CN105877729A - Biological signal measuring system and method and earphone - Google Patents

Abstract

The invention discloses a biological signal measuring system and method and an earphone. The system comprises multiple light sources, multiple light sensors and a processor module. The light sources irradiate the interior of the skin surface of a testee. The light sensors receive the light sources reflected outwards from the interior of skin respectively and converting the light sources into multiple signals. The processor module receives the signals and calculates correlation coefficients between the signals so that a single PPG signal can be combined. According to the biological signal measuring system and method and the earphone, measurement in the motion process is promoted, errors caused by light noise are overcome, and the accuracy of dynamic biological signal measurement is improved.

Description

Biological signal measurement system, method and earphone

Technical field

The present invention relates to bio signal and measure field, improve biology more particularly to one The system of measuring signal accuracy, method and earphone.

Background technology

A kind of existing bio signal monitoring earphone, in order to monitor heart rate degree of variation and heart beating Rate, including an earphone, a light source and an optical sensor, earphone has the ear of a light-transmitting materials Plug, inserts earplug in auditory meatus to form dark place, then makes light source penetrate earplug, in irradiation Skin back reflection in auditory meatus, then come from the change in a period of time by optical sensor sensing light To obtain a smooth volume variable signal (Photoplethysmography, PPG), understand whereby Cardiac rate (Heart Rate).

During motion, user wears monitoring of pulse earphone to monitor the change of cardiac rate, with dimension Hold preferably exercise intensity, reach the training of more safe and effective rate whereby, as jogged, in order to Can run or maintain certain exercise intensity for a long time, it is possible to utilize monitoring of pulse ear The cardiac rate that machine provides determines running velocity.

But, during motion, health will certainly produce vibrations, now earphone in auditory meatus along with body During body vibrations, intermittent can produce gap with ear canal wall, this gap will make outside auditory meatus Light source produces light in entering auditory meatus and makes an uproar, and makes the body of light that optical sensor cannot accurately be measured in auditory meatus Long-pending change, produces error.

Bio signal measurement system the most of the present invention, method and earphone are contemplated to overcome described Defect, it is possible to overcome light to make an uproar caused error, improves the accurate of dynamic biological measuring signal Degree.

Summary of the invention

It is an object of the invention to carry for the deficiency of described existing bio signal monitoring earphone Go out the bio signal measurement system of a kind of accuracy improving dynamic biological measuring signal, method And earphone.

For reaching described purpose, the open a kind of bio signal measurement system of the present invention, if including Dry light source, respectively to testee skin surface internal radiation；Some optical sensors, receive respectively By in skin to some light sources of external reflectance and be converted into some signals；One processor module, Receive some signals the correlation coefficient that calculates between each signal to be combined into single PPG letter Number；The computing formula of described correlation coefficient is:

$R_{\mathrm{xy}}=\frac{{\mathrm{\Σ}}_i\left[(x_i-\stackrel{\‾}{x})(y_i-\stackrel{\‾}{y})\right]}{\sqrt{{\mathrm{\Σ}}_i{(x_i-\stackrel{\‾}{x})}^2}\·\sqrt{{\mathrm{\Σ}}_i{(y_i-\stackrel{\‾}{y})}^2}}$

R_xyFor the correlation coefficient that each two signal is a group, wherein x and y is respectively correspondence sensing The signal value of signal；If all coefficient R_xyTime in a feasible value, by all sensings Signal is added becomes a PPG signal, if it is not, calculate some signal x, y with following equation And coefficient R_xyTo produce each group of gained signal S_xy:

S_xy=(1-R_xy)(x+y)

Then by each group of gained signal S_xyIt is added and produces PPG signal.

As further improving, wherein laggard through fast fourier transform of PPG signal The estimation of the row rhythm of the heart and detection.

In one embodiment, wherein said some optical sensors include that the first optical sensor is used To input the first sensing signal S1, the second optical sensor in order to input the second sensing signal S2 And the 3rd optical sensor in order to input the 3rd sensing signal S3, noise canceled after, perform fortune Calculate between each signal correlation coefficient two-by-two and can obtain coefficient R₁₂、R₂₃And R₃₁, fortune After calculating correlation coefficient, set when correlation coefficient is in feasible value, calculate with following equation PPG signal:

PPG signal=S1+S2+S3

If it is not, with the following equation some signals of calculating and correlation coefficient:

PPG signal=(1-R₁₂)(S1+S2)+(1-R₂₃)(S2+S3)+(1-R₃₁)(S1+S3)

Then fast fourier transform and rhythm of the heart estimation and detection are carried out after obtaining PPG signal.

Further, bio signal measurement system includes a gravity sensor, in order to sense shock Rear generation one motor message is also sent to processor module, and processor module processes PPG signal So that amplitude is close to the amplitude of motor message, post processing PPG signal with motor message to produce PPG signal after life one is mobilisation.

Further, the wherein said processor module of bio signal measurement system senses with some light One AFE (analog front end) sensor is set between device.

Further, bio signal measurement system includes a fast flash memory and a radio communication mold Block, fast flash memory performs to store the rhythm of the heart information of processor module institute computing, radio communication Module performs the communication of processor module and other electronic equipments.

A kind of bio signal measures earphone, including an ear casing；One enters ear, is arranged at ear The side of casing；One can the earplug of printing opacity, be arranged at the free end into ear；Some light Source, is arranged at into ear, and its light is respectively at entering radially passing of ear with different angles Earplug；Some optical sensors, are arranged at into ear, if receiving some light sources respectively to produce Dry signal；One processor module, is arranged at ear casing, receives some signals and calculates each letter Correlation coefficient between number is to be combined into single PPG signal；Wherein, the phase between each signal Pass coefficient is:

$R_{\mathrm{xy}}=\frac{{\mathrm{\Σ}}_i\left[(x_i-\stackrel{\‾}{x})(y_i-\stackrel{\‾}{y})\right]}{\sqrt{{\mathrm{\Σ}}_i{(x_i-\stackrel{\‾}{x})}^2}\·\sqrt{{\mathrm{\Σ}}_i{(y_i-\stackrel{\‾}{y})}^2}}$

R_xyFor the correlation coefficient that each two signal is a group, wherein x and y is respectively correspondence sensing The signal value of signal；If all coefficient R_xyTime in a feasible value, by all sensings Signal is added becomes a PPG signal, if it is not, calculate some signal x, y with following equation And coefficient R_xyTo produce each group of gained signal S_xy:

S_xy=(1-R_xy)(x+y)

Then by each group of gained signal S_xyIt is added and produces PPG signal.

And further, described optical sensor is set to three, is evenly distributed in into ear surface On, and along entering ear's spaced radial 120 degree.

A kind of bio signal method for measurement, including:

(1) obtain some light sensing signal, and some signals are carried out respectively high-pass filtering, low Pass filter, DC filtering and vague generalization；

(2) some signals are calculated respectively to produce correlation coefficient with the compound mode of two-by-two a group, Formula is:

$R_{\mathrm{xy}}=\frac{{\mathrm{\Σ}}_i\left[(x_i-\stackrel{\‾}{x})(y_i-\stackrel{\‾}{y})\right]}{\sqrt{{\mathrm{\Σ}}_i{(x_i-\stackrel{\‾}{x})}^2}\·\sqrt{{\mathrm{\Σ}}_i{(y_i-\stackrel{\‾}{y})}^2}}$

Wherein, R_xyFor the correlation coefficient that each two signal is a group, wherein x and y is the most right Answer the signal value of sensing signal；

(3) if all coefficient R_xyTime in a feasible value, all sensing signals are added Become a PPG signal, if it is not, calculate some signal x, y and phase relation with following equation Number R_xyTo produce each group of gained signal S_xy:

S_xy=(1-R_xy)(x+y)

Then by each group of gained signal S_xyIt is added and produces a PPG signal.

In sum, compared with prior art, the bio signal measurement system of the present invention, side Method and earphone are beneficial to measure in motor process, overcome light and make an uproar caused error, improve The accuracy of dynamic biological measuring signal.

Accompanying drawing explanation

Fig. 1 is the circuit block diagram of bio signal measurement system of the present invention.

Fig. 2 is the flow chart of steps of bio signal method for measurement of the present invention.

Fig. 3 is the original sensing signal schematic diagram of the present invention.

Fig. 4 is the original sensing signal of present invention signal schematic representation after high-pass filtering.

Fig. 5 be present invention sensing signal after high-pass filtering the most low-pass filtered after signal Schematic diagram.

Fig. 6 be the present invention low-pass filtered after sensing signal signal after DC filtering again Schematic diagram.

Fig. 7 is the detailed step flow chart of bio signal method for measurement of the present invention.

Fig. 8 is the axonometric chart that bio signal of the present invention measures earphone.

Fig. 9 is the three-dimensional exploded view that bio signal of the present invention measures earphone.

In figure, each description of reference numerals is as follows.

Bio signal measurement system 1 light source 10

Optical sensor 11 processor module 12

Gravity sensor 13 AFE (analog front end) sensor 14

Fast flash memory 15 wireless communication module 16

Bio signal measures earphone 2 ear casing 21

Enter ear 22 earplug 221

Light source 23 optical sensor 24

First sensing signal S1 the second sensing signal S2

3rd sensing signal S3.

Detailed description of the invention

By describing the technology contents of the present invention, structural feature in detail, being reached purpose and effect, Hereinafter hereby illustrate and coordinate accompanying drawing to be explained in detail.

The open a kind of bio signal measurement system of the present invention, method and earphone, be according to many groups The correlation coefficient of signal, to be combined into single PPG signal, improves what bio signal measured whereby Accuracy.

Referring to Fig. 1, bio signal measurement system 1 includes that some light sources 10, some light pass Sensor 11 and a processor module 12.

Some light sources 10 are in order to irradiate to testee skin surface respectively, and irradiate respectively not Same block, makes light source penetrate after skin by organization internal to external reflectance, more respectively through some Optical sensor 11 is received the internal light source to external reflectance by the different blocks of skin and is converted into Some signals, obtain the sensing signal of skin different blocks whereby, and processor module 12 connects A rhythm of the heart value is produced after receiving some signals and processing some signals.

Refer to Fig. 2 to Fig. 6, concrete, because of detecting part between the some signals received Position is different, and the light during sensing is made an uproar impact, can produce the difference of light source reception, because of By the correlation coefficient of relatively each signal, this, will appreciate that each position light is made an uproar the difference of impact Different.

Bio signal method for measurement of the present invention is as follows: when receiving each sensing signal, it will First carrying out noise elimination, noise eliminates and includes sensing signal is carried out high-pass filtering, the most right Signal carries out low-pass filtering, then carries out DC filtering, reduces sampling frequency the most respectively (Down Sampling), then by each sensing signal vague generalization (Normalize PPG Amplitude) so that amplitude is close with energy size, the signal that amplitude energy size is close Via the judgement of correlation coefficient to be combined into a PPG signal, and the PPG letter that will be obtained Number carry out fast fourier transform, to transfer signal to frequency domain from time domain, then by PPG signal Parameter tries to achieve heart rate value through rhythm of the heart estimation with detection.

Judging of correlation coefficient is as follows with the associated methods of some signals: first, with following phase The pass coefficient formula some signals of calculating:

$R_{\mathrm{xy}}=\frac{{\mathrm{\Σ}}_i\left[(x_i-\stackrel{\‾}{x})(y_i-\stackrel{\‾}{y})\right]}{\sqrt{{\mathrm{\Σ}}_i{(x_i-\stackrel{\‾}{x})}^2}\·\sqrt{{\mathrm{\Σ}}_i{(y_i-\stackrel{\‾}{y})}^2}}$

Wherein, R_xyFor the correlation coefficient that each two signal is a group, wherein x and y is the most right Answer the signal value of sensing signal.

If all coefficient R_xyTime in a feasible value, the most all coefficient R_xy During more than or equal to feasible value, all sensing signals are added and become a PPG signal, if it is not, Some signal x, y and coefficient R are calculated with following equation_xyTo produce each group of gained signal S_xy:

S_xy=(1-R_xy)(x+y)

Then by full income signal S_xyIt is added and obtains a PPG signal, wherein, S_xyFor every two Signal after the combination of individual signal.

Referring again to Fig. 1, further, described bio signal measurement system 1 includes a gravity Sensor 13, sense shock in order to obtain a motor message and to be sent to processor module 12, And in order to perform the vague generalization (normalize) of motor message and PPG signal, it is because PPG signal differs the error that the rhythm of the heart can be caused to measure too much with the energy of motor message, Therefore in order to make energy close, perform with motor message vague generalization after can obtain mobilisation after PPG signal, make PPG signal close with the amplitude size of motor message, improve the rhythm of the heart Estimation and the accuracy detected.

Further, before a simulation being set between processor module 12 and some optical sensors 11 End sensor 14, in order to receive the sensing signal of some optical sensors 11, by detect Signal amplifies, and is converted into digital signal from analogue signal.

Further, bio signal measurement system 1 includes that a fast flash memory 15 and is wireless Communication module 16, fast flash memory 15 performs to store the rhythm of the heart of 12 computings of processor module Information, wireless communication module 16 performs the communication of processor module 12 and other electronic equipments.

As further improving, some optical sensors 11 include the first optical sensor in order to Input the first sensing signal S1, the second optical sensor in order to input the second sensing signal S2 and 3rd optical sensor in order to input the 3rd sensing signal S3, noise canceled after, perform computing Between each signal, the correlation coefficient of combination of two can obtain coefficient R₁₂、R₂₃And R₃₁, Wherein R₁₂It is the first sensing signal S1 and the correlation coefficient of the second sensing signal S2, R₂₃ It is the second sensing signal S2 and the correlation coefficient of the 3rd sensing signal S3, R₃₁It it is the 3rd sense Survey signal S3 and the correlation coefficient of the first sensing signal S1, after calculating correlation coefficient, if When settled correlation coefficient is in feasible value, the most all correlation coefficienies are all higher than or equal to 0.4 Time, calculate PPG signal with following equation, will be added and become PPG signal by some signals:

PPG signal=S1+S2+S3

If all correlation coefficienies have one non-when being more than or equal to 0.4, calculate some letters with following equation Number and correlation coefficient:

PPG signal=(1-R₁₂)(S1+S2)+(1-R₂₃)(S2+S3)+(1-R₃₁)(S1+S3)

Then fast fourier transform and rhythm of the heart estimation and detection are carried out after obtaining PPG signal.

Refer to Fig. 7, the detailed step flow chart of a kind of bio signal method for measurement, including Following steps:

(1) obtain some light sensing signal, and some signals are carried out respectively high-pass filtering, low Pass filter, DC filtering and vague generalization；

(2) some signals are calculated respectively to produce correlation coefficient with the compound mode of two-by-two a group, Formula is:

$R_{\mathrm{xy}}=\frac{{\mathrm{\Σ}}_i\left[(x_i-\stackrel{\‾}{x})(y_i-\stackrel{\‾}{y})\right]}{\sqrt{{\mathrm{\Σ}}_i{(x_i-\stackrel{\‾}{x})}^2}\·\sqrt{{\mathrm{\Σ}}_i{(y_i-\stackrel{\‾}{y})}^2}}$

Wherein, R_xyFor the correlation coefficient that each two signal is a group, wherein x and y is the most right Answer the signal value of sensing signal；

(3) if all coefficient R_xyTime in a feasible value, all sensing signals are added Become a PPG signal, if it is not, calculate some signal x, y and phase relation with following equation Number R_xyTo produce each group of gained signal S_xy:

S_xy=(1-R_xy)(x+y)

Then by each group of gained signal S_xyIt is added and produces a PPG signal.

(4) perform that PPG signal is carried out fast fourier transform and try to achieve heart rate with the estimation rhythm of the heart Value.

Referring to Fig. 8 and Fig. 9, a kind of bio signal measures earphone 2, and it includes an earphone Shell 21, one enters ear 22, some light sources 23, some optical sensors 24 and can printing opacity Earplug 221.Wherein, entering ear 22 and be arranged at the side 21 of ear casing, being configured to can To stretch into testee auditory meatus, earplug 221 is arranged at into ear 22 free end.Some light sources 23 are arranged at into ear 22, and its light passes earplug 221 with different angles respectively.Some light Sensor 24 is arranged at into ear 22, receives different skin position institute in ear 22 respectively To some light sources 23 of external reflectance to produce some signals.Processor module 12 is arranged at ear Casing 21, after receiving some signals, some signals are carried out respectively high-pass filtering, low-pass filtering, DC filtering and vague generalization to calculate the correlation coefficient between each signal single to be combined into PPG signal, finally, by after PPG signal fast fourier transform to estimate the rhythm of the heart.

The earplug 221 of described bio signal measurement earphone 2 can be chosen to the silicon of printing opacity Glue material.

And further illustrate, when bio signal measurement earphone 2 rocks, in order to be able to compare ear In road, light is made an uproar effect, and some optical sensors 24 are set to be evenly distributed in into ear On 22 surfaces, such as optical sensor 24 is set to three, and it is along entering between ear 22 radial direction Every 120 degree, when bio signal measurement earphone 2 upwards rocks, position light sensing up The most closer ear channel skin of device 24, the light of reception is made an uproar the most weak, and two groups of positions are in lower section Optical sensor 24, because away from skin, the light of reception is made an uproar stronger；Otherwise, when earphone shakes downwards Time dynamic, the light that the position optical sensor 24 in lower section receives is made an uproar the most weak, position light up The light that sensor 24 receives is made an uproar relatively strong, whereby, and the phase relation of described three optical sensors 24 Number can reflect light and make an uproar effect.

Compared with prior art, the bio signal measurement system of the present invention, method and earphone profit In measuring in motor process, overcome light and make an uproar caused error, improve dynamic biological The accuracy of measuring signal.

In sum, the present invention meets patent of invention important document, and whence proposes patent application in accordance with the law. But, the foregoing is only the preferable embodiments possible of the present invention, non-the most i.e. limit to this The scope of the claims of invention, therefore the equivalence that utilization description of the invention and accompanying drawing content are done such as Structure changes, and is the most all included within the scope of the present invention, and closes and gives Chen Ming.

Claims (10)

1. a bio signal measurement system, it is characterised in that: including: some light sources, point Not to testee skin surface internal radiation；Some optical sensors, receive respectively by skin to Some light sources of external reflectance are also converted into some signals；One processor module, receives some letters Number and calculate the correlation coefficient between each signal to be combined into single PPG signal, described relevant The computing formula of coefficient is:

$R_{\mathrm{xy}}=\frac{{\mathrm{\Σ}}_i\left[(x_i-\stackrel{\‾}{x})(y_i-\stackrel{\‾}{y})\right]}{\sqrt{{\mathrm{\Σ}}_i{(x_i-\stackrel{\‾}{x})}^2}\·\sqrt{{\mathrm{\Σ}}_i{(y_i-\stackrel{\‾}{y})}^2}}$

R_xyFor the correlation coefficient that each two signal is a group, wherein x and y is respectively correspondence sensing The signal value of signal；If all coefficient R_xyTime in a feasible value, by all sensings Signal is added becomes a PPG signal, if it is not, calculate some signal x, y with following equation And coefficient R_xyTo produce each group of gained signal S_xy:

S_xy=(1-R_xy)(x+y)

Then by each group of gained signal S_xyIt is added and produces PPG signal.

Bio signal measurement system the most according to claim 1, it is characterised in that: PPG Signal carries out rhythm of the heart estimation and detection after fast fourier transform.

Bio signal measurement system the most according to claim 1, it is characterised in that: institute State some optical sensors include the first optical sensor in order to input the first sensing signal S1, second Optical sensor is in order to input the second sensing signal S2 and the 3rd optical sensor in order to input the 3rd Sensing signal S3, noise canceled after, perform correlation coefficient energy two-by-two between each signal of computing Access coefficient R₁₂、R₂₃And R₃₁, after calculating correlation coefficient, set when relevant When coefficient is in feasible value, calculate PPG signal with following equation:

PPG signal=S1+S2+S3

If it is not, with the following equation some signals of calculating and correlation coefficient:

PPG signal=(1-R₁₂)(S1+S2)+(1-R₂₃)(S2+S3)+(1-R₃₁)(S1+S3) Then fast fourier transform and rhythm of the heart estimation and detection are carried out after obtaining PPG signal.

Bio signal measurement system the most according to claim 1, it is characterised in that: enter One step includes a gravity sensor, in order to produce a motor message after sense shock and to be sent to Processor module, processor module processes PPG signal so that amplitude shaking close to motor message Width, afterwards place's PPG signal and motor message with produce one mobilisation after PPG signal.

Bio signal measurement system the most according to claim 1, it is characterised in that: institute State and an AFE (analog front end) sensor is set between processor module and some optical sensors.

Bio signal measurement system the most according to claim 1, it is characterised in that: enter One step includes a fast flash memory and a wireless communication module, and fast flash memory performs at storage The rhythm of the heart information of reason device module institute computing, wireless communication module perform processor module and other The communication of electronic equipment.

7. a bio signal measures earphone, it is characterised in that: including: an ear casing；One Enter ear, be arranged at the side of ear casing；One can the earplug of printing opacity, be arranged at into ear Free end；Some light sources, are arranged at into ear, and its light is respectively at the radial direction entering ear On with different angles through earplug；Some optical sensors, are arranged at into ear, receive respectively Some light sources are to produce some signals；One processor module, is arranged at ear casing, if receiving Dry signal also calculates the correlation coefficient between each signal to be combined into single PPG signal；Its In, the correlation coefficient between each signal is:

$R_{\mathrm{xy}}=\frac{{\mathrm{\Σ}}_i\left[(x_i-\stackrel{\‾}{x})(y_i-\stackrel{\‾}{y})\right]}{\sqrt{{\mathrm{\Σ}}_i{(x_i-\stackrel{\‾}{x})}^2}\·\sqrt{{\mathrm{\Σ}}_i{(y_i-\stackrel{\‾}{y})}^2}}$

R_xyFor the correlation coefficient that each two signal is a group, wherein x and y is respectively correspondence sensing The signal value of signal；If all coefficient R_xyTime in a feasible value, by all sensings Signal is added becomes a PPG signal, if it is not, calculate some signal x, y with following equation And coefficient R_xyTo produce each group of gained signal S_xy:

S_xy=(1-R_xy)(x+y)

Then by each group of gained signal S_xyIt is added and produces PPG signal.

Bio signal measurement system the most according to claim 7, it is characterised in that: enter One step includes a gravity sensor, obtains a motor message in order to sense shock and is sent to place Reason device module, PPG signal at processor module is so that amplitude shaking close to motor message Width, post processing PPG signal and motor message with produce one mobilisation after PPG signal.

Bio signal measurement system the most according to claim 7, it is characterised in that: institute Stating optical sensor and be set to three, be evenly distributed on ear surface, it is along entering ear Spaced radial 120 degree.

10. a bio signal method for measurement, it is characterised in that: include,

(1) obtain some light sensing signal, and some signals are carried out respectively high-pass filtering, low Pass filter, DC filtering and vague generalization；

(2) some signals are calculated respectively to produce correlation coefficient with the compound mode of two-by-two a group, Formula is:

$R_{\mathrm{xy}}=\frac{{\mathrm{\Σ}}_i\left[(x_i-\stackrel{\‾}{x})(y_i-\stackrel{\‾}{y})\right]}{\sqrt{{\mathrm{\Σ}}_i{(x_i-\stackrel{\‾}{x})}^2}\·\sqrt{{\mathrm{\Σ}}_i{(y_i-\stackrel{\‾}{y})}^2}}$

Wherein, R_xyFor the correlation coefficient that each two signal is a group, wherein x and y is the most right Answer the signal value of sensing signal；

(3) if all coefficient R_xyTime in a feasible value, all sensing signals are added Become a PPG signal, if it is not, calculate some signal x, y and phase relation with following equation Number R_xyTo produce each group of gained signal S_xy:

S_xy=(1-R_xy)(x+y)

Then by each group of gained signal S_xyIt is added and produces a PPG signal.