CN105962973A - Acquiring method of fetal heart rate and fetus-voice meter - Google Patents
Acquiring method of fetal heart rate and fetus-voice meter Download PDFInfo
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- CN105962973A CN105962973A CN201610579621.9A CN201610579621A CN105962973A CN 105962973 A CN105962973 A CN 105962973A CN 201610579621 A CN201610579621 A CN 201610579621A CN 105962973 A CN105962973 A CN 105962973A
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B8/00—Diagnosis using ultrasonic, sonic or infrasonic waves
- A61B8/02—Measuring pulse or heart rate
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B8/00—Diagnosis using ultrasonic, sonic or infrasonic waves
- A61B8/48—Diagnostic techniques
- A61B8/488—Diagnostic techniques involving Doppler signals
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B8/00—Diagnosis using ultrasonic, sonic or infrasonic waves
- A61B8/52—Devices using data or image processing specially adapted for diagnosis using ultrasonic, sonic or infrasonic waves
- A61B8/5207—Devices using data or image processing specially adapted for diagnosis using ultrasonic, sonic or infrasonic waves involving processing of raw data to produce diagnostic data, e.g. for generating an image
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B8/00—Diagnosis using ultrasonic, sonic or infrasonic waves
- A61B8/08—Detecting organic movements or changes, e.g. tumours, cysts, swellings
- A61B8/0866—Detecting organic movements or changes, e.g. tumours, cysts, swellings involving foetal diagnosis; pre-natal or peri-natal diagnosis of the baby
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Abstract
The invention provides an acquiring method of the fetal heart rate and a fetus-voice meter, and relates to the field of medical instruments. The acquiring method comprises the following steps that Doppler ultrasound signals are acquired; the Doppler ultrasound signals are converted into voice frequency signals; the voice frequency signals are preprocessed to obtain voice frequency signals with the low sampling rate and the low frequency; autocorrelation calculation and product term calculation are conducted on the preprocessed voice frequency signals; the maximum value in autocorrelation calculation is taken as a first main peak value, and the second maximum value in autocorrelation calculation is taken as a second main peak value; whether the first main peak value and the second main peak value are in a diploid relation or not is judged; then the fetal heart rate is obtained according to a judging result. According to the method, the problem of fetal heart rate calculation delaying is eliminated, and the problems that the fetal heart rate is decreased by half and doubled can be well solved; in addition, the real-time requirements can be well met, and the method is more beneficial for clinical diagnosis.
Description
Technical field
The present invention relates to medical instruments field, specifically refer to acquisition methods and the fetus-voice meter of a kind of Fetal Heart Rate.
Background technology
Fetus-voice meter has important effect in clinical diagnosis, especially to perinatal monitoring, is favorably improved delivery of fetus quality, reduces fetal anomaly rate and mortality rate.The index of Fetal Heart Rate is the extremely important index of fetus, and therefore, it is extremely important that Fetal Heart Rate obtains the accuracy calculated.
The numerical procedure of fetus-voice meter Fetal Heart Rate typically uses hardware zero passage detection at present, output impulse wave, calculates two impulse wave period distances and obtains the first Fetal Heart Rate, Doppler's envelope signal is carried out auto-correlation processing, obtain second fetus heart rate, after then revising, obtain Fetal Heart Rate；Another scheme is to carry out auto-correlation processing in time domain, carries out FFT calculating at frequency domain thus obtains Fetal Heart Rate.
From the point of view of above-mentioned means, use hardware zero passage detection auxiliary to calculate Fetal Heart Rate method and yet suffer from Fetal Heart Rate and halve or double result, it addition, increase hardware cost；Use frequency FFT to assist the way amount of calculation calculating Fetal Heart Rate complicated, and Fetal Heart Rate calculates the situation having delay, it is impossible to meet the requirement of real-time well.
Summary of the invention
It is an object of the invention to solve the deficiencies in the prior art and propose the acquisition methods of a kind of Fetal Heart Rate, the problem that be there is not Fetal Heart Rate computing relay by the method, can solve Fetal Heart Rate to halve and double problem, and also it is well positioned to meet the requirement of real-time, advantageously in clinical diagnosis.
To achieve these goals, the technical scheme that the present invention takes is:
The present invention proposes the acquisition methods of a kind of Fetal Heart Rate, comprises the following steps:
Obtain Doppler ultrasound signal；
Doppler ultrasound signal is converted into audio signal；
Audio signal is carried out pretreatment, it is thus achieved that low sampling rate, the audio signal of low frequency；
Audio signal after pretreated is carried out autocorrelation calculation and product term calculating；
Taking from the maximum in correlation computations is the first main peak value, and Second Largest Value is the second main peak value；
Judge that whether the first main peak value and the second main peak value are in multiple proportion；And
According to judged result, contrast heart rate value corresponding max product item corresponding to the first main peak value and the second main peak value again, if the multiple that the first main peak value is the second main peak value, then with the max product item of heart rate value corresponding to the first main peak divided by the max product item of heart rate value corresponding to the second main peak, obtain peak value ratio, if ratio is more than predetermined threshold value, then the first main peak is required Fetal Heart Rate, and otherwise the second main peak is required Fetal Heart Rate；If the multiple that the second main peak value is the first main peak value, then with the max product item of heart rate value corresponding to the second main peak divided by the max product item of heart rate value corresponding to the first main peak, obtain peak value ratio, if ratio is more than predetermined threshold value, then the second main peak is required Fetal Heart Rate, and otherwise the first main peak is required Fetal Heart Rate.
Another aspect provides a kind of fetus-voice meter, including:
Doppler ultrasound is launched and receiver module, sends and receives Doppler ultrasound signal；
Audio conversion module, is converted into audio signal by Doppler ultrasound signal；
Sound broadcasting module, plays out audio signal；
Fetal Heart Rate computing module, obtains Fetal Heart Rate；And
Fetal Heart Rate display module, for showing acquired Fetal Heart Rate,
Wherein, described sound broadcasting module and Fetal Heart Rate computing module are connected with audio conversion module respectively.
Further, described Fetal Heart Rate computing module includes:
Down-sampled module, carries out down-sampled to audio signal；
Low-pass filtering module, carries out low-pass filtering to the signal after down-sampled；
First computing unit, carries out autocorrelation calculation and product term and calculates audio signal, and to take from the maximum in correlation computations be the first main peak value, and Second Largest Value is the second main peak value；
Judging unit, it is judged that whether the first main peak value and the second main peak value be in multiple proportion；
Second computing unit, obtains Fetal Heart Rate.
Beneficial effects of the present invention: the present invention does not increase hardware and carries out zero passage detection, assist without frequency FFT to calculate and solve the problem that Fetal Heart Rate is double and halves, the problem that the most there is not Fetal Heart Rate computing relay, halve and double problem with regard to can solve Fetal Heart Rate, and also it is well positioned to meet the requirement of real-time, advantageously in clinical diagnosis.
Accompanying drawing explanation
Fig. 1 is the flow chart of the acquisition methods of a kind of Fetal Heart Rate of the present invention；
Fig. 2 be a kind of Fetal Heart Rate of the present invention acquisition methods in flow chart in step S300；
Fig. 3 is the block diagram of fetus-voice meter of the present invention；
Fig. 4 is the block diagram of Fetal Heart Rate computing module.
Wherein, 1-doppler ultrasound is launched and receiver module, 2-audio conversion module, 3-sound broadcasting module, 4-Fetal Heart Rate computing module, 5-Fetal Heart Rate display module, the down-sampled module of 41-is fast, 42-low-pass filtering module, 43-the first computing unit, 44-judging unit, 45-the second computing unit.
Detailed description of the invention
For making the purpose of the embodiment of the present invention, technical scheme and advantage clearer, below in conjunction with the accompanying drawing in the embodiment of the present invention, technical scheme in the embodiment of the present invention is clearly and completely described, obviously, described embodiment is a part of embodiment of the present invention rather than whole embodiments.Based on the embodiment in the present invention, the every other embodiment that those of ordinary skill in the art are obtained under not making creative work premise, broadly fall into the scope of protection of the invention.
As background technology is introduced, Fetal Heart Rate in order to solve occur in current fetus-voice meter halves or the problem such as inaccurate such as double, the invention provides a kind of method obtaining Fetal Heart Rate, the problem that be there is not Fetal Heart Rate computing relay by the method, can solve Fetal Heart Rate to halve and double problem, and also it is well positioned to meet the requirement of real-time, advantageously in clinical diagnosis.
As it is shown in figure 1, be the flow chart of the acquisition methods according to one embodiment of the present invention Fetal Heart Rate, in the figure, the acquisition methods of Fetal Heart Rate includes step S100 to S700, in the step s 100, obtains Doppler ultrasound signal.To the monitoring of Fetal Heart Rate mostly according to ultrasonic Doppler technique in prior art, then in the later stage, monitoring result is processed and finally obtain Fetal Heart Rate.Subsequently, in step s 200, Doppler ultrasound signal is converted into audio signal；In step S300, audio signal is carried out pretreatment, it is thus achieved that low sampling rate, the audio signal of low frequency；In step S400, the audio signal after pretreated is carried out autocorrelation calculation and product term calculating；In step S500, taking from the maximum in correlation computations is the first main peak value, and Second Largest Value is the second main peak value；In step S600, it is judged that whether the first main peak value and the second main peak value be in multiple proportion；And in step S700, carry out a step according to judged result and carry out calculating acquisition Fetal Heart Rate.
Wherein, when the judged result in step S600 is to exist in multiple proportion between the first main peak value and the second main peak value, so being calculated as further in step S700, contrast heart rate value corresponding max product item corresponding to the first main peak value and the second main peak value, if the multiple that the first main peak value is the second main peak value, then with the max product item of heart rate value corresponding to the first main peak divided by the max product item of heart rate value corresponding to the second main peak, obtain peak value ratio, if ratio is more than predetermined threshold value, then the first main peak is required Fetal Heart Rate, otherwise the second main peak is required Fetal Heart Rate；If the multiple that the second main peak value is the first main peak value, then with the max product item of heart rate value corresponding to the second main peak divided by the max product item of heart rate value corresponding to the first main peak, obtain peak value ratio, if ratio is more than predetermined threshold value, then the second main peak is required Fetal Heart Rate, and otherwise the first main peak is required Fetal Heart Rate.
Thus, required correct Fetal Heart Rate is just obtained.
In the embodiment of the invention, as in figure 2 it is shown, above-mentioned steps S300 includes following two sub-step, i.e. S310, audio signal is carried out down-sampled, and step S320, the signal after down-sampled is carried out low-pass filtering.
As shown in Figure 3, for the block diagram according to one embodiment of the present invention fetus-voice meter, this fetus-voice meter includes that doppler ultrasound is launched and receiver module 1, audio conversion module 2, sound broadcasting module 3, Fetal Heart Rate computing module 4 and Fetal Heart Rate display module 5, wherein doppler ultrasound transmitting is sequentially connected with receiver module 1, audio conversion module 2, Fetal Heart Rate computing module 4 and Fetal Heart Rate display module 5, and sound broadcasting module 3 and Fetal Heart Rate computing module 4 are connected with audio conversion module 3 respectively.Above-mentioned doppler ultrasound is launched and receiver module 1 is used for sending and receiving Doppler ultrasound signal；Doppler ultrasound signal is converted into audio signal by audio conversion module 2；Audio signal is played out by sound broadcasting module 3；Fetal Heart Rate computing module 4 is used for obtaining Fetal Heart Rate；Fetal Heart Rate display module 5 is for showing acquired Fetal Heart Rate.
As shown in Figure 4, in a detailed description of the invention of the present invention, above-mentioned Fetal Heart Rate computing module 4 includes down-sampled module 41, low-pass filtering module the 42, first computing unit 43, judging unit 44 and the second computing unit 45 being sequentially connected with, and audio signal is carried out down-sampled by the most down-sampled module 41；Low-pass filtering module 42, carries out low-pass filtering to the signal after down-sampled；First computing unit 43, carries out autocorrelation calculation and product term and calculates audio signal, and to take from the maximum in correlation computations be the first main peak value, and Second Largest Value is the second main peak value；Judging unit 44, it is judged that whether the first main peak value and the second main peak value be in multiple proportion；Second computing unit 45, obtains Fetal Heart Rate.Will be explained in detail this fetus-voice meter is how to monitor and obtain accurate Fetal Heart Rate below.
Doppler ultrasound is launched the ultrasonic signal launched with receiver module 1 and is converted into audio signal through the conversion of audio conversion module 2, and audio signal will become the audio signal of low sampling rate, low frequency through the effect of down-sampled module 41 and low-pass filtering module 42 again.In the present embodiment, the sample rate of audio signal is 44.1KHz, if directly carrying out process below, amount of calculation is the biggest, therefore must carry out down-sampled, rate calculation scope is 50 times to 240 times per minute, and down-sampled process post-sampling rate is about 1000Hz, such as down-sampled rate is set as 25, then down-sampled post-sampling rate is 1764Hz；Low-pass filtering passband frequency range 0-256Hz.
Signal after low-pass filtering is carried out autocorrelation calculation and product term calculates, this is mainly completed by the first computing unit 43, it it is 50 to 240 times according to above-mentioned fixed rate calculation scope, so obtain the autocorrelation value that each heart rate is corresponding after autocorrelation calculation, respectively with a50, a51 ..., a240 represents；The signal after low-pass filtering is carried out simultaneously product term calculating again.Obtain the max product item of each heart rate, respectively with m50, m51 ..., m240 represents.
The result a50 to a240 that obtains auto-correlation calculates, and obtains two peak values, and to take peak-peak be the first peak value, is also main peak value, and second largest peak value is the second peak value, is also minor peaks.Heart rate that the first peak value is corresponding and heart rate corresponding to the second peak value is replaced the most respectively with ax1 with ax2.Next judging unit 44 will judge between ax1 and ax2 whether in multiple proportion.If in multiple proportion, then one of them is required Fetal Heart Rate to can be concluded that ax1 and ax2.
Subsequently, the second computing unit 45 will draw final required Fetal Heart Rate, is specially, if ax1 is the multiple of ax2, then the max product item of ax1 heart rate divided by ax2, obtain a rate value, if rate value is more than threshold value, it is determined that ax1 is required Fetal Heart Rate, and otherwise ax2 is required Fetal Heart Rate.If ax2 is the multiple of ax1, then the max product item of ax2 heart rate divided by the max product item of ax1 heart rate, obtain a rate value, if rate value is more than threshold value, it is determined that ax2 is required Fetal Heart Rate, and otherwise ax1 is required Fetal Heart Rate.
The above; being only the detailed description of the invention of the present invention, but protection scope of the present invention is not limited thereto, any those familiar with the art is in the technical scope that the invention discloses; change can be readily occurred in or replace, all should contain within protection scope of the present invention.Therefore, protection scope of the present invention should described be as the criterion with scope of the claims.
Claims (4)
1. the acquisition methods of a Fetal Heart Rate, it is characterised in that comprise the following steps:
Obtain Doppler ultrasound signal；
Doppler ultrasound signal is converted into audio signal；
Audio signal is carried out pretreatment, it is thus achieved that low sampling rate, the audio signal of low frequency；
Audio signal after pretreated is carried out autocorrelation calculation and product term calculating；
Taking from the maximum in correlation computations is the first main peak value, and Second Largest Value is the second main peak value；
Judge that whether the first main peak value and the second main peak value are in multiple proportion；And
According to judged result, contrast heart rate value corresponding max product item corresponding to the first main peak value and the second main peak value again, if the multiple that the first main peak value is the second main peak value, then with the max product item of heart rate value corresponding to the first main peak divided by the max product item of heart rate value corresponding to the second main peak, obtain peak value ratio, if ratio is more than predetermined threshold value, then the first main peak is required Fetal Heart Rate, and otherwise the second main peak is required Fetal Heart Rate；If the multiple that the second main peak value is the first main peak value, then with the max product item of heart rate value corresponding to the second main peak divided by the max product item of heart rate value corresponding to the first main peak, obtain peak value ratio, if ratio is more than predetermined threshold value, then the second main peak is required Fetal Heart Rate, and otherwise the first main peak is required Fetal Heart Rate.
The acquisition methods of a kind of Fetal Heart Rate the most according to claim 1, it is characterised in that described audio signal is carried out pretreatment, it is thus achieved that low sampling rate, the audio signal of low frequency include:
Audio signal is carried out down-sampled；
Signal after down-sampled is carried out low-pass filtering.
3. a fetus-voice meter, it is characterised in that including:
Doppler ultrasound is launched and receiver module, sends and receives Doppler ultrasound signal；
Audio conversion module, is converted into audio signal by Doppler ultrasound signal；
Sound broadcasting module, plays out audio signal；
Fetal Heart Rate computing module, obtains Fetal Heart Rate；And
Fetal Heart Rate display module, for showing acquired Fetal Heart Rate,
Wherein, described sound broadcasting module and Fetal Heart Rate computing module are connected with audio conversion module respectively.
A kind of fetus-voice meter the most according to claim 3, it is characterised in that described Fetal Heart Rate computing module includes:
Down-sampled module, carries out down-sampled to audio signal；
Low-pass filtering module, carries out low-pass filtering to the signal after down-sampled；
First computing unit, carries out autocorrelation calculation and product term and calculates audio signal, and to take from the maximum in correlation computations be the first main peak value, and Second Largest Value is the second main peak value；
Judging unit, it is judged that whether the first main peak value and the second main peak value be in multiple proportion；
Second computing unit, obtains Fetal Heart Rate.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4569356A (en) * | 1984-11-05 | 1986-02-11 | Nihon Kohden Corporation | Method and apparatus for detecting fetal heart rate by autocorrelation |
| US5170791A (en) * | 1991-03-28 | 1992-12-15 | Hewlett-Packard Company | Method and apparatus for calculating the fetal heart rate |
| CN103211624A (en) * | 2013-04-07 | 2013-07-24 | 深圳市理邦精密仪器股份有限公司 | Method and device for improving accuracy of Doppler fetal heart rate data |
| CN104274209A (en) * | 2014-08-22 | 2015-01-14 | 广东睿超电子科技有限公司 | Novel fetus-voice meter based on mobile intelligent terminal |
| CN104873222A (en) * | 2015-05-08 | 2015-09-02 | 浙江铭众生物医学创业投资有限公司 | Fetal heart rate detection method based on smart mobile terminal |
| CN204863274U (en) * | 2015-07-29 | 2015-12-16 | 深圳市安科瑞仪器有限公司 | Wireless foetus cardiotachometer |
-
2016
- 2016-07-22 CN CN201610579621.9A patent/CN105962973A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4569356A (en) * | 1984-11-05 | 1986-02-11 | Nihon Kohden Corporation | Method and apparatus for detecting fetal heart rate by autocorrelation |
| US5170791A (en) * | 1991-03-28 | 1992-12-15 | Hewlett-Packard Company | Method and apparatus for calculating the fetal heart rate |
| CN103211624A (en) * | 2013-04-07 | 2013-07-24 | 深圳市理邦精密仪器股份有限公司 | Method and device for improving accuracy of Doppler fetal heart rate data |
| CN104274209A (en) * | 2014-08-22 | 2015-01-14 | 广东睿超电子科技有限公司 | Novel fetus-voice meter based on mobile intelligent terminal |
| CN104873222A (en) * | 2015-05-08 | 2015-09-02 | 浙江铭众生物医学创业投资有限公司 | Fetal heart rate detection method based on smart mobile terminal |
| CN204863274U (en) * | 2015-07-29 | 2015-12-16 | 深圳市安科瑞仪器有限公司 | Wireless foetus cardiotachometer |
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