetermined number of the time points for each of the plurality of Doppler sensors, the total of the absolute values of the change rates at each of the first predetermined number of the time points included in the time window is calculated as an individual time window change rate total corresponding to the time window, and for each of the plurality of time windows, the total of the individual time window change rate totals corresponding to the time window for each of the plurality of Doppler sensors is calculated as a time window change rate total corresponding to the time window. The inactivity state determination means may further include an individual time window change rate total calculation means and a time window change rate total calculation means, and may determine that the action that the person to be measured should perform does not appear based on the average, total, or variance of the time window change rate totals corresponding to each of the continuous second predetermined number of the time windows.

[0013] (7) In the inoperative state determination system according to (5), for each of the plurality of time points, a time point change rate total calculation means for calculating the total of the absolute values of the change rates of each of the plurality of Doppler sensors as the time point change rate total corresponding to the time point, and for each of a plurality of time windows each including a continuous first predetermined number of the time points, a time window change rate total calculation means for calculating the total of the time point change rate totals at each of the first predetermined number of the time points included in the time window as the time window change rate total corresponding to the time window, are further included, and the inoperative state determination means may determine that the operation that the person to be measured should have is not present based on the average, total, or variance of the time window change rate totals corresponding to each of a continuous second predetermined number of the time windows.

[0014] (8) In the inoperative state determination system according to (5), for each of the plurality of time points, a time point change rate total calculation means for calculating the total of the absolute values of the change rates of each of the plurality of Doppler sensors as the time point change rate total corresponding to the time point is further included, and the inoperative state determination means may determine that the operation that the person to be measured should have is not present based on the average, total, or variance of the time point change rate totals corresponding to each of the plurality of time points.

[0015] (9) In the inoperative state determination system according to (5), a variance calculation means for calculating the variance of the change rate of the value of the Doppler data at each of the plurality of time points for each of the plurality of Doppler sensors is further included, and the inoperative state determination means may determine that the operation that the person to be measured should have is not present based on the average or total of the variances of the change rates at each of the plurality of Doppler sensors.

[0016] (10) In the inoperative state determination system according to any one of (1) to (9), the inoperative state determination means may determine whether the person to be measured is in an apneic state.

[0017] (11) In the no-operation state determination system according to any one of (1) to (10), the no-operation state determination means may determine whether the person to be measured has bradyarrhythmia.

[0018] (12) The no-operation state determination method according to the present invention includes steps of repeatedly acquiring Doppler data indicating a measurement result by a Doppler sensor provided facing the person to be measured, calculating a change rate of values of the Doppler data at each of a plurality of consecutive time points, and determining, based on the change rate at each of the plurality of time points, that an operation that should be present in the person to be measured is not present.

[0019] (13) The program according to the present invention is a program for causing a computer to execute steps of repeatedly acquiring Doppler data indicating a measurement result by a Doppler sensor provided facing the person to be measured, calculating a change rate of values of the Doppler data at each of a plurality of consecutive time points, and determining, based on the change rate at each of the plurality of time points, that an operation that should be present in the person to be measured is not present. This program may be stored in a computer-readable information storage medium.

Advantages of the Invention

[0020] According to the present invention, it is possible to stably determine that an operation that should be present in the person to be measured is not present by using a Doppler sensor.

Brief Description of the Drawings

[0021]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5A

Figure 5B

Figure 6A

Figure 6B

Embodiment for Carrying out the Invention

[0022] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0023] FIG. 1 is a configuration diagram of an inoperative state determination system 1 according to an embodiment of the present invention. As shown in the figure, the inoperative state determination system 1 includes a signal processing device 10 and a Doppler sensor 12. As shown in FIG. 1, the Doppler sensor 12 is provided facing the person to be measured.

[0024] Also, in the example of FIG. 1, the Doppler sensor 12 is attached to the headboard of the bed 14. Note that the inoperative state determination system 1 according to the present embodiment may include a plurality of Doppler sensors 12. Here, the plurality of Doppler sensors 12 may be provided symmetrically with respect to the center line of the bed 14 (a line passing through the center in the width direction of the bed 14 and extending in the length direction of the bed 14). Also, the plurality of Doppler sensors 12 may be arranged side by side perpendicular to the length direction of the bed 14 (the direction along the center line of the bed 14). Also, the plurality of Doppler sensors 12 may be arranged in a row at equal intervals.

[0025] The Doppler sensor 12 is provided so as to face the length direction (longitudinal direction) of the bed 14, and emits microwaves in the length direction of the bed 14. The microwaves are reflected by the chest of the subject sleeping on the bed 14, and the Doppler sensor 12 receives the reflected waves. The Doppler sensor 12 generates a Doppler signal indicating the movement of the chest associated with breathing from the reflected waves, and outputs Doppler data obtained by digitizing this Doppler signal. Note that the microwaves emitted from the Doppler sensor 12 have slightly shifted frequencies, thereby preventing mutual interference.

[0026] Due to the Doppler effect, the reflected waves are frequency-shifted, and by observing this, the respiratory rate of the subject can be obtained. The reflected waves are detected as a Doppler signal including an I signal that is in-phase component with the transmitted wave and a Q signal that is the quadrature component by quadrature detection, and output to the signal processing device 10 in digital format. The Doppler signal input to the signal processing device 10 is time-series data, indicating the amplitudes (I component and Q component) at each time.

[0027] The signal processing device 10 may be configured by a known computer including, for example, a CPU, a memory, an input device, and a display, and generates the respiratory rate of the subject based on the Doppler signal output from the Doppler sensor 12.

[0028] FIG. 2 is a functional block diagram of the signal processing device 10 according to an embodiment of the present invention. As shown in the figure, the signal processing device 10 includes a Doppler data acquisition unit 20, a change rate calculation unit 22, a determination index calculation unit 24, and a no-operation state determination unit 26. These functional blocks are realized by executing a signal processing program in the signal processing device 10 which is a computer. This signal processing program may be stored in various computer-readable information storage media such as a semiconductor memory, and loaded from the medium into the signal processing device 10. Alternatively, it may be downloaded to the signal processing device 10 via a data communication line such as the Internet.

[0029] The Doppler data acquisition unit 20 repeatedly acquires Doppler data indicating the measurement results by, for example, a Doppler sensor 12 provided facing the subject to be measured. Here, the Doppler data acquisition unit 20 may repeatedly acquire Doppler data indicating the measurement results from each of the plurality of Doppler sensors 12. Here, the value of the Doppler data acquired by the Doppler data acquisition unit 20 may be a value obtained by performing preprocessing (data processing) such as cutting of the DC component, filtering, and various corrections on the measurement results themselves (raw data).

[0030] The change rate calculation unit 22 calculates, for example, the change rate of the value of the Doppler data at each of a plurality of consecutive time points. Here, the change rate calculation unit 22 may calculate the change rate of the value of the Doppler data at each of a plurality of consecutive time points for each of the plurality of Doppler sensors 12. The change rate corresponds to, for example, the slope of the tangent line in the graph of the value of the Doppler data. In the present embodiment, the change rate for each of the I data and the Q data is calculated.

[0031] For example, it is assumed that the latest Doppler data is acquired at intervals of 1 millisecond, and the change rate is specified at intervals of 10 milliseconds. In this case, the change rate calculation unit 22 may calculate an approximate curve (which may be an approximate straight line) of the value of the Doppler data from a predetermined time before a certain time point (for example, 5 milliseconds before) to a predetermined time after the certain time point (for example, 5 milliseconds after) by the least squares method. Then, the change rate calculation unit 22 may determine the slope of the approximate curve (which may be an approximate straight line) at the certain time point as the change rate at the certain time point.

[0032] Note that the method for calculating the change rate is not limited to the above. For example, a value obtained by subtracting the value of the Doppler data at a predetermined time before a certain time point (for example, 1 millisecond before) from the value of the Doppler data at a predetermined time after the certain time point (for example, 1 millisecond after) may be calculated. Then, the calculated value may be determined as the change rate at the certain time point. Alternatively, a value obtained by dividing the calculated value by the time difference (for example, 2 milliseconds) may be determined as the change rate at the certain time point.

[0033] The determination index calculation unit 24 calculates, for example, the value of a determination index used to determine that the action that the person to be measured should perform does not appear, based on the change rate calculated by the change rate calculation unit 22. Here, as an example of the determination that the action that the person to be measured should perform does not appear, there is the determination that the person to be measured is in a breathless state. That is, the determination index calculation unit 24 may calculate the value of the determination index used to determine whether the person to be measured is in a breathless state.

[0034] The no-action state determination unit 26 determines, for example, that the action that the person to be measured should perform does not appear, based on the change rate of the value of the Doppler data at each of a plurality of consecutive time points. Here, the no-action state determination unit 26 may determine whether the person to be measured is in a breathless state, based on the change rate of the value of the Doppler data at each of a plurality of consecutive time points. Also, the no-action state determination unit 26 may determine whether the person to be measured is in a breathless state, based on the change rate of the value of the Doppler data at each of a plurality of consecutive time points calculated for each of the plurality of Doppler sensors 12. Also, the no-action state determination unit 26 may determine whether the person to be measured is in a breathless state, based on the value of the determination index calculated by the determination index calculation unit 24.

[0035] Here, an example of the flow of the breathless state determination process performed by the signal processing device 10 will be described with reference to the flowchart illustrated in FIG. 3.

[0036] First, the change rate calculation unit 22 calculates the change rate at each of a plurality of consecutive time points at a predetermined time interval (for example, at 10 millisecond intervals) for each of the plurality of Doppler sensors 12 (S101). Hereinafter, the time point at which the change rate is calculated will be referred to as the change rate calculation time point. In the present embodiment, it is assumed that the change rate calculation time point is common among the plurality of Doppler sensors 12.

[0037] Then, for each of a plurality of small time windows SW (see FIG. 4) each including a continuous first predetermined number (e.g., 10) of change rate calculation time points of each of the plurality of Doppler sensors 12, the determination index calculation unit 24 calculates the sum of the absolute values of the change rates at each of the first predetermined number of change rate calculation time points included in the small time window SW as the individual time window change rate total corresponding to the small time window SW (S102). Here, the sum of the sum of the absolute values of the change rates of the I data and the sum of the absolute values of the change rates of the Q data at each of the first predetermined number of change rate calculation time points included in the small time window SW may be calculated as the individual time window change rate total corresponding to the small time window SW.

[0038] Then, for each of a continuous second predetermined number (e.g., 100) of small time windows SW, the determination index calculation unit 24 calculates the sum of the individual time window change rate totals corresponding to each of the plurality of Doppler sensors 12 for the small time window SW as the time window change rate total corresponding to the small time window SW (S103).

[0039] Then, the determination index calculation unit 24 calculates a value of a determination index used for determining whether the subject is in an apnea state (S104). In the process shown in S104, for example, the average, sum, or variance of the time window change rate totals corresponding to each of a continuous second predetermined number of small time windows SW may be calculated as the value of the determination index corresponding to a large time window LW (see FIG. 4) including the second predetermined number of small time windows SW.

[0040] FIG. 4 schematically shows small time windows SW(1) to SW(100) which are 100 consecutive small time windows SW. In the present embodiment, the start timing of each small time window SW is shifted by the above-described predetermined time (e.g., 10 milliseconds) each time. As shown in FIG. 4, a part of the time range covered by adjacent small time windows SW may overlap. Further, FIG. 4 schematically shows a large time window LW including 100 consecutive small time windows SW.

[0041] Then, the inactivity state determination unit 26 determines whether the subject is in an apneic state based on the value of the determination index calculated in the process shown in S104 (S105), and the process shown in this process example ends.

[0042] In the process shown in S105, for example, when the value of the determination index corresponding to the large time window LW calculated in the process shown in S104 is equal to or less than a predetermined threshold value, it may be determined that the subject is in an apneic state during the period covered by the large time window LW.

[0043] In the present embodiment, the length of the time range covered by the small time window SW may be equal to or longer than the length of one breath. For example, the length of the time range covered by the small time window SW may be 3 seconds, or 5 seconds, or the like.

[0044] Also, although the first predetermined number and the second predetermined number in the above description are different, the first predetermined number and the second predetermined number may be the same.

[0045] Also, in the process shown in S102, the determination index calculation unit 24 may calculate, for each of a plurality of consecutive change rate calculation time points, the sum of the absolute values of the change rates of each of the plurality of Doppler sensors 12 as the time point change rate sum corresponding to the time point.

[0046] Then, in the process shown in S103, the determination index calculation unit 24 may calculate, for each of a plurality of small time windows SW each including a first predetermined number (for example, 10) of consecutive change rate determination time points, the sum of the time point change rate sums at each of the first predetermined number of change rate determination time points included in the small time window SW as the time window change rate sum corresponding to the small time window SW.

[0047] Then, thereafter, the processes shown in S104 and S105 described above may be executed.

[0048] Further, in the present embodiment, it is not necessary to calculate the value of the determination index corresponding to the large time window LW based on the total time window change rate corresponding to the small time window SW.

[0049] For example, after the process shown in S101, the determination index calculation unit 24 may calculate, for each of a plurality of consecutive (for example, 100) change rate calculation time points, the sum of the absolute values of the change rates of each of the plurality of Doppler sensors 12 as the total time point change rate corresponding to the time point.

[0050] Then, the determination index calculation unit 24 may calculate the average, sum, or variance of the total time point change rates corresponding to each of the plurality of (for example, 100) change rate calculation time points as the value of the determination index corresponding to the time window including the plurality of change rate calculation time points.

[0051] Then, in the same manner as the process shown in S105, the non-operation state determination unit 26 may determine whether the subject is in an apnea state based on the value of the determination index calculated in this way. For example, when the value of the determination index corresponding to the time window is equal to or less than a predetermined threshold, it may be determined that the subject is in an apnea state during the period covered by the time window.

[0052] Further, in the present embodiment, it is not necessary to determine whether the subject is in an apnea state based on the absolute value of the change rate.

[0053] For example, after the process shown in S101, the determination index calculation unit 24 may calculate the variance of the change rate of the value of the Doppler data at each of a plurality of consecutive change rate calculation time points for each of the plurality of Doppler sensors 12.

[0054] Then, the determination index calculation unit 24 may calculate the average or sum of the variances of the change rates in each of the plurality of Doppler sensors 12 as the value of the determination index corresponding to the time window including the plurality of change rate calculation time points.

[0055] Then, in the same manner as the process shown in S105, the non-operation state determination unit 26 may determine whether the subject is in an apneic state based on the value of the determination index calculated in this way. For example, when the value of the determination index corresponding to the time window is less than or equal to a predetermined threshold, it may be determined that the subject is in an apneic state during the period covered by the time window.

[0056] Further, when only one Doppler sensor 12 is included in the non-operation state determination system 1 according to the present embodiment, the change rate of the value of the one Doppler sensor 12 may be calculated at each of a plurality of consecutive change rate determination time points.

[0057] Then, for each of a plurality of small time windows SW each including a first predetermined number of consecutive change rate determination time points, the sum of the absolute values of the change rates at each of the first predetermined number of change rate determination time points included in the small time window SW may be calculated as the total time window change rate corresponding to the small time window SW. Then, the average, total, or variance of the total time window change rates corresponding to each of a second predetermined number of consecutive small time windows SW may be calculated as the value of the determination index corresponding to the large time window LW including the second predetermined number of small time windows SW. Then, based on the calculated value of the determination index, it may be determined whether the subject is in an apneic state during the period covered by the large time window LW.

[0058] Alternatively, the average, total, or variance of the absolute values of the change rates at each of a plurality of consecutive change rate calculation time points may be calculated as the value of the determination index corresponding to the time window including the plurality of change rate calculation time points. Then, based on the calculated value of the determination index, it may be determined whether the subject is in an apneic state during the period covered by the time window.

[0059] Alternatively, the variance of the change rate at each of a plurality of consecutive change rate calculation time points may be calculated as the value of the determination index corresponding to the time window including the plurality of change rate calculation time points. Then, based on the calculated value of the determination index, it may be determined whether the subject is in an apnea state during the period covered by the time window.

[0060] FIG. 5A and FIG. 5B are diagrams schematically showing an example of the change in the value of Doppler data. The horizontal axis represents the date and time t, and the vertical axis represents the value x of the Doppler data. It is assumed that the subject is not in an apnea state during the period P1 and is in an apnea state during the period P2.

[0061] The situation shown in FIG. 5B has a smaller amplitude of Doppler data than the situation shown in FIG. 5A. For example, when the subject is at a location far from the Doppler sensor 12, a situation where the amplitude of the Doppler data becomes small as shown in FIG. 5B occurs.

[0062] Here, for example, when a situation where the amplitude of the Doppler data is smaller than a predetermined threshold th1 (a situation where the value of the Doppler data is greater than -th1 and smaller than th1) continues for a predetermined time or more, it may be considered to determine that the subject is in an apnea state.

[0063] In this determination, as shown in FIG. 5A, when the value of the Doppler data in the period P2 is greater than the threshold th1, although the subject is in an apnea state in the period P2, it is determined that the subject is not in an apnea state. Also, as shown in FIG. 5B, when the value of the Doppler data in the period P1 is smaller than the threshold th1, although the subject is not in an apnea state in the period P1, it is determined that the subject is in an apnea state.

[0064] Thus, in the method of determining whether the subject is in an apnea state based on the amplitude of the Doppler data, it is not possible to stably determine whether the subject is in an apnea state.

[0065] FIG. 6A and FIG. 6B are diagrams schematically showing an example of changes in the value of a determination index based on the change rate of the value of Doppler data at each of a plurality of consecutive time points described above. The horizontal axis represents the date and time t, and the vertical axis represents the value y of the determination index described above. And, similar to FIGS. 5A and 5B, it is assumed that the subject is not in an apnea state during period P1 and the subject is in an apnea state during period P2. Also, it is assumed that the situation shown in FIG. 6B has a smaller amplitude of Doppler data than the situation shown in FIG. 6A.

[0066] As shown in FIGS. 6A and 6B, when the subject is in an apnea state, the value y of the determination index described above becomes almost zero regardless of the magnitude of the amplitude of the Doppler data in a situation where the subject is not in an apnea state.

[0067] Therefore, according to the present embodiment, regardless of the amplitude of the Doppler data in period P1, as shown in FIGS. 6A and 6B, a predetermined threshold value th2 is appropriately set, and whether the subject is in an apnea state is determined based on whether the threshold value th2 is exceeded. Thus, it is possible to stably determine whether the subject is in an apnea state regardless of the magnitude of the amplitude of the Doppler data in period P1.

[0068] Note that the present invention is not limited to the above-described embodiment, and various modifications can be made.

[0069] For example, the present invention may be used to determine that the subject has bradyarrhythmia.

[0070] In this case, the microwave emitted from the Doppler sensor 12 may be reflected by the heart of the subject sleeping in the bed 14, and the Doppler sensor 12 may receive the reflected wave. Then, the signal processing device 10 may generate the heart rate of the subject based on the Doppler signal output from the Doppler sensor 12.

[0071] Then, by a method similar to the method for determining whether the subject is in an apnea state described above, it may be determined whether the subject has bradyarrhythmia. In the determination of whether the subject has bradyarrhythmia, a time window different from the time window used in the determination of whether the subject is in an apnea state (for example, a time window with a different size) may be used. Also in this case, the integrated value of the spectrum obtained by performing a short-time Fourier transform (STFFT) on the value of the Doppler data used in the determination of whether the subject is in an apnea state may be used as the value of the Doppler data acquired by the Doppler data acquisition unit 20 in the determination of whether the subject has bradyarrhythmia. The determination that the subject has bradyarrhythmia in this case corresponds to an example of the determination that the action that the subject should have does not appear. By doing so, it becomes possible to stably determine whether the subject has bradyarrhythmia regardless of the amplitude of the Doppler data.

[0072] As described above, according to the present embodiment, it becomes possible to stably determine that the action that the subject should have does not appear (for example, the subject is in an apnea state, the subject has bradyarrhythmia, etc.) using the Doppler sensor 12.

[0073] In addition, in the present embodiment, it may be determined whether or not the subject is in an apnea state, and it may also be determined whether or not the subject has bradyarrhythmia. Further, in the present embodiment, when it is determined that the subject is in an apnea state, it may be determined whether or not the subject has bradyarrhythmia by using the Doppler data used for the determination of whether or not the subject is in an apnea state. In this case, the integrated value of the spectrum obtained by performing a short-time Fourier transform (STFFT) on the value of the Doppler data used for the determination of whether or not the subject is in an apnea state may be used as the value of the Doppler data acquired by the Doppler data acquisition unit 20 in the determination of whether or not the subject has bradyarrhythmia. Since there is a high tendency that a subject with apnea syndrome may also have bradyarrhythmia, by doing so, it becomes possible to efficiently determine that the subject has bradyarrhythmia.

Explanation of Signs

[0074] 1 Apnea state determination system, 10 Signal processing device, 12 Doppler sensor, 14 Bed, 20 Doppler data acquisition unit, 22 Change rate calculation unit, 24 Determination index calculation unit, 26 Apnea state determination unit.

Claims

1. an acquisition means for repeatedly acquiring Doppler data indicating a measurement result by a Doppler sensor provided facing the subject; a rate of change calculation means for calculating a rate of change of the value of the Doppler data at each of a plurality of consecutive time points; a non-motion state determination means for determining whether the subject is not performing a desired motion based on the rate of change at each of the plurality of time points; A non-operating state determination system including:

2. The motionless state determination system according to claim 1, a time window change rate total calculation means for calculating, for each of a plurality of time windows each including a first predetermined number of consecutive time points, a total of absolute values ​​of the change rates at each of the first predetermined number of time points included in the time window as a time window change rate total corresponding to the time window, The motionless state determination means determines that the subject is not exhibiting an expected movement based on the average, sum, or variance of the time window change rate sums corresponding to each of a second predetermined number of consecutive time windows.

3. The motionless state determination system according to claim 1, The motionless state determination means determines that the subject is not exhibiting an expected movement based on the average, sum, or variance of the absolute values ​​of the rate of change at each of the multiple time points.

4. The motionless state determination system according to claim 1, The motionless state determination means determines that the subject is not exhibiting an expected movement based on the variance of the rate of change at each of the multiple time points.

5. The motionless state determination system according to claim 1, the change rate calculation means calculates a change rate of the value of the Doppler data at each of the plurality of time points for each of the plurality of Doppler sensors; The motionless state determination means determines whether the subject is not exhibiting an expected movement based on the rate of change calculated for each of the plurality of Doppler sensors.

6. 6. The motionless state determination system according to claim 5, an individual time window change rate sum calculation means for calculating, for each of a plurality of time windows each including a first predetermined number of consecutive time points for each of the plurality of Doppler sensors, a sum of absolute values ​​of the change rates at each of the first predetermined number of time points included in the time window as an individual time window change rate sum corresponding to the time window; a time window change rate total calculation means for calculating, for each of the plurality of time windows, a sum of the individual time window change rate totals corresponding to the time window of each of the plurality of Doppler sensors as a time window change rate total corresponding to the time window, The motionless state determination means determines that the subject is not exhibiting an expected movement based on the average, sum, or variance of the time window change rate sums corresponding to each of a second predetermined number of consecutive time windows.

7. 6. The motionless state determination system according to claim 5, a time-point change rate total calculation means for calculating, for each of the plurality of time points, a sum of absolute values ​​of the change rates of the respective Doppler sensors as a time-point change rate total corresponding to that time point; and a time window change rate total calculation means for calculating, for each of a plurality of time windows each including a first predetermined number of consecutive time points, a sum of the time point change rate totals at each of the first predetermined number of time points included in the time window as a time window change rate total corresponding to the time window, The motionless state determination means determines that the subject is not exhibiting an expected movement based on the average, sum, or variance of the time window change rate sums corresponding to each of a second predetermined number of consecutive time windows.

8. 6. The motionless state determination system according to claim 5, a time-point change rate total calculation means for calculating, for each of the plurality of time points, a sum of absolute values ​​of the change rates of the respective plurality of Doppler sensors as a time-point change rate total corresponding to the time point; The motionless state determination means determines that the subject is not exhibiting an expected movement based on the average, sum, or variance of the total time-point change rates corresponding to each of the multiple time points.

9. 6. The motionless state determination system according to claim 5, a variance calculation means for calculating a variance of a rate of change of the value of the Doppler data at each of the plurality of time points for each of the plurality of Doppler sensors; The motionless state determination means determines that the subject is not exhibiting an expected movement based on the average or sum of the variances of the change rates in each of the multiple Doppler sensors.

10. The motionless state determination system according to claim 1, The motionless state determination means determines whether the subject is in an apnea state.

11. The motionless state determination system according to claim 1, The motionless state determination means determines whether the subject has bradycardia arrhythmia.

12. Repeatedly acquiring Doppler data indicating a measurement result by a Doppler sensor provided facing the subject; calculating a rate of change of the value of the Doppler data at each of a plurality of consecutive time points; determining whether the subject is not performing an expected movement based on the rate of change at each of the plurality of time points; A method for determining a motionless state, comprising:

13. Repeatedly acquiring Doppler data indicating a measurement result by a Doppler sensor provided facing the subject; calculating a rate of change of the value of the Doppler data at each of a plurality of consecutive time points; determining whether the subject is not performing an expected movement based on the rate of change at each of the plurality of time points; A program for causing a computer to execute the following.

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