A blood pressure monitoring method and device based on infrasound auscultation

Abstract

This invention relates to the field of blood pressure monitoring technology, specifically to a method and device for blood pressure monitoring based on infrasound auscultation. The method includes acquiring an auscultation signal and performing bandpass filtering on the auscultation signal to obtain a bandpass-filtered infrasound auscultation signal; performing homomorphic filtering on the bandpass-filtered infrasound auscultation signal to obtain a homomorphic envelope, determining the maximum point of the homomorphic envelope, setting a time region, and determining the maximum point, a minimum point to the left of the maximum point, and a minimum point to the right of the maximum point on the bandpass-filtered infrasound auscultation signal based on the time region; acquiring the time difference between the maximum point and the minimum point within the same time region, and calculating the diastolic blood pressure based on the time difference. This method not only allows for convenient and rapid acquisition of diastolic blood pressure, systolic blood pressure, and heart rate, but also provides high accuracy in acquiring these parameters.

Description

Technical Field

[0001] This invention relates to the field of blood pressure monitoring technology, specifically to a blood pressure monitoring method and device based on infrasound auscultation. Background Technology

[0002] Blood pressure refers to the pressure exerted by blood against the walls of blood vessels as it flows through them; it is a vital physiological indicator for maintaining life. Blood pressure is primarily composed of systolic pressure (high pressure) and diastolic pressure (low pressure). Regular blood pressure monitoring helps us detect abnormal increases or decreases in blood pressure promptly. There are two main methods for blood pressure monitoring: the first involves measuring blood pressure using a cuff, but this method is inconvenient, uncomfortable, and time-consuming. The second method uses a pressure sensor placed on a mattress to acquire a cardiac impaction signal. This signal is then processed to obtain multiple characteristic parameters, which are then input into a blood pressure prediction model to obtain the monitoring results. This method requires the subject to lie flat on the mattress where the pressure sensor is placed; any movement can reduce the accuracy of the blood pressure monitoring results or even render them ineffective. Summary of the Invention

[0003] The purpose of this invention is to provide a blood pressure monitoring method and device based on infrasound auscultation, which can not only obtain diastolic blood pressure, systolic blood pressure and heart rate easily and quickly, but also obtain diastolic blood pressure, systolic blood pressure and heart rate with high accuracy.

[0004] In a first aspect of the embodiments of the present invention, a blood pressure monitoring method based on infrasound auscultation is provided, comprising:

[0005] The auscultation signal is acquired and bandpass filtered to obtain the bandpass filtered infrasound auscultation signal;

[0006] Homomorphic filtering is applied to the bandpass-filtered infrasound auscultation signal to obtain a homomorphic envelope. The maximum point of the homomorphic envelope is determined, a time region is set, and based on the time region, the maximum point, the first minimum point to the left of the maximum point, and the second minimum point to the right of the maximum point are determined on the bandpass-filtered infrasound auscultation signal.

[0007] The time difference between the maximum and minimum points within the same time region is obtained, and the diastolic blood pressure is calculated based on the time difference. The amplitude difference between the maximum and minimum points within the same time region is obtained, and the systolic blood pressure is calculated based on the amplitude difference. The time interval between two adjacent maximum points is obtained, and the heart rate is calculated based on the time interval.

[0008] As a preferred embodiment of the present invention, bandpass filtering of the auscultation signal to obtain a bandpass filtered infrasound auscultation signal specifically includes:

[0009] The auscultation signal was bandpass filtered using a 2-12Hz forward and backward bandpass filter to obtain the bandpass filtered infrasound auscultation signal.

[0010] As a preferred embodiment of the present invention, performing homomorphic filtering on the bandpass-filtered infrasound auscultation signal to obtain a homomorphic envelope specifically includes:

[0011] The logarithm of the bandpass filtered infrasound auscultation signal is taken to obtain the logarithmic amplitude component signal;

[0012] A 4Hz Butterworth low-pass filter is used to filter the logarithmic amplitude component signal to obtain the low-pass filtered logarithmic amplitude component signal.

[0013] The logarithmic amplitude component signal after low-pass filtering is subjected to exponential operation, and the result is used as the homomorphic envelope.

[0014] As a preferred embodiment of the present invention, setting the time region specifically includes:

[0015] Determine the time point corresponding to the maximum point, subtract the first time threshold from the time point to obtain the start time point of the time region corresponding to the maximum point, and add the second time threshold to the time point to obtain the end time point of the time region corresponding to the maximum point.

[0016] As a preferred embodiment of the present invention, the diastolic blood pressure is calculated based on the time difference using the following formula:

[0017]

[0018] Where DBP is diastolic blood pressure, a is the first parameter, b is the second parameter, and T1 is the time difference.

[0019] As a preferred embodiment of the present invention, the systolic blood pressure is calculated based on the amplitude difference using the following formula:

[0020]

[0021] Where SDP is the systolic pressure, c is the third parameter, d is the fourth parameter, and F is the amplitude difference.

[0022] As a preferred embodiment of the present invention, the heart rate is calculated based on the time interval value using the following formula:

[0023]

[0024] Where HR is heart rate and T2 is the time interval.

[0025] In a second aspect of the present invention, a blood pressure monitoring device based on infrasound auscultation is provided, comprising:

[0026] The infrasound auscultation signal acquisition module is configured to acquire the auscultation signal and perform bandpass filtering on the auscultation signal to obtain the bandpass filtered infrasound auscultation signal;

[0027] The extreme point acquisition module is configured to perform homomorphic filtering on the bandpass filtered infrasound auscultation signal to obtain a homomorphic envelope, determine the maximum point of the homomorphic envelope, set a time region, and determine the maximum point, minimum point one to the left of the maximum point, and minimum point two to the right of the maximum point on the bandpass filtered infrasound auscultation signal based on the time region.

[0028] The blood pressure parameter calculation module is configured to obtain the time difference between the maximum value point and the minimum value point one within the same time area and calculate the diastolic blood pressure based on the time difference; obtain the amplitude difference between the maximum value point and the minimum value point two within the same time area and calculate the systolic blood pressure based on the amplitude difference; and obtain the time interval between two adjacent maximum values ​​and calculate the heart rate based on the time interval.

[0029] In a third aspect of the embodiments of the present invention, a computer program product is provided, including a computer program that, when executed by a processor, implements the method provided according to the first aspect.

[0030] In a fourth aspect of the present invention, an electronic device is provided, including one or more processors and a memory associated with the one or more processors, the memory being used to store program instructions that, when read and executed by the one or more processors, perform the method provided according to the first aspect.

[0031] In summary, the present invention has the following beneficial effects:

[0032] First, in this embodiment, the blood pressure monitoring method only requires placing the infrasound stethoscope over the subject's chest for at least 3 seconds while acquiring the infrasound auscultation signal, making the operation more convenient, more comfortable, and with a shorter monitoring time. Second, after obtaining the homomorphic envelope from the infrasound auscultation signal based on bandpass filtering, this blood pressure monitoring method can easily and quickly obtain the maximum point (i.e., peak point) of the homomorphic envelope. After obtaining the maximum point, it can easily and quickly obtain the corresponding time region. After obtaining the time region, it can easily and quickly determine the corresponding characteristic wave group. The J-wave (i.e., the maximum value point), I-wave (i.e., the first minimum value point), and K-wave (i.e., the second minimum value point) are identified. After determining the maximum value point, the first minimum value point, and the second minimum value point, the time difference, amplitude difference, and time interval value can be obtained easily and quickly. After obtaining the time difference, amplitude difference, and time interval value, the diastolic blood pressure, systolic blood pressure, and heart rate can be easily and quickly calculated using the corresponding formulas. That is, the blood pressure monitoring method of this embodiment can easily and quickly obtain diastolic blood pressure, systolic blood pressure, and heart rate. Finally, the diastolic blood pressure, systolic blood pressure, and heart rate obtained by the blood pressure monitoring method of this embodiment have high accuracy.

[0033] Further or more detailed beneficial effects will be described in conjunction with specific embodiments in the detailed implementation. Attached Figure Description

[0034] Figure 1 A flowchart of a blood pressure monitoring method based on infrasound auscultation according to an embodiment of the present invention is shown;

[0035] Figure 2 A block diagram of a blood pressure monitoring device based on infrasound auscultation according to an embodiment of the present invention is shown;

[0036] Figure 3 A block diagram of an electronic device according to an embodiment of the present invention is shown;

[0037] Figure 4 A schematic diagram of the infrasound auscultation signal after bandpass filtering and the homomorphic envelope of an embodiment of the present invention is shown;

[0038] Figure 5 This diagram illustrates a characteristic wavegroup and a peak of the homomorphic envelope of an infrasound auscultation signal after bandpass filtering according to an embodiment of the present invention. Detailed Implementation

[0039] Embodiments of the present invention will now be described in more detail with reference to the accompanying drawings. While some embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the invention. It should be understood that the accompanying drawings and embodiments are for illustrative purposes only and are not intended to limit the scope of protection of the invention.

[0040] In the description of embodiments of the present invention, the term "comprising" and similar terms should be understood as open-ended inclusion, i.e., "including but not limited to". The term "based on" should be understood as "at least partially based on". The term "one embodiment" or "the embodiment" should be understood as "at least one embodiment". The terms "first", "second", etc., may refer to different or the same objects. Other explicit and implicit definitions may also be included below.

[0041] Figure 1 A flowchart of a blood pressure monitoring method 100 based on infrasound auscultation according to an embodiment of the present invention is shown. The method 100 includes:

[0042] A blood pressure monitoring method based on infrasound auscultation includes:

[0043] Step 102. Acquire the auscultation signal and perform bandpass filtering on the auscultation signal to obtain the bandpass filtered infrasound auscultation signal.

[0044] In this embodiment, simply placing the infrasound stethoscope over the subject's chest for more than 3 seconds through clothing is sufficient to obtain the required infrasound auscultation signal. Compared to the method of inflating and deflating a cuff, the blood pressure monitoring method in this embodiment is more convenient to operate, more comfortable, and has a shorter monitoring time.

[0045] In this embodiment, bandpass filtering of the auscultation signal to obtain a bandpass-filtered infrasound auscultation signal specifically includes: applying a 2-12Hz forward and backward bandpass filter to the auscultation signal to obtain the bandpass-filtered infrasound auscultation signal. During the measurement process, the auscultation signal is easily affected by noise (such as motion artifacts, floor vibration, respiratory fluctuations, and electrical noise). These noises have a wide frequency range, and respiratory fluctuations and electrical noise do not exist within the frequency range of the infrasound auscultation signal. To reduce the influence of noise, this embodiment uses a 2-12Hz forward and backward bandpass filter on the auscultation signal.

[0046] The method 100 in this embodiment further includes:

[0047] Step 104. Perform homomorphic filtering on the bandpass-filtered infrasound auscultation signal to obtain a homomorphic envelope, determine the maximum point of the homomorphic envelope, set a time region, and determine the maximum point, minimum point one to the left of the maximum point, and minimum point two to the right of the maximum point on the bandpass-filtered infrasound auscultation signal based on the time region.

[0048] In this embodiment, the homomorphic filtering process performed on the bandpass-filtered infrasound auscultation signal to obtain a homomorphic envelope specifically includes:

[0049] The logarithm of the bandpass filtered infrasound auscultation signal is taken to obtain the logarithmic amplitude component signal, as shown in the following formula:

[0050]

[0051] in, This is the infrasound auscultation signal after bandpass filtering. This refers to the amplitude component of the infrasound auscultation signal after bandpass filtering. This refers to the oscillating component signal in the cardiac impulse map signal after bandpass filtering. For logarithmic amplitude component signals, It is a logarithmic oscillating component signal.

[0052] A 4Hz Butterworth low-pass filter is used to filter the logarithmic amplitude component signal to obtain the low-pass filtered logarithmic amplitude component signal. The logarithmic amplitude component signal obtained after low-pass filtering is: .

[0053] The logarithmic amplitude component signal after low-pass filtering is subjected to exponential operation, and the result is used as the homomorphic envelope. For example... Figure 4 As shown in the figure, the solid line represents the infrasound auscultation signal after bandpass filtering (i.e., SCG signal), and the dashed line represents the homomorphic envelope. Once the homomorphic envelope is determined, its maxima can be obtained, which can be understood as the peaks of the homomorphic envelope.

[0054] In this embodiment, setting the time region specifically includes:

[0055] Determine the time point corresponding to the maximum point, subtract the first time threshold from the time point to obtain the start time point of the time region corresponding to the maximum point, and add the second time threshold to the time point to obtain the end time point of the time region corresponding to the maximum point.

[0056] In this embodiment, both the first and second time thresholds can be 0.15 seconds, so the entire time range is 0.3 seconds. Combined with... Figure 5Understanding this, when the time corresponding to a certain maximum point of the homomorphic envelope is 59.9 seconds, then the start time point of the time region is 59.75 seconds, and the end time point of the time region is 60.05 seconds. This application finds that the bandpass-filtered infrasound auscultation signal includes multiple characteristic wave groups, each including an I-wave, a J-peak, and a K-wave, and the I-wave, J-peak, and K-wave of each characteristic wave group are located within a corresponding time region. That is, once a time region is determined, the corresponding I-wave, J-peak, and K-wave can be quickly found on the bandpass-filtered infrasound auscultation signal based on that time region. The J-peak is the peak closest to the maximum point of the homomorphic envelope, the I-wave is the trough point to the left of the J-peak, and the K-wave is the trough point to the right of the J-peak.

[0057] In this embodiment, based on the time region, the maximum value point is determined on the bandpass filtered infrasound auscultation signal, and the maximum value point is the J peak, the minimum value point one is the minimum value point to the left of the maximum value point, and the minimum value point two is the minimum value point to the right of the maximum value point. The minimum value point one is the I wave, and the minimum value point two is the K wave.

[0058] In step 104 of this embodiment, after obtaining the homomorphic envelope based on the infrasound auscultation signal after bandpass filtering, the maximum point (i.e., peak point) of the homomorphic envelope can be obtained easily and quickly; after obtaining the maximum point of the homomorphic envelope, the corresponding time region can be obtained easily and quickly; after obtaining the time region, the J peak (i.e., maximum point), I wave (i.e., minimum point one) and K wave (i.e., minimum point two) of the corresponding characteristic wave group can be determined easily and quickly.

[0059] The method 100 in this embodiment further includes:

[0060] Step 106. Obtain the time difference between the maximum value and the minimum value one within the same time region and calculate the diastolic blood pressure based on the time difference. Obtain the amplitude difference between the maximum value and the minimum value two within the same time region and calculate the systolic blood pressure based on the amplitude difference. Obtain the time interval between two adjacent maximum values ​​and calculate the heart rate based on the time interval.

[0061] Combined Figure 5 Once the maximum value (J wave), minimum value one (I wave), and minimum value two (K wave) are determined, the time difference can be calculated using the horizontal coordinate difference between the maximum and minimum values ​​one, the amplitude difference using the vertical coordinate difference between the maximum and minimum values ​​two, and the time interval using the horizontal coordinate difference between two adjacent maximum values. Finally, diastolic blood pressure can be directly calculated using the time difference, systolic blood pressure using the amplitude difference, and heart rate using the time interval.

[0062] In this embodiment, the diastolic blood pressure is calculated based on the time difference using the following formula:

[0063]

[0064] Where DBP is diastolic blood pressure, a is the first parameter, b is the second parameter, and T1 is the time difference.

[0065] This application discovers that diastolic blood pressure and time difference are inversely proportional. Before using this formula, a sufficient amount of data (including time difference and the corresponding true diastolic blood pressure) needs to be obtained. This data can then be used to fit an inverse proportional function, which determines the first parameter 'a' and the second parameter 'b' in the formula. In subsequent use, when obtaining the time difference, simply substituting it into the formula will directly yield the diastolic blood pressure.

[0066] In this embodiment, the systolic blood pressure is calculated based on the amplitude difference using the following formula:

[0067]

[0068] Where SDP is the systolic pressure, c is the third parameter, d is the fourth parameter, and F is the amplitude difference.

[0069] This application discovers that systolic blood pressure and amplitude difference are directly proportional. Before using this formula, a sufficient amount of data (including amplitude difference and the corresponding true systolic blood pressure) needs to be obtained. This data can then be used to fit a proportional function, which determines the third parameter c and the fourth parameter d in the formula. In subsequent use, when obtaining the amplitude difference, simply substituting it into the formula will directly yield the systolic blood pressure.

[0070] In this embodiment, the heart rate is calculated based on the time interval value using the following formula:

[0071]

[0072] Where HR is heart rate and T2 is the time interval. Once the time interval is obtained, simply substitute it into the formula above to directly calculate the heart rate.

[0073] In step 106 of this embodiment, after determining the maximum value point (i.e., J peak), the first minimum value point (i.e., I wave), and the second minimum value point (i.e., K wave), the time difference, amplitude difference, and time interval value can be obtained easily and quickly. After obtaining the time difference, amplitude difference, and time interval value, the diastolic blood pressure, systolic blood pressure, and heart rate can be calculated easily and quickly using the corresponding formulas.

[0074] Furthermore, the diastolic blood pressure obtained by the blood pressure monitoring method of this embodiment has an error of less than 3% compared to the actual diastolic blood pressure, the systolic blood pressure obtained has an error of less than 2% compared to the actual systolic blood pressure, and the heart rate obtained has an error of less than 0.2% compared to the actual heart rate. Therefore, the blood pressure monitoring method of this embodiment is not only simple and quick, but also has high accuracy in obtaining diastolic blood pressure, systolic blood pressure, and heart rate.

[0075] Figure 2 A block diagram of a blood pressure monitoring device 200 based on infrasound auscultation according to an embodiment of the present invention is shown. The device 200 includes:

[0076] The infrasound auscultation signal acquisition module 202 is configured to acquire the auscultation signal and perform bandpass filtering on the auscultation signal to obtain the bandpass filtered infrasound auscultation signal.

[0077] The extreme point acquisition module 204 is configured to perform homomorphic filtering on the bandpass filtered infrasound auscultation signal to obtain a homomorphic envelope, determine the maximum point of the homomorphic envelope, set a time region, and determine the maximum point, minimum point one to the left of the maximum point, and minimum point two to the right of the maximum point on the bandpass filtered infrasound auscultation signal based on the time region.

[0078] The blood pressure parameter calculation module 206 is configured to obtain the time difference between the maximum value point and the minimum value point one within the same time area and calculate the diastolic pressure based on the time difference; obtain the amplitude difference between the maximum value point and the minimum value point two within the same time area and calculate the systolic pressure based on the amplitude difference; and obtain the time interval between two adjacent maximum values ​​and calculate the heart rate based on the time interval.

[0079] Figure 3 A block diagram of an electronic device 300 according to some embodiments of the present invention is shown. The device 300 includes a processor 301, which performs various appropriate actions and processes based on computer program instructions loaded into random access memory (RAM) 303 according to computer program instructions stored in read-only memory (ROM) 302. Various programs and data required for the operation of the device 300 may also be stored in RAM 303. The processor 301, ROM 302, and RAM 303 are interconnected via a bus 304. An input / output (I / O) interface 305 is also connected to the bus 304.

[0080] The various processes and procedures described above, such as method 100, can be executed by processor 301. For example, in some embodiments, method 100 may be implemented as a software program tangibly contained in a machine-readable medium. In some embodiments, part or all of the software program may be loaded and / or installed on device 300 via ROM 302. When the software program is loaded into RAM 303 and executed by processor 301, one or more actions of method 100 described above may be performed.

[0081] The functions described above in this document can be performed at least in part by one or more hardware logic components. For example, exemplary types of hardware logic components that can be used, without limitation, include: field programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SoCs), payload programmable logic devices (CPLDs), and so on.

[0082] The program code used to implement the methods of the present invention can be written in any combination of one or more programming languages. This program code can be provided to a processor or controller of a general-purpose computer, special-purpose computer, or other programmable data processing device, such that when executed by the processor or controller, the program code causes the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code can be executed entirely on the machine, partially on the machine, as a standalone software package partially on the machine and partially on a remote machine, or entirely on a remote machine or server.

[0083] This invention can be a method, apparatus, system, and / or program product. The program product may include a machine-readable storage medium on which machine-readable program instructions for performing various aspects of the invention are loaded. The machine-readable program instructions described herein can be downloaded from the machine-readable storage medium to various computing / processing devices, or downloaded via a network, such as the Internet, a local area network, a wide area network, and / or a wireless network, to an external computer or external storage device. The network may include copper transmission cables, fiber optic transmissions, wireless transmissions, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the machine-readable program instructions from the network and forwards them for storage in the machine-readable storage medium of the respective computing / processing device.

[0084] Machine program instructions used to perform the operations of this invention may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, etc., and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The machine-readable program instructions may be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuitry, such as programmable logic circuitry, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), is personalized by utilizing state information from the machine-readable program instructions. This electronic circuitry can execute the machine-readable program instructions to implement various aspects of the invention.

[0085] In the context of this invention, a machine-readable medium can be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, apparatus, or device. A machine-readable medium can be a machine-readable signal medium or a machine-readable storage medium. Machine-readable media can include, but are not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing. Furthermore, although the operations are depicted in a specific order, this should be understood as requiring that such operations be performed in the specific order shown or in sequential order, or requiring that all illustrated operations be performed to achieve the desired result. In certain environments, multitasking and parallel processing may be advantageous. Similarly, while several specific implementation details are included in the above discussion, these should not be construed as limiting the scope of the invention. Certain features described in the context of individual embodiments may also be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment may also be implemented individually or in any suitable sub-combination in multiple embodiments.

[0086] Although the subject matter has been described using language specific to structural features and / or methodological logic, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or actions described above. Rather, the specific features and actions described above are merely illustrative examples of implementing the claims.

Claims

1. A blood pressure monitoring method based on infrasound auscultation, characterized in that, include: Acquire auscultation signals and perform bandpass filtering on the auscultation signals to obtain bandpass filtered infrasound auscultation signals; Homomorphic filtering is applied to the bandpass-filtered infrasound auscultation signal to obtain a homomorphic envelope. The maximum point of the homomorphic envelope is determined, a time region is set, and based on the time region, the maximum point, the minimum point one to the left of the maximum point, and the minimum point two to the right of the maximum point are determined on the bandpass-filtered infrasound auscultation signal. The time difference between the maximum and minimum points within the same time region is obtained, and the diastolic blood pressure is calculated based on the time difference. The amplitude difference between the maximum and minimum points within the same time region is obtained, and the systolic blood pressure is calculated based on the amplitude difference. The time interval between two adjacent maximum points is obtained, and the heart rate is calculated based on the time interval.

2. The method according to claim 1, characterized in that, The bandpass filtering process performed on the auscultation signal to obtain the bandpass-filtered infrasound auscultation signal specifically includes: The auscultation signal was bandpass filtered using a 2-12Hz forward and backward bandpass filter to obtain a bandpass filtered infrasound auscultation signal.

3. The method according to claim 1, characterized in that, The process of performing homomorphic filtering on the bandpass-filtered infrasound auscultation signal to obtain a homomorphic envelope specifically includes: The logarithm of the bandpass filtered infrasound auscultation signal is taken to obtain the logarithmic amplitude component signal; A 4Hz Butterworth low-pass filter is used to filter the logarithmic amplitude component signal to obtain the low-pass filtered logarithmic amplitude component signal. The logarithmic amplitude component signal after low-pass filtering is subjected to exponential operation, and the result is used as the homomorphic envelope.

4. The method according to claim 1, characterized in that, Setting the time zone specifically includes: Determine the time point corresponding to the maximum point, subtract a first time threshold from the time point to obtain the start time point of the time region corresponding to the maximum point, and add a second time threshold to the time point to obtain the end time point of the time region corresponding to the maximum point.

5. The method according to claim 1, characterized in that, The diastolic blood pressure is calculated based on the time difference using the following formula: ， Where DBP is diastolic blood pressure, a is the first parameter, b is the second parameter, and T1 is the time difference.

6. The method according to claim 1, characterized in that, The systolic blood pressure is calculated based on the amplitude difference using the following formula: ， Where SDP is the systolic pressure, c is the third parameter, d is the fourth parameter, and F is the amplitude difference.

7. The method according to claim 1, characterized in that, The heart rate is calculated based on the time interval value using the following formula: ， Where HR is heart rate and T2 is the time interval.

8. A blood pressure monitoring device based on infrasound auscultation, characterized in that, include: The infrasound auscultation signal acquisition module is configured to acquire the auscultation signal and perform bandpass filtering on the auscultation signal to obtain the bandpass filtered infrasound auscultation signal. The extreme point acquisition module is configured to perform homomorphic filtering on the bandpass filtered infrasound auscultation signal to obtain a homomorphic envelope, determine the maximum point of the homomorphic envelope, set a time region, and determine the maximum point, minimum point one to the left of the maximum point, and minimum point two to the right of the maximum point on the bandpass filtered infrasound auscultation signal based on the time region. The blood pressure parameter calculation module is configured to obtain the time difference between the maximum value point and the minimum value point one within the same time region and calculate the diastolic pressure based on the time difference; obtain the amplitude difference between the maximum value point and the minimum value point two within the same time region and calculate the systolic pressure based on the amplitude difference; and obtain the time interval between two adjacent maximum values ​​and calculate the heart rate based on the time interval.

9. A computer program product, characterized in that, Includes a computer program, which, when executed by a processor, implements the steps of the method according to any one of claims 1-7.

10. An electronic device, characterized in that, include: One or more processors, and memory associated with the one or more processors, the memory for storing program instructions that, when read and executed by the one or more processors, perform the steps of the method according to any one of claims 1-7.

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