Walking state vital sign monitoring method, device and equipment and storage medium

Abstract

The application discloses a walking state vital sign monitoring method and device, equipment and a storage medium, and relates to the technical field of vital sign monitoring. The specific scheme comprises the following steps: determining an anchor distance gate according to the first K frames in N frames of FMCW radar echo signals; performing a processing step on each frame of FMCW radar echo signal after the Kth frame to obtain a plurality of third signals, a plurality of target distance gates, and then determining a plurality of second signals, and then determining a respiratory frequency and a heartbeat frequency and sending the respiratory frequency and the heartbeat frequency to an upper computer to monitor the vital signs of a human body. The processing step comprises the following steps: updating the anchor distance gate according to the target distance gate corresponding to the last frame of the current frame of FMCW radar echo signal; determining the target distance gate according to the plurality of first signals and the anchor distance gate; and determining the third signal according to the plurality of first signals and the target distance gate. The present application can solve the problem that it is difficult to accurately monitor the vital signs of a human body in a walking state, expand the application scenarios of vital sign monitoring, and improve the accuracy of vital sign monitoring.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vital sign monitoring, and particularly relates to a walking state vital sign monitoring method and device, equipment and a storage medium. BACKGROUND

[0002] In the field of human vital sign monitoring, heartbeat and respiration are key indicators for evaluating the health condition of a human body. With the help of FMCW (Frequency-Modulated Continuous Wave) technology, non-contact monitoring of heartbeat and respiration can be achieved.

[0003] At present, a frequency-modulated continuous wave signal is emitted to a human body by a FMCW radar, a reflected echo signal is received, and the received echo signal is processed to capture the heartbeat frequency sign and the respiration frequency sign of the human body, thereby achieving monitoring of the heartbeat and respiration of the human body.

[0004] However, the existing method has poor accuracy in monitoring vital signs in a walking state of a human body. SUMMARY

[0005] Embodiments of the present application provide a walking state vital sign monitoring method, device, equipment and storage medium, solve the problem that the existing technology can only be applied to limited scenarios and cannot accurately monitor the vital signs of a human body in a walking state, expand the applicable scenarios of vital sign monitoring, and improve the accuracy of vital sign monitoring.

[0006] In a first aspect, embodiments of the present application provide a walking state vital sign monitoring method, comprising:

[0007] N frames of FMCW radar echo signals are received, wherein each frame of the FMCW radar echo signals comprises a plurality of first signals, N is a positive integer; an anchor range gate is determined according to K frames of the N frames of FMCW radar echo signals, K is a positive integer and less than N; for each frame of the FMCW radar echo signals after the Kth frame of the N frames of FMCW radar echo signals, a processing step is performed respectively to obtain a plurality of third signals and a plurality of target range gates, the plurality of third signals and the plurality of target range gates correspond one by one; a plurality of second signals are determined according to the plurality of third signals and the plurality of target range gates, wherein the second signal is a third signal eliminating human walking interference; a breathing frequency and a heartbeat frequency are determined according to the plurality of second signals; the breathing frequency and the heartbeat frequency are sent to an upper computer to monitor the vital signs of the human body; wherein the processing step comprises: updating the anchor range gate according to a target range gate corresponding to a last frame of FMCW radar echo signals of a current frame of FMCW radar echo signals; determining a target range gate in which the human body is located according to the plurality of first signals and the anchor range gate; determining a third signal according to the plurality of first signals and the target range gate, the third signal being an average signal of the first signals located in the target range gate.

[0008] Further, the anchor range gate is determined according to K frames of the N frames of FMCW radar echo signals, comprising:

[0009] The plurality of first signals respectively corresponding to the K frames of FMCW radar echo signals are respectively subjected to fast Fourier transform along a distance dimension and then subjected to fast Fourier transform along a slow time dimension to obtain a plurality of first Doppler-range spectra; the plurality of first Doppler-range spectra are superimposed to obtain a second Doppler-range spectrum; and the anchor range gate is determined according to the second Doppler-range spectrum.

[0010] Further, the target range gate in which the human body is located is determined according to the plurality of first signals and the anchor range gate, comprising:

[0011] The plurality of first signals are subjected to fast Fourier transform along a distance dimension and then subjected to fast Fourier transform along a slow time dimension to obtain a plurality of third Doppler-range spectra; and the target range gate is determined according to the plurality of third Doppler-range spectra and the anchor range gate.

[0012] Further, the target range gate is determined according to the plurality of third Doppler-range spectra and the anchor range gate, comprising:

[0013] A target motion speed of human walking is determined according to the plurality of third Doppler-range spectra; a range gate range is determined according to the anchor range gate and the target motion speed; and the target range gate is determined according to the range gate range and the plurality of third Doppler-range spectra.

[0014] Further, the third signal is determined according to the plurality of first signals and the target range gate, comprising:

[0015] performing fast Fourier transform on the plurality of first signal ranges in the distance dimension, adding and averaging the first signal ranges located in the target distance gates in the slow time dimension to obtain a third signal; and determining a phase value of the third signal by using arctangent demodulation according to the third signal.

[0016] Further, the plurality of second signals are determined according to the plurality of third signals and the plurality of target distance gates, including:

[0017] performing unwrapping operation on the phase values of the plurality of third signals to obtain a plurality of first phases; determining a plurality of second phases according to the plurality of first phases and the plurality of target distance gates; and determining the plurality of second signals according to the plurality of second phases and the plurality of third signals.

[0018] Further, the respiratory frequency and the heartbeat frequency are determined according to the plurality of second signals, including:

[0019] a first-order phase difference signal is determined according to the plurality of second signals; and the respiratory frequency and the heartbeat frequency are determined according to the first-order phase difference signal.

[0020] Further, the respiratory frequency and the heartbeat frequency are determined according to the first-order phase difference signal, including:

[0021] the respiratory frequency is determined by performing fast Fourier transform on the first-order phase difference signal; and the heartbeat frequency is determined by using a target algorithm according to the first-order phase difference signal; wherein the target algorithm is an improved adaptive noise complete ensemble empirical mode decomposition algorithm.

[0022] In a second aspect, an embodiment of the present application provides a walking state vital sign monitoring device, including:

[0023] a receiving module configured to receive N frames of FMCW radar echo signals, wherein each frame of the FMCW radar echo signals includes a plurality of first signals, and N is a positive integer.

[0024] a first processing module configured to determine an anchor distance gate according to K frames of the N frames of FMCW radar echo signals, and K is a positive integer less than N.

[0025] a second processing module configured to perform a processing step on each frame of FMCW radar echo signals after the Kth frame of the N frames of FMCW radar echo signals to obtain a plurality of third signals and a plurality of target distance gates, and the plurality of third signals and the plurality of target distance gates correspond to each other.

[0026] a determining module configured to determine a plurality of second signals according to the plurality of third signals and the plurality of target distance gates, wherein the second signals are the third signals with human walking interference eliminated.

[0027] The monitoring module is configured to determine the respiratory frequency and the heartbeat frequency according to the plurality of second signals, and transmit the respiratory frequency and the heartbeat frequency to the host computer to monitor the vital signs of the human body.

[0028] The processing step comprises: updating an anchor range gate according to a target range gate corresponding to a previous frame of the FMCW radar echo signal of the current frame; determining a target range gate where the human body is located according to the plurality of first signals and the anchor range gate; and determining a third signal according to the plurality of first signals and the target range gate, the third signal being an average signal of the first signals located in the target range gate.

[0029] In a third aspect, an apparatus is provided, and the apparatus includes: a processor; a memory for storing processor-executable instructions; and the processor implements the method in the first aspect or any possible implementation of the first aspect when executing the processor-executable instructions.

[0030] In a fourth aspect, a non-transitory computer-readable storage medium is provided, and the non-transitory computer-readable storage medium includes a computer program or instructions stored thereon, which, when executed, cause the method in the first aspect or any possible implementation of the first aspect to be implemented.

[0031] The one or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:

[0032] In the embodiments of the present application, the anchor range gate is determined according to the first K frames of the N frames of FMCW radar echo signals, and the processing step is performed on each frame of FMCW radar echo signal after the Kth frame of the N frames of FMCW radar echo signals to obtain a plurality of third signals and a plurality of target range gates. The plurality of second signals are determined according to the plurality of third signals and the plurality of target range gates, and the second signal is the third signal after the target motion phase is eliminated. According to the plurality of second signals, the respiratory frequency and the heartbeat frequency are determined, the respiratory frequency and the heartbeat frequency can be quickly and accurately determined through the second signal in which the human walking interference is eliminated, the vital signs of the human body are monitored, the problem that the existing technology can be applied to limited scenarios and it is difficult to accurately monitor the vital signs of the human body in the walking state is solved, the application scenarios of vital sign monitoring are expanded, and the accuracy of vital sign monitoring is improved. BRIEF DESCRIPTION OF DRAWINGS

[0033] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments of the present application or the prior art description. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0034] Figure 1 A flowchart of a walking state vital sign monitoring method provided for an embodiment of the present application is shown in the figure.

[0035] Figure 2 A composition diagram of a walking state vital sign monitoring device provided for an embodiment of the present application is shown in the figure. DETAILED DESCRIPTION

[0036] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work belong to the scope of protection of the present application.

[0037] The following describes some technologies related to the embodiments of the present application to help understanding, which should be considered only as exemplary. Therefore, those of ordinary skill in the art should recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present application. Also, for clarity and conciseness, the description of some well-known functions and structures is omitted in the following description.

[0038] In the field of human vital sign monitoring, heartbeat and respiration are key indicators for assessing the health status of the human body. With the help of FMCW (Frequency-Modulated Continuous Wave) technology, non-contact monitoring of heartbeat and respiration can be achieved.

[0039] Currently, a frequency-modulated continuous wave signal is emitted to the human body by a FMCW radar, the reflected echo signal is received, and certain signal processing is performed on the received echo signal, so as to capture the heartbeat frequency sign and the respiration frequency sign of the human body, thereby achieving monitoring of the heartbeat and respiration of the human body.

[0040] However, the existing method has poor accuracy in monitoring vital signs during human walking.

[0041] Under this background, the present disclosure provides a walking state vital sign monitoring method, which can solve the problem that the existing technology can only be applied to limited scenarios and is difficult to accurately monitor the vital signs of the human body in a walking state, expand the applicable scenarios of vital sign monitoring, and improve the accuracy of vital sign monitoring.

[0042] The execution subject of the walking state vital sign monitoring method provided in the embodiments of the present disclosure can be a computer or a server, or can also be other electronic devices with data processing capability; or the execution subject of the method can also be a processor (for example, a central processing unit (CPU)) in the above-mentioned electronic devices; or the execution subject of the method can also be an application (APP) installed in the above-mentioned electronic devices and capable of realizing the function of the method; or the execution subject of the method can also be a functional module or unit with the function of the method in the above-mentioned electronic devices, and the like. The execution subject of the method is not limited herein.

[0043] The walking state vital sign monitoring method will be exemplarily described below with reference to the accompanying drawings.

[0044] Figure 1 is a flowchart of the walking state vital sign monitoring method provided in the embodiments of the present disclosure. Wherein, Figure 1 Only one execution order is shown in the embodiments of the present disclosure, and it does not represent the only execution order of the walking state vital sign monitoring method, and as long as the final result can be achieved, Figure 1 The steps shown can be executed in parallel or in reverse. For example, Figure 1 The method can include:

[0045] S101, receiving N frames of FMCW radar echo signals.

[0046] Each frame of FMCW radar echo signal includes a plurality of first signals, and N is a positive integer.

[0047] For example, N can be 10 or 20, which is not limited.

[0048] For example, the first signal can be a chirp signal. Generally, the number of first signals included in each frame of FMCW radar echo signal is the same.

[0049] It can be understood that the FMCW radar transmits a plurality of frames of radar signals each including a plurality of chirp signals.

[0050] S102, determining an anchor distance gate according to the first K frames of FMCW radar echo signals in the N frames of FMCW radar echo signals.

[0051] Wherein, K is a positive integer and less than N.

[0052] For example, the anchor distance gate can be used to indicate the distance gate where the human body is located in the first K frames of FMCW radar echo signals.

[0053] Specifically, the anchor distance gate is determined according to K frames of FMCW radar echo signals in N frames of FMCW radar echo signals, comprising:

[0054] The first Doppler-range spectrum of each of the K frames of FMCW radar echo signals is obtained by performing fast Fourier transform on the first signals corresponding to the K frames of FMCW radar echo signals respectively along the distance dimension and then along the slow time dimension; the second Doppler-range spectrum is obtained by superimposing the first Doppler-range spectrum; and the anchor distance gate is determined according to the second Doppler-range spectrum.

[0055] For example, the value of K is not limited, and generally ranges from 5 to 10.

[0056] For example, the first Doppler-range spectrum of the first frame of FPCW radar echo signals can be obtained by performing fast Fourier transform on the p first signals corresponding to the first frame of FPCW radar echo signals along the distance dimension and then along the slow time dimension; the first Doppler-range spectrum of the second frame of FPCW radar echo signals, the first Doppler-range spectrum of the third frame of FPCW radar echo signals, and the first Doppler-range spectrum of the Kth frame of FPCW radar echo signals can be obtained by performing the same processing on the p first signals corresponding to the second frame of FPCW radar echo signals, the p first signals corresponding to the third frame of FPCW radar echo signals, and the p first signals corresponding to the Kth frame of FPCW radar echo signals, respectively; and the second Doppler-range spectrum can be obtained by superimposing the K×p first Doppler-range spectra.

[0057] For example, the value of p can be 32, which is not limited.

[0058] For example, after obtaining the second Doppler-range spectrum, the peak value of the second Doppler-range spectrum can be found, and the distance gate corresponding to the peak value is determined as the anchor distance gate.

[0059] In this way, the anchor distance gate can be accurately determined according to the K frames of FMCW radar echo signals.

[0060] S103, for each frame of FMCW radar echo signal after the Kth frame of FMCW radar echo signal in the N frames of FMCW radar echo signal, a processing step is performed to obtain a plurality of third signals and a plurality of target distance gates.

[0061] The plurality of third signals and the plurality of target distance gates correspond to each other.

[0062] It can be understood that the FMCW radar echo signal after the Kth frame in the N frames of FMCW radar echo signals, that is, the K+1th frame, the K+2th frame, …, the N-1th frame, and the Nth frame of FMCW radar echo signals in the N frames of FMCW radar echo signals.

[0063] It can be understood that after the processing step is performed on any frame of FMCW radar echo signal after the Kth frame, the third signal corresponding to the frame of FMCW radar echo signal and the corresponding target distance gate can be obtained; and the processing step is performed on the K+1th to Nth frames of FMCW radar echo signals respectively, and N-K third signals corresponding to the K+1th to Nth frames of FMCW radar echo signals respectively and N-K target distance gates corresponding respectively can be obtained.

[0064] The processing step includes S1031 and S1033.

[0065] S1031, updating the anchor distance gate according to the target distance gate corresponding to the last frame of FMCW radar echo signal of the current frame of FMCW radar echo signal.

[0066] Exemplarily, the current frame of FMCW radar echo signal can be the FMCW radar echo signal currently performing the processing step, and the last frame of FMCW radar echo signal of the current frame of FMCW radar echo signal can be the last frame of FMCW radar echo signal of the FMCW radar echo signal currently performing the processing step.

[0067] For example, when the processing step is performed on the K+2th frame of FMCW radar echo signal, the anchor distance gate can be updated to the target distance gate corresponding to the last frame (i.e., the K+1th frame) of FMCW radar echo signal of the K+2th frame.

[0068] It should be noted that when the processing step is performed on the K+1th frame of FMCW radar echo signal, the last frame of FMCW radar echo signal (i.e., the Kth frame of FMCW radar echo signal) has not been processed, and thus the Kth frame of FMCW radar echo signal does not have a corresponding target distance gate, and when the processing step is performed on the K+1th frame of FMCW radar echo signal, the anchor distance gate does not need to be updated, that is, S1031 does not need to be performed.

[0069] S1032, determining the target distance gate where the human body is located according to the plurality of first signals and the anchor distance gate.

[0070] Specifically, determining the target distance gate where the human body is located according to the plurality of first signals and the anchor distance gate includes:

[0071] According to the plurality of first signals, after fast Fourier transform is performed along the distance dimension, fast Fourier transform is performed along the slow time dimension to obtain a plurality of third Doppler-range spectra; and according to the plurality of third Doppler-range spectra and the anchor distance gate, a target distance gate is determined.

[0072] Exemplarily, for any frame of FMCW radar echo signals after the Kth frame, the number of corresponding first signals and corresponding third Doppler-range spectra is the same, and the plurality of first signals and the plurality of third Doppler-range spectra obtained are one-to-one corresponding.

[0073] Specifically, according to the plurality of third Doppler-range spectra and the anchor distance gate, the target distance gate is determined, including:

[0074] According to the plurality of third Doppler-range spectra, a target motion speed of human walking is determined; according to the anchor distance gate and the target motion speed, a distance gate range is determined; and according to the distance gate range and the plurality of third Doppler-range spectra, the target distance gate is determined.

[0075] Exemplarily, for any third Doppler-range spectrum, an angular frequency corresponding to a maximum peak in the third Doppler-range spectrum can be determined, and then according to an FMCW speed measurement formula, a speed corresponding to the angular frequency is determined, and the speed corresponding to the angular frequency is determined as a motion speed of human walking corresponding to the third Doppler-range spectrum; wherein the FMCW speed measurement formula can be as shown in the following formula (1):

[0076] (1)

[0077] In formula (1), represents the speed of the object (in the application scenario of the present application, the FMCW speed measurement formula is used to determine the speed of human walking, and when applied to the present application, may represent the motion speed of human walking, is the wavelength of the FMCW radar, is the angular frequency, is the time length of one linear frequency modulation signal (i.e., the time length of one first signal).

[0078] Exemplarily, after the plurality of motion speeds corresponding to the plurality of third Doppler-range spectra are obtained, an average value of the plurality of motion speeds corresponding to the plurality of third Doppler-range spectra can be determined as the target motion speed.

[0079] It should be noted that the above manner of determining the average value of the plurality of motion speeds corresponding to the plurality of third Doppler-range spectra as the target motion speed is only an example, and a person skilled in the art can also determine the target motion speed by other manners, which will not be described herein.

[0080] Exemplarily, the range gate can be determined according to a range gate determination formula; wherein the range gate determination formula can be shown as formula (2) as follows:

[0081] (2)

[0082] In formula (2), denotes a minimum range gate of the range gate corresponding to the K+jth frame of FMCW radar echo signal, is a positive integer, denotes a maximum range gate of the range gate corresponding to the K+jth frame of FMCW radar echo signal, denotes a target range gate corresponding to the K+j-1th frame of FMCW radar echo signal, denotes a variable speed protection coefficient (1.2 generally can be taken), denotes a target motion speed corresponding to the K+jth frame of FMCW radar echo signal, denotes a frame period of the FMCW radar echo signal, denotes a unit length of the range gate, denotes taking an absolute value, denotes rounding up.

[0083] It should be noted that for the K+1th frame of FMCW radar echo signal, i.e. the range gate determination formula can be shown as formula (3) as follows:

[0084] (3)

[0085] In formula (3), is an anchor range gate that has not been updated (i.e. the anchor range gate determined by S102).

[0086] Exemplarily, peak value search can be performed in a third Doppler-range spectrum between the minimum range gate and the maximum range gate, and a range gate corresponding to the peak value is determined as the target range gate.

[0087] In this way, the target range gate can be quickly and accurately determined according to the anchor range gate and the third Doppler-range spectrum.

[0088] S1033, determining a third signal according to the plurality of first signals and the target range gate.

[0089] The third signal is an average signal of the first signal located in the target range gate.

[0090] Specifically, the third signal is determined according to the plurality of first signals and the target range gate, comprising:

[0091] ​The first signal is subjected to fast Fourier transform in the distance dimension, and the third signal is obtained by adding and averaging the first signal in the target distance gate.

[0092] The third signal can be determined by the following formula (4) for example:

[0093] (4)

[0094] In formula (4), represents the first signal data subjected to fast Fourier transform in the distance dimension in the i th distance gate and the j th slow time dimension; the i th distance gate is the target distance gate; represents the number of the first signals in the FMCW radar echo signal; represents the third signal.

[0095] The third signal is a complex signal, and the real part and the imaginary part of the complex signal constitute the real phase information of the radar intermediate frequency signal. The phase value of the third signal can be calculated by using the arctangent demodulation.

[0096] The phase value of the third signal can be determined by using the following formula (5) for example:

[0097] (5)

[0098] In formula (5), represents the phase value of the third signal, is the in-phase branch of the phase signal, is the quadrature branch of the phase signal.

[0099] The phase value of the third signal can also be determined by using the DACM demodulation algorithm. The DACM demodulation algorithm is a common technical means for determining the phase value of a signal by those skilled in the art, and the calculation process is not described here.

[0100] In this way, the third signal and the phase value can be accurately determined according to the first signal and the target distance gate.

[0101] S104, determining a plurality of second signals according to a plurality of third signals and a plurality of target distance gates.

[0102] The second signal is the third signal after the human walking interference is eliminated.

[0103] Specifically, the plurality of second signals are determined according to the plurality of third signals and the plurality of target distance gates, including:

[0104] ​​​The phase values ​​of multiple third signals are unwrapped to obtain multiple first phases; multiple second phases are determined based on the multiple first phases and multiple target distance gates; multiple second signals are determined based on the multiple second phases and multiple third signals.

[0105] For example, the second phase corresponding to the third signal can be determined by using the human motion phase elimination formula based on the first phase and the target distance gate corresponding to the third signal corresponding to the first phase.

[0106] It is understandable that multiple third signals correspond one-to-one with multiple first phases, multiple first phases correspond one-to-one with multiple second phases, and multiple second phases correspond one-to-one with multiple second signals.

[0107] For example, the human motion phase elimination formula can be shown in the following equation (6):

[0108] (6)

[0109] In equation (6), Indicates the first The second phase corresponding to the third signal And it is a positive integer. Indicates the first The first phase corresponding to the third signal. For the wavelength of the FMCW radar, Indicates the unit length of the distance gate. This represents the target range gate corresponding to the FMCW radar echo signal in frame K+j-1.

[0110] It should be noted that for the (K+1)th frame of the FMCW radar echo signal, i.e. At that time, the human motion phase elimination formula can be expressed as follows (7):

[0111] (7)

[0112] In equation (7), This is the anchor distance gate that has not been updated (i.e., the anchor distance gate determined in S102).

[0113] For example, the phase value of the corresponding third signal can be updated according to multiple second phases to obtain multiple second signals.

[0114] In this way, the second signal can be accurately determined based on multiple third signals and multiple target distance gates.

[0115] S105. Determine the respiratory rate and heart rate based on multiple second signals.

[0116] Exemplarily, before performing S105, the plurality of second signals can also be filtered by a band-pass filter with a frequency range of 0.2Hz to 2.5Hz to filter out noise, so as to improve the accuracy of the subsequent processing results.

[0117] Specifically, determining the respiratory frequency and the heartbeat frequency according to the plurality of second signals can include:

[0118] Determining a first-order phase difference signal according to the plurality of second signals, and determining the respiratory frequency and the heartbeat frequency according to the first-order phase difference signal.

[0119] Exemplarily, the first-order phase difference can be performed on each second signal to obtain the first-order phase difference signal.

[0120] Exemplarily, the respiratory frequency and the heartbeat frequency can be determined by, for example, a wavelet packet transform algorithm, a Variational Modal Decomposition (VMD) algorithm, or a Variational Mode Extraction (VME) algorithm. Determining the respiratory frequency and the heartbeat frequency by the wavelet packet transform algorithm, the VMD algorithm, or the VME algorithm all belong to the conventional technical means in the field, and will not be described here.

[0121] Further, determining the respiratory frequency and the heartbeat frequency according to the first-order phase difference signal can include:

[0122] Performing a fast Fourier transform on the first-order phase difference signal to determine the respiratory frequency, and determining the heartbeat frequency according to the first-order phase difference signal by a target algorithm.

[0123] The target algorithm is an Improved Complete Ensemble Empirical Mode Decomposition with Adaptive Noise (ICEEMDAN) algorithm.

[0124] Exemplarily, the frequency corresponding to the peak value of the first-order phase difference signal after the fast Fourier transform can be determined as the respiratory frequency.

[0125] Exemplarily, before determining the heartbeat frequency according to the first-order phase difference signal by the target algorithm, the first-order phase difference signal can be further filtered by a band-pass filter with a frequency range of 0.8Hz to 2.5Hz to reduce the complexity of processing by the target algorithm.

[0126] It should be noted that the ICEEMDAN algorithm is prior art, and its calculation iteration process will not be described here.

[0127] It can be understood that a plurality of intrinsic mode function (IMF) components and a residual signal can be obtained through the ICEEMDAN algorithm. The fast Fourier transform is performed on all the IMF components, the IMF components with a frequency between 0.8 Hz and 2.5 Hz and not being a harmonic of the respiratory signal after the fast Fourier transform are determined as target components, and the heartbeat frequency can be obtained by performing peak value search on the target components after the fast Fourier transform.

[0128] In this way, the respiratory frequency and the heartbeat frequency can be more accurately determined according to the plurality of second signals.

[0129] In S106, the respiratory frequency and the heartbeat frequency are sent to the host computer to monitor the vital signs of the human body.

[0130] After obtaining the respiratory frequency and the heartbeat frequency, the respiratory frequency and the heartbeat frequency can be sent to the host computer, and the host computer can obtain the respiratory rate and the heartbeat rate of the human body per minute through simple calculation to monitor the vital signs of the human body, which will not be described here.

[0131] The embodiment of the present application determines an anchor distance gate according to the first K frames of FMCW radar echo signals in the N frames of FMCW radar echo signals, performs processing steps on the N frames of FMCW radar echo signals respectively to obtain a plurality of third signals and a plurality of target distance gates, determines a plurality of second signals according to the plurality of third signals and the plurality of target distance gates, wherein the second signal is the third signal after eliminating the target motion phase, and determines the respiratory frequency and the heartbeat frequency according to the plurality of second signals. The respiratory frequency and the heartbeat frequency can be quickly and accurately determined by eliminating the second signal of the human body walking interference, the problem that the existing technology can be applied to limited scenarios and is difficult to accurately monitor the vital signs of the human body in the walking state is solved, the application scenarios of vital sign monitoring are expanded, and the accuracy of vital sign monitoring is improved.

[0132] Although the present application provides method operation steps such as embodiments or flowcharts, more or fewer operation steps can be included based on conventional or non-inventive labor. The order of steps listed in the embodiment is only one of the many execution orders, and does not represent the only execution order. When the device or client product is executed in practice, the method order shown in the embodiment or the drawing can be executed in sequence or in parallel (for example, in a parallel processor or multi-thread processing environment).

[0133] As shown in Figure 2 The embodiment of the present application also provides a vital sign monitoring device in a walking state. The device comprises a receiving module 201, a first processing module 202, a second processing module 203, a determining module 204 and a monitoring module 205.

[0134] The receiving module 201 is configured to receive N frames of FMCW radar echo signals, wherein each frame of FMCW radar echo signals comprises a plurality of first signals, and N is a positive integer.

[0135] The first processing module 202 is configured to determine an anchor distance gate according to K frames of FMCW radar echo signals in the N frames of FMCW radar echo signals, K being a positive integer and smaller than N.

[0136] The second processing module 203 is configured to perform a processing step on each frame of FMCW radar echo signal after the Kth frame in the N frames of FMCW radar echo signals, respectively, to obtain a plurality of third signals and a plurality of target distance gates, the plurality of third signals and the plurality of target distance gates corresponding to each other.

[0137] The determining module 204 is configured to determine a plurality of second signals according to the plurality of third signals and the plurality of target distance gates, wherein the second signal is a third signal in which human walking interference is eliminated.

[0138] The monitoring module 205 is configured to determine a breathing frequency and a heartbeat frequency according to the plurality of second signals, and send the breathing frequency and the heartbeat frequency to a host computer to monitor vital signs of the human body.

[0139] The processing step comprises: updating the anchor distance gate according to a target distance gate corresponding to a previous frame of FMCW radar echo signal; determining a target distance gate in which the human body is located according to the plurality of first signals and the anchor distance gate; and determining a third signal according to the plurality of first signals and the target distance gate, the third signal being an average signal of the first signals located in the target distance gate.

[0140] The beneficial effects and specific implementation manners of the device embodiment can refer to the foregoing method embodiments, and will not be described here again.

[0141] Some of the modules in the device described in the present application can be described in the general context of computer-executable instructions, such as program modules, which are executed by computers. Generally, program modules include routines, programs, objects, components, data structures, classes, and the like, which perform particular tasks or implement particular abstract data types. The present application can also be practiced in distributed computing environments where tasks are performed by remote processing devices that are connected through a communication network. In a distributed computing environment, program modules can be located in both local and remote computer storage media including storage devices.

[0142] The apparatuses or modules illustrated in the above application examples can be implemented by computer chips or entities, or by products with certain functions. For the convenience of description, the above apparatuses are described as various modules with functions. In the implementation of the application examples, the functions of the modules can be implemented in one or more software and / or hardware. Of course, the modules with certain functions can also be implemented by a combination of multiple sub-modules or sub-units.

[0143] The methods, apparatuses or modules described in the present application can be implemented in a computer readable program code in any appropriate manner, for example, the controller can take the form of, for example, a microprocessor or processor and a computer readable medium storing computer readable program code (such as software or firmware) executable by the (micro) processor, logic gates, switches, application specific integrated circuits (Application Specific Integrated Circuit; abbreviated as: ASIC), programmable logic controllers and embedded microcontrollers, examples of the controller include but are not limited to the following microcontrollers: ARC 625D, Atmel AT91SAM, Microchip PIC18F26K20 and Silicone Labs C8051F320, the memory controller can also be implemented as part of the control logic of the memory. Those skilled in the art also know that in addition to implementing the controller in a pure computer readable program code, the same function can also be implemented by logically programming the method steps in the form of logic gates, switches, application specific integrated circuits, programmable logic controllers and embedded microcontrollers. Therefore, such a controller can be considered as a hardware component, and the devices included therein for implementing various functions can also be considered as structures within the hardware component. Alternatively, the devices for implementing various functions can also be considered as both software modules implementing the method and structures within the hardware component.

[0144] The embodiments of the present application also provide a device, which comprises: a processor; a memory for storing processor executable instructions; and the processor executes the executable instructions to implement the method as described in the embodiments of the present application.

[0145] The embodiments of the present application also provide a non-volatile computer readable storage medium, which stores a computer program or instructions, and when the computer program or instructions are executed, the method as described in the embodiments of the present application is implemented.

[0146] In addition, the functional modules in each of the embodiments of the present application can be integrated in one processing module, or each module can exist independently, or two or more modules can be integrated in one module.

[0147] The storage medium described above includes, but is not limited to, a random access memory (RAM), a read-only memory (ROM), a cache, a hard disk (HDD), or a memory card. The storage medium can be used to store computer program instructions.

[0148] From the above description of the embodiments, those skilled in the art can clearly understand that the present application can be implemented by means of software and the necessary hardware. Based on such an understanding, the technical solutions of the present application can be embodied in the form of a software product or can be embodied in the form of data migration during implementation. The computer software product can be stored in a storage medium, such as a ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions for causing a computer device (which can be a personal computer, a mobile terminal, a server, or a network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0149] The various embodiments in the specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments. The entire or part of the present application can be used in many general or special computer system environments or configurations. For example: personal computers, server computers, handheld devices or portable devices, tablet devices, mobile communication terminals, multi-processor systems, microprocessor-based systems, programmable electronic devices, network PCs, small computers, large computers, distributed computing environments including any of the above systems or devices, etc.

[0150] The above embodiments are only used to illustrate the technical solutions of the present application, and not to limit the present application; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the present application.

Claims

1. A method of monitoring vital signs in a walking state, characterized by, The method comprises the following steps: receiving N frames of FMCW radar echo signals, wherein each frame of FMCW radar echo signal comprises a plurality of first signals, and N is a positive integer; determining an anchor distance gate according to the first K frames of FMCW radar echo signals in the N frames of FMCW radar echo signals, K being a positive integer and smaller than N; performing a processing step on each frame of FMCW radar echo signal after the Kth frame of FMCW radar echo signal in the N frames of FMCW radar echo signals to obtain a plurality of third signals and a plurality of target distance gates, the plurality of third signals corresponding to the plurality of target distance gates one by one; determining a plurality of second signals according to the plurality of third signals and the plurality of target distance gates, wherein the second signal is a third signal eliminating human walking interference; determining a breathing frequency and a heartbeat frequency according to the plurality of second signals; sending the breathing frequency and the heartbeat frequency to an upper computer to monitor the vital signs of the human body; wherein the processing step comprises: updating the anchor distance gate according to the target distance gate corresponding to the last frame of FMCW radar echo signal of the current frame of FMCW radar echo signal; determining a target distance gate in which the human body is located according to a plurality of first signals and the anchor distance gate; determining a third signal according to a plurality of first signals and a target distance gate, the third signal being an average signal of the first signals located in the target distance gate.

2. The method of claim 1, wherein, The method comprises the following steps: performing fast Fourier transform on the plurality of first signals corresponding to the first K frames of FMCW radar echo signals respectively along the distance dimension, then performing fast Fourier transform along the slow time dimension to obtain a plurality of first Doppler-distance spectra; superimposing the plurality of first Doppler-distance spectra to obtain a second Doppler-distance spectrum; determining the anchor distance gate according to the second Doppler-distance spectrum.

3. The method of claim 1, wherein, The method comprises the following steps: performing fast Fourier transform on a plurality of first signals along the distance dimension, then performing fast Fourier transform along the slow time dimension to obtain a plurality of third Doppler-distance spectra; determining a target distance gate according to the plurality of third Doppler-distance spectra and the anchor distance gate.

4. The method of claim 3, wherein, The method comprises the following steps: determining a target motion speed of human walking according to the plurality of third Doppler-distance spectra; determining a distance gate range according to the anchor distance gate and the target motion speed; determining a target distance gate according to the distance gate range and the plurality of third Doppler-distance spectra.

5. The method of claim 1, wherein, The method comprises the following steps: performing fast Fourier transform on a plurality of first signals along the distance dimension, then adding and averaging the first signals located in the target distance gate along the slow time dimension to obtain a third signal; determining a phase value of the third signal by using arctangent demodulation according to the third signal.

6. The method of claim 1, wherein, The method comprises the following steps: Unwinding the phase values of the plurality of third signals to obtain a plurality of first phases; Determine a plurality of second phases according to the plurality of first phases and the plurality of target range gates; Determine the plurality of second signals according to the plurality of second phases and the plurality of third signals.

7. The method of claim 1, wherein, The determining of the respiratory frequency and the heartbeat frequency according to the plurality of second signals comprises: Determine a first-order phase difference signal according to the plurality of second signals; Determine the respiratory frequency and the heartbeat frequency according to the first-order phase difference signal.

8. The method of claim 7, wherein, The determining of the respiratory frequency and the heartbeat frequency according to the first-order phase difference signal comprises: Determine the respiratory frequency by performing fast Fourier transform on the first-order phase difference signal; Determine the heartbeat frequency by a target algorithm according to the first-order phase difference signal, wherein the target algorithm is an improved adaptive noise complete ensemble empirical mode decomposition algorithm.

9. A walking state vital sign monitoring device, characterized by, Comprise: A receiving module configured to receive N frames of FMCW radar echo signals, wherein each frame of FMCW radar echo signals comprises a plurality of first signals, and N is a positive integer; A first processing module configured to determine an anchor range gate according to the first K frames of FMCW radar echo signals in the N frames of FMCW radar echo signals, wherein K is a positive integer and less than N; A second processing module configured to perform a processing step on each frame of FMCW radar echo signals after the Kth frame in the N frames of FMCW radar echo signals to obtain a plurality of third signals and a plurality of target range gates, wherein the plurality of third signals correspond to the plurality of target range gates one by one; A determining module configured to determine a plurality of second signals according to the plurality of third signals and the plurality of target range gates, wherein the second signals are third signals with human walking interference eliminated; A monitoring module configured to determine a respiratory frequency and a heartbeat frequency according to the plurality of second signals, and send the respiratory frequency and the heartbeat frequency to an upper computer to monitor the vital signs of a human body; The processing step comprises: Updating the anchor range gate according to a target range gate corresponding to a last frame of FMCW radar echo signals of a current frame of FMCW radar echo signals; Determining a target range gate where a human body is located according to a plurality of first signals and the anchor range gate; Determining a third signal according to a plurality of first signals and a target range gate, wherein the third signal is an average signal of the first signals located in the target range gate.

10. A device for performing a vital signs monitoring method of a walking state, characterized in that, Comprise: A processor; A memory for storing processor-executable instructions; The processor executes the executable instructions to implement the method of any one of claims 1 to 8.

Images