Wearable electronic device for remote heart rate measurement

Abstract

The present invention provides a wearable electronic device for remotely measuring heart rate, characterized in that it comprises: a control module, and a microwave signal transmitting and collecting module electrically connected to the control module, wherein the microwave signal transmitting and collecting module is used to transmit microwave signals and collect echo signals; the control module is used to receive multiple frames of echo signals, and perform multi-point sampling on each frame of the echo signals to obtain a sampling data matrix, confirm a one-dimensional vector with a maximum modulus value from the sampling data matrix, and determine breathing and heartbeat parameters based on a phase signal of the one-dimensional vector.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic equipment, and in particular to a wearable electronic equipment. Background Art

[0002] With the rapid development of communication technology and computer computing, wearable electronic devices that integrate multiple cutting-edge technologies are becoming more and more popular and sought after by the public. Wearable electronic devices are also gradually expanding from common communication functions to more functions, such as health monitoring functions.

[0003] Traditional health bracelets generally use sensors to identify heart rate. There are three main methods: first, based on biopotential measurement methods such as ECG (Electrocardiogram), the heart rate is obtained by measuring ECG, which is currently a relatively accurate method; second, based on PPG (photoplethysmography), it uses a photoelectric detection method to irradiate LED light into human skin tissue, and then converts the received light signal into an electrical signal through the photoelectric receiving tube at the receiving end; third, based on vibration monitoring, it uses precision accelerometers to measure mechanical impact signals generated by heart or blood vessel vibrations. Since the heart's contraction is periodic, the heart rate can be obtained by analyzing the vibration signal.

[0004] The above three ways of measuring heart rate require that the bracelet fits tightly to the wrist and the person being measured is in a relatively stable state, so the measurement accuracy is high. Once the bracelet is far away from the person being measured or in an unstable state, such as accelerating running, decelerating running, or playing basketball, the heart rate will fluctuate. If the person being measured sweats a lot due to strenuous exercise, the light absorption rate of sweat is not fixed, which will also affect the measurement accuracy. Summary of the invention

[0005] In view of the defects existing in the prior art, the object of the present invention is to provide a wearable electronic device capable of remotely measuring heart rate.

[0006] In order to achieve the above object, the specific technical solution adopted by the present invention is as follows:

[0007] A wearable electronic device for remotely measuring heart rate comprises: a control module and a microwave signal transmitting and collecting module electrically connected to the control module, wherein the microwave signal transmitting and collecting module is used to transmit microwave signals and collect echo signals; the control module is used to receive multiple frames of echo signals and perform multi-point sampling on each frame of the echo signals to obtain a sampling data matrix, confirm a one-dimensional vector with a maximum modulus value from the sampling data matrix, and determine breathing and heartbeat parameters based on a phase signal of the one-dimensional vector.

[0008] In one embodiment, the control module performs multi-point sampling on the echo signal of each frame to obtain a sampling data matrix, including: performing multi-point sampling on the echo signal of each frame, and performing Range-FFT processing on the sampled data to obtain a Range-FFT matrix; the control module determines the respiratory and heartbeat parameters based on the phase information of the one-dimensional vector, including: obtaining the respiratory and heartbeat parameters after performing FFT analysis on the phase information of the one-dimensional vector.

[0009] In one embodiment, the control module determines the respiratory and heartbeat parameters based on the phase information of the one-dimensional vector, including: calculating the phase corresponding to each complex number on the one-dimensional vector to obtain a phase vector sequence;

[0010] The phase vector sequence is unwrapped, and the unwrapped phase vector sequence is differentially processed to obtain a phase difference matrix; the phase difference matrix is ​​band-pass filtered and then subjected to the FFT analysis to obtain breathing and heartbeat parameters.

[0011] In one embodiment, the control module confirms the one-dimensional vector with the largest modulus value from the sampling data matrix, including: performing CFAR calculation on each sampling data in the sampling data matrix, if the sampling data does not meet the CFAR amplitude, it indicates that there is no target object in the echo signal, if the sampling data meets the CFAR amplitude, it indicates that there is a target object in the echo signal, and determining the largest one-dimensional vector with the largest modulus value.

[0012] In one embodiment, the control module is further used to calculate the frequency corresponding to the sampling data with the maximum modulus value, and calculate the distance between the target object and the device according to the frequency.

[0013] In one embodiment, the electronic device further includes a communication module, and the control module sends the heart rate parameter and / or the distance to other electronic devices or a server through the communication module.

[0014] In one embodiment, the electronic device further comprises a display module, and the display module is used to display the breathing and heartbeat parameters and the distance.

[0015] In one embodiment, the display module is a capacitive touch display screen.

[0016] In one embodiment, the wave signal is a radar microwave of 9.5Ghz-10.6Ghz.

[0017] In one embodiment, it also includes a micro-alarm module, which is used to issue an alarm at least when the measured heart rate parameter reaches a preset threshold.

[0018] The beneficial effects of the present invention are as follows: by integrating a wave signal emission and acquisition module in the device and performing corresponding processing and analysis on the echo signal, the breathing and heartbeat parameters of the target object can be measured even when the target object is far away from the electronic device, and when measuring the breathing and heartbeat of the target object through the echo signal, the following algorithm is used to make the measurement result more accurate, that is, collecting multiple frames of echo signals, and performing multi-point sampling on the multiple frames of echo signals, and using the phase signal of a one-dimensional vector with a maximum modulus value that can reflect the characteristics of the target object for parameter measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 It is a structural schematic diagram of a wearable electronic device for remotely measuring heart rate according to the present invention;

[0021] Figure 2 It is the respiratory and heart rate baseband processing flow. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, other embodiments obtained by ordinary technicians in this field without creative work are all within the scope of protection of the present invention.

[0023] In the description of the present invention, it should be noted that the terms "vertical", "up", "down", "horizontal", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0024] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0025] In one embodiment, Figure 1 As shown, a wearable electronic device for remotely measuring heart rate is provided, comprising: a control module 10, and a microwave signal transmitting and collecting module 20 electrically connected to the control module 10, wherein the microwave signal transmitting and collecting module 20 is used to transmit microwave signals and collect echo signals; the control module 10 is used to receive multiple frames of echo signals, and perform multi-point sampling on each frame of the echo signals to obtain a sampling data matrix, confirm a one-dimensional vector with a maximum modulus value from the sampling data matrix, and determine breathing and heartbeat parameters based on a phase signal of the one-dimensional vector.

[0026] The control module also measures the distance between the electronic device and the target object based on the echo signal.

[0027] In one embodiment, the microwave signal emitted by the microwave signal transmitting and collecting module 20 is a radar microwave of 9.5Ghz-10.6Ghz. The radar microwave also has the following parameters: Modulation Type: Triangle; Bandwidth IF: 600KHz; Main Frequency Fc: 10400MHz; Comb Notch: DC; Filter Cutoff at fnotch+ΔfΔf=0.002526*RS=15.4174Hz; Samples Per Frame: 256; RS=6103.5; Tchirp=41.94ms.

[0028] The control module has a 10-bit master MCU that supports MIPI display and heart rate and distance algorithms.

[0029] In one embodiment, the electronic device further includes a communication module 30, and the control module 10 sends the heart rate parameter and / or the distance to other electronic devices or a server via the communication module 30. The communication module 30 is a Bluetooth communication module, a wireless communication module, etc., and the other electronic device may be a mobile communication terminal.

[0030] In one embodiment, the electronic device further comprises a micro-alarm module 50, wherein the alarm module 50 is configured to issue an alarm at least when the measured heart rate parameter reaches a preset threshold.

[0031] In one embodiment, the electronic device further comprises a display module 40, and the display module 40 is used to display the heart rate parameter and the distance. The display module may be a capacitive touch display screen.

[0032] In one embodiment, Figure 2 As shown, the control module 10 performs multi-point sampling on each frame of the echo signal to obtain a sampling data matrix, including: performing multi-point sampling on each frame of the echo signal, and performing Range-FFT processing on the sampled data to obtain a Range-FFT matrix. Specifically, M frames of echo signals are collected, each frame of the signal has N sampling points, and an N-point FFT (Fast Fourier Series Transform) is performed on each frame of the signal, and an M*N Range-FFT matrix is ​​obtained after combination.

[0033] In one embodiment, the control module 10 identifies a one-dimensional vector with the maximum modulus from the sampled data matrix, and determines the respiratory and heartbeat parameters based on the phase signal of the one-dimensional vector, including: selecting a Range-bin with the maximum modulus from the M*N Range-FFT matrix, that is, the M*1 vector as the selected Range-bin, and calculating the phase corresponding to each complex number on the M*1 vector from the selected Range-bin to obtain an M*1 phase vector sequence. Further, the phase vector sequence is unwrapped, and the unwrapped phase vector sequence is differentially processed to obtain a phase differential matrix; after the phase differential matrix is ​​band-pass filtered, it is subjected to the FFT analysis to obtain the respiratory and heartbeat parameters, that is,

[0034] +->Bandpass filter of respiratory signal->fft->Frequency Range-FFT of respiratory signal->Phase unwrapping->Backward difference->|

[0035] +->Heartbeat signal bandpass filter->fft->heartbeat signal frequency

[0036] The above-mentioned unwrapping processing of the phase vector sequence is specifically as follows: starting from the second point of the original phase signal, calculate the difference between the current point and the previous point; if the difference is greater than pi, subtract 2pi from the current point and all subsequent points; if the difference is less than -pi, add 2pi to the current point and all subsequent points, and repeat the above steps until the original phase signal is traversed.

[0037] like Figure 2As shown, the above-mentioned bandpass filtering is: configuring an IIR filter with a passband frequency of 0.1-0.6 Hz and 0.4 to 4.0 Hz to perform bandpass filtering on the phase sequence after the differential operation.

[0038] In one embodiment, the control module confirms the one-dimensional vector with the largest modulus value from the sampling data matrix, including: performing CFAR calculation on each sampling data in the sampling data matrix, if the sampling data does not meet the CFAR amplitude, it indicates that there is no target object in the echo signal, if the sampling data meets the CFAR amplitude, it indicates that there is a target object in the echo signal, and determining the largest one-dimensional vector with the largest modulus value.

[0039] In one embodiment, the control module 10 is further used to calculate the frequency corresponding to the sampling data with the maximum modulus, and calculate the distance between the target object and the device according to the frequency. The distance calculation formula is: d = fb*c / 2*S = fb*c / (2*B / T) = fb*c*T / (2*B), where fb is the frequency, c is the speed of light, B is the sweep bandwidth, T is the sweep period, and S is the sweep slope.

[0040] After calculating the distance of each frame, use Alpha filtering to process it, which can increase the smoothness of the distance. Please set the specific Alpha parameters according to the actual situation. If there are targets in multiple echo signals, but there are occasionally a small number of frames without targets, the probability prediction method can be used to reduce this situation, which can be optimized later.

[0041] The present invention integrates echo signal emission and acquisition modules in the device and performs corresponding processing and analysis on the echo signal, so that the respiration and heartbeat parameters of the target object can be measured even when the target object is far away from the electronic device. When measuring the respiration and heartbeat of the target object through the echo signal, the following algorithm is adopted to make the measurement result more accurate, that is, multiple frames of echo signals are collected, and multi-point sampling is performed on the multiple frames of echo signals, and the phase signal of a one-dimensional vector with a maximum modulus value that can reflect the characteristics of the target object is used to measure the parameters.

[0042] With the above-mentioned ideal embodiments of the present invention as inspiration, through the above-mentioned description, those skilled in the art can make various changes and modifications without departing from the technical concept of the present invention. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A wearable electronic device for remotely measuring heart rate, characterized in that: include: A control module, and a microwave signal transmitting and collecting module electrically connected to the control module, wherein: The microwave signal transmitting and collecting module is used to transmit microwave signals and collect echo signals; The control module is used to receive multiple frames of echo signals, and perform multi-point sampling on each frame of the echo signals to obtain a sampling data matrix, confirm a one-dimensional vector with a maximum modulus value from the sampling data matrix, and determine the respiratory and heartbeat parameters based on the phase signal of the one-dimensional vector; wherein the control module performs multi-point sampling on each frame of the echo signals to obtain a sampling data matrix, confirms a one-dimensional vector with a maximum modulus value from the sampling data matrix, and determines the respiratory and heartbeat parameters based on the phase signal of the one-dimensional vector, including: performing multi-point sampling on each frame of the echo signals, and performing Range-FFT processing on the sampled data to obtain a Range-FFT matrix; confirming a one-dimensional vector with a maximum modulus value from the Range-FFT matrix; calculating the phase corresponding to each complex number on the one-dimensional vector to obtain a phase vector sequence; Performing an unwrapping process on the phase vector sequence, and performing a difference process on the unwrapped phase vector sequence to obtain a phase difference matrix; Using a respiratory filter to bandpass filter the phase difference matrix to obtain a respiratory frequency; The phase difference matrix is ​​band-pass filtered using a heartbeat filter, and the heartbeat frequency is determined according to the respiratory frequency and the phase difference matrix filtered by the heartbeat filter.

2. The wearable electronic device according to claim 1, characterized in that: The control module determines a one-dimensional vector having a maximum modulus value from the sampled data matrix, including: CFAR calculation is performed on each sampling data in the sampling data matrix. If the sampling data does not meet the CFAR amplitude, it indicates that no target object appears in the echo signal. If the sampling data meets the CFAR amplitude, it indicates that a target object appears in the echo signal. The largest one-dimensional vector with the largest modulus value is determined.

3. The wearable electronic device according to claim 2, characterized in that: The control module is further used to calculate the frequency corresponding to the sampling data with the maximum modulus value, and calculate the distance between the target object and the device according to the frequency.

4. The wearable electronic device according to claim 3, characterized in that: The electronic device further comprises a communication module, and the control module sends the breathing and heartbeat parameters and / or the distance to other electronic devices or a server via the communication module.

5. The wearable electronic device according to claim 3, characterized in that: The electronic device further comprises a display module, and the display module is used to display the breathing and heartbeat parameters and the distance.

6. The wearable electronic device according to claim 5, characterized in that: The display module is a capacitive touch display screen.

7. The wearable electronic device according to claim 1, characterized in that: The microwave signal is a radar microwave of 9.5Ghz-10.6Ghz.

8. The wearable electronic device according to claim 1, characterized in that: It also includes an alarm module, which is used to issue an alarm when at least the measured breathing and heartbeat parameters reach preset thresholds.

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