JP6909088B2 - Measuring equipment, measuring methods, and measuring programs - Google Patents

Description

This disclosure relates to a technique for acquiring biometric information, and more specifically, to a technique for non-contactly acquiring biometric information.

A technique for measuring the heart rate of a living body in a non-contact manner is known. Heart rate refers to the number of times the heart beats within a certain period of time (for example, 1 minute). By measuring the heart rate in a non-contact manner, the burden on the living body is reduced.

Regarding the non-contact heart rate measurement technique, Japanese Patent Application Laid-Open No. 2010-120493 (Patent Document 1) discloses a biological signal detection device for non-contactly detecting a driver's heart rate and respiratory rate. .. The biological signal detection device measures the driver's heart rate, respiration, etc. using a Doppler sensor.

More specifically, the Doppler sensor irradiates the driver with microwaves and receives the reflected waves of the microwaves. The frequency of the reflected wave increases as the living body approaches the Doppler sensor, and the frequency of the reflected wave decreases as the living body moves away from the Doppler sensor. That is, when the distance between the living body and the Doppler sensor fluctuates, a frequency difference or a phase difference (so-called Doppler shift) occurs between the irradiated microwave and its reflected wave. The Doppler sensor outputs a signal (hereinafter, also referred to as “Doppler signal”) that correlates with the phase difference. The biological signal detection device disclosed in Patent Document 1 measures the driver's heart rate, respiration, and the like based on the detected frequency component of the Doppler signal.

Japanese Unexamined Patent Publication No. 2010-20493

Various movements such as heart rate and respiration occur in the living body. Therefore, the Doppler signal detected by the Doppler sensor includes a signal component caused by the heartbeat of the living body (hereinafter, also referred to as “heartbeat signal”) and a signal component caused by the respiration of the living body (hereinafter, also referred to as “respiratory signal”). Say.) Is included.

As described above, the Doppler sensor detects fluctuations in the distance between the living body and the sensor. Therefore, when the living body is moving, the ratio of the heartbeat signal and the respiration signal in the Doppler signal becomes small. Therefore, the conventional measuring device as disclosed in Patent Document 1 may detect inaccurate biological information (for example, heart rate, respiratory rate) when the living body is moving. Therefore, there is a need for a measuring device capable of suppressing the detection of inaccurate biological information.

The present disclosure has been made to solve the above-mentioned problems, and an object in a certain aspect is to provide a measuring device capable of suppressing the detection of inaccurate biological information more than before. The purpose in other aspects is to provide a measurement method that can suppress the detection of inaccurate biometric information more than before. The purpose in yet another aspect is to provide a measurement program that can suppress the detection of inaccurate biometric information more than before.

According to certain embodiments, a measuring device for measuring biological information is provided. This measuring device irradiates a living body with microwaves, receives the reflected wave of the microwave, and outputs a Doppler signal based on the microwave and the reflected wave, and a living body based on the Doppler signal. It is provided with a control circuit for detecting biometric information including at least one of the heart rate and the respiration rate of the above, and a memory for storing the detected biometric information. The control circuit is a comparison unit that compares the detected biological information with the past biological information stored in the memory, and the biological information detected when the comparison result satisfies a predetermined condition, or the biological body. It includes an output unit that outputs biometric information derived based on information and past biometric information.

A measuring device according to an embodiment can suppress the detection of inaccurate biometric information more than before.
The above and other objectives, features, aspects and advantages of the disclosed technical features will become apparent from the following detailed description of the invention, which is understood in connection with the accompanying drawings.

It is a figure which shows the schematic structure of the measuring apparatus according to an embodiment. It is a figure for demonstrating the influence which a respiratory signal has on a heartbeat signal. It is a figure which shows the whole structure of the measurement system according to Embodiment 1. FIG. It is a block diagram for demonstrating the structure of the control circuit according to Embodiment 1. FIG. It is a block diagram which shows an example of the structure of the analog signal processing circuit according to Embodiment 1. It is a flowchart which shows the heart rate measurement process. It is a flowchart which shows the measurement process of a respiratory rate. It is a flowchart which shows the body motion detection process. It is a block diagram for demonstrating the structure of the control circuit included in the measuring apparatus according to Embodiment 2. It is a flowchart which shows the heart rate measurement processing according to Embodiment 2. It is a flowchart which shows the measurement process of the respiratory rate according to Embodiment 2. It is a figure for demonstrating the detection accuracy of the heart rate in a state where a living body is not moving. It is a figure for demonstrating the detection accuracy of the heart rate in a state where a living body is moving. It is a block diagram for demonstrating the structure of the control circuit included in the measuring apparatus according to Embodiment 3. It is a figure which shows an example of the data structure of the accuracy table 1500. It is a figure which shows an example of the data structure of the accuracy table 1600. 6 is a flowchart showing a heart rate measurement process according to the third embodiment. It is a flowchart which shows the measurement process of the respiratory rate according to Embodiment 3. It is a flowchart which shows the body movement detection process according to Embodiment 3.

Hereinafter, embodiments of this technical idea will be described in detail with reference to the drawings. In the following description, the same parts and components are designated by the same reference numerals. Their names and functions are the same. Therefore, the detailed description of them will not be repeated. In addition, each embodiment and each modification described below may be selectively combined as appropriate.

[Technical Thought]
First, the technical concept of the measuring device 100 according to the embodiment will be described. FIG. 1 is a diagram showing a schematic configuration of a measuring device 100 according to an embodiment.

With reference to FIG. 1, the measuring device 100 includes a Doppler sensor 40, a control circuit 152, and a memory 154.

The Doppler sensor 40 irradiates the living body P to be measured with microwaves, and receives the reflected waves of the microwaves from the living body P. The living body P is, for example, an animal such as a human being. When the living body P approaches the Doppler sensor 40, the frequency of the reflected wave becomes high, and when the living body P moves away from the Doppler sensor, the frequency of the reflected wave becomes low. That is, the phase of the Doppler signal changes depending on the respiration and heartbeat of the living body P. Therefore, a phase difference (so-called Doppler shift) occurs between the irradiated microwave and its reflected wave. The Doppler sensor 40 outputs a Doppler signal that correlates with the phase difference to the control circuit 152.

The control circuit 152 includes a detection unit 85, a comparison unit 86, and an output unit 52. The detection unit 85 detects the biological information of the living body P based on the Doppler signal input from the Doppler sensor 40. As an example, the detection unit 85 detects the heart rate and the respiratory rate of the living body P. These specific detection methods will be described later. The detection unit 85 outputs the detected biological information to the comparison unit 86.

(Reason for detecting inaccurate biometric information-Part 1)
By the way, when the Doppler sensor 40 is fixed, the Doppler signal detects the fluctuation of the distance between the living body P and the Doppler sensor 40, that is, the body movement of the living body P. Hereinafter, "body movement" is defined as a concept including both minute movements of the living body P caused by respiration and heartbeat and large movements caused by "body movement". On the other hand, "body movement" represents a large movement such as shaking of the body, and is defined as a concept that does not include the above-mentioned minute movement.

When the body of the living body P is moving, the Doppler signal includes the waveform of the movement of the body and the harmonics of the waveform. In addition, the amplitudes of the waveforms and harmonics of such body movements are larger than the amplitudes of the heartbeat signal and the respiratory signal. Therefore, the detection unit 85 may erroneously detect the periodicity of the waveform caused by the movement of the body as the heart rate or the respiratory rate.

(Reason for detecting inaccurate biometric information-Part 2)
FIG. 2 is a diagram for explaining the influence of the respiratory signal on the heartbeat signal. The graph shown in FIG. 2 shows the spectrum of the Doppler signal, that is, the signal strength of the Doppler signal for each frequency band.

More specifically, the horizontal axis of the graph represents frequency (unit: "Hz"). Multiplying the frequency by "60" gives the frequency of the living body around 1 minute. The frequency represents the heart rate and the respiratory rate of the living body. Since the unit of heart rate and respiratory rate is represented by "bpm (Beats Per Minute)", the horizontal axis of the graph may be represented by "bpm". The vertical axis of the graph shows the signal strength.

As shown in the graph, the Doppler signal includes heartbeat components A1 to A3 caused by the heartbeat of the living body and respiratory components B1 to B3 and B5 caused by the respiration of the living body. Since the waveform of the respiratory signal is close to a triangular wave, the frequency component of the respiratory signal corresponds not only to the frequency component corresponding to the respiratory rate but also to an integral multiple (typically, an odd multiple of 3 times or more) of the respiratory rate. Frequency components (hereinafter, also referred to as “higher frequency components”) B2, B3, and B5 are included. In particular, the signal intensity of the respiratory component B3, which corresponds to three times the respiratory rate, becomes stronger.

Generally, a person's respiratory rate is about 16 to 19 bpm. Therefore, the band of the respiratory component B3 is 48 to 57 bpm. On the other hand, a person's heart rate is about 65 to 75 bpm. As described above, the band of the respiratory component B3 is close to the band of the heartbeat component A1. In addition, since the amplitude of the respiratory signal is about 10 times or more the amplitude of the heartbeat signal, the respiratory component B3 becomes a large noise in detecting the heart rate. Therefore, the detection unit 85 may erroneously detect the periodicity of the respiratory component B3 as the heart rate.

In this way, the detection unit 85 can erroneously detect the biological information of the living body P. The measuring device 100 according to the embodiment excludes erroneously detected biological information by the action of the comparison unit 86.

(Structure that excludes inaccurate biometric information)
With reference to FIG. 1 again, the comparison unit 86 includes biometric information input from the detection unit 85 (hereinafter, also referred to as “neonatal information”) and biometric information stored in the history area 155 of the memory 154, that is, Compare with the biometric information detected in the past (hereinafter, also referred to as "old biometric information"). The comparison unit 86 outputs new body information to the output unit 52 when the comparison result satisfies a predetermined condition. That is, the comparison unit 86 does not output the neonatal information to the output unit 52 when the condition is not satisfied.

The old biometric information may be, for example, the newest biometric information among the biometric information stored in the history area 155. The predetermined condition includes, for example, that the volatility of the neonatal information with respect to the old biometric information is within a predetermined value (for example, ± 10%).

Basically, at rest, biometric information, including heart rate and respiratory rate, does not fluctuate rapidly in a short period of time. Therefore, when the volatility of the neonatal information with respect to the old biometric information becomes larger than a predetermined value, there is a high possibility that inaccurate biometric information will be detected due to the "body movement" of the biological P, or respiration. Inaccurate heart rate is likely to be detected due to the periodicity of component B3. Using this characteristic, the comparison unit 86 according to the embodiment determines that the neonatal information is correct biometric information only when the comparison result between the old biometric information and the neoplastic body information satisfies a predetermined condition. Then, the new body information is output to the output unit 52.

In a certain aspect, the comparison unit 86 may be configured to output the old biometric information to the output unit 52 in place of the neonatal information when the neonatal information does not satisfy the above conditions.

The output unit 52 outputs the information input from the comparison unit 86 to a device such as a display or a speaker. Thereby, the observer of the living body P or the living body P can recognize the biological information of the living body P.

In another aspect, the output unit 52 may be configured to output the information input from the comparison unit 86 to an external device such as a smartphone. Thereby, the observer of the living body P or the living body P can more easily recognize the biological information of the living body P.

According to the above, the measuring device 100 according to the embodiment can determine whether the detected biological information is correct biological information or noise by comparing the detected biological information with the past biological information. Therefore, the measuring device 100 according to the embodiment can suppress the detection of inaccurate biological information as compared with the conventional measuring device. The detailed configuration and control of the measuring device 100 according to the embodiment will be described below.

[Embodiment 1]
FIG. 3 is a diagram showing an overall configuration of the measurement system 1000 according to the first embodiment. With reference to FIG. 3, the measurement system 1000 includes a measurement device 100 for monitoring the living body P and a terminal device 200. The terminal device 200 is a terminal for receiving the measurement result by the measuring device 100, and is, for example, a smartphone. However, the terminal device 200 may be another device such as a foldable mobile phone, a tablet terminal device, or a personal computer.

The network 300 for connecting the measuring device 100 and the terminal device 200 to each other includes various networks such as the Internet. The network 300 is not limited to this, and a wired communication method may be adopted, or another wireless communication method such as a wireless LAN (local area network) may be adopted.

(Measuring device 100)
The measuring device 100 detects biological information in a non-contact manner. Such a measuring device 100 is used in various situations. As an example, the measuring device 100 is used to measure the biological information of the driver when driving a car. Alternatively, the measuring device 100 is used to measure the biological information of the patient in the nursing facility or the medical facility.

The measuring device 100 includes a Doppler sensor 40, a control circuit 152, a memory 154, a speaker 156, and a communication interface 158 as main components. The measuring device 100 may include a display for displaying various information and an input device such as a button for receiving various inputs from the user.

The control circuit 152 typically includes a microprocessor including a CPU and the like, an analog signal processing circuit for processing an analog signal from the Doppler sensor 40, and an AD (Analog to Digital) converter. The detailed configuration of the control circuit 152 will be described later. The microprocessor reads and executes the program stored in the memory 154, and functions as a control unit that controls the operation of each unit of the measuring device 100. For example, the microprocessor realizes the processing of the control circuit 152, which will be described later, by executing the program.

The memory 154 is realized by a RAM (Random Access Memory), a ROM (Read-Only Memory), or the like. The memory 154 stores a program executed by the microprocessor, data used by the microprocessor, and the like. The memory 154 includes a history area 155 for storing old biometric information. In one aspect, the history area 155 is configured by a non-volatile memory. In another aspect, the history area 155 is composed of volatile memory and functions as a ring buffer.

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

The Doppler sensor 40 irradiates the living body P with microwaves, and outputs a signal reflecting the movement of the body of the living body P to the control circuit 152 from the reflected microwaves. Further, the Doppler sensor 40 generates an I-channel signal and a Q-channel signal that are orthogonal to each other from the input reflected signal.

Specifically, the Doppler sensor 40 includes an oscillation circuit 21, amplifiers 22A and 22B, a transmitting antenna 25, a receiving antenna 30, mixers 32I and 32Q, LPF33I and 33Q, and a 90-degree phase shifter 38. include. The transmitting antenna 25 and the receiving antenna 30 are composed of a flat antenna. The transmitting antenna 25 and the receiving antenna 30 may be composed of a waveguide antenna or a dielectric antenna.

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

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

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

The signal frequency-converted (down-converted) by the mixer 32I is input to the LPF33I. The LPF33I outputs a signal obtained by removing a relatively high frequency component from the signal to the analog signal processing circuit 41 as a baseband signal Dbi on the I channel side. Further, the signal frequency-converted by the mixer 32Q is input to the LPF33Q. The LPF33Q outputs a signal obtained by removing a relatively high frequency component from the signal to the control circuit 152 as a baseband signal Dbq on the Q channel side. The baseband signals Dbi and Dbq are output as Doppler signals that have undergone Doppler shift due to the body movement of the living body P, respectively.

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

(Control circuit 152)
FIG. 4 is a block diagram for explaining the configuration of the control circuit 152 according to the first embodiment. The control circuit 152 includes an analog signal processing circuit 41, an AD converter 43, and a microprocessor 45. Typically, the microprocessor 45 is a digital signal processor (DSP) specialized in digital signal processing. In another aspect, the control circuit 152 may be configured to include a microcontroller instead of the microprocessor 45.

The analog signal processing circuit 41 removes unnecessary frequency band components from the signal input from the Doppler sensor 40 and outputs the signal to the AD converter 43. Specifically, the analog signal processing circuit 41 outputs the I-channel analog signal Shi and the Q-channel analog signal Shq in the heartbeat component band (0.7 Hz to 20 Hz), and outputs the body movement component band (0.1 Hz). ~ 40Hz) I-channel analog signal Sti and Q-channel analog signal Stq are output. The band of the body movement component also includes the band of the respiratory component. A specific configuration of the analog signal processing circuit 41 will be described with reference to FIG.

<Analog signal processing circuit 41>
FIG. 5 is a block diagram showing an example of the configuration of the analog signal processing circuit 41 according to the first embodiment.

With reference to FIG. 5, the analog signal processing circuit 41 receives the I-channel side baseband signal Dbi output from the Doppler sensor 40 and the Q-channel side baseband signal Dbq output from the Doppler sensor 40 as inputs. receive. The baseband signal Dbi is distributed to the analog signals Dbia and Dbib. The baseband signal Dbq is distributed to the analog signals Dbqa and Dbqb.

The analog signal processing circuit 41 includes signal processing circuits 149A to 149D. The analog signal Dbia is output to the signal processing circuit 149A for heart rate measurement. The signal processing circuit 149A includes HPF143A, LFP144A, and amplifier 145A.

HPF143A removes the low frequency components of the analog signal Dbia. As an example, HPF143A removes signal components below 0.8 Hz. The removed signal is output to the LFP144A.

The LFP144A removes the high frequency component of the analog signal Dbia output from the HPF143A. As an example, LFP144A removes signal components above 20 Hz. The removed signal is output to the amplifier 145A.

The amplifier 145A amplifies the analog signal Dbia output from the LFP144A by a predetermined time (for example, 400 times) to generate the analog signal Shi. The analog signal Shi is output to the AD converter 43 (see FIG. 4) described above.

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

HPF143B removes the low frequency components of the analog signal Dbib. As an example, HPF143B removes signal components below 0.1 Hz. The removed signal is output to the LFP144B.

The LFP144B removes the high frequency component of the analog signal Dbib output from the HPF143B. As an example, LFP144B removes signal components above 20 Hz. The removed signal is output to the amplifier 145B.

The amplifier 145B amplifies the analog signal Dbib output from the LFP144B by a predetermined time (for example, 100 times) to generate the analog signal Sti. The analog signal Sti is output to the AD converter 43 (see FIG. 4) described above.

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

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

HPF143C removes the low frequency component of the analog signal Dbqa. As an example, HPF143C removes signal components below 0.8 Hz. The removed signal is output to the LFP144C.

The LFP144C removes the high frequency component of the analog signal Dbqa output from the HPF143C. As an example, LFP144C removes signal components above 20 Hz. The removed signal is output to the amplifier 145C.

The amplifier 145C amplifies the analog signal Dbqa output from the LFP144C by a predetermined time (for example, 400 times) to generate the analog signal Shq. The analog signal Shq is output to the AD converter 43 (see FIG. 4) described above.

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

HPF143D removes the low frequency component of the analog signal Dbqb. As an example, HPF143D removes signal components below 0.1 Hz. The removed signal is output to the LFP144D.

The LFP144D removes the high frequency component of the analog signal Dbqb output from the HPF143D. As an example, LFP144D removes signal components above 20 Hz. The removed signal is output to the amplifier 145D.

The amplifier 145D amplifies the analog signal Dbqb output from the LFP 144D by a predetermined time (for example, 100 times) to generate the analog signal Stq. The analog signal Stq is output to the AD converter 43 (see FIG. 4) described above. The analog signal Ti and the analog signal Stq function as body motion signals related to the movement of the living body P. In this sense, it can be said that the analog signal processing circuit 41 extracts the body motion signal as an analog signal from the Doppler signal.

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

HPF143A to 143D and LFP144A to 144D are, for example, active filters using operational amplifiers. Alternatively, HPF 143A to 143D may be passive elements using the coil L, the capacitor C, and the resistor R.

As described above, by independently performing band limitation and amplification for amplitude measurement and respiration measurement, a high-quality analog signal having a high SN (Signal Noise) ratio is extracted in the heartbeat range and the respiration range. LFP144A to 144D also function as an antialiasing filter for the AD converter 43 described above.

With reference to FIG. 4 again, the AD converter 43 performs 16-bit (or 12-bit) AD conversion of the input signal. Specifically, the AD converter 43 receives the inputs of the analog signals Shi, Shq, Ti, and Stq, and converts the analog signals Shi, Shq, Sti, and Stq into digital signals at a predetermined sampling rate (for example, 100 Hz). And output to the microprocessor 45. The digital signals Shi, Shq, Ti, and Stq are appropriately offset-adjusted as signals according to the voltage amplitude.

<Microprocessor 45>
The microprocessor 45 executes various processes using each digital signal Shi, Shq, Ti, Stq. Specifically, the microprocessor 45 includes a motion detection unit 50, an output unit 52, a heart rate calculation unit 60, and a respiration calculation unit 70 as main functional configurations.

≪Heart rate calculation unit 60≫
The heart rate calculation unit 60 receives the inputs of the digital signals Shi and Shq and executes various processes. Specifically, the heart rate calculation unit 60 includes a low-pass filter (LPF) 62I, a high-pass filter (HPF) 63I, a heart rate detection unit 65I, and a comparison unit 66I on the I channel side, and LPF 62Q, HPF 63Q, and heart rate on the Q channel side. It has a number detection unit 65Q and a comparison unit 66Q. The heart rate calculation unit 60 further includes an amplitude threshold value confirmation unit 64 common to the I channel and the Q channel, and a median processing unit 67.

The LPF62I and 62Q generate digital signals Hai and Haq by removing high-frequency components of the digital signals Shi and Shq, respectively. The LPF62I and 62Q output the generated digital signals Hai and Haq to the HPF63I and 63Q, respectively. Hereinafter, LPF62I and 62Q are also collectively referred to as LPF62. As an example, the cutoff frequency of LPF62 is set to 20 Hz. This is intended to detect up to the 10th harmonic (20 Hz) of the heartbeat waveform even when the heart rate of the living body P is high (for example, 2 Hz (120 bpm)). The cutoff frequency of the LFP 62 may be manually switchable or may be automatically switchable according to the heart rate of the living body P.

HPF63I and 63Q generate digital signals Hbi and Hbq by removing low frequency components (particularly, respiratory component bands) of the digital signals Hai and Haq, respectively. The HPF63I and 63Q output the generated digital signals Hbi and Hbq to the amplitude threshold value confirmation unit 64. Hereinafter, HPF63I and 64Q are also collectively referred to as HPF63. As an example, the cutoff frequency of HPF63 is set to 0.8 Hz. The cutoff frequency of the HFP 63 may be manually switchable or may be automatically switchable according to the heart rate of the living body P.

The amplitude threshold value confirmation unit 64 determines whether the input digital signals Hbi and Hbq are heartbeat signals or noise. Hereinafter, the digital signals Hbi and Hbq are also collectively referred to as digital signals Hb. First, the amplitude threshold value confirmation unit 64 detects the amplitude of the digital signal Hb.

As an example, the amplitude threshold value confirmation unit 64 calculates the square root of the sum of the square values of the amplitude values of the digital signals Hbi and Hbq as the amplitude value of the digital signal Hb. Specifically, the value calculated by the following equation (1) or equation (2) is calculated as the amplitude value of the digital signal Hb.
(Hbi x Hbi + Hbq x Hbq) ^ (1/2) ... (1)
((Hbi x Hbi + Hbq x Hbq) / 2) ^ (1/2) ... (2)
Hereinafter, the value calculated by the same method as in (1) or (2) above is also referred to as "IQ root mean square value". When the amplitude value of the digital signal Hb is less than the preset threshold value Ath1, the amplitude threshold value confirmation unit 64 determines that the digital signal Hb is noise. On the other hand, when the amplitude value of the digital signal Hb is equal to or higher than the threshold value Ath1, the amplitude threshold confirmation unit 64 determines that the digital signal Hb is a heartbeat signal, and sends the digital signals Hbi and Hbq to the heart rate detection units 65I and 65Q. Output each.

The threshold value Ath1 is set in advance before detecting the biological information of the living body P. As an example, the measuring device 100 calculates the amplitude values of the digital signals Hbi and Hbq in advance in a situation where there is no moving object (including the living body P) in the surroundings. The measuring device 100 calculates the IQ squared average value of the amplitude values of the digital Hbi and Hbq in the same manner as in the above method. The measuring device 100 sets the threshold value Ath1 so that the value is equal to or higher than the average value. As an example, the measuring device 100 sets 1.2 times the average value as the threshold value Ath1.

In another aspect, the measuring device 100 measures the IQ squared average value of the amplitude values of the digital Hbi and Hbq a plurality of times over a predetermined time (for example, 5 seconds) in a situation where there is no moving object in the surroundings, and a plurality of the measured values are measured. Calculate the average value of the values. The measuring device 100 may set 1.2 times the calculated average value as the threshold value Ath1. The measuring device 100 stores the threshold value Ath1 in the memory 154. As an example, the measuring device 100 may be configured to set the threshold value Ath1 when the power is turned on, or may be configured to set the threshold value Ath1 based on the input of the user.

The measuring device 100 according to the first embodiment suppresses the detection of an erroneous heart rate from the noise by determining whether or not the digital signal Hb is noise by the amplitude threshold value confirmation unit 64.

The heart rate detection units 65I and 65Q detect the heart rate using the digital signals Hbi and Hbq, respectively. Specifically, the heart rate detection unit 65I performs a fast Fourier transform (FFT) on the digital signal Hbi accumulated for a predetermined time (for example, 5 seconds), decomposes it into individual signal components, and then decomposes each component into individual signal components. Is performed on the frequency spectrum to create frequency distribution data. The heart rate detection unit 65I detects the frequency component having the highest intensity (peak frequency component) among the frequency distribution data as the fundamental wave data. The heart rate detection units 65I and 65Q may be configured to detect fundamental wave data by using an autocorrelation function or a wavelet transform.

The heart rate detection unit 65I detects the heart rate Hi by multiplying the fundamental wave data by 60. Similarly, the heart rate detection unit 65Q detects the heart rate Hq using the digital signal Hbq. The heart rate detection units 65I and 65Q output the detected heart rate Hi and Hq to the comparison units 66I and 66Q, respectively.

The comparison units 66I and 66Q determine whether the input heart rate is due to the heart rate signal or noise. Specifically, the comparison unit 66I compares the input heart rate Hi with the past heart rate (hereinafter, also referred to as “old heart rate”) stored in the history area 155 of the memory 154, and the comparison result. When the predetermined condition is satisfied, it is determined that the input heart rate Hi is caused by the heart rate signal rather than the noise. As an example, the old heart rate is the newest heart rate stored in the history area 155 (ie, the previously detected heart rate). The old heart rate may be the past heart rate Hi or the average value of the past heart rates Hi and Hq. The predetermined conditions include, for example, that the volatility of the input heart rate Hi with respect to the old heart rate is within a predetermined range (for example, ± 10%).

When the comparison unit 66I determines that the input heart rate Hi is due to the heart rate signal, the comparison unit 66I outputs the heart rate Hi to the median processing unit 67. On the other hand, when the comparison unit 66I determines that the input heart rate Hi is caused by noise, the comparison unit 66I outputs the old heart rate to the median processing unit 67 instead of the heart rate Hi. The comparison unit 66Q also outputs the input heart rate Hq or the old heart rate to the median processing unit 67 in the same manner as the comparison unit 66I.

The median processing unit 67 calculates the average heart rate by averaging the two heart rates of the I channel and the Q channel input from the comparison units 66I and 66Q. The calculated average heart rate is stored in a predetermined number (for example, 4) in the memory 154. The median processing unit 67 identifies the median heart rate Hn from the calculated average heart rate and a predetermined number of average heart rates stored in the memory. The median processing unit 67 outputs the specified heart rate Hn to the output unit 52. In another aspect, the heart rate calculation unit 60 may be configured to output the new heart rate or the old heart rate from the comparison units 66I and 66Q to the output unit 52 without having the median processing unit 67. Although the median value is used here, it may be the average value of the predetermined number or the moving average of the predetermined number of old heart rate and new heart rate.

According to the above, in the measuring device 100 according to the first embodiment, the noise caused by the movement of the body of the living body P or the noise caused by the harmonics of the respiratory waveform (particularly the third harmonic) due to the action of the comparison units 66I and 66Q. It is possible to suppress the erroneous detection of the heart rate of the living body P from the above.

≪Breathing calculation unit 70≫
The respiration calculation unit 70 receives the inputs of the digital signals Sti and Stq and executes various processes. Specifically, the respiratory calculation unit 70 has an LPF72I, a respiratory rate detection unit 75I, and a comparison unit 76I on the I channel side, and an LPF72Q, a respiratory rate detection unit 75Q, and a comparison unit 76Q on the Q channel side. The respiration calculation unit 70 further includes an amplitude threshold value confirmation unit 74 common to the I channel and the Q channel, and a median processing unit 77.

LPF72I and 72Q generate digital signals Bai and Baq by removing high frequency components (particularly, the band of the heart component) of the digital signals Sti and Stq, respectively. The LPF72I and 72Q output the generated digital signals Bai and Baq to the amplitude threshold value confirmation unit 74. Hereinafter, LPF72I and 72Q are also collectively referred to as LPF72. As an example, the cutoff frequency of LPF72 is set to 0.7 Hz. The cutoff frequency of the LFP72 may be manually switchable or may be automatically switchable according to the heart rate of the living body P.

The amplitude threshold confirmation unit 74 determines whether the input digital signals Bai and Baq are respiratory signals or noise. Hereinafter, the digital signals Bai and Baq are also collectively referred to as digital signals Ba. First, the amplitude threshold value confirmation unit 74 detects the amplitude of the digital signal Ba.

As an example, the amplitude threshold value confirmation unit 74 calculates the IQ squared average value of the amplitude values of the digital signals Bai and Baq as the amplitude value of the digital signal Ba. When the amplitude value of the digital signal Ba is less than the preset threshold value Ath2, the amplitude threshold value confirmation unit 74 determines that the digital signal Ba is noise. On the other hand, when the amplitude value of the digital signal Ba is equal to or higher than the threshold Ath2, the amplitude threshold confirmation unit 74 determines that the digital signal Ba is a respiratory signal, and sends the digital signals Bai and Baq to the respiratory rate detection units 75I and 75Q. Output each.

The threshold value Ath2 is set in advance before detecting the biological information of the living body P. As an example, the measuring device 100 calculates the amplitude values of the digital signals Bai and Baq in advance in a situation where there is no moving object in the surroundings. The measuring device 100 calculates the IQ squared average value of the amplitude values of the digital signals Bai and Baq. The measuring device 100 sets the threshold value Ath2 so that the value is equal to or higher than the average value. As an example, the measuring device 100 sets 1.2 times the amplitude value as the threshold value Ath2.

In another aspect, the measuring device 100 measures the IQ squared average value of the amplitude values of the digital signals Bai and Baq a plurality of times over a predetermined time (for example, 5 seconds) in a situation where there is no moving object in the surroundings, and the plurality of measurements are performed. Calculate the average value of. The measuring device 100 may set 1.2 times the calculated average value as the threshold value Ath2. The measuring device 100 stores the threshold value Ath2 in the memory 154. As an example, the measuring device 100 may be configured to set the threshold value Ath2 when the power is turned on, or may be configured to set the threshold value Ath2 based on the input of the user.

The measuring device 100 according to the first embodiment suppresses the detection of an erroneous respiratory rate from the noise by determining whether or not the digital signal Ba is noise by the amplitude threshold value confirmation unit 74.

The respiratory rate detection units 75I and 75Q detect the respiratory rate using the digital signals Bai and Baq, respectively. Specifically, the respiratory rate detection unit 75I performs a fast Fourier transform on the digital signal Bai accumulated for a predetermined time (for example, 10 seconds), decomposes it into individual signal components, and then displays each component on the frequency spectrum. To create frequency distribution data. The respiratory rate detection unit 75I detects the frequency component (peak frequency component) having the highest intensity among the frequency distribution data as the fundamental wave data. The respiratory rate detection units 75I and 75Q may be configured to detect fundamental wave data by using an autocorrelation function or a wavelet transform.

The respiratory rate detection unit 75I detects the respiratory rate Bi by multiplying the fundamental wave data by 60. Similarly, the respiratory rate detection unit 75Q detects the respiratory rate Bq using the digital signal Baq. The respiratory rate detection units 75I and 75Q output the detected respiratory rate Bi and Bq to the comparison units 76I and 76Q, respectively.

The comparison units 76I and 76Q determine whether the input respiratory rate is due to the respiratory signal or noise. Specifically, the comparison unit 76I compares the input respiratory rate Bi with the past respiratory rate (hereinafter, also referred to as “old respiratory rate”) stored in the history area 155 of the memory 154, and the comparison result. When the predetermined condition is satisfied, it is determined that the input respiratory rate Bi is caused by the respiratory signal rather than the noise. As an example, the old respiratory rate is the newest respiratory rate (ie, the previously detected respiratory rate) stored in the history area 155. The old respiratory rate may be the past respiratory rate Bi or the average value of the past respiratory rates Bi and Bq. The predetermined conditions include, for example, that the volatility of the input respiratory rate Bi with respect to the old respiratory rate is within a predetermined range (for example, ± 20%).

When the comparison unit 76I determines that the input respiratory rate Bi is caused by the respiratory signal, the comparison unit 76I outputs the respiratory rate Bi to the median processing unit 77. On the other hand, when the comparison unit 76I determines that the input respiratory rate Bi is caused by noise, the comparison unit 76I outputs the old respiratory rate to the median processing unit 77 instead of the respiratory rate Bi. The comparison unit 76Q also outputs the input respiratory rate Bq or the old respiratory rate to the median processing unit 77 in the same manner as the comparison unit 76I.

The median processing unit 77 calculates the average respiratory rate by averaging the two respiratory rates input from the comparison units 76I and 76Q. The calculated average respiratory rate is stored in a predetermined number (for example, 4) in the memory 154. The median processing unit 77 specifies the respiratory rate Bn, which is the median value, from the calculated average respiratory rate and the predetermined number of average respiratory rates stored in the memory. The median processing unit 77 outputs the specified respiratory rate Bn to the output unit 52. In another aspect, the respiration calculation unit 70 may be configured to output the new respiration rate or the old respiration rate from the comparison units 76I and 76Q to the output unit 52 without having the median processing unit 77. Although the median value is used here, it may be the average value of the predetermined number or the moving average of the predetermined number of old heart rate and new heart rate.

According to the above, the measuring device 100 according to the first embodiment can suppress the erroneous detection of the respiratory rate of the living body P from the noise caused by the movement of the body of the living body P by the action of the comparison units 76I and 76Q.

<< Motion detection unit 50 >>
The motion detection unit 50 detects the body motion (particularly, the body motion) of the living body P based on a predetermined threshold value and reflected signals (specifically, each digital signal Sti, Stq). Specifically, the motion detection unit 50 includes an amplitude detection unit 52I on the I channel side, an amplitude detection unit 52Q on the Q channel side, and an amplitude threshold value confirmation unit 54 common to the I channel and the Q channel.

The amplitude detection unit 52I detects the amplitude Ti of the digital signal Sti and outputs the detection result to the amplitude threshold value confirmation unit 54. The amplitude detection unit 52Q detects the amplitude Tq of the digital signal Stq and outputs the detection result to the amplitude threshold value confirmation unit 54.

The amplitude threshold value confirmation unit 54 calculates the IQ squared average value (hereinafter, also referred to as “body movement amplitude value”) of the input amplitudes Ti and Tq. When the body movement amplitude value is equal to or higher than the preset threshold value Ath3, the amplitude threshold confirmation unit 54 detects that the body of the living body P has moved (for example, the living body P has risen from a sleeping state). On the other hand, the amplitude threshold value confirmation unit 54 does not detect the movement of the body of the living body P when the body movement amplitude value is less than the threshold value Ath3. The amplitude threshold confirmation unit 54 outputs the detection result to the output unit 52.

The threshold value Ath3 is set in advance before detecting the biological information of the living body P. Specifically, the measuring device 100 calculates the IQ squared average value of the amplitude values of the digital signals Ti and Stq in advance in a situation where there is no moving object in the surroundings. The measuring device 100 sets the threshold value Ath3 so that the value is equal to or higher than the average value. As an example, the measuring device 100 sets 1.2 times the average value as the threshold value Ath3.

In another aspect, the measuring device 100 measures the IQ squared average value of the amplitude values of the digital signals Ti and Stq a plurality of times over a predetermined time (for example, 5 seconds) in a situation where there is no moving object in the surroundings, and these measurements are taken. Calculate the average value of multiple values. The measuring device 100 may set 1.2 times the calculated average value as the threshold value Ath3. The measuring device 100 stores the threshold value Ath3 in the memory 154. As an example, the measuring device 100 may be configured to set the threshold value Ath3 when the power is turned on, or may be configured to set the threshold value Ath3 based on the input of the user.

The output unit 52 outputs a body movement detection result by the motion detection unit 50, a heart rate measurement result by the heart rate calculation unit 60, a respiration rate measurement result by the respiration calculation unit 70, and the like. The output mode of these measurement results is arbitrary. In a certain aspect, the output unit 52 outputs warning information when it receives a determination result of a body movement abnormality, a heartbeat abnormality, or a respiratory abnormality. The output unit 52 may output the warning information by voice via the speaker 156, or may display the warning information on the display. Further, the output unit 52 may transmit warning information to the terminal device 200 via the communication interface 158. In another aspect, these measurement results are, for example, digitized according to a predetermined format and then transmitted to the terminal device 200 via the communication interface 158 (see FIG. 3). The terminal device 200 displays the measurement result received from the measuring device 100.

(Control structure of measuring device 100)
The control structure of the measuring device 100 will be described with reference to FIGS. 6 to 8. FIG. 6 is a flowchart showing a heart rate measurement process. FIG. 7 is a flowchart showing the measurement process of the respiratory rate. FIG. 8 is a flowchart showing the body movement detection process. The processes of FIGS. 6 to 8 are realized by executing the program by the microprocessor 45 of the measuring device 100. In other aspects, some or all of the processing may be performed by circuit elements or other hardware. It is assumed that the threshold values Ath1 to Ath3 used in the processes of FIGS. 6 to 8 are measured in advance before each series of processes shown in FIGS. 6 to 8 is executed by the above method. Further, the microprocessor 45 periodically and repeatedly executes each series of processes shown in FIGS. 6 to 8.

<Heart rate measurement processing>
First, the flow of the heart rate measurement process will be described with reference to FIG.

In step S610, the microprocessor 45 receives the input of the I-channel digital signal Shi and the Q-channel digital signal Shq from the AD converter 43 in the heartbeat component band.

In step S620, the microprocessor 45 removes the signal component included in the cutoff band set in the LPF62I from the digital signal Shi on the I channel side. Further, the microprocessor 45 removes the signal component included in the cutoff band set in the LPF62Q from the digital signal Shq on the Q channel side.

In step S630, the microprocessor 45 removes the signal component included in the cutoff band set in the HPF63I from the digital signal Shi on the I channel side. Further, the microprocessor 45 removes the signal component included in the cutoff band set in the HPF63Q from the digital signal Shq on the Q channel side. The microprocessor 45 extracts the heartbeat signal as a digital signal through the steps S620 and S630.

In step S640, the microprocessor 45 calculates the amplitude of the extracted heartbeat signal. As an example, the microprocessor 45 calculates the IQ squared average value of the amplitude of the heartbeat signal on the I channel side and the amplitude of the heartbeat signal on the Q channel side. In another aspect, the microprocessor 45 may calculate the average value of the absolute values of these amplitudes, or may be configured to adopt one of these amplitudes. The microprocessor 45 determines whether or not the calculated amplitude of the heartbeat signal is equal to or greater than the threshold value Ath1 stored in the memory 154. When the microprocessor 45 determines that the calculated amplitude of the heartbeat signal is equal to or greater than the threshold value Ath1 (YES in step S640), the microprocessor 45 executes the process of step S650. On the other hand, when the microprocessor 45 determines that the calculated amplitude of the heart rate signal is less than the threshold value Ath1 (NO in step S640), the extracted heart rate signal is noise that does not include a heart rate component, and the heart rate is 0 bpm. It is determined that there is (step S645), and then the process of step S690 is executed.

In step S650, the microprocessor 45 detects the periodicity of the extracted heartbeat signal. Typically, the microprocessor 45 generates frequency distribution data by performing a fast Fourier transform on each of the heartbeat signals on the I channel side and the Q channel side, and based on the frequency components having high signal strength from the frequency distribution data. Detect as wave data. The microprocessor 45 may detect the fundamental wave data by using an autocorrelation function or a wavelet transform. The microprocessor 45 calculates the heart rate per unit time (that is, 1 minute) by multiplying the fundamental wave data by 60 for each of the I channel side and the Q channel side. The microprocessor 45 further averages these heart rates and detects the heart rate as a measurement result. The detected heart rate is also called the "new heart rate".

In step S660, the microprocessor 45 determines whether or not the volatility of the new heart rate with respect to the old heart rate (past heart rate stored in the memory 154) is within a predetermined range. As an example, the predetermined range is set within ± 10%. In one aspect, the old heart rate is the newest heart rate stored in memory 154. In another aspect, the old heart rate is set to the average of the newest plurality of heart rates stored in memory 154.

When the microprocessor 45 determines that the volatility of the new heart rate with respect to the old heart rate is within a predetermined range (YES in step S660), the microprocessor 45 executes the process of step S670. If not (NO in step S660), the microprocessor 45 executes the process of step S680.

In step S670, the microprocessor 45 determines that the new heart rate is not noise and stores the new heart rate in the history area 155 of the memory 154. The microprocessor 45 further identifies the median heart rate from the newest plurality (eg, 5) heart rates (including new heart rates) stored in the history area 155.

In step S680, the microprocessor 45 determines that the new heart rate is noise and stores the old heart rate in the history area 155 of the memory 154. The microprocessor 45 further identifies the median heart rate from the newest plurality (eg, 5) heart rates (not including the new heart rate) stored in the history area 155.

In step S690, the microprocessor 45 outputs the specified median heart rate as a measurement result. The output mode of the measurement result is arbitrary. In a certain aspect, the microprocessor 45 may output the measurement result by voice via the speaker 156 or may be output via the display. Further, the microprocessor 45 may output the measurement result to the terminal device 200 via the communication interface 158. In another aspect, the microprocessor 45 may be configured to determine as a heartbeat abnormality and output warning information when the heart rate is equal to or less than a predetermined lower limit value or greater than or equal to a predetermined upper limit value.

In step S640, the microprocessor 45 calculates one amplitude value (for example, IQ root mean square value) based on the amplitude value of the heartbeat signal on the I channel side and the amplitude value of the heartbeat signal on the Q channel side. Therefore, it is configured to compare the calculated one threshold value with the threshold value Ath1, but the configuration is not limited to this. In another aspect, the microprocessor 45 may be configured to compare the amplitude value of each heartbeat signal on the I-channel side and the Q-channel side with the threshold value Ath1. In such a case, the microprocessor 45 determines that the amplitude values of both the I-channel side and the Q-channel side heartbeat signals exceed the threshold value Ath1, or the amplitude value of either one of the heartbeat signals exceeds the threshold value Ath1. The process of step S650 may be executed.

<Respiratory rate measurement processing>
Next, the flow of the respiratory rate measurement process will be described with reference to FIG. 7.

In step S710, the microprocessor 45 receives the input of the I-channel digital signal Ti and the Q-channel digital signal Stq from the AD converter 43 in the band of the body movement component.

In step S720, the microprocessor 45 removes the signal component included in the cutoff band set in the LPF72I from the digital signal Ti on the I channel side. Further, the microprocessor 45 removes the signal component included in the cutoff band set in the LPF72Q from the digital signal Stq on the Q channel side. As a result, the microprocessor 45 extracts the respiratory signal as a digital signal.

In step S730, the microprocessor 45 calculates the amplitude of the extracted respiratory signal. As an example, the microprocessor 45 calculates the IQ squared average value of the amplitude of the respiratory signal on the I channel side and the amplitude of the respiratory signal on the Q channel side. In another aspect, the microprocessor 45 may calculate the average value of the absolute values of these amplitudes, or may be configured to adopt one of these amplitudes. The microprocessor 45 determines whether or not the calculated amplitude of the respiratory signal is equal to or greater than the threshold value Ath2 stored in the memory 154. When the microprocessor 45 determines that the calculated amplitude of the respiratory signal is equal to or greater than the threshold value Ath2 (YES in step S730), the microprocessor 45 executes the process of step S740. On the other hand, when the microprocessor 45 determines that the calculated respiratory signal amplitude is less than the threshold Ath2 (NO in step S730), the extracted respiratory signal is noise containing no respiratory component, and the respiratory rate is 0 bpm. It is determined that there is (step S735), and then the process of step S780 is executed.

In step S740, the microprocessor 45 detects the periodicity of the extracted respiratory signal. Typically, the microprocessor 45 generates frequency distribution data by performing a fast Fourier transform on each of the respiratory signals on the I channel side and the Q channel side, and based on the frequency components having high signal strength from the frequency distribution data. Detect as wave data. The microprocessor 45 may detect the fundamental wave data by using an autocorrelation function or a wavelet transform. The microprocessor 45 calculates the respiratory rate per unit time (that is, 1 minute) by multiplying the fundamental wave data by 60 for each of the I channel side and the Q channel side. The microprocessor 45 further averages these respiratory rates to detect the respiratory rate as a measurement result. The detected respiratory rate is also called the "new respiratory rate".

In step S750, the microprocessor 45 determines whether or not the fluctuation rate of the new respiratory rate with respect to the old respiratory rate (past respiratory rate stored in the memory 154) is within a predetermined range. As an example, the predetermined range is set within ± 20%. In one aspect, the old respiratory rate is the newest respiratory rate stored in memory 154. In another aspect, the old respiratory rate is set to the average value of the newest plurality of respiratory rates stored in memory 154.

When the microprocessor 45 determines that the volatility of the new respiratory rate with respect to the old respiratory rate is within a predetermined range (YES in step S750), the microprocessor 45 executes the process of step S760. If not (NO in step S750), the microprocessor 45 executes the process of step S770.

In step S760, the microprocessor 45 determines that the new respiratory rate is not noise and stores the new respiratory rate in the history area 155 of the memory 154. The microprocessor 45 further identifies the median respiratory rate from the newest plurality (eg, 3) respiratory rates (including new respiratory rates) stored in the history area 155.

In step S770, the microprocessor 45 determines that the new respiratory rate is noise and stores the old respiratory rate in the history area 155 of the memory 154. The microprocessor 45 further identifies the median respiratory rate from the newest plurality (eg, 3) respiratory rates (excluding new respiratory rates) stored in the history area 155.

In step S780, the microprocessor 45 outputs the specified median respiratory rate as a measurement result. The output mode of the measurement result is arbitrary. In a certain aspect, the microprocessor 45 may output the measurement result by voice via the speaker 156 or may be output via the display. Further, the microprocessor 45 may output the measurement result to the terminal device 200 via the communication interface 158. In another aspect, the microprocessor 45 may be configured to determine as a respiratory abnormality and output warning information when the respiratory rate is equal to or less than a predetermined lower limit value or greater than or equal to a predetermined upper limit value.

In step S730, the microprocessor 45 has one amplitude value (for example, the IQ square of two amplitude values) based on the amplitude value of the breathing signal on the I channel side and the amplitude value of the breathing signal on the Q channel side. The average value) is calculated and the calculated one threshold value is compared with the threshold Ath2, but the configuration is not limited to this. In another aspect, the microprocessor 45 may be configured to compare the amplitude values of the respective respiratory signals on the I-channel side and the Q-channel side with the threshold value Ath2. In such a case, the microprocessor 45 determines that the amplitude values of both the I-channel side and the Q-channel side respiratory signals exceed the threshold value Ath2, or the amplitude value of either one of the respiratory signals exceeds the threshold value Ath2. The process of step S740 may be executed.

<Body movement detection processing>
Next, the flow of the body movement detection process will be described with reference to FIG.

In step S810, the microprocessor 45 receives inputs of the I-channel digital signal Ti and the Q-channel digital signal Stq as body motion signals from the AD converter 43.

In step S820, the microprocessor 45 detects the amplitude of the received body motion signal. As an example, the microprocessor 45 detects the IQ squared average value of the amplitude of the body motion signal on the I channel side and the amplitude of the body motion signal on the Q channel side as the amplitude of the body motion signal. In another aspect, the microprocessor 45 may detect the average value of the absolute values of these amplitudes as the amplitude of the body motion signal.

In step S830, the microprocessor 45 determines whether or not the amplitude of the detected respiratory signal is equal to or greater than the threshold value Ath3 stored in the memory 154. When the microprocessor 45 determines that the amplitude of the detected respiratory signal is equal to or greater than the threshold value Ath3 (YES in step S830), the microprocessor 45 executes the process of step S840. On the other hand, when the microprocessor 45 determines that the amplitude of the detected body motion signal is less than the threshold value Ath3 (NO in step S830), the microprocessor 45 determines that the body motion signal is noise and ends a series of processes.

In step S840, the microprocessor 45 detects that the body of the living body P has moved. As an example, the microprocessor 45 detects the rising of the living body P and the like. The microprocessor 45 further outputs the detection result. The output mode of the detection result is arbitrary. In a certain aspect, when the measuring device 100 is used as a patient monitoring device, the microprocessor 45 outputs that it has detected the patient's rising. This may be output as audio via the speaker 156 or may be output via the display. Further, the microprocessor 45 may transmit warning information to the terminal device 200 via the communication interface 158.

(Summary of Embodiment 1)
As described above, the measuring device 100 according to the first embodiment compares the detected biological information with the past biological information to determine whether the detected biological information is correct biological information or noise. be able to. Therefore, the measuring device 100 according to the embodiment can suppress the detection of inaccurate biological information as compared with the conventional measuring device. More specifically, the measuring device 100 can suppress erroneous detection of the periodicity of the waveform caused by the movement of the body of the living body P as the heart rate or the respiratory rate. Further, the measuring device 100 can suppress erroneous detection of the periodicity of the harmonics of the respiratory waveform as the heart rate. In addition, when the measuring device 100 determines that the heart rate signal or the respiratory signal is noise, the heart rate or the respiratory rate is output as 0 bpm, so that the user of the measuring device 100 determines the presence or absence of a living body or the life or death of the living body. Can be done.

[Embodiment 2]
Although the measuring device 100 according to the first embodiment described above can suppress the detection of inaccurate biometric information, it can detect inaccurate biometric information from noise in some cases. If the correct biometric information is detected after the inaccurate biometric information is detected, the volatility of the correct biometric information with respect to the inaccurate biometric information becomes large. Even though it is information, the biometric information is judged as noise. Hereinafter, a specific configuration and control of the measuring device 100A according to the second embodiment that can solve such a problem will be described.

FIG. 9 is a block diagram for explaining the configuration of the control circuit 152A included in the measuring device 100A according to the second embodiment. The configuration of the measuring device 100 and the configuration of the measuring device 100A are substantially the same. Therefore, in the following, only the portion of the configuration of the measuring device 100A that is different from the configuration of the measuring device 100 will be described.

The control circuit 152A is different from the control circuit 152 according to the first embodiment in that it functions as the heart rate calculation unit 60A and the respiration calculation unit 70A in place of the heart rate calculation unit 60 and the respiration calculation unit 70.

(Heart rate calculation unit 60A)
The heart rate calculation unit 60A differs from the heart rate calculation unit 60 in that it has comparison units 66IA and 66QA instead of comparison units 66I and 66Q, and further has a counter 68. In a certain aspect, the amplitude threshold value confirmation unit 64 outputs a predetermined signal to the counter 68 when at least one of the digital signals Hbi and Hbq is the threshold value Ath1 or more. When the counter 68 receives the input of a predetermined signal from the amplitude threshold value confirmation unit 64, the counter 68 increments the internal count value. Further, when at least one of the digital signals Hbi and Hbq is the threshold value Ath1 or more, at least one of the comparison units 66IA and 66QA executes a comparison process between the new heart rate and the old heart rate. That is, the counter 68 counts the number of times the comparison process is executed (the number of counts is a natural number). In another aspect, the amplitude threshold value confirmation unit 64 may be configured to output a predetermined signal to the counter 68 only when both the digital signals Hbi and Hbq are the threshold values Ath1 or more.

The comparison unit 66IA accesses the counter 68 to check the count value before performing the comparison processing between the new heart rate on the I channel side and the old heart rate on the I channel side described above. When the counter value is a predetermined value (for example, 4), the comparison unit 66IA outputs the new heart rate on the I channel side to the median processing unit 67 without performing the above-mentioned comparison processing. After that, the comparison unit 66IA outputs an initialization signal to the counter 68. The counter 68 initializes (reset) the count value in response to the input of the initialization signal. Similar to the comparison unit 66IA, the comparison unit 66QA also outputs the new heart rate on the Q channel side to the median processing unit 67 without performing the above-mentioned comparison processing when the count value is a predetermined value.

According to the above, the heart rate calculation unit 60A according to the second embodiment omits the comparison process in the comparison units 66IA and 66QA every predetermined number of times (for example, 5 times), and the new heart rate on the I channel side and the new heart rate on the Q channel side. The heart rate Hn is detected using the heart rate. Therefore, even if an inaccurate heart rate Hn based on noise is detected, the heart rate calculation unit 60A sets an upper limit of the number of times that the inaccurate heart rate Hn (old heart rate) continues to be adopted. It can be suppressed to the number of times. That is, the heart rate calculation unit 60A can shorten the time required from the detection of the inaccurate heart rate Hn to the detection of the accurate heart rate Hn as compared with the heart rate calculation unit 60 according to the first embodiment.

(Respiratory calculation unit 70A)
The respiration calculation unit 70A differs from the respiration calculation unit 70 in that it has comparison units 76IA and 76QA instead of comparison units 76I and 76Q, and further has a counter 78. The counter 78 counts the number of times the comparison process is executed in the comparison units 76IA and 76QA (the number of counts is a natural number). Since this counting method is the same as the counting method in the counter 68, it will not be described repeatedly.

The comparison unit 76IA accesses the counter 78 and confirms the count value before performing the comparison processing between the new respiration rate on the I channel side and the old respiration rate on the I channel side described above. When the counter value is a predetermined value (for example, 4), the comparison unit 76IA outputs the new respiratory rate on the I channel side to the median processing unit 77 without performing the above-mentioned comparison processing. After that, the comparison unit 76IA outputs an initialization signal to the counter 78. The counter 78 initializes (reset) the count value in response to the input of the initialization signal. Similar to the comparison unit 76IA, the comparison unit 76QA also outputs the new respiratory rate on the Q channel side to the median processing unit 77 when the count value is a predetermined value without performing the above-mentioned comparison processing.

According to the above, the respiration calculation unit 70A according to the second embodiment omits the comparison processing in the comparison units 76IA and 76QA every predetermined number of times (for example, 5 times), and the new respiratory rate on the I channel side and the new respiration rate on the Q channel side. Respiratory rate Bn is detected using respiratory rate. Therefore, even if an inaccurate respiratory rate Bn based on noise is detected, the respiratory calculation unit 70A sets an upper limit of the number of times that the inaccurate respiratory rate Bn (old respiratory rate) continues to be adopted. It can be suppressed to the number of times. That is, the respiration calculation unit 70A can shorten the time required from the detection of the inaccurate respiration rate Bn to the detection of the accurate respiration rate Bn as compared with the respiration calculation unit 70 according to the first embodiment.

(Heart rate measurement processing)
FIG. 10 is a flowchart showing a heart rate measurement process according to the second embodiment. Of the processes shown in FIG. 10, the same processes as those described above are designated by the same reference numerals. Therefore, the description of the process will not be repeated.

The microprocessor 45 executes the process of step S1010 after detecting the heart rate (new heart rate) in step S650.

In step S1010, the microprocessor 45 determines whether or not the number of times the new heart rate and the old heart rate are compared has reached a predetermined number of times (for example, 4). More specifically, the microprocessor 45 determines whether or not the count value in the counter 68 has reached a predetermined value (for example, 4).

When the microprocessor 45 determines that the number of comparisons has reached a predetermined number (YES in step S1010), after initializing the count value in the counter 68, the comparison process in step S660 is omitted and the comparison process in step S670 is omitted. Execute the process. On the other hand, when it is determined that the number of comparisons has not reached the predetermined number (NO in step S1010), the microprocessor 45 executes the comparison process in step S660 after incrementing the count value in the counter 68.

(Respiratory rate measurement processing)
FIG. 11 is a flowchart showing a respiratory rate measurement process according to the second embodiment. Of the processes shown in FIG. 11, the same processes as those described above are designated by the same reference numerals. Therefore, the description of the process will not be repeated.

The microprocessor 45 executes the process of step S1010 after detecting the respiratory rate (new respiratory rate) in step S740.

In step S1110, the microprocessor 45 determines whether or not the number of times the new respiratory rate and the old respiratory rate are compared has reached a predetermined number of times (for example, 4). More specifically, the microprocessor 45 determines whether or not the count value in the counter 78 has reached a predetermined value (for example, 4).

When the microprocessor 45 determines that the number of comparisons has reached a predetermined number (YES in step S1110), after initializing the count value in the counter 78, the comparison process in step S750 is omitted and the comparison process in step S760 is omitted. Execute the process. On the other hand, when it is determined that the number of comparisons has not reached the predetermined number (NO in step S1110), the microprocessor 45 executes the comparison process in step S750 after incrementing the count value in the counter 78.

(Summary of Embodiment 2)
As described above, the measuring device 100A according to the second embodiment omits the comparison process between the new body information and the old biological information every predetermined number of times (for example, 5 times), outputs the new body information, and outputs the new body information to the memory 154. Record. Therefore, in the measuring device 100A according to the second embodiment, even if inaccurate biometric information based on noise is detected, the upper limit of the number of times that the inaccurate biometric information continues to be adopted is suppressed to the above-mentioned predetermined number of times. Can be done. As a result, the measuring device 100A can shorten the time required from the detection of the inaccurate biometric information to the detection of the accurate biometric information as compared with the measuring device 100 according to the first embodiment.

[Embodiment 3]
When the body of the living body P is moving, the detection accuracy of the biological information of the living body P using the Doppler sensor becomes low. Therefore, the measuring device 100B according to the third embodiment calculates an index (hereinafter, also referred to as “movement index”) indicating the degree of body movement of the living body P, and executes various processes based on the calculated movement index.

The measuring device 100B calculates the ratio (ratio) of the amplitude value of the body motion signal to the amplitude value of the respiratory signal as an example of the motion index. As described above, the amplitude of the respiratory signal is much larger than the amplitude of the heartbeat signal (about 10 times greater). Therefore, when the living body P is not moving, the amplitude of the body movement signal is substantially equal to the amplitude of the respiration signal. That is, when the living body P is not moving, the movement index is approximately 1.0. On the other hand, when the living body P is moving, the amplitude of the body movement signal becomes large. Therefore, when the living body P is moving, the movement index becomes larger than 1.0.

In another aspect, the measuring device 100B records the amplitude of the body motion signal in the state where the living body P is stationary in advance, and uses the ratio (ratio) of the amplitude of the body motion signal to the amplitude as the motion index. It may be configured to calculate.

Hereinafter, with reference to FIGS. 12 and 13, how the detection accuracy of the heart rate changes depending on whether the living body P is moving or not.

FIG. 12 is a diagram for explaining the detection accuracy of the heart rate in a state where the living body P is not moving. FIG. 13 is a diagram for explaining the detection accuracy of the heart rate in a state where the living body P is moving. In FIGS. 12 and 13, the horizontal axis represents time and the vertical axis represents heart rate. In FIGS. 12 and 13, the heart rate of the living body P measured by using the non-contact type Doppler sensor, the pulse rate of the living body P measured by using the contact type pulse oximeter, and the motion index are shown. It is shown. In the following, it is assumed that the heart rate and the pulse rate are equal.

With reference to FIG. 12, the motion index is stable at about 1.05 to 1.10. This means that the body of the living body P hardly moves. In this case, the pulse rate measured using the pulse oximeter and the heart rate measured using the Doppler sensor are substantially the same. That is, when the living body P (body) is not moving, the detection accuracy of the living body information measured by the Doppler sensor is high.

With reference to FIG. 13, the motion index fluctuates greatly in the range of 1.00 to 1.30. This indicates that the body of the living body P is moving. In this case, the pulse rate measured using the pulse oximeter and the heart rate measured using the Doppler sensor are significantly different from each other. That is, when the living body P (body) is moving, the detection accuracy of the biological information measured by the Doppler sensor is low.

Based on the results of FIGS. 12 and 13, the measuring device 100B according to the third embodiment cannot guarantee sufficient detection accuracy of biometric information when the motion index is equal to or higher than a preset threshold value (for example, 1.2). As a result, the Doppler signal is discarded. On the other hand, the measuring device 100B is configured to execute the process of detecting the series of biological information described above when the motion index is less than the threshold value. According to this configuration, the measuring device 100B can improve the detection accuracy of biological information as compared with the measuring device according to the first and second embodiments.

(Measuring device 100B)
FIG. 14 is a block diagram for explaining the configuration of the control circuit 152B included in the measuring device 100B according to the third embodiment. The configuration of the measuring device 100A and the configuration of the measuring device 100B are substantially the same. Therefore, in the following, only the portion of the configuration of the measuring device 100B that is different from the configuration of the measuring device 100A will be described.

The control circuit 152B is a control circuit 152A according to the second embodiment in that it functions as a motion detection unit 50B, a heart rate calculation unit 60B, and a respiration calculation unit 70B in place of the motion detection unit 50, the heart rate calculation unit 60A, and the respiration calculation unit 70A. It's different.

Further, the memory 154 according to the third embodiment stores the accuracy tables 1500 and 1600 shown in FIGS. 15 and 16.

FIG. 15 shows an example of the data structure of the accuracy table 1500. The accuracy table 1500 holds the range of motion indicators and the accuracy of the detected heart rate in association with each other. In the example shown in FIG. 15, the accuracy of the heart rate detected when the motion index is 1.05 or less is high, and the heart rate detected when the motion index is 1.06 to 1.10. The accuracy is moderate, and the heart rate detected when the motion index is 1.11 or higher is low.

FIG. 16 shows an example of the data structure of the accuracy table 1600. The accuracy table 1600 holds the range of motion indicators and the accuracy of the detected respiratory rate in association with each other. In the example shown in FIG. 16, the accuracy of the respiratory rate detected when the motion index is 1.15 or less is high, and the respiratory rate detected when the motion index is 1.16 to 1.30. The accuracy is moderate and the respiratory rate detected when the motion index is 1.31 or higher is low.

As described above, the amplitude of the heartbeat signal is much smaller than the amplitude of the respiratory signal. Therefore, as shown in FIGS. 15 and 16, the influence of the body movement of the living body P on the detection of the heartbeat signal is larger than the influence of the body movement of the living body P on the detection of the respiratory signal.

In the above example, the accuracy of the heart rate is set to 3 levels, but in other aspects, the accuracy of the heart rate may be set to 2 levels or 4 levels or more. Similarly, the accuracy of the respiratory rate may be set to 2 levels or 4 levels or more.

(Motion detection unit 50B)
With reference to FIG. 14 again, the motion detection unit 50B differs from the motion detection unit 50 in that it further includes a ratio calculation unit 55, a ratio determination unit 56, and an accuracy determination unit 57. The heart rate calculation unit 60B is different from the heart rate calculation unit 60A in that it has the comparison units 66IB and 66QB in place of the comparison units 66IA and 66QA. The respiration calculation unit 70B is different from the respiration calculation unit 70A in that it has the amplitude threshold confirmation unit 74B and the comparison units 76IB, 76QB in place of the amplitude threshold confirmation unit 74 and the comparison units 76IA and 76QA.

The ratio calculation unit 55 receives the amplitude Ti of the body motion signal Sti on the I channel side from the amplitude detection unit 52I. Further, the ratio calculation unit 55 receives the amplitude Bii of the respiratory signal Bai on the I channel side from the amplitude threshold value confirmation unit 74B.

The ratio calculation unit 55 calculates the ratio (ratio) of the amplitude Ti to the amplitude Bii, that is, the motion index. The ratio calculation unit 55 outputs the calculated ratio to the ratio determination unit 56 and the accuracy determination unit 57.

The ratio determination unit 56 compares the input ratio with the predetermined threshold values Ath4 and Ath5. The threshold value Ath4 is a value for ensuring the detection accuracy of the heart rate, and is set to 1.10 as an example. The threshold value Ath5 is a value for ensuring the detection accuracy of the respiratory rate, and is set to 1.30 as an example. It is assumed that these threshold values Ath4 and Ath5 are stored in the memory 154.

The ratio determination unit 56 outputs the determination result of whether or not the input ratio (movement index) is the threshold value Ath4 or less to the comparison units 66IB and 66QB of the heart rate calculation unit 60B. When the ratio is equal to or less than the threshold value Ath4, the comparison unit 66IB outputs the new heart rate on the I channel side to the median processing unit 67. On the other hand, when the ratio is larger than the threshold value Ath4, the comparison unit 66IB outputs the old heart rate on the I channel side to the median processing unit 67. The comparison unit 66QB also operates in the same manner as the comparison unit 66IB.

The ratio determination unit 56 outputs the determination result of whether or not the input ratio (movement index) is the threshold value Ath5 or less to the comparison units 76IB and 76QB of the respiration calculation unit 70B, respectively. When the ratio is equal to or less than the threshold value Ath5, the comparison unit 76IB outputs the new respiratory rate on the I channel side to the median processing unit 77. On the other hand, when the ratio is larger than the threshold value Ath5, the comparison unit 76IB outputs the old respiratory rate on the I channel side to the median processing unit 77. The comparison unit 76QB also operates in the same manner as the comparison unit 76IB.

The accuracy determination unit 57 outputs the accuracy of the detected heart rate and the accuracy of the detected respiratory rate to the output unit 52 based on the input ratio (movement index). More specifically, the accuracy determination unit 57 refers to the accuracy table 1500 stored in the memory 154 and outputs the accuracy (accuracy of the detected heart rate) corresponding to the input ratio. Output to 52. Further, the accuracy determination unit 57 refers to the accuracy table 1600 stored in the memory 154 and outputs the accuracy (accuracy of the detected respiratory rate) corresponding to the input ratio to the output unit 52. ..

The output unit 52 outputs the accuracy of the heart rate and the accuracy of the respiratory rate input from the accuracy determination unit 57. For example, the output unit 52 may output these accuracy as audio through the speaker 156, or may output them to a display (not shown). Further, the output unit 52 may output these accuracy to the terminal device 200 via the communication interface 158.

In the above example, the ratio calculation unit 55 is configured to calculate the ratio of the amplitude of the body movement signal on the I channel side to the amplitude of the respiratory signal on the I channel side, but the calculation method is limited to this. I can't. For example, the ratio calculation unit 55 may be configured to calculate the ratio of the amplitude of the body motion signal on the Q channel side to the amplitude of the respiratory signal on the Q channel side. Further, the ratio calculation unit 55 uses the amplitude of the body motion signal on the I channel side and the body motion signal on the Q channel side with respect to the IQ root mean square value of the amplitude of the breath signal on the I channel side and the amplitude of the breath signal on the Q channel side. It may be configured to calculate the ratio of the mean squared IQ to the amplitude of.

(Heart rate measurement processing)
FIG. 17 is a flowchart showing a heart rate measurement process according to the third embodiment. Of the processes shown in FIG. 17, the same processes as those described above are designated by the same reference numerals. Therefore, the description of the process will not be repeated.

After detecting the new heart rate (step S650), the microprocessor 45 calculates a motion index (for example, the ratio of the amplitude of the body motion signal to the amplitude of the respiratory signal) as the motion detection unit 50B (step S1710).

In step S1720, when the microprocessor 45 determines that the number of times the new heart rate and the old heart rate are compared has not reached the predetermined number of times (NO in step S1010), whether or not the motion index is the threshold value Ath4 or less. To judge. When the microprocessor 45 determines that the motion index is equal to or less than the threshold value Ath4 (YES in step S1720), the microprocessor 45 executes the comparison process in step S660. On the other hand, when the microprocessor 45 determines that the motion index is larger than the threshold value Ath4 (NO in step S1720), the microprocessor 45 discards the new heart rate detected in step S650 and uses the old heart rate to measure the heart rate Hn. (Step S680).

In step S1730, the microprocessor 45 outputs the specified median heart rate Hn as a measurement result.

According to the above, the measuring device 100B according to the third embodiment has a detected heart rate when the body movement of the living body P is large, that is, when the detection accuracy of the detected heart rate (new heart rate) is low. The heart rate Hn as a measurement result is specified by using the old heart rate without using. As a result, the measuring device 100B can improve the detection accuracy of the heart rate as compared with the measuring device according to the first and second embodiments.

(Respiratory rate measurement processing)
FIG. 18 is a flowchart showing a respiratory rate measurement process according to the third embodiment. Of the processes shown in FIG. 18, the same processes as those described above are designated by the same reference numerals. Therefore, the description of the process will not be repeated.

In step S730, the microprocessor 45 outputs the calculated amplitude of the respiration signal to the motion detection unit 50B as the respiration calculation unit 70B.

After detecting the new respiratory rate (step S740), the microprocessor 45 calculates a motion index (for example, the ratio of the amplitude of the body motion signal to the amplitude of the respiratory signal) as the motion detection unit 50B (step S1810).

In step S1820, when the microprocessor 45 determines that the number of times the new respiratory rate and the old respiratory rate are compared has not reached the predetermined number (NO in step S1110), the calculated motion index is the threshold value Ath5 or less. Judge whether or not. When the microprocessor 45 determines that the motion index is equal to or less than the threshold value Ath5 (YES in step S1820), the microprocessor 45 executes the comparison process in step S750. On the other hand, when the microprocessor 45 determines that the motion index is larger than the threshold value Ath5 (NO in step S1820), the microprocessor 45 discards the new respiratory rate detected in step S740 and uses the old respiratory rate to measure the respiratory rate Bn. (Step S770).

In step S1830, the microprocessor 45 outputs the specified median respiratory rate Bn as a measurement result.

According to the above, the measuring device 100B according to the third embodiment has a detected respiratory rate when the body movement of the living body P is large, that is, when the detection accuracy of the detected respiratory rate (new respiratory rate) is low. The respiratory rate Bn as a measurement result is specified by using the old respiratory rate without using. As a result, the measuring device 100B can improve the accuracy of detecting the respiratory rate as compared with the measuring device according to the first and second embodiments.

(Body movement detection processing)
FIG. 19 is a flowchart showing a body movement detection process according to the third embodiment. Of the processes shown in FIG. 19, the same processes as those described above are designated by the same reference numerals. Therefore, the description of the process will not be repeated.

In step S1910, the microprocessor 45 acquires the amplitude value of the respiration signal from the respiration calculation unit 70B as the motion detection unit 50B.

In step S1920, the microprocessor 45 calculates the ratio (ratio) of the amplitude value of the body motion signal to the amplitude value of the respiratory signal as an example of the motion index. It should be noted that these amplitude values were acquired at substantially the same timing. The microprocessor 45 further outputs the calculated motion index as the motion detection unit 50B to the comparison units 66IA and 66QA of the heart rate calculation unit 60B and the comparison units 76IA and 76QA of the respiration calculation unit 70B.

The amplitude values of the respiratory signal and the body motion signal are the average values of the IQ squared average values of the I channel and Q channel signals (breathing signal or body motion signal) measured over a predetermined time (for example, 5 seconds). However, the calculation method is not limited to this. For example, the microprocessor 45 measures the amplitude value (absolute value) of either the I channel or Q channel signal (breathing signal or body motion signal) over a predetermined time, and measures the average value of the amplitude value (breathing signal or body motion signal) over a predetermined time. It may be calculated as an amplitude value of. As yet another example, the microprocessor 45 manipulates (integrates) the IQ root mean square value of the body motion signal measured over a predetermined time with respect to the sum (integral value) of the IQ root mean square values of the respiratory signals measured over a predetermined time. The ratio of value) may be calculated as a motion index.

In step S1930, the microprocessor 45 refers to the accuracy tables 1500, 1600 stored in the memory 154 to identify the accuracy of the heart rate and the accuracy of the respiratory rate with respect to the calculated motion index.

In step S1940, the microprocessor 45 outputs the accuracy of the specified heart rate and the accuracy of the respiratory rate in addition to the presence or absence of body movement of the living body P. This output mode is arbitrary. In a certain aspect, the microprocessor 45 may output the above contents as audio through the speaker 156 or may output the contents via the display. Further, the microprocessor 45 may transmit the above contents to the terminal device 200 via the communication interface 158.

According to the above, when the measuring device 100B according to the third embodiment outputs the heart rate or the respiratory rate, the accuracy of the heart rate or the respiratory rate is also output. Therefore, the user of the measuring device 100B (for example, the living body P or the observer of the living body P) can easily recognize the reliability of the output heart rate or respiratory rate.

(Summary of Embodiment 3)
As described above, the measuring device 100B according to the third embodiment has a motion detecting unit 50B for calculating a motion index (for example, a ratio (ratio) of the amplitude value of the body motion signal to the amplitude value of the respiratory signal). The measuring device 100B can exclude or abandon unreliable biometric information (for example, heart rate and respiratory rate) based on the calculated motion index, and adopt highly reliable biometric information acquired in the past. In addition, the measuring device 100B can output the biological information and the accuracy of the biological information to the user of the measuring device together. Therefore, the user can easily understand how accurate the output biometric information is.

[Constitution]
The technical features of the present disclosure described above can be summarized as follows.

(Structure 1) According to a certain embodiment, a measuring device for measuring biological information is provided. This measuring device irradiates a living body with microwaves, receives the reflected waves of the microwaves, and outputs a Doppler signal based on the microwaves and the reflected waves, and a Doppler sensor 40 based on the Doppler signal. It includes a control circuit for detecting biological information including at least one of the heart rate and the respiratory rate of the living body, and a memory 154 for storing the detected biological information. The control circuit is a comparison unit 66 (comparison unit 66I, 66IA, 66IB, 66Q, 66QA) that compares the detected biological information (newborn information) with the past biological information (old biological information) stored in the memory 154. , 66QB) and biometric information (neonatal information) detected when the comparison result meets predetermined conditions, or biometric information derived based on the biometric information and past biometric information (center). It includes an output unit 52 that outputs a value).

According to this configuration, the measuring device discards the biological information that does not satisfy the comparison result with the past biological information as noise, so that it is possible to suppress the detection of inaccurate biological information.

(Structure 2) In (Structure 1), the comparison unit 66 is configured to compare the detected biometric information with the latest biometric information stored in the memory 154.

Biological information (particularly heart rate and respiratory rate) does not fluctuate rapidly in a short period of time at rest. By adopting the configuration 2, the measuring device can determine whether or not the new body information is noise based on the comparison result between the new body information acquired in a short period of time and the old biological information. As a result, the measuring device can accurately determine whether or not the new body information is noise.

(Structure 3) In (Structure 1) or (Structure 2), the output unit 52 determines in advance the volatility of the detected biometric information (newborn information) with respect to the biometric information (old biometric information) stored in the memory 154. It is configured to output the detected biometric information or the derived biometric information when it is within the specified range.

(Structure 4) In any of (Structure 1) to (Structure 3), the control circuit has executed the process of comparing the biometric information detected by the comparison unit with the past biometric information stored in the memory 154. Also includes a counter 68 (78) for counting. The comparison unit 66 is further configured to stop the comparison process when the counted number of times is a predetermined number of times.

According to this configuration, even if an inaccurate biometric information is detected, the measuring device can quickly detect the accurate biometric information thereafter.

(Structure 5) In any of (Structure 1) to (Structure 4), the control circuit includes an analog signal processing circuit 41 (signal processing circuits 149B and 149D) that extracts a body motion signal related to the movement of a living body from a Doppler signal. , Calculation of the ratio of the analog signal processing circuit 41 (signal processing circuits 149B and 149D) and LPF72 that extract the respiratory signal related to the breathing of the living body from the Doppler signal, and the amplitude of the body motion signal and the amplitude of the respiratory signal. Further includes a part 55 and the like.

(Structure 6) In (Structure 5), the memory 154 further stores the accuracy tables 1500 and 1600 showing the correspondence between the ratio and the accuracy of the detected biological information. The output unit 52 is configured to output the accuracy corresponding to the ratio based on the correspondence relationship (that is, the accuracy of the detected biological information) together with the detected biological information or the derived biological information. ..

According to this configuration, the user of the measuring device (living body or an observer of the living body) can easily recognize the accuracy of the biological information output by the measuring device.

(Structure 7) In (Structure 5), the output unit 52 outputs the detected biometric information or the derived biometric information when the calculated ratio (motion index) is equal to or less than a predetermined threshold value. It is configured as follows.

According to this configuration, the measuring device abandons and does not output the detected biological information when the movement of the body of the living body is large, that is, when the detection accuracy of the detected biological information is low. Thereby, this measuring device can improve the detection accuracy of biological information.

(Structure 8) The measuring device according to any one of (Structure 1) to (Structure 7) further includes a communication interface 158 for communicating with the terminal device 200. The output unit 52 is configured to output the biometric information detected or derived biometric information via the communication interface 158 to the terminal device 200.

According to this configuration, the user of the terminal device 200 can easily recognize the detected biometric information.

The various processes described above are realized by the microprocessor 45 of the control circuit 152 executing the measurement program stored in the memory 154. In other aspects, some or all of the processing may be performed by circuit elements or other hardware.

The various processes described above are supposed to be realized by one microprocessor 45, but are not limited to this. These various functions include at least one processor-like semiconductor integrated circuit, at least one application-specific integrated circuit (ASIC), at least one DSP (Digital Signal Processor), and at least one FPGA (Field Programmable). It can be implemented by a Gate Array) and / or a circuit with other arithmetic functions.

These circuits can perform the various processes described above by reading one or more instructions from at least one tangible readable medium.

Such media take the form of magnetic media (eg, hard disks), optical media (eg, compact discs (CDs), DVDs), volatile memory, memory of any type of non-volatile memory, and the like. It is not limited to the form.

Volatile memory may include DRAM (Dynamic Random Access Memory) and SRAM (Static Random Access Memory). The non-volatile memory may include ROM, NVRAM.

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

40 Doppler sensor, 41 analog signal processing circuit, 43 AD converter, 45 microprocessor, 50, 50B motion detection unit, 52 output unit, 52I, 52Q amplitude detection unit, 54, 64, 74, 74B amplitude threshold confirmation unit, 55 ratio Calculation unit, 56 ratio judgment unit, 57 accuracy judgment unit, 60, 60A, 60B heart rate calculation unit, 65I, 65Q heart rate detection unit, 66, 66I, 66IA, 66IB, 66Q, 66QA, 66QB, 76I, 76IA, 76IB , 76Q, 76QA, 76QB, 86 Comparison unit, 67,77 Median processing unit, 68,78 counter, 70, 70A, 70B Respiration calculation unit, 75I, 75Q Respiration rate detection unit, 85 detection unit, 100, 100A, 100B measurement Devices, 149A, 149B, 149C, 149D signal processing circuits, 152, 152A, 152B control circuits, 154 memories, 155 history areas, 156 speakers, 158 communication interfaces, 200 terminal devices, 300 networks, 1000 measurement systems, 1500, 1600 accuracy. table.

Claims (9)

A Doppler sensor that irradiates a living body with microwaves, receives the reflected waves of the microwaves, and outputs a Doppler signal based on the microwaves and the reflected waves.
A control circuit that detects biological information including at least one of the heart rate and the respiratory rate of the living body based on the Doppler signal, and a control circuit.
It is provided with a memory for storing the detected biological information.
The control circuit
A comparison unit that compares the detected biological information with the past biological information stored in the memory.
An output unit that outputs the detected biological information when the comparison result satisfies a predetermined condition, or the biological information derived based on the biological information and the past biological information .
The comparison unit includes a counter that counts the number of times a process of comparing the detected biological information with the past biological information stored in the memory is executed.
The comparison unit is further configured to stop the comparison process when the counted number of times is a predetermined number of times.
The output unit is a measuring device configured to output the detected biological information or the derived biological information. The measuring device according to claim 1, wherein the comparison unit is configured to compare the detected biological information with the latest biological information stored in the memory. The output unit is the detected biometric information or the derived biometric information when the volatility of the detected biometric information with respect to the past biometric information stored in the memory is within a predetermined range. The measuring device according to claim 1 or 2, which is configured to output information. A Doppler sensor that irradiates a living body with microwaves, receives the reflected waves of the microwaves, and outputs a Doppler signal based on the microwaves and the reflected waves.
A control circuit that detects biological information including at least one of the heart rate and the respiratory rate of the living body based on the Doppler signal, and a control circuit.
It is provided with a memory for storing the detected biological information.
The control circuit
A comparison unit that compares the detected biological information with the past biological information stored in the memory.
An output unit that outputs the detected biological information when the comparison result satisfies a predetermined condition, or the biological information derived based on the biological information and the past biological information.
A first extraction unit that extracts a body movement signal related to the movement of the living body from the Doppler signal,
A second extraction unit that extracts a respiration signal related to the respiration of the living body from the Doppler signal,
The body and the amplitude of the motion signal, the respiration signal including a ratio calculation unit for calculating a ratio of the amplitude, total measuring device. A Doppler sensor that irradiates a living body with microwaves, receives the reflected waves of the microwaves, and outputs a Doppler signal based on the microwaves and the reflected waves.
A control circuit that detects biological information including at least one of the heart rate and the respiratory rate of the living body based on the Doppler signal, and a control circuit.
It is provided with a memory for storing the detected biological information.
The control circuit
A comparison unit that compares the detected biological information with the past biological information stored in the memory.
An output unit that outputs the detected biological information when the comparison result satisfies a predetermined condition, or the biological information derived based on the biological information and the past biological information.
A first extraction unit that extracts a body movement signal related to the movement of the living body from the Doppler signal,
A second extraction unit that extracts a respiration signal related to the respiration of the living body from the Doppler signal,
Includes a ratio calculation unit that calculates the ratio between the amplitude of the body movement signal and the amplitude of the respiration signal.
The memory further stores the correspondence between the ratio and the accuracy of the detected biological information.
And the output unit, the corresponding accuracy corresponding to the ratio based on a relationship, the detected biological information, or configured to output together with the biometric information derived, total measuring device. A Doppler sensor that irradiates a living body with microwaves, receives the reflected waves of the microwaves, and outputs a Doppler signal based on the microwaves and the reflected waves.
A control circuit that detects biological information including at least one of the heart rate and the respiratory rate of the living body based on the Doppler signal, and a control circuit.
It is provided with a memory for storing the detected biological information.
The control circuit
A comparison unit that compares the detected biological information with the past biological information stored in the memory.
An output unit that outputs the detected biological information when the comparison result satisfies a predetermined condition, or the biological information derived based on the biological information and the past biological information.
A first extraction unit that extracts a body movement signal related to the movement of the living body from the Doppler signal,
A second extraction unit that extracts a respiration signal related to the respiration of the living body from the Doppler signal,
Includes a ratio calculation unit that calculates the ratio between the amplitude of the body movement signal and the amplitude of the respiration signal.
The output unit, when the ratio the calculated satisfies the condition for a predetermined value, the detected biological information, or configured to output the biological information derived, total measuring device .. It also has a communication interface for communicating with external devices,
The invention according to any one of claims 1 to 6 , wherein the output unit is configured to output the detected biometric information or the derived biometric information to the external device via the communication interface. Measuring device. It is a measurement method for measuring biological information,
A step of irradiating a living body with a microwave, receiving a reflected wave of the microwave, and outputting a Doppler signal based on the microwave and the reflected wave.
A step of detecting biological information including at least one of the heart rate and the respiratory rate of the living body based on the Doppler signal, and
The step of storing the detected biological information in the memory and
A step of comparing the detected biological information with the past biological information stored in the memory, and
When the comparison result satisfies a predetermined condition, the detected biological information, or the step of outputting the biological information derived based on the biological information and the past biological information, and the step of outputting the biological information .
A step of counting the number of times the process of comparing the detected biological information with the past biological information stored in the memory is executed, and
A measurement method comprising a step of stopping the comparison process when the counted number of times is a predetermined number of times. A measurement program for measuring biological information
The measurement program is applied to the measuring device.
A step of irradiating a living body with a microwave, receiving a reflected wave of the microwave, and outputting a Doppler signal based on the microwave and the reflected wave.
A step of detecting biological information including at least one of the heart rate and the respiratory rate of the living body based on the Doppler signal, and
The step of storing the detected biological information in the memory and
A step of comparing the detected biological information with the past biological information stored in the memory, and
When the comparison result satisfies a predetermined condition, the detected biological information, or the step of outputting the biological information derived based on the biological information and the past biological information, and the step of outputting the biological information .
A step of counting the number of times the process of comparing the detected biological information with the past biological information stored in the memory is executed, and
A measurement program that executes a step of stopping the comparison process when the counted number of times is a predetermined number of times.

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