Specific embodiment
Various exemplary embodiments will be more fully described referring to alterations below, shown in alterationsExemplary embodiments.However, concept of the present invention may embody in many different forms, and it should not be construed as limited by institute hereinThe exemplary embodiments of elaboration.Specifically, providing these exemplary embodiments makes the present invention that will be detailed and complete, and willThe scope of concept of the present invention is sufficiently conveyed to those who familiarize themselves with the technology.In all schemas, similar number indicates similar assembly always.
[embodiment of heart rate detecting system]
Fig. 1 is please referred to, Fig. 1 is the block diagram for the heart rate detecting system being painted according to exemplifying embodiments.
Heart rate detecting system provided by the present embodiment is mainly set in wearable device, such as: smart watch, fortuneIt starts ring ... etc., but is not intended to limit wearable device must be worn in which position of user.
As shown in Figure 1, heart rate detecting system provided by the present embodiment includes at least a luminescence unit 12, optical sensor 14With processor 16, wherein processor 16 is connected to optical sensor 14 and luminescence unit 12.By and large, provided by the present embodimentHeart rate detecting system is the real-time heart rate that user is measured using light volume change graphy figure method.In simple terms, the present embodimentProvided heart rate detecting system is to emit a light using luminescence unit 12 to human body surface, is detectd followed by optical sensor 14The reflected light of the light is surveyed, and the first electric signal is generated according to the reflected light, last processor 16 just can be according to the first electricitySignal calculates the heart rate of user.In this present embodiment, luminescence unit 12 is green light LED (Light Emitted Diode), mainWant the reason is that, green light wavelength in 500 nanometers between 550 nanometers, therefore for the blood of human body, green light will not be tooIn depth penetrating body tissue, but can be absorbed by the ferroheme height in blood.
It is notably, if measuring the real-time heart rate of user using light volume change graphy figure method merely, to hold very muchIt is interfered vulnerable to extraneous factor, such as: sweat, the degree ... with skin contact.Therefore, heart rate provided by the present embodiment is detectedProcessor 16 in system according to by optical sensor 14 come the first electric signal calculate the real-time heart rate of user during,Arranged in pairs or groups to the calculation mechanism for excluding noise brought by extraneous factor, enable user the real-time rhythm of the heart more accuratelyIt is detected.
Next, the processor in heart rate detecting system provided by the present embodiment 16 will be illustrated according to by optical sensor 14And the first electric signal come calculates the calculation mechanism of the real-time heart rate of user.
It is referring to figure 2. the processor progress heart rate fortune in heart rate detecting system depicted in Fig. 1 with Fig. 3, Fig. 2 and Fig. 3The flow chart of calculation.
In simple terms, heart rate detecting system provided by the present embodiment according to by optical sensor 14 come the first electric signalThe main operational principle of heart rate for calculating user is, first by the noise remove in the first electric signal, then further according to having removedFirst electric signal of noise calculates the heart rate of user.
Must be explanatorily, because noise caused by outside environmental elements may be low frequency signal, it is also possible to high-frequency signal,For example, because human hands swing or body-sway motion caused by low frequency signal, or because human hands are quickly swung or body is fastSpeed shakes generated high-frequency signal.Therefore, as shown in Fig. 2, when processor 16 receives the first electric signal by optical sensor 14Afterwards, step S110 and step S120 can be first carried out, to remove because of low-frequency noise caused by outside environmental elements or high-frequency noise.In addition, before executing step S110 and step S120, processor 16 can be first by the first electricity in order to carry out the operation of noise removeSignal switchs to frequency-region signal by time-domain signal, and those skilled in the art will be understood that how to the first electric signal carry out time domain withConversion between frequency domain is not just repeated in this.
The removal of processor 16 is first through a low-frequency noise meter because of the mode of low-frequency noise caused by outside environmental elementsIt calculates formula and calculates low-frequency noise, then again by the calculated low-frequency noise of institute by being deducted in the first electric signal.In the present embodimentIn, low-frequency noise calculation formula is as follows:
Wherein Y [i] is low-frequency noise, and X [i+j] is the first electric signal, and M is sampling sample number.
Similarly, processor 16 is removed because the mode of high-frequency noise caused by outside environmental elements is first through a high frequencyNoise calculation formula calculates high-frequency noise, then again by the calculated high-frequency noise of institute by deducting in the first electric signal.Yu BenIn embodiment, high-frequency noise calculation formula is as follows:
Wherein S [i] is high-frequency noise, and Z [i+j] is the first electric signal for deducting low-frequency noise, and M is sampling sample number.
After processor 16 deducts the low-frequency noise in the first electric signal with high-frequency noise, step will be then executedS130, to carry out peak sensing to the first electric signal.The purpose for carrying out peak sensing to the first electric signal is to be to find out human bodyThe time point that heart is beaten each time.In simple terms, it is calculated multiple to carry out peak sensing institute to the first electric signal for processor 16After several peak values, as time point for beating each time of human heart at the time of each peak value occurs.Must be explanatorily, processor16 before carrying out peak sensing to the first electric signal, the first electric signal first can be gone back to time-domain signal by frequency-region signal, and originallyHow field technical staff will be understood that the conversion between the first electric signal progress time-domain and frequency-domain, just not repeat in this.
As shown in figure 3, in this present embodiment, step S130 can be described further with step S132~step 138.LocatingDevice 16 is managed during carrying out peak sensing, first voltage value corresponding to each unit time in the first electric signal can be carried outJudgement, i.e. execution step S132.It must be explanatorily that the unit time described herein is the inverse of the first sampling rate.FurtherlyBright, processor 16 is to be cut the first electric signal with this unit time, and then each unit time will correspond to the first electricityOne voltage value of signal, then processor 16 again sentences voltage value corresponding to each unit time in the first electric signalIt is disconnected.
Processor 16 is that voltage corresponding to which is judged in the first electric signal by step S134 is executed unit timeValue is peak value.It further illustrates, in step S134, processor 16 was judged in the first electric signal corresponding to a unit timeWhether voltage value is greater than all voltage values corresponding to first three unit time, also greater than institute corresponding to secondary three unit timeThere is voltage value, and the voltage value is also greater than the average value of all voltage values corresponding to all unit time.If processor 16Judge that voltage value corresponding to a unit time is greater than all voltage values corresponding to first three unit time in the first electric signal,Also greater than all voltage values corresponding to secondary three unit time, and the voltage value was also greater than corresponding to all unit timeThe average value of all voltage values, then processor 16 will judge the voltage value for one of peak value of the first electric signal.
However, if processor 16 judges that voltage value corresponding to a unit time is single no more than first three in the first electric signalAll voltage values or no more than all voltage values or the voltage value corresponding to secondary three unit time corresponding to the time of positionNo more than the average value of all voltage values corresponding to all unit time, then processor 16 will judge that the voltage value is notOne of the peak value of first electric signal.In in this case, processor 16 will be then to voltage corresponding to next unit timeValue is judged.
In addition, processor 16 can also then execute step S136 after executing step S134, to judge that the voltage value isNo is voltage value corresponding to the last one unit time in the first electric signal.If the voltage value be not in the first electric signal mostVoltage value corresponding to the latter unit time, then processor 16 will continue then to electricity corresponding to next unit timePressure value is judged.However, if the voltage value is voltage value corresponding to the last one unit time in the first electric signal,Processor 16 will terminate this peak sensing process.
Finally, after processor 16 carries out peak sensing to the first electric signal and calculates a plurality of peak values, processor 16Step S140 can be executed, with using institute calculated first electric signal a plurality of peak values calculating user heart rate.Multiple such as Fig. 3Shown, in this present embodiment, step S140 can be described further with step S142 with step 144.It further illustrates, processor16 first carry out step S142, the time interval between a plurality of peak values to calculate the first electric signal.Processor 16 calculatesThe practice of time interval between a plurality of peak values of first electric signal is mainly by the difference of two peak value adjacent in the first electric signalDivided by the first sampling rate.Then, processor 16 execute step S144, by calculated time interval be converted into user'sHeart rate.Processor 16 be mainly through one first heart rate conversion formula by calculated time interval be converted into the heart of userRate, and this first heart rate conversion formula is as follows:
Wherein, BPM is the heart rate, and T is the difference of adjacent two peak value in the first electric signal, and n is peak in the first electric signalThe quantity of value.
According to the above description, heart rate detecting system provided by the present embodiment can be for because caused by outside environmental elementsLow-frequency noise or high-frequency noise correct the first electric signal caused by optical sensor.Through corrected first telecommunicationsNumber, the heart rate of user just can be accurately calculated in heart rate detecting system provided by the present embodiment.
[another embodiment of heart rate detecting system]
Referring to figure 4., Fig. 4 is the block diagram for the heart rate detecting system being painted according to another exemplary embodiments of the present invention.
Heart rate detecting system provided by the present embodiment is mainly set in wearable device, such as: smart watch, fortuneIt starts ring ... etc., but is not intended to limit wearable device must be worn in which position of user.
Although heart rate detecting system provided by previous embodiment has been directed to because of low frequency caused by outside environmental elementsNoise or high-frequency noise correct the first electric signal caused by optical sensor, but it is mainly with regard to the first electric signal sheetBody goes to make operation to calculate the low-frequency noise that must be deducted or high-frequency noise.In order to effectively judge noise, in addition to precedingIt states outside the component in heart rate detecting system provided by embodiment, heart rate detecting system provided by the present embodiment is more provided with dynamicMake sensor.Due to being provided with an action sensor, heart rate detecting system provided by the present embodiment can utilize movement moreThe action message of sensor human user obtained is as contrasting data, to judge noise from the first electric signal and detainIt removes.It goes to make what operation was deducted to calculate palpus with regard to first electric signal itself compared with heart rate detecting system provided by previous embodimentThe practice of low-frequency noise or high-frequency noise, heart rate detecting system provided by the present embodiment can more accurately measure the heart of userRate.
As shown in figure 4, heart rate detecting system provided by the present embodiment includes at least a luminescence unit 12, optical sensor14, action sensor 15 and processor 16, wherein processor 16 is connected to optical sensor 14, action sensor 15 and luminescence unit12。
By and large, heart rate detecting system provided by the present embodiment is measured also with light volume change graphy figure methodThe real-time heart rate of user.In this present embodiment, luminescence unit 12 emits a light to human body surface, followed by optical sensorThe reflected light of the 14 detecting light, and the first electric signal is generated according to the reflected light；On the other hand, 15 meeting of action sensorThe action message of human body is captured, and the second electric signal is generated according to the action message captured.The heart provided by the present embodimentProcessor 16 in rate detecting system is that basis is produced by the first electric signal that optical sensor 14 generates with by action sensor 15The second raw electric signal calculates the heart rate of user.
Heart rate detecting system is compared to heart rate detecting system provided by previous embodiment as provided by the present embodimentIt is provided with an action sensor 15, therefore the processor 16 in heart rate detecting system provided by the present embodiment is calculated and used moreProcessor 16 in heart rate detecting system provided by the calculation mechanism and previous embodiment of the real-time heart rate of person calculates userReal-time heart rate calculation mechanism it is not identical.
Referring to figure 5. with Fig. 6-1 and Fig. 6-2, Fig. 5, Fig. 6-1 and Fig. 6-2 are in heart rate detecting system depicted in Fig. 4The flow chart of processor progress heart rate operation.
It has been observed that in this present embodiment, processor 16 can according to the first electric signal generated by optical sensor 14 with by movingMake the second electric signal of the generation of sensor 15 to calculate the heart rate of user.For convenience to the first electric signal and the second electric signal intoRow operation, as shown in figure 5, processor 16 can first carry out step S210, with regular first electric signal and the second electric signal, so thatThe first electric signal and the second electric signal amplitude having the same after normalization.Must be explanatorily, execute step S210 itBefore, the first electric signal and the second electric signal first can be switched to frequency-region signal by time-domain signal by processor 16, and those skilled in the artHow member will be understood that the conversion between the first electric signal and the second electric signal progress time-domain and frequency-domain, just not repeat in this.
It further illustrates, as shown in Fig. 6-1 and Fig. 6-2, in this present embodiment, step S210 can be further with step S212~step 218 describes.In step S212, processor 16 can be first to respectively taking the first electric signal and the second electric signalSample, and the sampling rate system that processor 16 is respectively sampled the first electric signal and the second electric signal is defined as the second sampling rate.Processor 16 will obtain the plurality of sample of the first electric signal after being sampled respectively to the first electric signal and the second electric signalThe plurality of sample numerical value of numerical value and the second electric signal.Then in step S214~step S216, processor 16 can calculate instituteState the flat of the average value of the multiple sample values of the first electric signal and the multiple sample values of second electric signalMean value, and the standard deviation of the multiple sample values of the first electric signal and the multiple sample of the second electric signal can be calculatedThe standard deviation of this numerical value.Finally, processor 16 can be according to the average value and standard deviation of the first electric signal in step S218And second electric signal average value and standard deviation, calculate the amplitude of the first electric signal and the second electric signal, it is then just completeAt the normalization of the first electric signal and the second electric signal.
Next, in step S220, processor 16 can be expanded using an extrapolation in order to make data volume carry out operation enoughThe frequency range of the big frequency range for calculating the first electric signal and the second electric signal.In this present embodiment, processor 16 is with anti-It penetrates extrapolation (Extrapolation by Reflection) and expands the frequency range and the second electric signal for calculating the first electric signalFrequency range, and those skilled in the art will be understood that reflection extrapolation Computing Principle, just do not repeated in this.In addition, placeIt manages after device 16 expands and calculate the frequency range of the first electric signal and the frequency range of the second electric signal, it can be by the first electric signal and theTwo electric signals are filtered, with the subsequent signal processing of benefit.
In step S230, processor 16 can respectively be sampled the first electric signal through filtering with the second electric signal,To obtain the first discrete value list and the second discrete value list.It must be explanatorily that the first discrete value list and the second discrete value arrangeTable respectively includes a plurality of discrete values, and the discrete value in the first discrete value list is 16 pairs of processor the first telecommunications through filteringObtained signal data after number being sampled, similarly, the discrete value in the second discrete value list are 16 pairs of processor warpsObtained signal data after second electric signal of filtering is sampled.In this present embodiment, processor 16 is to utilize discrete FuVertical leaf transformation (Discrete Fourier Transform；DFT) come to through filtering the first electric signal and the second electric signal intoRow operation is to obtain the first discrete value list and the second discrete value list.
It has been observed that heart rate detecting system provided by the present embodiment utilizes action sensor human user obtainedAction message (that is, second electric signal) is as contrasting data, to judge noise from the first electric signal and deduct.Therefore,In step S240, processor 16 can be according in the multiple discrete value and the second discrete value list in the first discrete value tableThe multiple discrete value calculates a leading value, and wherein this leading value is the heart rate for being relevant to user.
Processor 16 be will be described below how according to the multiple discrete value and the second discrete value in the first discrete value tableThe multiple discrete value in list calculates the heart rate of user.As shown in Fig. 6-1 and Fig. 6-2, in this present embodiment, stepS240 can be described further with step S242~step 248.By and large, processor 16 is mainly by the first discrete value listIn the multiple discrete value contrasted with the multiple discrete value in the second discrete value list, to deduct noise and judgeIt is relevant to the leading value of the heart rate of user.
In step S242, processor 16 can first judge that the maximum value of multiple discrete values described in the first discrete value list isThe no maximum value for being less than or equal to multiple discrete values described in the second discrete value list.If described in the first discrete value list it is multiple fromThe maximum value for dissipating value is greater than the maximum value of multiple discrete values described in the second discrete value list, then processor 16 executes stepThe maximum value of multiple discrete values described in first discrete value list is judged as leading value by S243.On the other hand, if first is discreteThe maximum value of multiple discrete values described in value list is less than or equal to the maximum value of multiple discrete values described in the second discrete value list,Indicating the noise in the first electric signal enough influences the signal for being actually relevant to the heart rate of user, and then processor 16 will executeStep S244, to leave out the maximum value of multiple discrete values described in the first discrete value list.
However, the degree of the signal in order to more accurately judge the practical heart rate for being relevant to user of influence of noise, processor16 can further execute step S246, in terms of before the discrete value and heart rate detecting system for judging to be left out in step S244 onceWhether the difference of the heart rate of calculating is less than a threshold value.In this present embodiment, this threshold value is set as 12.If the discrete value left outIt is more than or equal to 12 with the difference of calculated heart rate primary before heart rate detecting system, then it represents that is left out in step S244 is discreteValue is noise, and then processor 16 executes step S247, and the second largest value of multiple discrete values described in the first discrete value list is sentencedBreak to dominate value.On the other hand, if the discrete value left out and the difference of calculated heart rate primary before heart rate detecting system are less than12, then it represents that the discrete value left out in step S244 has influence of the part by noise, and then processor 16 executes stepS248, based on the average value judgement of the second largest value of multiple discrete values described in the discrete value left out and the first discrete value listLead value.
After processor 16 executes the step S242~step 248, i.e., expression processor is according to the second electric signal by theNoise in one electric signal deducts, and judges the leading value for the frequency domain for being actually relevant to the heart rate of user.Then, processor16 will then execute step S250, to calculate the heart rate of user according to the leading value judged.In this present embodiment,Processor 16 is that the leading value judged is converted to the heart rate used measured through the second heart rate conversion formula.In this present embodiment, the second heart rate conversion formula is as follows:
BPM=fselect8d*60
Wherein, fselectedFor the leading value (frequency selected in dft) of the aforementioned frequency domain judged.
According to the above description, action sensor human body obtained is utilized in heart rate detecting system provided by the present embodimentThe action message of user is as contrasting data, to judge noise from the first electric signal and deduct.In this way, just can be byThe noise contribution generated by user's body movement is excluded in first electric signal, and then more accurately calculates the heart of userRate.
[embodiment of wearable device]
Wearable device system provided by the present embodiment is provided with any heart rate detecting system provided by previous embodimentSystem, to achieve the purpose that accurately to measure the heart rate of user.Such as: for example, wearable dress provided by the present embodimentSet can for smart watch, motion bracelet ... etc., but the present invention in this be not intended to limit wearable device must wear in user whichA position.In addition, the Yu Qianshu of the correlative detail of heart rate detecting system set by wearable device provided by the present embodimentIt is described in detail in embodiment, is not just repeated in this.
[possibility effect of embodiment]
In conclusion heart rate detecting system provided by the present invention can be for because of extraneous ring with the wearable device using itLow-frequency noise caused by the factor of border or high-frequency noise correct electric signal caused by optical sensor.Through correctedElectric signal, heart rate detecting system provided by the present invention with using its wearable device just can be accurately calculated user'sHeart rate.
In addition to this, heart rate detecting system provided by the present invention is more utilized movement with the wearable device using it and passesThe action message of sensor human user obtained is as contrasting data, to judge to make an uproar from the electric signal that optical sensor generatesIt sound and deducts.In this way, exclude the making an uproar for generating due to user's body movement in the electric signal that just can be generated by optical sensorSound ingredient, and then more accurately calculate the heart rate of user.
Must be explanatorily finally, in preceding description, although by the concept of the technology of the present invention with multiple exemplary implementationsExample is specifically illustrated in and illustrates, however has usually intellectual in the field of technique and will be understood that, without departing substantially from by followingUnder conditions of the range of the concept of the technology of the present invention that claim is defined, it can be made each in form and detailsKind variation.