WO2018167897A1 - Biometric information detection device and biometric information detection program - Google Patents

Biometric information detection device and biometric information detection program Download PDF

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Publication number
WO2018167897A1
WO2018167897A1 PCT/JP2017/010538 JP2017010538W WO2018167897A1 WO 2018167897 A1 WO2018167897 A1 WO 2018167897A1 JP 2017010538 W JP2017010538 W JP 2017010538W WO 2018167897 A1 WO2018167897 A1 WO 2018167897A1
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Prior art keywords
antenna
characteristic
information detection
biological information
loss
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PCT/JP2017/010538
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French (fr)
Japanese (ja)
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仲尾圭市
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富士通株式会社
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Priority to PCT/JP2017/010538 priority Critical patent/WO2018167897A1/en
Publication of WO2018167897A1 publication Critical patent/WO2018167897A1/en

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    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/02—Detecting, measuring or recording pulse, heart rate, blood pressure or blood flow; Combined pulse/heart-rate/blood pressure determination; Evaluating a cardiovascular condition not otherwise provided for, e.g. using combinations of techniques provided for in this group with electrocardiography or electroauscultation; Heart catheters for measuring blood pressure
    • A61B5/024—Detecting, measuring or recording pulse rate or heart rate
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/08—Detecting, measuring or recording devices for evaluating the respiratory organs
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/103—Detecting, measuring or recording devices for testing the shape, pattern, colour, size or movement of the body or parts thereof, for diagnostic purposes
    • A61B5/11—Measuring movement of the entire body or parts thereof, e.g. head or hand tremor, mobility of a limb

Definitions

  • the present invention relates to a biological information detection apparatus and a biological information detection program.
  • JP 2013-153783 A Japanese Patent Laying-Open No. 2015-116473
  • an object of the first aspect of the present disclosure is to provide a biological information detection apparatus that can realize detection of biological information (for example, at least one of heartbeat and respiration) that is not easily influenced by the movement of the living body. It is in.
  • One embodiment is a biological information detection apparatus in a biological information detection system having a first antenna and a second antenna provided on the opposite side of the first antenna across the living body, An electromagnetic wave output unit for outputting an electromagnetic wave to the first antenna; a first characteristic of a reflected wave of the electromagnetic wave received by the first antenna; and a second characteristic of the electromagnetic wave received by the second antenna. And a biological information detector that detects at least one of heartbeat and respiration of the living body based on characteristics.
  • a biological information detection device that can realize detection of biological information (for example, at least one of heartbeat and respiration) that is not easily influenced by the movement of the living body.
  • FIG. 1 is a diagram illustrating an overall configuration of a biological information detection system 10.
  • FIG. 4 is a diagram for explaining the operation of the biological information detection system 10.
  • FIG. (A) an example of a waveform representing the reflection characteristic S 11, an example of a waveform representing the (b) passing characteristic S 21, an example of a waveform representing the (c) loss PL.
  • This is an example in which the biological information detection system 10 is applied to a vehicle (not shown).
  • It is a functional block diagram of a biological information detection device (on-vehicle device).
  • 4 is a flowchart for explaining an initial calibration process of the biological information detection system 10.
  • FIG. 7 is a flowchart for explaining the biological information detection process of the biological information detection system 10.
  • FIG. 1 is a diagram illustrating an overall configuration of the biological information detection system 10.
  • the biological information detection system 10 includes a first antenna ANT1, a second antenna ANT2, a biological information detection device 20, and the like.
  • the first antenna ANT1 and the second antenna ANT2 are arranged so as to sandwich the measurement object 30 (for example, a driver of an automobile; hereinafter also referred to as a driver 30).
  • the measurement object 30 corresponds to the living body of the present invention.
  • the number of antennas is not limited to the first antenna ANT1 and the second antenna ANT2, but three or more antennas such as the first antenna ANT1, the second antenna ANT2, the third antenna ANT3,. An antenna may be used.
  • FIG. 2 is a diagram for explaining the operation of the biological information detection system 10.
  • the first antenna ANT1 transmits a high frequency signal (transmitted wave) generated by the high frequency signal generator 21.
  • the high frequency signal corresponds to the electromagnetic wave of the present invention.
  • the first antenna ANT1 receives the reflected wave reflected by the measurement target 30.
  • the second antenna ANT2 receives the passing wave that has passed through the measurement object 30.
  • the third antenna ANT3 When three or more antennas are used, the third antenna ANT3... Also receives a passing wave that has passed through the measurement target 30.
  • the biological information detection apparatus 20 calculates the reflection characteristics based on the reflected wave received by the first antenna ANT1.
  • the reflection characteristic corresponds to the first characteristic of the present invention.
  • the biological information detection apparatus 20 calculates a passing characteristic based on the passing wave received by the second antenna ANT2.
  • the pass characteristic corresponds to the second characteristic of the present invention.
  • the reflection characteristic and the transmission characteristic (S parameter) between the first antenna ANT1 and the second antenna ANT2 are expressed by the following equations: 1 and 2 can be calculated.
  • Reflection characteristic S 11 b 1 / a 1 (Expression 1)
  • Passing characteristic S 21 b 2 / a 1 (Expression 2)
  • b 1 is the amplitude of the reflected wave
  • b 2 is the amplitude of the passing wave
  • a 1 is the amplitude of the transmitted wave.
  • FIG. 3 (a) is an example of a waveform representing the reflection characteristic S 11
  • FIG. 3 (b) is a waveform example representing the pass characteristic S 21.
  • Equation 3 indicates that if the reflection characteristic S 11 is large (small), the pass characteristic S 21 becomes small (large), and that the sum of the power of the reflected wave and the pass wave does not exceed the power of the transmission wave. To express.
  • the loss PL of the measurement system including the antennas ANT1 and ANT2 and the measurement target 30 is defined by the following equation (4).
  • Loss PL 1 ⁇ (
  • the loss PL is the difference between the power of the transmission radio wave and the reception radio wave.
  • the above equation 4 determines the loss PL from the difference in amplitude between the transmitted radio wave and the received radio wave.
  • FIG. 3C shows an example of a waveform representing the loss PL.
  • body movement and vibration are changes in position. Even if the reflected wave or the passing wave changes due to the measurement object 30 moving relative to the antennas ANT1 and ANT2 due to body movement and vibration, the reflection characteristic S 11 and the passage characteristic S 21 only change, so that the change in loss PL due to body movement and vibration is relatively small.
  • the body movement here refers to a relatively small body movement such as a body movement when the driver 30 operates the handle.
  • the vibration referred to here is a relatively small vibration such as, for example, a rotation of an automobile engine or a vibration generated when traveling on a general road.
  • the movement of the measurement target 30 relative to the antennas ANT1 and ANT2 is a movement in a linear direction (front-rear direction) connecting the first antenna ANT1 and the second antenna ANT2, and a direction perpendicular to the straight line. This is either or both of the movements (for example, in the left-right direction).
  • the dielectric constant of the measurement object 30 locally changes due to heartbeat and respiration, the change in loss PL due to heartbeat and respiration is relatively large.
  • the change in dielectric constant, reflection characteristic S 11 or pass characteristic S 21 is changed. That is, changes in blood flow due to pulsation of the heart and movements of the lungs due to respiration are accompanied by local changes in dielectric constant.
  • the high frequency passing through the portion having a relatively high dielectric constant is greatly attenuated (that is, the amplitude of the passing wave is reduced) compared to the high frequency passing through the portion having a relatively low dielectric constant.
  • the loss (time series data) changes in time series with heartbeat and respiration, and includes a heartbeat signal and a respiration signal.
  • the loss includes a heartbeat signal and a respiration signal from which the influence of body motion and vibration has been removed.
  • This loss (time series data) has the following advantages.
  • the change in loss PL caused by body movement or vibration is relatively small (for example, smaller than the initial value (threshold) described later), the loss caused by the body movement or vibration is not performed without using another filter. It is possible to obtain a state in which a change in PL is removed (noise canceling effect). This is because the change in loss PL caused by relatively small body movements and vibrations is smaller than the change in loss PL caused by heartbeats and breathing, so the heartbeat signal and respiration signal are lost due to the body movements and vibrations. This is because it is not (or hardly) affected by the change in PL.
  • the change in loss PL due to relatively large body movements and vibrations is larger than the change in loss PL due to heartbeat and respiration. .
  • the body movement or vibration is relatively large (for example, when it is larger than an initial value (threshold) described later), the measurement system itself changes greatly.
  • a threshold value (initial value) is provided, and when the threshold value is exceeded, a filtering process described later is performed, so that changes in loss PL caused by the body movement and vibration can be removed.
  • Living body information detection apparatus 20 based on the reflection characteristic S 11 calculated above and the transmission characteristic S 21, to detect the heart rate and respiration of the measurement target 30.
  • the biological information detection apparatus 20 based on the reflection characteristic S 11 calculated above and the transmission characteristic S 21, loss PL (power measurement system comprising a respective antenna ANT1, ANT2 and measured 30 (Scattering rate) is calculated.
  • loss PL power measurement system comprising a respective antenna ANT1, ANT2 and measured 30 (Scattering rate) is calculated.
  • the biological information detection apparatus 20 calculates the loss PL using the above equation 4.
  • the biological information detection apparatus 20 extracts a heartbeat signal and a respiration signal from the calculated loss PL (time series data). Specifically, a heartbeat signal and a respiration signal are extracted by performing a filtering process such as a bandpass filter.
  • the biological information detection apparatus 20 detects (estimates) the heart rate and the respiration rate using a known means.
  • Known methods include a method of selecting a peak frequency using a fast Fourier transform (FFT), a method of counting heartbeat signal peaks (respiration signal peaks), and the like.
  • FFT fast Fourier transform
  • the heartbeat signal and the respiration signal and noise caused by body movement and vibration are caused by the body movement and vibration. It is difficult to separate the noise due to the change in the relative positional relationship with ANT2.
  • loss PL time series data
  • noise caused by relatively small body movements and vibrations can be removed, and heart rate (number) and respiration (number) Can be estimated (detected) with high accuracy.
  • the loss PL changes to remove the relatively small motion (relatively small body movement and noise caused by vibration), losses PL It is possible to expect a kind of noise canceling effect of extracting a relatively large change (a relatively large heartbeat signal or respiration signal). As a result, noise caused by relatively small body movement and vibration can be removed without using another filter, and heartbeat and respiration can be accurately estimated.
  • the loss PL is This is because the property of taking a constant value is used.
  • FIG. 4 shows an example in which the biological information detection system 10 is applied to a vehicle (not shown).
  • the biological information detection device 20 is referred to as the in-vehicle device 20.
  • the in-vehicle device 20 (mainly CPU 25) corresponds to the computer of the present invention.
  • the in-vehicle device 20 includes a high-frequency signal generator 21, a bandpass filter 22, a coupler 23, a signal receiver 24 (hereinafter also referred to as a digital signal processing circuit 24), a CPU 25 (Central Processing Unit), a memory. 26 etc.
  • the first antenna ANT1 is generated by the high-frequency signal generator 21, passes through the band-pass filter 22, and further transmits a high-frequency signal (transmission wave) via the coupler 23.
  • the second antenna ANT2 is provided on the opposite side of the first antenna ANT1 with the driver 30 interposed therebetween.
  • the antennas ANT1 and ANT2 are arranged so that the driver 30 seated in a standard posture (stationary posture) on the driver's seat is positioned on a straight line connecting the first antenna ANT1 and the second antenna ANT2. Specifically, each of the antennas ANT1 and ANT2 passes a part of the high frequency transmitted from the first antenna ANT1 through the heart and lungs of the driver 30 seated in a standard posture in the driver's seat, and the high frequency that has passed therethrough. It arrange
  • the first antenna ANT1 is arranged inside the driver's seat, and the second antenna ANT2 is arranged inside the dashboard in front of the driver's seat.
  • the second antenna ANT2 may be arranged inside the driver's seat, and the first antenna ANT1 may be arranged inside the dashboard in front of the driver's seat.
  • the antennas ANT1 and ANT2 are connected to the in-vehicle device 20 through wiring. Signals transmitted and received by the respective antennas ANT1 and ANT2 are transmitted to the in-vehicle device 20 through wiring.
  • the high-frequency signal generator 21 generates frequency components that are partly reflected by the driver 30 and received by the first antenna ANT1, and the other part passes through the driver 30 and is received by the second antenna ANT2.
  • a high-frequency signal generator that generates a high-frequency signal including.
  • the band-pass filter 22 Only a specific frequency component of the high-frequency signal generated by the high-frequency signal generator 21 passes through the band-pass filter 22 and is input to the digital signal processing circuit 24 and the antenna ANT1. Part of the specific frequency component (corresponding to the electromagnetic wave of the present invention) is reflected by the driver 30 and received by the first antenna ANT1, and the other part passes through the driver 30 and passes through the second antenna ANT2.
  • the frequency component is selected from the range of several kHz to several GHz.
  • the high-frequency signal generator 21 and the band-pass filter 22 correspond to the electromagnetic wave output unit of the present invention.
  • the coupler 23 is a directional coupler (directional coupler) that can separate and extract the traveling wave of the high-frequency signal that has passed through the bandpass filter 22 and the received signal received by the first antenna ANT1.
  • the reception signal extracted by the coupler 23 is input to the digital signal processing circuit 24.
  • the reception signal received by the second antenna ANT2 is also input to the digital signal processing circuit 24.
  • CPU 25 is responsible for the overall operation of the in-vehicle device 20.
  • the memory 26 is, for example, a RAM (Random Access Memory).
  • FIG. 5 is a functional block diagram of the biological information detection apparatus (on-vehicle apparatus).
  • the digital signal processing circuit 24 includes an A / D conversion unit 24a, a reflection characteristic calculation unit 24b, a transmission characteristic calculation unit 24c, a biological information detection unit 24d (a loss calculation unit 24d1, a biological information extraction unit 24d2, A heart rate / respiration rate detector 24d3).
  • the A / D converter 24a receives three signals input thereto, that is, a high-frequency signal that has passed through the bandpass filter 22, and a received signal that is received by the first antenna ANT1 and separated by the coupler 23 (A signal after detection) and A / D conversion (sampling) of the received signal (signal after detection) received by the second antenna ANT2.
  • the sampling frequency is a frequency considered so that a heartbeat signal and a respiration signal can be extracted.
  • Reflection characteristic calculating unit 24b based on the reflected waves first antenna ANT1 is received, calculates the reflection characteristic S 11. Specifically, the reflection characteristic calculating unit 24b, using the above equation 1, for each sampling period, and calculates the reflection characteristic S 11.
  • the reflection characteristic calculation unit 24b corresponds to the first characteristic calculation unit of the present invention.
  • Pass characteristic calculation unit 24c based on the passage waves second antenna ANT2 is received, calculates the pass characteristics S 21. Specifically, pass characteristic calculation unit 24c, using the above equation 2, for each sampling period, and calculates the pass characteristics S 21.
  • the pass characteristic calculation unit 24c corresponds to the second characteristic calculation unit of the present invention.
  • the biological information detection unit 24d includes a loss calculation unit 24d1, a biological information extraction unit 24d2, and a heartbeat / respiration rate detection unit 24d3.
  • Loss calculation unit 24d1 has a reflection characteristic S 11 that the reflection characteristics calculating unit 24b is calculated, the pass characteristic S 21 that pass characteristic calculation unit 24c is calculated, on the basis of the driver 30 heartbeat signal (waveform), and respiratory
  • the loss PL including the signal (waveform) is calculated.
  • the loss calculation unit 24d1 calculates the loss PL for each sampling period using the above equation 4, and stores the loss PL in the memory 26 as time series data.
  • the biological information extraction unit 24d2 performs a filtering process such as a band-pass filter on the loss PL (time series data) stored in the memory 26, so that the loss PL (time series data) stored in the memory 26 is used.
  • a heartbeat signal and a respiration signal are extracted (detected). At that time, a heartbeat filter and a breathing filter are used.
  • the heartbeat filter is a filter (for example, a bandpass filter) that is considered so that a heartbeat signal included in the calculated loss PL (time-series data) can be extracted.
  • the respiration filter is a filter (for example, a bandpass filter) that is considered so that a respiration signal included in the calculated loss PL (time-series data) can be extracted.
  • the heart rate / respiration rate detection unit 24d3 detects (estimates) the heart rate and the respiration rate from the heart rate signal and the respiration signal extracted by the biological information extraction unit 24d2 using known means such as fast Fourier transform.
  • the CPU 25 functions as a comparison unit 25a and a noise removal unit 25b by executing a predetermined program read into the memory 26.
  • the comparison unit 25a compares the loss PL calculated by the loss calculation unit 24d1 with a threshold value.
  • the noise removing unit 25b removes a noise signal from the loss PL (time series data) by performing a filtering process such as a band pass filter.
  • FIG. 6 is a flowchart for explaining an initial calibration process of the biological information detection system 10.
  • the driver 30 sits in the driver's seat in a standard posture (stationary posture), and the relative positional relationship of the driver 30 with respect to the antennas ANT1 and ANT2 does not change (or hardly changes). Executed in state.
  • the following processing is realized mainly by the CPU 25 executing a predetermined program (for example, a biological information detection program) read into the memory 26.
  • a predetermined program for example, a biological information detection program
  • the high frequency signal generator 21 generates a high frequency signal for a certain period (for example, 30 seconds) (step S10). Only an arbitrary frequency component of the high frequency signal generated by the high frequency signal generator 21 passes through the band pass filter 22 and is input to the digital signal processing circuit 24 and the first antenna ANT1. The first antenna ANT1 transmits a high frequency signal (radio wave) input thereto.
  • the first antenna ANT1 receives the reflected wave reflected by the driver 30, and the second antenna ANT2 receives the passing wave that has passed through the driver 30 (step S11).
  • the received signal received by the first antenna ANT1 is extracted by the coupler 23 and input to the digital signal processing circuit 24.
  • the reception signal received by the second antenna ANT2 is also input to the digital signal processing circuit 24.
  • the detection unit detects the reflected wave (reception signal) and the passing wave (reception signal) received in step S11 (step S12).
  • the detection unit is realized by, for example, a predetermined circuit or by the CPU 25 executing a predetermined program.
  • the A / D conversion unit 24a receives the high-frequency signal that has passed through the band-pass filter 22, the reception signal received by the first antenna ANT1 and separated by the coupler 23 (the signal after detection in step S12), and The received signal (the signal after the detection in step S12) received by the second antenna ANT2 is sampled.
  • the reflection characteristic calculation unit 24b by using the above equation 1, for each sampling period, and calculates the reflection characteristic S 11, and, passing characteristic calculation unit 24c by using the above equation 2, for each sampling period, passing calculating a characteristic S 21 (step S14).
  • the loss calculation unit 24d1 calculates the loss PL for each sampling period using the above equation 4 (step S15).
  • the calculated loss PL is stored as an initial value (threshold value) in the memory 26 (step S16).
  • the calculated loss PL is stored as average value data (or time series data). Note that the calculated loss PL may be stored in the memory 26 as an initial value obtained by, for example, ⁇ 50% of the loss PL.
  • FIG. 7 is a flowchart for explaining the biological information detection process of the biological information detection system 10.
  • the biological information detection process is executed, for example, in a state where the driver 30 sitting in a standard posture on the driver's seat is driving.
  • the following processing is realized mainly by the CPU 25 executing a predetermined program (for example, a biological information detection program) read into the memory 26.
  • a predetermined program for example, a biological information detection program
  • the high frequency signal generator 21 generates a high frequency signal (step S10A). Only an arbitrary frequency component of the high frequency signal generated by the high frequency signal generator 21 passes through the band pass filter 22 and is input to the digital signal processing circuit 24 and the first antenna ANT1.
  • the first antenna ANT1 transmits a high frequency signal (radio wave) input thereto.
  • the first antenna ANT1 receives the reflected wave reflected by the driver 30, and the second antenna ANT2 receives the passing wave that has passed through the driver 30 (step S11A).
  • the received signal received by the first antenna ANT1 is extracted by the coupler 23 and input to the digital signal processing circuit 24.
  • the reception signal received by the second antenna ANT2 is also input to the digital signal processing circuit 24.
  • the detection unit detects the reflected wave (reception signal) and the passing wave (reception signal) received in step S11A (step S12A).
  • the detection unit is realized by, for example, a predetermined circuit or by the CPU 25 executing a predetermined program.
  • the A / D conversion unit 24a receives the high-frequency signal that has passed through the band-pass filter 22, the reception signal received by the first antenna ANT1 and separated by the coupler 23 (the signal after detection in step S12), and The received signal (the signal after the detection in step S12) received by the second antenna ANT2 is sampled.
  • the reflection characteristic calculation unit 24b by using the above equation 1, for each sampling period, and calculates the reflection characteristic S 11, and, passing characteristic calculation unit 24c by using the above equation 2, for each sampling period, passing calculating a characteristic S 21 (step S14A).
  • the loss calculation unit 24d1 calculates the loss PL for each sampling period using the above equation 4 (step S15A).
  • the comparison unit 25a compares the loss PL calculated by the loss calculation unit 24d1 with the initial value (threshold value) stored in the memory 26 in step S16 for each sampling period (step S20).
  • the noise removing unit 25b performs a filtering process to remove the noise signal from the loss PL (step S21).
  • the loss PL from which the noise signal has been removed is stored in the memory 26 (step S22).
  • step S20 if the loss PL is smaller than the initial value (loss ⁇ initial value) as a result of the comparison in step S20, the filtering process is not performed, and the loss PL calculated in step S15A is stored in the memory 26 (step S22).
  • steps 14A to S23 are repeatedly executed until the sampling period is completed (step S23: No). Thereby, the loss PL (time-series data) from which the noise signal is removed is stored in the memory 26.
  • step S23 when the sampling cycle is ended (step S23: Yes), the biological information extraction unit 24d2 performs a filtering process, so that a heartbeat signal (waveform) and a loss PL (time-series data) stored in the memory 26 are obtained. A breathing (waveform) signal is extracted (detected) (step S24).
  • the heart rate / respiration rate detection unit 24d3 detects (estimates) the heart rate and respiration rate from the heart rate signal and respiration signal extracted by the biological information extraction unit 24d2.
  • the biological information detection apparatus 20 and the biological information detection program that can realize detection of biological information (for example, heartbeat and respiration) that is not easily influenced by the movement of the driver 30.
  • the movement of the driver 30 here refers to a movement in a linear direction (front-rear direction) connecting the first antenna ANT1 and the second antenna ANT2, and a movement in a direction perpendicular to the straight line (for example, left-right direction). Either or both.
  • the measurement target 30 is a driver of an automobile and the biological information detection device 20 is the in-vehicle device 20 mounted on the vehicle has been described, but the present invention is not limited thereto.
  • the measurement target 30 may be a person sleeping in a bed or other people, and the biological information detection device 20 may be provided in the bed, in the vicinity thereof, or elsewhere.
  • the said embodiment demonstrated the example which extracts the signal (waveform) of a heartbeat and the signal of a respiration (waveform) (step S24), and detects (estimates) a heart rate and a respiration rate, it does not restrict to this. Absent. For example, at least one of a heartbeat signal (waveform) and a respiration (waveform) signal may be extracted. Further, at least one of the heart rate and the respiratory rate may be detected (estimated).
  • SYMBOLS 10 Biological information detection system, 20 ... Biological information detection apparatus (vehicle equipment), 21 ... High frequency signal generator, 22 ... Band pass filter, 23 ... Coupler, 24 ... Signal receiver (digital signal processing circuit), 24a ... A / D conversion unit, 24b ... reflection characteristic calculation unit, 24c ... passage characteristic calculation unit, 24d ... biological information detection unit, 24d1 ... loss calculation unit, 24d2 ... biological information extraction unit, 24d3 ... heart rate / respiration rate detection unit, 25 ... CPU, 25a ... comparing unit, 25b ... noise removing unit, 26 ... memory, 30 ... measurement object (driver), ANT1 ... first antenna, ANT2 ... second antenna, PL ... loss, S 11 ... reflection characteristics, S 21 ... Passing characteristics

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Abstract

A biometric information detection device in a biometric information detection system having a first antenna and a second antenna that is disposed on the opposite side of a living body from the first antenna, the biometric information detection device being provided with an electromagnetic wave output unit that causes the first antenna to output electromagnetic waves, and a biometric information detection unit that detects either heartbeat and/or respiration of the living body on the basis of a first characteristic of reflected waves of the electromagnetic waves received by the first antenna and a second characteristic of the electromagnetic waves received by the second antenna. The present invention enables detection of biometric information (for example, heartbeat and/or respiration) in a manner not liable to be affected by motion of the living body.

Description

生体情報検出装置、及び、生体情報検出プログラムBiological information detection apparatus and biological information detection program
　本発明は、生体情報検出装置、及び、生体情報検出プログラムに関する。 The present invention relates to a biological information detection apparatus and a biological information detection program.
　従来、生体（例えば、人）に電波（マイクロ波や高周波）を送信し、生体からの反射波や生体を通過した通過波に基づいて、呼吸や心拍を推定する技術が提案されている（例えば、特許文献１、２参照）。 Conventionally, a technique for transmitting a radio wave (microwave or high frequency) to a living body (for example, a person) and estimating respiration or a heartbeat based on a reflected wave from the living body or a passing wave that has passed through the living body has been proposed (for example, Patent Documents 1 and 2).
特開２０１３－１５３７８３号公報JP 2013-153783 A 特開２０１５－１１６４７３号公報Japanese Patent Laying-Open No. 2015-116473
　しかしながら、上記従来技術においては、反射波や通過波は、生体がアンテナに対して相対的に動いた場合（例えば、体動や振動に起因して動いた場合）、その動きに起因するノイズを含み、原理的にそのノイズを除去できないため、心拍や呼吸を精度よく検出するのが難しいという課題がある。 However, in the above prior art, when the living body moves relative to the antenna (for example, when the living body moves due to body movement or vibration), the noise caused by the movement of the reflected wave or the passing wave is reduced. In addition, since the noise cannot be removed in principle, there is a problem that it is difficult to accurately detect heartbeat and respiration.
　そこで、本開示の第１の側面の目的は、生体の動きの影響を受けづらい生体情報（例えば、心拍及び呼吸のうち少なくとも一方）の検出を実現することができる生体情報検出装置を提供することにある。 Therefore, an object of the first aspect of the present disclosure is to provide a biological information detection apparatus that can realize detection of biological information (for example, at least one of heartbeat and respiration) that is not easily influenced by the movement of the living body. It is in.
　一つの実施の形態は、第一のアンテナと、生体を挟んで前記第一のアンテナの反対側に備えられた第二のアンテナと、を有する生体情報検出システムにおける生体情報検出装置であって、前記第一のアンテナに電磁波を出力させる電磁波出力部と、前記第一のアンテナで受信された前記電磁波の反射波の第一の特性と前記第二のアンテナで受信された前記電磁波の第二の特性とに基づいて、前記生体の心拍及び呼吸のうち少なくとも一方を検出する生体情報検出部と、を備える生体情報検出装置である。 One embodiment is a biological information detection apparatus in a biological information detection system having a first antenna and a second antenna provided on the opposite side of the first antenna across the living body, An electromagnetic wave output unit for outputting an electromagnetic wave to the first antenna; a first characteristic of a reflected wave of the electromagnetic wave received by the first antenna; and a second characteristic of the electromagnetic wave received by the second antenna. And a biological information detector that detects at least one of heartbeat and respiration of the living body based on characteristics.
　一つの実施の形態によれば、生体の動きの影響を受けづらい生体情報（例えば、心拍及び呼吸のうち少なくとも一方）の検出を実現することができる生体情報検出装置を提供することができる。 According to one embodiment, it is possible to provide a biological information detection device that can realize detection of biological information (for example, at least one of heartbeat and respiration) that is not easily influenced by the movement of the living body.
生体情報検出システム１０の全体構成を示す図である。1 is a diagram illustrating an overall configuration of a biological information detection system 10. FIG. 生体情報検出システム１０の動作について説明するための図である。4 is a diagram for explaining the operation of the biological information detection system 10. FIG. （ａ）反射特性Ｓ１１を表す波形例、（ｂ）通過特性Ｓ２１を表す波形例、（ｃ）損失ＰＬを表す波形例である。(A) an example of a waveform representing the reflection characteristic S 11, an example of a waveform representing the (b) passing characteristic S 21, an example of a waveform representing the (c) loss PL. 生体情報検出システム１０を車両（図示せず）に適用した例である。This is an example in which the biological information detection system 10 is applied to a vehicle (not shown). 生体情報検出装置（車載装置）の機能ブロック図である。It is a functional block diagram of a biological information detection device (on-vehicle device). 生体情報検出システム１０の初期キャリブレーション処理を説明するためのフローチャートである。4 is a flowchart for explaining an initial calibration process of the biological information detection system 10. 図７は、生体情報検出システム１０の生体情報検出処理を説明するためのフローチャートである。FIG. 7 is a flowchart for explaining the biological information detection process of the biological information detection system 10.
　［生体情報検出システムの構成（概要）］
　図１は、生体情報検出システム１０の全体構成を示す図である。 [Configuration of biological information detection system (outline)]
FIG. 1 is a diagram illustrating an overall configuration of the biological information detection system 10.
　図１に示すように、生体情報検出システム１０は、第一のアンテナＡＮＴ１、第二のアンテナＡＮＴ２、生体情報検出装置２０等を備える。 As shown in FIG. 1, the biological information detection system 10 includes a first antenna ANT1, a second antenna ANT2, a biological information detection device 20, and the like.
　第一のアンテナＡＮＴ１、第二のアンテナＡＮＴ２は、測定対象３０（例えば、自動車のドライバー。以下、ドライバー３０ともいう）を挟み込むように配置される。測定対象３０が本発明の生体に相当する。なお、アンテナは、第一のアンテナＡＮＴ１、第二のアンテナＡＮＴ２の２つに限らず、第一のアンテナＡＮＴ１、第二のアンテナＡＮＴ２、第三のアンテナＡＮＴ３・・・のように３つ以上のアンテナを用いてもよい。 The first antenna ANT1 and the second antenna ANT2 are arranged so as to sandwich the measurement object 30 (for example, a driver of an automobile; hereinafter also referred to as a driver 30). The measurement object 30 corresponds to the living body of the present invention. The number of antennas is not limited to the first antenna ANT1 and the second antenna ANT2, but three or more antennas such as the first antenna ANT1, the second antenna ANT2, the third antenna ANT3,. An antenna may be used.
　［生体情報検出システムの動作（概要）］
　図２は、生体情報検出システム１０の動作について説明するための図である。 [Operation of biological information detection system (outline)]
FIG. 2 is a diagram for explaining the operation of the biological information detection system 10.
　第一のアンテナＡＮＴ１は、高周波信号発生器２１が発生した高周波信号（送信波）を送信する。高周波信号が本発明の電磁波に相当する。また、第一のアンテナＡＮＴ１は、測定対象３０で反射された反射波を受信する。一方、第二のアンテナＡＮＴ２は、測定対象３０を通過した通過波を受信する。なお、３つ以上のアンテナを用いた場合、第三のアンテナＡＮＴ３・・・も測定対象３０を通過した通過波を受信する。 The first antenna ANT1 transmits a high frequency signal (transmitted wave) generated by the high frequency signal generator 21. The high frequency signal corresponds to the electromagnetic wave of the present invention. The first antenna ANT1 receives the reflected wave reflected by the measurement target 30. On the other hand, the second antenna ANT2 receives the passing wave that has passed through the measurement object 30. When three or more antennas are used, the third antenna ANT3... Also receives a passing wave that has passed through the measurement target 30.
　生体情報検出装置２０は、第一のアンテナＡＮＴ１が受信した反射波に基づいて、反射特性を算出する。反射特性が本発明の第一の特性に相当する。また、生体情報検出装置２０は、第二のアンテナＡＮＴ２が受信した通過波に基づいて、通過特性を算出する。通過特性が本発明の第二の特性に相当する。 The biological information detection apparatus 20 calculates the reflection characteristics based on the reflected wave received by the first antenna ANT1. The reflection characteristic corresponds to the first characteristic of the present invention. In addition, the biological information detection apparatus 20 calculates a passing characteristic based on the passing wave received by the second antenna ANT2. The pass characteristic corresponds to the second characteristic of the present invention.
　各アンテナＡＮＴ１、ＡＮＴ２及び測定対象３０を含む測定系を、２端子対回路と考えると、第一のアンテナＡＮＴ１と第二のアンテナＡＮＴ２間の反射特性と通過特性（Ｓパラメータ）は、次の式１、式２で算出することができる。 Assuming that the measurement system including each antenna ANT1, ANT2 and measurement object 30 is a two-terminal pair circuit, the reflection characteristic and the transmission characteristic (S parameter) between the first antenna ANT1 and the second antenna ANT2 are expressed by the following equations: 1 and 2 can be calculated.
　反射特性Ｓ１１＝ｂ１／ａ１　・・・（式１）
　通過特性Ｓ２１＝ｂ２／ａ１　・・・（式２）
　但し、ｂ１は反射波の振幅、ｂ２は通過波の振幅、ａ１は送信波の振幅である。 Reflection characteristic S 11 = b 1 / a 1 (Expression 1)
Passing characteristic S 21 = b 2 / a 1 (Expression 2)
However, b 1 is the amplitude of the reflected wave, b 2 is the amplitude of the passing wave, and a 1 is the amplitude of the transmitted wave.
　図３（ａ）は反射特性Ｓ１１を表す波形例、図３（ｂ）は通過特性Ｓ２１を表す波形例である。 3 (a) is an example of a waveform representing the reflection characteristic S 11, FIG. 3 (b) is a waveform example representing the pass characteristic S 21.
　測定系に損失がある場合、反射特性Ｓ１１と通過特性Ｓ２１を用いると、次の式３が成り立つ。 If there is a loss in the measurement system, the use of the reflection characteristic S 11 and pass characteristic S 21, the following equation holds 3.
　|Ｓ１１|２＋|Ｓ２１|２≦１　・・・（式３）
　この式３は、反射特性Ｓ１１が大きい(小さい)と、通過特性Ｓ２１が小さく(大きく)なること、及び、反射波と通過波の電力の総和が送信波の電力を超えないこと、を表す。 | S 11 | 2 + | S 21 | 2 ≦ 1 (Formula 3)
Equation 3 indicates that if the reflection characteristic S 11 is large (small), the pass characteristic S 21 becomes small (large), and that the sum of the power of the reflected wave and the pass wave does not exceed the power of the transmission wave. To express.
　ここで、各アンテナＡＮＴ１、ＡＮＴ２及び測定対象３０を含む測定系の損失ＰＬを次の式４で定義する。 Here, the loss PL of the measurement system including the antennas ANT1 and ANT2 and the measurement target 30 is defined by the following equation (4).
　損失ＰＬ＝１－（|Ｓ１１|２＋|Ｓ２１|２）　・・・（式４）
　損失ＰＬは、送信電波と受信電波の電力の差である。送信電波と受信電波の振幅の差から損失ＰＬを求めるのが上記式４である。 Loss PL = 1− (| S 11 | 2 + | S 21 | 2 ) (Formula 4)
The loss PL is the difference between the power of the transmission radio wave and the reception radio wave. The above equation 4 determines the loss PL from the difference in amplitude between the transmitted radio wave and the received radio wave.
　図３（ｃ）は、損失ＰＬを表す波形例である。 FIG. 3C shows an example of a waveform representing the loss PL.
　このとき、測定対象３０に対する体動及び振動の影響と、心拍及び呼吸の影響について次のことが言える。 At this time, the following can be said about the influence of body movement and vibration on the measurement object 30, and the influence of heartbeat and respiration.
　すなわち、体動及び振動は位置の変化であり、体動及び振動によって測定対象３０が各アンテナＡＮＴ１、ＡＮＴ２に対して相対的に動くことで反射波や通過波が変化しても、反射特性Ｓ１１と通過特性Ｓ２１とのバランスが変化するのみであるため、体動及び振動に起因する損失ＰＬの変化は比較的小さい。ここでいう体動とは、例えば、ドライバー３０がハンドルを操作する際の体動のように比較的小さな体動のことである。また、ここでいう振動とは、例えば、自動車のエンジンの回転や一般道走行時に発生する振動のように比較的小さな振動のことである。また、ここでいう測定対象３０の各アンテナＡＮＴ１、ＡＮＴ２に対する動きとは、第一のアンテナＡＮＴ１と第二のアンテナＡＮＴ２とを結ぶ直線方向（前後方向）の動き、その直線に対して垂直の方向（例えば、左右方向）の動きのいずれか、又は、両方のことである。 That is, body movement and vibration are changes in position. Even if the reflected wave or the passing wave changes due to the measurement object 30 moving relative to the antennas ANT1 and ANT2 due to body movement and vibration, the reflection characteristic S 11 and the passage characteristic S 21 only change, so that the change in loss PL due to body movement and vibration is relatively small. The body movement here refers to a relatively small body movement such as a body movement when the driver 30 operates the handle. In addition, the vibration referred to here is a relatively small vibration such as, for example, a rotation of an automobile engine or a vibration generated when traveling on a general road. The movement of the measurement target 30 relative to the antennas ANT1 and ANT2 here is a movement in a linear direction (front-rear direction) connecting the first antenna ANT1 and the second antenna ANT2, and a direction perpendicular to the straight line. This is either or both of the movements (for example, in the left-right direction).
　一方、心拍及び呼吸によって測定対象３０の誘電率が局所的に変化するため、心拍及び呼吸による損失ＰＬの変化は比較的大きい。誘電率の変化により、反射特性Ｓ１１又は通過特性Ｓ２１が変化する。すなわち、心臓の脈動による血流の変化や、呼吸による肺が膨張する動きは、局所的な誘電率の変化を伴う。そして、誘電率が相対的に高い部分を通過する高周波は、誘電率が相対的に低い部分を通過する高周波と比べ、大きく減衰する（すなわち、通過波の振幅が小さくなる）。その結果、損失（時系列データ）は、心拍や呼吸に伴い時系列に変化し、心拍の信号及び呼吸の信号を含む。 On the other hand, since the dielectric constant of the measurement object 30 locally changes due to heartbeat and respiration, the change in loss PL due to heartbeat and respiration is relatively large. The change in dielectric constant, reflection characteristic S 11 or pass characteristic S 21 is changed. That is, changes in blood flow due to pulsation of the heart and movements of the lungs due to respiration are accompanied by local changes in dielectric constant. The high frequency passing through the portion having a relatively high dielectric constant is greatly attenuated (that is, the amplitude of the passing wave is reduced) compared to the high frequency passing through the portion having a relatively low dielectric constant. As a result, the loss (time series data) changes in time series with heartbeat and respiration, and includes a heartbeat signal and a respiration signal.
　以上のことから、損失（時系列データ）は、体動や振動の影響を除去した心拍の信号及び呼吸の信号を含むことが分かる。 From the above, it can be seen that the loss (time-series data) includes a heartbeat signal and a respiration signal from which the influence of body motion and vibration has been removed.
　この損失（時系列データ）によれば、次の利点がある。 This loss (time series data) has the following advantages.
　すなわち、体動や振動に起因する損失ＰＬの変化が比較的小さい場合（例えば、後述の初期値（閾値）より小さい場合）、別のフィルタを用いることなく、その体動や振動に起因する損失ＰＬの変化を除去した状態とすることができる（ノイズキャンセリング効果）。これは、比較的小さい体動や振動に起因する損失ＰＬの変化は心拍や呼吸に起因する損失ＰＬの変化より小さいため、心拍の信号や呼吸の信号は、その体動や振動に起因する損失ＰＬの変化の影響を受けない（又は、ほとんど受けない）ことによるものである。 That is, when the change in loss PL caused by body movement or vibration is relatively small (for example, smaller than the initial value (threshold) described later), the loss caused by the body movement or vibration is not performed without using another filter. It is possible to obtain a state in which a change in PL is removed (noise canceling effect). This is because the change in loss PL caused by relatively small body movements and vibrations is smaller than the change in loss PL caused by heartbeats and breathing, so the heartbeat signal and respiration signal are lost due to the body movements and vibrations. This is because it is not (or hardly) affected by the change in PL.
　なお、比較的大きな体動や振動（例えば、ドライバー３０が大きく動いたり、自動車が大きな段差に乗り上げた場合）に起因する損失ＰＬの変化は、心拍や呼吸に起因する損失ＰＬの変化より大きくなる。これは、体動や振動が比較的大きい場合（例えば、後述の初期値（閾値）より大きい場合）、測定系自体が大きく変化することによるものである。 Note that the change in loss PL due to relatively large body movements and vibrations (for example, when the driver 30 moves greatly or the car rides on a large step) is larger than the change in loss PL due to heartbeat and respiration. . This is because when the body movement or vibration is relatively large (for example, when it is larger than an initial value (threshold) described later), the measurement system itself changes greatly.
　このように体動や振動に起因する損失ＰＬの変化が比較的大きい場合、上記ノイズキャンセリング効果でその体動や振動に起因する損失ＰＬの変化を除去した状態とすることができない。この場合、後述のように閾値（初期値）を設け、その閾値を超えたときに、後述のフィルタリング処理を行うことで、その体動や振動に起因する損失ＰＬの変化を除去することができる。 Thus, when the change in loss PL caused by body movement or vibration is relatively large, the change in loss PL caused by body movement or vibration cannot be eliminated by the noise canceling effect. In this case, as described later, a threshold value (initial value) is provided, and when the threshold value is exceeded, a filtering process described later is performed, so that changes in loss PL caused by the body movement and vibration can be removed. .
　生体情報検出装置２０は、上記算出した反射特性Ｓ１１と透過特性Ｓ２１とに基づいて、測定対象３０の心拍及び呼吸を検出する。 Living body information detection apparatus 20, based on the reflection characteristic S 11 calculated above and the transmission characteristic S 21, to detect the heart rate and respiration of the measurement target 30.
　具体的には、まず、生体情報検出装置２０は、上記算出した反射特性Ｓ１１と透過特性Ｓ２１とに基づいて、各アンテナＡＮＴ１、ＡＮＴ２と測定対象３０とを含む測定系の損失ＰＬ（電力散乱率）を算出する。例えば、生体情報検出装置２０は、上記式４を用いて損失ＰＬを算出する。 Specifically, first, the biological information detection apparatus 20, based on the reflection characteristic S 11 calculated above and the transmission characteristic S 21, loss PL (power measurement system comprising a respective antenna ANT1, ANT2 and measured 30 (Scattering rate) is calculated. For example, the biological information detection apparatus 20 calculates the loss PL using the above equation 4.
　生体情報検出装置２０は、上記算出した損失ＰＬ（時系列データ）から心拍の信号及び呼吸の信号を抽出する。具体的には、バンドパスフィルタのようなフィルタリング処理を行うことで心拍の信号及び呼吸の信号を抽出する。 The biological information detection apparatus 20 extracts a heartbeat signal and a respiration signal from the calculated loss PL (time series data). Specifically, a heartbeat signal and a respiration signal are extracted by performing a filtering process such as a bandpass filter.
　また、生体情報検出装置２０は、公知の手段を用いて心拍数及び呼吸数を検出（推定）する。公知の手段としては、高速フーリエ変換（FFT：Fast Fourier Transform）を使用してピーク周波数を選択する方法、心拍の信号のピーク（呼吸の信号のピーク）を数える方法等がある。 Moreover, the biological information detection apparatus 20 detects (estimates) the heart rate and the respiration rate using a known means. Known methods include a method of selecting a peak frequency using a fast Fourier transform (FFT), a method of counting heartbeat signal peaks (respiration signal peaks), and the like.
　［実施形態の効果］
　次に、本実施形態の効果について従来技術と対比して説明する。 [Effect of the embodiment]
Next, the effect of this embodiment will be described in comparison with the prior art.
　上記従来技術においては、反射波又は通過波を単独で用いるため、心拍の信号及び呼吸の信号と体動及び振動に起因するノイズ（正確には、体動や振動によって測定対象３０と各アンテナＡＮＴ１、ＡＮＴ２との相対的な位置関係が変化することに起因するノイズ）とを切り分けることが困難であった。 In the above prior art, since the reflected wave or the passing wave is used alone, the heartbeat signal and the respiration signal and noise caused by body movement and vibration (more precisely, the measurement object 30 and each antenna ANT1 are caused by the body movement and vibration. It is difficult to separate the noise due to the change in the relative positional relationship with ANT2.
　これに対して、本実施形態によれば、損失ＰＬ（時系列データ）を用いるため、比較的小さい体動や振動に起因するノイズを除去することができ、心拍（数）と呼吸（数）を精度よく推定（検出）することができる。 On the other hand, according to the present embodiment, since loss PL (time series data) is used, noise caused by relatively small body movements and vibrations can be removed, and heart rate (number) and respiration (number) Can be estimated (detected) with high accuracy.
　すなわち、本実施形態によれば、反射波（反射特性Ｓ１１）及び通過波（透過特性Ｓ２１）を用いることで、具体的には、反射波（反射特性Ｓ１１）及び通過波（透過特性Ｓ２１）に基づいて算出される損失ＰＬ（時系列データ）を用いることで、損失ＰＬの変化が比較的小さい動き（比較的小さい体動や振動に起因するノイズ）を除去し、損失ＰＬの変化が比較的大きい動き（比較的大きい心拍の信号や呼吸の信号）を抽出するという、一種のノイズキャンセリング効果を期待することができる。その結果、別のフィルタを用いることなく、比較的小さい体動や振動に起因するノイズを除去することができ、心拍や呼吸を精度よく推定することができる。 That is, according to the present embodiment, by using the reflected wave (reflection characteristic S 11 ) and the passing wave (transmission characteristic S 21 ), specifically, the reflected wave (reflection characteristic S 11 ) and the passing wave (transmission characteristic). by using a loss PL is calculated (time series data) based on the S 21), the loss PL changes to remove the relatively small motion (relatively small body movement and noise caused by vibration), losses PL It is possible to expect a kind of noise canceling effect of extracting a relatively large change (a relatively large heartbeat signal or respiration signal). As a result, noise caused by relatively small body movement and vibration can be removed without using another filter, and heartbeat and respiration can be accurately estimated.
　これは、反射波と通過波はどちらか一方が大きくなるともう一方が小さくなるという関係にあり、反射波と通過波のバランスが変わっても、測定系の構成物が変化しなければ損失ＰＬは一定値を取るという性質を利用したことによるものである。 This is because one of the reflected wave and the passing wave becomes larger and the other becomes smaller. Even if the balance between the reflected wave and the passing wave changes, the loss PL is This is because the property of taking a constant value is used.
　［生体情報検出装置（車載装置）のハードウエア構成］
　次に、生体情報検出装置（車載装置）のハードウエア構成について説明する。 [Hardware configuration of biological information detection device (on-vehicle device)]
Next, the hardware configuration of the biological information detection device (vehicle device) will be described.
　図４は、生体情報検出システム１０を車両（図示せず）に適用した例である。 FIG. 4 shows an example in which the biological information detection system 10 is applied to a vehicle (not shown).
　以下、生体情報検出装置２０のことを車載装置２０という。車載装置２０（主に、ＣＰＵ２５）が本発明のコンピュータに相当する。 Hereinafter, the biological information detection device 20 is referred to as the in-vehicle device 20. The in-vehicle device 20 (mainly CPU 25) corresponds to the computer of the present invention.
　図１に示すように、車載装置２０は、高周波信号発生器２１、バンドパスフィルタ２２、カプラ２３、信号受信器２４（以下、デジタル信号処理回路２４ともいう）、ＣＰＵ２５（Central Processing Unit）、メモリ２６等を備えている。 As shown in FIG. 1, the in-vehicle device 20 includes a high-frequency signal generator 21, a bandpass filter 22, a coupler 23, a signal receiver 24 (hereinafter also referred to as a digital signal processing circuit 24), a CPU 25 (Central Processing Unit), a memory. 26 etc.
　第一のアンテナＡＮＴ１は、高周波信号発生器２１が発生し、バンドパスフィルタ２２を通過し、さらに、カプラ２３を経由した高周波信号（送信波）を送信する。図４に示すように、第二のアンテナＡＮＴ２は、ドライバー３０を挟んで第一のアンテナＡＮＴ１の反対側に備えられる。 The first antenna ANT1 is generated by the high-frequency signal generator 21, passes through the band-pass filter 22, and further transmits a high-frequency signal (transmission wave) via the coupler 23. As shown in FIG. 4, the second antenna ANT2 is provided on the opposite side of the first antenna ANT1 with the driver 30 interposed therebetween.
　各アンテナＡＮＴ１、ＡＮＴ２は、運転席に標準的な姿勢（静止した姿勢）で着座したドライバー３０が第一のアンテナＡＮＴ１と第二のアンテナＡＮＴ２とを結ぶ直線上に位置するように配置される。具体的には、各アンテナＡＮＴ１、ＡＮＴ２は、第一のアンテナＡＮＴ１から送信された高周波の一部が運転席に標準的な姿勢で着座したドライバー３０の心臓及び肺を通過し、その通過した高周波（以下、通過波という）が第二のアンテナＡＮＴ２によって受信されるように、ドライバー３０を前後から挟み込んだ形態で配置される。 The antennas ANT1 and ANT2 are arranged so that the driver 30 seated in a standard posture (stationary posture) on the driver's seat is positioned on a straight line connecting the first antenna ANT1 and the second antenna ANT2. Specifically, each of the antennas ANT1 and ANT2 passes a part of the high frequency transmitted from the first antenna ANT1 through the heart and lungs of the driver 30 seated in a standard posture in the driver's seat, and the high frequency that has passed therethrough. It arrange | positions with the form which pinched | interposed the driver 30 from back and front so that it may receive by the 2nd antenna ANT2 (henceforth a passing wave).
　例えば、図４に示すように、第一のアンテナＡＮＴ１を運転席内部に配置し、第二のアンテナＡＮＴ２を運転席正面のダッシュボード内部に配置する。逆に、第二のアンテナＡＮＴ２を運転席内部に配置し、第一のアンテナＡＮＴ１を運転席正面のダッシュボード内部に配置してもよい。 For example, as shown in FIG. 4, the first antenna ANT1 is arranged inside the driver's seat, and the second antenna ANT2 is arranged inside the dashboard in front of the driver's seat. Conversely, the second antenna ANT2 may be arranged inside the driver's seat, and the first antenna ANT1 may be arranged inside the dashboard in front of the driver's seat.
　各アンテナＡＮＴ１、ＡＮＴ２は、配線を介して車載装置２０に接続されている。各アンテナＡＮＴ１、ＡＮＴ２が送受信した信号は、配線を介して車載装置２０に伝達される。 The antennas ANT1 and ANT2 are connected to the in-vehicle device 20 through wiring. Signals transmitted and received by the respective antennas ANT1 and ANT2 are transmitted to the in-vehicle device 20 through wiring.
　高周波信号発生器２１は、一部がドライバー３０で反射されて第一のアンテナＡＮＴ１で受信され、かつ、他の一部がドライバー３０を通過して第二のアンテナＡＮＴ２で受信される周波数成分を含む高周波信号を発生する高周波信号発生器である。 The high-frequency signal generator 21 generates frequency components that are partly reflected by the driver 30 and received by the first antenna ANT1, and the other part passes through the driver 30 and is received by the second antenna ANT2. A high-frequency signal generator that generates a high-frequency signal including.
　高周波信号発生器２１が発生した高周波信号は、特定の周波数成分のみがバンドパスフィルタ２２を通過し、デジタル信号処理回路２４及びアンテナＡＮＴ１に入力される。特定の周波数成分（本発明の電磁波に相当）は、一部がドライバー３０で反射されて第一のアンテナＡＮＴ１で受信され、かつ、他の一部がドライバー３０を通過して第二のアンテナＡＮＴ２で受信される周波数成分で、例えば、数ｋＨｚ～数ＧＨｚの範囲から選定される。主に、高周波信号発生器２１、バンドパスフィルタ２２が、本発明の電磁波出力部に相当する。 Only a specific frequency component of the high-frequency signal generated by the high-frequency signal generator 21 passes through the band-pass filter 22 and is input to the digital signal processing circuit 24 and the antenna ANT1. Part of the specific frequency component (corresponding to the electromagnetic wave of the present invention) is reflected by the driver 30 and received by the first antenna ANT1, and the other part passes through the driver 30 and passes through the second antenna ANT2. For example, the frequency component is selected from the range of several kHz to several GHz. Mainly, the high-frequency signal generator 21 and the band-pass filter 22 correspond to the electromagnetic wave output unit of the present invention.
　カプラ２３は、バンドパスフィルタ２２を通過した高周波信号の進行波と第一のアンテナＡＮＴ１が受信した受信信号を分離して取り出すことができる方向性カプラ（方向性結合器）である。カプラ２３で取り出された受信信号は、デジタル信号処理回路２４に入力される。また、第二のアンテナＡＮＴ２が受信した受信信号も、デジタル信号処理回路２４に入力される。 The coupler 23 is a directional coupler (directional coupler) that can separate and extract the traveling wave of the high-frequency signal that has passed through the bandpass filter 22 and the received signal received by the first antenna ANT1. The reception signal extracted by the coupler 23 is input to the digital signal processing circuit 24. The reception signal received by the second antenna ANT2 is also input to the digital signal processing circuit 24.
　ＣＰＵ２５は、車載装置２０全体の動作を司る。 CPU 25 is responsible for the overall operation of the in-vehicle device 20.
　メモリ２６は、例えば、ＲＡＭ（Random Access Memory）である。 The memory 26 is, for example, a RAM (Random Access Memory).
　[車載装置の機能構成]
　次に、生体情報検出装置（車載装置）の機能構成について説明する。 [Functional configuration of in-vehicle device]
Next, the functional configuration of the biological information detection apparatus (vehicle-mounted apparatus) will be described.
　図５は、生体情報検出装置（車載装置）の機能ブロック図である。 FIG. 5 is a functional block diagram of the biological information detection apparatus (on-vehicle apparatus).
　図５に示すように、デジタル信号処理回路２４は、Ａ／Ｄ変換部２４ａ、反射特性算出部２４ｂ、通過特性算出部２４ｃ、生体情報検出部２４ｄ（損失算出部２４ｄ１、生体情報抽出部２４ｄ２、心拍・呼吸数検出部２４ｄ３）を含む。 As shown in FIG. 5, the digital signal processing circuit 24 includes an A / D conversion unit 24a, a reflection characteristic calculation unit 24b, a transmission characteristic calculation unit 24c, a biological information detection unit 24d (a loss calculation unit 24d1, a biological information extraction unit 24d2, A heart rate / respiration rate detector 24d3).
　Ａ／Ｄ変換部２４ａ（サンプリング部）は、これに入力される３つの信号、すなわち、バンドパスフィルタ２２を通過した高周波信号、第一のアンテナＡＮＴ１で受信されてカプラ２３で分離された受信信号（検波後の信号）、及び、第二のアンテナＡＮＴ２で受信された受信信号（検波後の信号）のＡ／Ｄ変換（サンプリング）を行う。サンプリング周波数は、心拍の信号及び呼吸の信号を抽出できるように考慮された周波数である。 The A / D converter 24a (sampling unit) receives three signals input thereto, that is, a high-frequency signal that has passed through the bandpass filter 22, and a received signal that is received by the first antenna ANT1 and separated by the coupler 23 (A signal after detection) and A / D conversion (sampling) of the received signal (signal after detection) received by the second antenna ANT2. The sampling frequency is a frequency considered so that a heartbeat signal and a respiration signal can be extracted.
　反射特性算出部２４ｂは、第一のアンテナＡＮＴ１が受信した反射波に基づいて、反射特性Ｓ１１を算出する。具体的には、反射特性算出部２４ｂは、上記式１を用いて、サンプリング周期ごとに、反射特性Ｓ１１を算出する。反射特性算出部２４ｂが本発明の第一の特性算出部に相当する。 Reflection characteristic calculating unit 24b, based on the reflected waves first antenna ANT1 is received, calculates the reflection characteristic S 11. Specifically, the reflection characteristic calculating unit 24b, using the above equation 1, for each sampling period, and calculates the reflection characteristic S 11. The reflection characteristic calculation unit 24b corresponds to the first characteristic calculation unit of the present invention.
　通過特性算出部２４ｃは、第二のアンテナＡＮＴ２が受信した通過波に基づいて、通過特性Ｓ２１を算出する。具体的には、通過特性算出部２４ｃは、上記式２を用いて、サンプリング周期ごとに、通過特性Ｓ２１を算出する。通過特性算出部２４ｃが本発明の第二の特性算出部に相当する。 Pass characteristic calculation unit 24c, based on the passage waves second antenna ANT2 is received, calculates the pass characteristics S 21. Specifically, pass characteristic calculation unit 24c, using the above equation 2, for each sampling period, and calculates the pass characteristics S 21. The pass characteristic calculation unit 24c corresponds to the second characteristic calculation unit of the present invention.
　生体情報検出部２４ｄは、損失算出部２４ｄ１と、生体情報抽出部２４ｄ２と、心拍・呼吸数検出部２４ｄ３と、を含む。 The biological information detection unit 24d includes a loss calculation unit 24d1, a biological information extraction unit 24d2, and a heartbeat / respiration rate detection unit 24d3.
　損失算出部２４ｄ１は、反射特性算出部２４ｂが算出した反射特性Ｓ１１と、通過特性算出部２４ｃが算出した通過特性Ｓ２１と、に基づいて、ドライバー３０の心拍の信号（波形）及び呼吸の信号（波形）を含む損失ＰＬを算出する。具体的には、損失算出部２４ｄ１は、上記式４を用いて、サンプリング周期ごとに、損失ＰＬを算出し、メモリ２６に時系列データとして格納する。 Loss calculation unit 24d1 has a reflection characteristic S 11 that the reflection characteristics calculating unit 24b is calculated, the pass characteristic S 21 that pass characteristic calculation unit 24c is calculated, on the basis of the driver 30 heartbeat signal (waveform), and respiratory The loss PL including the signal (waveform) is calculated. Specifically, the loss calculation unit 24d1 calculates the loss PL for each sampling period using the above equation 4, and stores the loss PL in the memory 26 as time series data.
　生体情報抽出部２４ｄ２は、メモリ２６に格納された損失ＰＬ（時系列データ）に対してバンドパスフィルタのようなフィルタリング処理を行うことで、メモリ２６に格納された損失ＰＬ（時系列データ）から心拍の信号及び呼吸の信号を抽出（検出）する。その際、心拍用フィルタ及び呼吸用フィルタが用いられる。 The biological information extraction unit 24d2 performs a filtering process such as a band-pass filter on the loss PL (time series data) stored in the memory 26, so that the loss PL (time series data) stored in the memory 26 is used. A heartbeat signal and a respiration signal are extracted (detected). At that time, a heartbeat filter and a breathing filter are used.
　心拍用フィルタは、上記算出した損失ＰＬ（時系列データ）に含まれる心拍の信号を抽出できるように考慮されたフィルタ（例えば、バンドパスフィルタ）である。同様に、呼吸用フィルタは、上記算出した損失ＰＬ（時系列データ）に含まれる呼吸の信号を抽出できるように考慮されたフィルタ（例えば、バンドパスフィルタ）である。 The heartbeat filter is a filter (for example, a bandpass filter) that is considered so that a heartbeat signal included in the calculated loss PL (time-series data) can be extracted. Similarly, the respiration filter is a filter (for example, a bandpass filter) that is considered so that a respiration signal included in the calculated loss PL (time-series data) can be extracted.
　心拍・呼吸数検出部２４ｄ３は、高速フーリエ変換等の公知の手段を用いて、生体情報抽出部２４ｄ２が抽出した心拍の信号及び呼吸の信号から、心拍数及び呼吸数を検出（推定）する。 The heart rate / respiration rate detection unit 24d3 detects (estimates) the heart rate and the respiration rate from the heart rate signal and the respiration signal extracted by the biological information extraction unit 24d2 using known means such as fast Fourier transform.
　図５に示すように、ＣＰＵ２５は、メモリ２６に読み込まれた所定プログラムを実行することで、比較部２５ａ、ノイズ除去部２５ｂとして機能する。 As shown in FIG. 5, the CPU 25 functions as a comparison unit 25a and a noise removal unit 25b by executing a predetermined program read into the memory 26.
　比較部２５ａは、損失算出部２４ｄ１が算出した損失ＰＬと閾値とを比較する。 The comparison unit 25a compares the loss PL calculated by the loss calculation unit 24d1 with a threshold value.
　ノイズ除去部２５ｂは、バンドパスフィルタのようなフィルタリング処理を行うことで、損失ＰＬ（時系列データ）からノイズ信号を除去する。 The noise removing unit 25b removes a noise signal from the loss PL (time series data) by performing a filtering process such as a band pass filter.
　[生体情報検出システムの動作例１]
　次に、生体情報検出システム１０の動作例１（初期キャリブレーション処理）について説明する。 [Operation example 1 of biological information detection system]
Next, an operation example 1 (initial calibration process) of the biological information detection system 10 will be described.
　図６は、生体情報検出システム１０の初期キャリブレーション処理を説明するためのフローチャートである。 FIG. 6 is a flowchart for explaining an initial calibration process of the biological information detection system 10.
　初期キャリブレーション処理は、ドライバー３０が運転席に標準的な姿勢（静止した姿勢）で着座し、かつ、ドライバー３０の各アンテナＡＮＴ１、ＡＮＴ２に対する相対的な位置関係が変化しない（又はほとんど変化しない）状態で実行される。 In the initial calibration process, the driver 30 sits in the driver's seat in a standard posture (stationary posture), and the relative positional relationship of the driver 30 with respect to the antennas ANT1 and ANT2 does not change (or hardly changes). Executed in state.
　以下の処理は、主に、ＣＰＵ２５が、メモリ２６に読み込まれた所定プログラム（例えば、生体情報検出プログラム）を実行することで実現される。 The following processing is realized mainly by the CPU 25 executing a predetermined program (for example, a biological information detection program) read into the memory 26.
　まず、高周波信号発生器２１が一定期間（例えば、３０秒）高周波信号を発生する（ステップＳ１０）。高周波信号発生器２１が発生した高周波信号は、任意の周波数成分のみがバンドパスフィルタ２２を通過し、デジタル信号処理回路２４及び第一のアンテナＡＮＴ１に入力される。第一のアンテナＡＮＴ１は、これに入力される高周波信号（電波）を送信する。 First, the high frequency signal generator 21 generates a high frequency signal for a certain period (for example, 30 seconds) (step S10). Only an arbitrary frequency component of the high frequency signal generated by the high frequency signal generator 21 passes through the band pass filter 22 and is input to the digital signal processing circuit 24 and the first antenna ANT1. The first antenna ANT1 transmits a high frequency signal (radio wave) input thereto.
　次に、第一のアンテナＡＮＴ１がドライバー３０で反射された反射波を受信し、第二のアンテナＡＮＴ２がドライバー３０を通過した通過波を受信する（ステップＳ１１）。第一のアンテナＡＮＴ１が受信した受信信号は、カプラ２３で取り出されてデジタル信号処理回路２４に入力される。第二のアンテナＡＮＴ２で受信された受信信号も、デジタル信号処理回路２４に入力される。 Next, the first antenna ANT1 receives the reflected wave reflected by the driver 30, and the second antenna ANT2 receives the passing wave that has passed through the driver 30 (step S11). The received signal received by the first antenna ANT1 is extracted by the coupler 23 and input to the digital signal processing circuit 24. The reception signal received by the second antenna ANT2 is also input to the digital signal processing circuit 24.
　次に、検波部（図示せず）がステップＳ１１で受信した反射波（受信信号）及び通過波（受信信号）の検波を行う（ステップＳ１２）。検波部は、例えば、所定回路で、又は、ＣＰＵ２５が所定プログラムを実行することで実現される。 Next, the detection unit (not shown) detects the reflected wave (reception signal) and the passing wave (reception signal) received in step S11 (step S12). The detection unit is realized by, for example, a predetermined circuit or by the CPU 25 executing a predetermined program.
　次に、Ａ／Ｄ変換部２４ａが、バンドパスフィルタ２２を通過した高周波信号、第一のアンテナＡＮＴ１が受信してカプラ２３で分離された受信信号（ステップＳ１２の検波後の信号）、及び、第二のアンテナＡＮＴ２が受信した受信信号（ステップＳ１２の検波後の信号）のサンプリングを行う。 Next, the A / D conversion unit 24a receives the high-frequency signal that has passed through the band-pass filter 22, the reception signal received by the first antenna ANT1 and separated by the coupler 23 (the signal after detection in step S12), and The received signal (the signal after the detection in step S12) received by the second antenna ANT2 is sampled.
　次に、反射特性算出部２４ｂが上記式１を用いて、サンプリング周期ごとに、反射特性Ｓ１１を算出し、かつ、通過特性算出部２４ｃが上記式２を用いて、サンプリング周期ごとに、通過特性Ｓ２１を算出する（ステップＳ１４）。 Then, the reflection characteristic calculation unit 24b by using the above equation 1, for each sampling period, and calculates the reflection characteristic S 11, and, passing characteristic calculation unit 24c by using the above equation 2, for each sampling period, passing calculating a characteristic S 21 (step S14).
　次に、損失算出部２４ｄ１が、上記式４を用いて、サンプリング周期ごとに、損失ＰＬを算出する（ステップＳ１５）。算出した損失ＰＬは、メモリ２６に初期値（閾値）として格納される（ステップＳ１６）。算出した損失ＰＬは、平均値データ（又は時系列データ）として格納される。なお、算出した損失ＰＬは、例えばこれを±50%したものを初期値としてメモリ２６に格納してもよい。 Next, the loss calculation unit 24d1 calculates the loss PL for each sampling period using the above equation 4 (step S15). The calculated loss PL is stored as an initial value (threshold value) in the memory 26 (step S16). The calculated loss PL is stored as average value data (or time series data). Note that the calculated loss PL may be stored in the memory 26 as an initial value obtained by, for example, ± 50% of the loss PL.
　以上により、初期キャリブレーション処理が終了する。上記ステップＳ１０～Ｓ１６が本発明の閾値生成部に相当する。 This completes the initial calibration process. The above steps S10 to S16 correspond to the threshold value generation unit of the present invention.
　[生体情報検出システムの動作例２]
　次に、生体情報検出システム１０の動作例２（生体情報検出処理）について説明する。 [Operation example 2 of biological information detection system]
Next, an operation example 2 (biological information detection process) of the biological information detection system 10 will be described.
　図７は、生体情報検出システム１０の生体情報検出処理を説明するためのフローチャートである。 FIG. 7 is a flowchart for explaining the biological information detection process of the biological information detection system 10.
　生体情報検出処理は、例えば、運転席に標準的な姿勢で着座したドライバー３０が運転している状態で実行される。 The biological information detection process is executed, for example, in a state where the driver 30 sitting in a standard posture on the driver's seat is driving.
　以下の処理は、主に、ＣＰＵ２５が、メモリ２６に読み込まれた所定プログラム（例えば、生体情報検出プログラム）を実行することで実現される。 The following processing is realized mainly by the CPU 25 executing a predetermined program (for example, a biological information detection program) read into the memory 26.
　まず、高周波信号発生器２１が高周波信号を発生する（ステップＳ１０Ａ）。高周波信号発生器２１が発生した高周波信号は、任意の周波数成分のみがバンドパスフィルタ２２を通過し、デジタル信号処理回路２４及び第一のアンテナＡＮＴ１に入力される。第一のアンテナＡＮＴ１は、これに入力される高周波信号（電波）を送信する。 First, the high frequency signal generator 21 generates a high frequency signal (step S10A). Only an arbitrary frequency component of the high frequency signal generated by the high frequency signal generator 21 passes through the band pass filter 22 and is input to the digital signal processing circuit 24 and the first antenna ANT1. The first antenna ANT1 transmits a high frequency signal (radio wave) input thereto.
　次に、第一のアンテナＡＮＴ１がドライバー３０で反射された反射波を受信し、第二のアンテナＡＮＴ２がドライバー３０を通過した通過波を受信する（ステップＳ１１Ａ）。第一のアンテナＡＮＴ１が受信した受信信号は、カプラ２３で取り出されてデジタル信号処理回路２４に入力される。第二のアンテナＡＮＴ２で受信された受信信号も、デジタル信号処理回路２４に入力される。 Next, the first antenna ANT1 receives the reflected wave reflected by the driver 30, and the second antenna ANT2 receives the passing wave that has passed through the driver 30 (step S11A). The received signal received by the first antenna ANT1 is extracted by the coupler 23 and input to the digital signal processing circuit 24. The reception signal received by the second antenna ANT2 is also input to the digital signal processing circuit 24.
　次に、検波部（図示せず）がステップＳ１１Ａで受信した反射波（受信信号）及び通過波（受信信号）の検波を行う（ステップＳ１２Ａ）。検波部は、例えば、所定回路で、又は、ＣＰＵ２５が所定プログラムを実行することで実現される。 Next, the detection unit (not shown) detects the reflected wave (reception signal) and the passing wave (reception signal) received in step S11A (step S12A). The detection unit is realized by, for example, a predetermined circuit or by the CPU 25 executing a predetermined program.
　次に、Ａ／Ｄ変換部２４ａが、バンドパスフィルタ２２を通過した高周波信号、第一のアンテナＡＮＴ１が受信してカプラ２３で分離された受信信号（ステップＳ１２の検波後の信号）、及び、第二のアンテナＡＮＴ２が受信した受信信号（ステップＳ１２の検波後の信号）のサンプリングを行う。 Next, the A / D conversion unit 24a receives the high-frequency signal that has passed through the band-pass filter 22, the reception signal received by the first antenna ANT1 and separated by the coupler 23 (the signal after detection in step S12), and The received signal (the signal after the detection in step S12) received by the second antenna ANT2 is sampled.
　次に、反射特性算出部２４ｂが上記式１を用いて、サンプリング周期ごとに、反射特性Ｓ１１を算出し、かつ、通過特性算出部２４ｃが上記式２を用いて、サンプリング周期ごとに、通過特性Ｓ２１を算出する（ステップＳ１４Ａ）。 Then, the reflection characteristic calculation unit 24b by using the above equation 1, for each sampling period, and calculates the reflection characteristic S 11, and, passing characteristic calculation unit 24c by using the above equation 2, for each sampling period, passing calculating a characteristic S 21 (step S14A).
　次に、損失算出部２４ｄ１が、上記式４を用いて、サンプリング周期ごとに、損失ＰＬを算出する（ステップＳ１５Ａ）。 Next, the loss calculation unit 24d1 calculates the loss PL for each sampling period using the above equation 4 (step S15A).
　次に、比較部２５ａが、サンプリング周期ごとに、損失算出部２４ｄ１が算出した損失ＰＬとステップＳ１６でメモリ２６に格納された初期値（閾値）と比較する（ステップＳ２０）。 Next, the comparison unit 25a compares the loss PL calculated by the loss calculation unit 24d1 with the initial value (threshold value) stored in the memory 26 in step S16 for each sampling period (step S20).
　その結果、損失ＰＬが初期値より大きい場合（損失＞初期値）、ノイズ除去部２５ｂが、フィルタリング処理を行うことで、損失ＰＬからノイズ信号を除去する（ステップＳ２１）。この場合、ノイズ信号を除去した損失ＰＬがメモリ２６に格納される（ステップＳ２２）。 As a result, when the loss PL is larger than the initial value (loss> initial value), the noise removing unit 25b performs a filtering process to remove the noise signal from the loss PL (step S21). In this case, the loss PL from which the noise signal has been removed is stored in the memory 26 (step S22).
　一方、ステップＳ２０の比較の結果、損失ＰＬが初期値より小さい場合（損失＜初期値）、フィルタリング処理は行われず、ステップＳ１５Ａで算出された損失ＰＬがメモリ２６に格納される（ステップＳ２２）。 On the other hand, if the loss PL is smaller than the initial value (loss <initial value) as a result of the comparison in step S20, the filtering process is not performed, and the loss PL calculated in step S15A is stored in the memory 26 (step S22).
　上記ステップ１４Ａ～Ｓ２３の処理は、サンプリング周期が終了するまで繰り返し実行される（ステップＳ２３：Ｎｏ）。これにより、メモリ２６にノイズ信号を除去した損失ＰＬ（時系列データ）が格納される。 The processes in steps 14A to S23 are repeatedly executed until the sampling period is completed (step S23: No). Thereby, the loss PL (time-series data) from which the noise signal is removed is stored in the memory 26.
　一方、サンプリング周期が終了した場合（ステップＳ２３：Ｙｅｓ）、生体情報抽出部２４ｄ２が、フィルタリング処理を行うことで、メモリ２６に格納された損失ＰＬ（時系列データ）から心拍の信号（波形）及び呼吸（波形）の信号を抽出（検出）する（ステップＳ２４）。 On the other hand, when the sampling cycle is ended (step S23: Yes), the biological information extraction unit 24d2 performs a filtering process, so that a heartbeat signal (waveform) and a loss PL (time-series data) stored in the memory 26 are obtained. A breathing (waveform) signal is extracted (detected) (step S24).
　次に、心拍・呼吸数検出部２４ｄ３が、生体情報抽出部２４ｄ２が抽出した心拍の信号及び呼吸の信号から、心拍数及び呼吸数を検出（推定）する。 Next, the heart rate / respiration rate detection unit 24d3 detects (estimates) the heart rate and respiration rate from the heart rate signal and respiration signal extracted by the biological information extraction unit 24d2.
　以上により、生体情報検出処理が終了する。 Thus, the biological information detection process is completed.
　以上説明したように、本実施形態によれば、ドライバー３０の動きの影響を受けづらい生体情報（例えば、心拍及び呼吸）の検出を実現することができる生体情報検出装置２０、生体情報検出プログラムを提供することができる。ここでいうドライバー３０の動きとは、第一のアンテナＡＮＴ１と第二のアンテナＡＮＴ２とを結ぶ直線方向（前後方向）の動き、その直線に対して垂直の方向（例えば、左右方向）の動きのいずれか、又は、両方のことである。 As described above, according to the present embodiment, the biological information detection apparatus 20 and the biological information detection program that can realize detection of biological information (for example, heartbeat and respiration) that is not easily influenced by the movement of the driver 30. Can be provided. The movement of the driver 30 here refers to a movement in a linear direction (front-rear direction) connecting the first antenna ANT1 and the second antenna ANT2, and a movement in a direction perpendicular to the straight line (for example, left-right direction). Either or both.
　次に、変形例について説明する。 Next, a modified example will be described.
　上記実施形態においては、測定対象３０が自動車のドライバーであり、生体情報検出装置２０が車両に搭載される車載装置２０である例について説明したが、これに限らない。例えば、測定対象３０はベッドで寝ている人やそれ以外の人であってもよく、生体情報検出装置２０はベッド、その周辺、又はそれ以外の場所に設けてもよい。 In the above embodiment, the example in which the measurement target 30 is a driver of an automobile and the biological information detection device 20 is the in-vehicle device 20 mounted on the vehicle has been described, but the present invention is not limited thereto. For example, the measurement target 30 may be a person sleeping in a bed or other people, and the biological information detection device 20 may be provided in the bed, in the vicinity thereof, or elsewhere.
　また、上記実施形態では、心拍の信号（波形）及び呼吸（波形）の信号を抽出し（ステップＳ２４）、かつ、心拍数及び呼吸数を検出（推定）する例について説明したが、これに限らない。例えば、心拍の信号（波形）及び呼吸（波形）の信号のうち少なくとも一方を抽出してもよい。また、心拍数及び呼吸数のうち少なくとも一方を検出（推定）してもよい。 Moreover, although the said embodiment demonstrated the example which extracts the signal (waveform) of a heartbeat and the signal of a respiration (waveform) (step S24), and detects (estimates) a heart rate and a respiration rate, it does not restrict to this. Absent. For example, at least one of a heartbeat signal (waveform) and a respiration (waveform) signal may be extracted. Further, at least one of the heart rate and the respiratory rate may be detected (estimated).
１０…生体情報検出システム、２０…生体情報検出装置（車載装置）、２１…高周波信号発生器、２２…バンドパスフィルタ、２３…カプラ、２４…信号受信器（デジタル信号処理回路）、２４ａ…Ａ／Ｄ変換部、２４ｂ…反射特性算出部、２４ｃ…通過特性算出部、２４ｄ…生体情報検出部、２４ｄ１…損失算出部、２４ｄ２…生体情報抽出部、２４ｄ３…心拍・呼吸数検出部、２５…ＣＰＵ、２５ａ…比較部、２５ｂ…ノイズ除去部、２６…メモリ、３０…測定対象（ドライバー）、ＡＮＴ１…第一のアンテナ、ＡＮＴ２…第二のアンテナ、ＰＬ…損失、Ｓ１１…反射特性、Ｓ２１…通過特性 DESCRIPTION OF SYMBOLS 10 ... Biological information detection system, 20 ... Biological information detection apparatus (vehicle equipment), 21 ... High frequency signal generator, 22 ... Band pass filter, 23 ... Coupler, 24 ... Signal receiver (digital signal processing circuit), 24a ... A / D conversion unit, 24b ... reflection characteristic calculation unit, 24c ... passage characteristic calculation unit, 24d ... biological information detection unit, 24d1 ... loss calculation unit, 24d2 ... biological information extraction unit, 24d3 ... heart rate / respiration rate detection unit, 25 ... CPU, 25a ... comparing unit, 25b ... noise removing unit, 26 ... memory, 30 ... measurement object (driver), ANT1 ... first antenna, ANT2 ... second antenna, PL ... loss, S 11 ... reflection characteristics, S 21 ... Passing characteristics

Claims (8)

  1. 　第一のアンテナと、生体を挟んで前記第一のアンテナの反対側に備えられた第二のアンテナと、を有する生体情報検出システムにおける生体情報検出装置であって、
    　前記第一のアンテナに電磁波を出力させる電磁波出力部と、
    　前記第一のアンテナで受信された前記電磁波の反射波の第一の特性と前記第二のアンテナで受信された前記電磁波の第二の特性とに基づいて、前記生体の心拍及び呼吸のうち少なくとも一方を検出する生体情報検出部と、を備える生体情報検出装置。     A biological information detection apparatus in a biological information detection system having a first antenna and a second antenna provided on the opposite side of the first antenna across a living body,
    An electromagnetic wave output unit for outputting an electromagnetic wave to the first antenna;
    Based on the first characteristic of the reflected wave of the electromagnetic wave received by the first antenna and the second characteristic of the electromagnetic wave received by the second antenna, at least of the heartbeat and respiration of the living body A biological information detection apparatus comprising: a biological information detection unit that detects one of them.
  2. 　前記生体情報検出部は、
    　前記第一の特性と前記第二の特性とに基づいて、前記生体の心拍の信号及び呼吸の信号を含む損失を算出する損失算出部と、
    　前記損失から前記生体の心拍の信号及び呼吸の信号のうち少なくとも一方を抽出する生体情報抽出部と、をさらに備える請求項１に記載の生体情報検出装置。     The biological information detection unit
    A loss calculating unit that calculates a loss including a heartbeat signal and a respiration signal of the living body based on the first characteristic and the second characteristic;
    The biological information detection apparatus according to claim 1, further comprising: a biological information extraction unit that extracts at least one of a heartbeat signal and a respiration signal of the living body from the loss.
  3. 　前記第一のアンテナが受信した前記電磁波に基づいて、前記第一の特性を算出する第一の特性算出部と、
    　前記第二のアンテナが受信した前記電磁波に基づいて、前記第二の特性を算出する第二の特性算出部と、をさらに備え、
    　前記損失算出部は、前記第一の特性算出部が算出した前記第一の特性と前記第二の特性算出部が算出した前記第二の特性とに基づいて、前記生体の心拍の信号及び呼吸の信号を含む損失を算出する請求項２に記載の生体情報検出装置。     A first characteristic calculator that calculates the first characteristic based on the electromagnetic wave received by the first antenna;
    A second characteristic calculator that calculates the second characteristic based on the electromagnetic wave received by the second antenna; and
    The loss calculation unit is configured to calculate a heartbeat signal and a respiration of the living body based on the first characteristic calculated by the first characteristic calculation unit and the second characteristic calculated by the second characteristic calculation unit. The biological information detection apparatus according to claim 2, wherein a loss including the signal is calculated.
  4. 　前記損失算出部が算出した損失が閾値より大きい場合、フィルタリング処理を行うノイズ除去部をさらに備える請求項２又は３に記載の生体情報検出装置。 The biological information detection apparatus according to claim 2 or 3, further comprising a noise removal unit that performs a filtering process when the loss calculated by the loss calculation unit is greater than a threshold value.
  5. 　前記閾値を生成する閾値生成部をさらに備える請求項４に記載の生体情報検出装置。 The biological information detection apparatus according to claim 4, further comprising a threshold value generation unit that generates the threshold value.
  6. 　前記第一の特性は、前記生体で反射されて前記第一のアンテナで受信された前記電磁波の反射波の反射特性であり、
    　前記第二の特性は、前記生体を通過して前記第二のアンテナで受信された前記電磁波の通過特性である請求項１から５のいずれか１項に記載の生体情報検出装置。     The first characteristic is a reflection characteristic of a reflected wave of the electromagnetic wave reflected by the living body and received by the first antenna,
    6. The biological information detection apparatus according to claim 1, wherein the second characteristic is a transmission characteristic of the electromagnetic wave received by the second antenna through the living body.
  7. 　前記電磁波は、高周波である請求項１から６のいずれか１項に記載の生体情報検出装置。 The biological information detection apparatus according to claim 1, wherein the electromagnetic wave is a high frequency.
  8. 　第一のアンテナに電磁波を出力させ、
    　前記第一のアンテナで受信された前記電磁波の反射波の第一の特性と第二のアンテナで受信された前記電磁波の第二の特性とに基づいて、生体の心拍及び呼吸のうち少なくとも一方を検出する、
    処理をコンピュータに実行させる生体情報検出プログラム。     Let the first antenna output electromagnetic waves,
    Based on the first characteristic of the reflected wave of the electromagnetic wave received by the first antenna and the second characteristic of the electromagnetic wave received by the second antenna, at least one of heartbeat and respiration of the living body is determined. To detect,
    A biological information detection program for causing a computer to execute processing.
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2020062291A (en) * 2018-10-18 2020-04-23 Ｓｉｍｐｌｅｘ Ｑｕａｎｔｕｍ株式会社 Biological information detection device and biological information detection method
CN111685727A (en) * 2019-03-12 2020-09-22 佳能医疗***株式会社 Biological information monitoring device and magnetic resonance imaging device

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0461849A (en) * 1990-06-29 1992-02-27 Colleen Denshi Kk Peripheral circulation detecting device
JP2013153783A (en) * 2012-01-26 2013-08-15 Toyota Infotechnology Center Co Ltd Heartbeat detector and heartbeat detection method
US20140058256A1 (en) * 2011-04-29 2014-02-27 Nederlandse Organisatie Voor Toegepast- Natuurwetenschappelijk Onderzoek Tno Radar apparatus for detecting multiple life - signs of a subject, a method and a computer program product

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0461849A (en) * 1990-06-29 1992-02-27 Colleen Denshi Kk Peripheral circulation detecting device
US20140058256A1 (en) * 2011-04-29 2014-02-27 Nederlandse Organisatie Voor Toegepast- Natuurwetenschappelijk Onderzoek Tno Radar apparatus for detecting multiple life - signs of a subject, a method and a computer program product
JP2013153783A (en) * 2012-01-26 2013-08-15 Toyota Infotechnology Center Co Ltd Heartbeat detector and heartbeat detection method

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2020062291A (en) * 2018-10-18 2020-04-23 Ｓｉｍｐｌｅｘ Ｑｕａｎｔｕｍ株式会社 Biological information detection device and biological information detection method
CN111685727A (en) * 2019-03-12 2020-09-22 佳能医疗***株式会社 Biological information monitoring device and magnetic resonance imaging device
CN111685727B (en) * 2019-03-12 2024-05-14 佳能医疗***株式会社 Biological information monitoring device and magnetic resonance imaging device

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