Adaptive physiological information detection method and system
阅读说明：本技术 适应性生理信息检测方法与系统 (Adaptive physiological information detection method and system ) 是由 王希文 于 2019-09-24 设计创作，主要内容包括：一种适应性生理信息检测方法,包含(a)接收预设第一期间的多个状态,其中状态可为静止、移动或离开；(b)根据第一期间的状态的比例,以检测第一期间内是否受到环境的干扰；(c)如果检测第一期间受到环境的干扰,则接收预设第二期间的多个状态,其中第二期间异于第一期间；(d)如果检测第一期间未受到环境的干扰,则决定优化的状态为静止；(e)根据第二期间的所述多个状态的动态变化,以决定优化的状态为移动或离开；(f)当决定的优化状态为静止或移动时,则接收预设第三期间的多个生理信息；及(g)处理第三期间的所述多个生理信息,以得到优化状态的相应生理信息。(An adaptive physiological information detection method comprises (a) receiving a plurality of states of a preset first period, wherein the states can be static, moving or leaving; (b) detecting whether the first period is interfered by the environment according to the proportion of the state of the first period; (c) if the first period is detected to be interfered by the environment, receiving a plurality of states of a preset second period, wherein the second period is different from the first period; (d) if the first period is detected not to be interfered by the environment, the optimized state is determined to be static; (e) determining the optimized state to be moving or leaving according to the dynamic change of the plurality of states in the second period; (f) when the determined optimization state is static or moving, receiving a plurality of pieces of physiological information in a preset third period; and (g) processing the plurality of physiological information during the third period to obtain corresponding physiological information for the optimized state.)
1. An adaptive physiological information detection method, comprising:
(a) receiving a plurality of states of a preset first period, wherein the states can be static, moving or leaving;
(b) detecting whether the first period is interfered by the environment according to the proportion of the state of the first period;
(c) if the first period is detected to be interfered by the environment, receiving a plurality of states of a preset second period, wherein the second period is different from the first period;
(d) if the first period is detected not to be interfered by the environment, the optimized state is determined to be static;
(e) determining the optimized state to be moving or leaving according to the dynamic change of the plurality of states in the second period;
(f) when the determined optimization state is static or moving, receiving a plurality of pieces of physiological information in a preset third period; and
(g) processing the plurality of physiological information during the third period to obtain corresponding physiological information of the optimized state.
2. The adaptive physiological information detecting method according to claim 1, wherein the step (b) comprises:
(b1) judging whether the proportion of the static state in the plurality of states in the first period is larger than a preset first critical value or not;
(b2) if the determination result of the step (b1) is negative, performing the step (c), otherwise, determining whether the ratio of the leaving states among the plurality of states in the first period is greater than a preset second threshold and there are few moving states; and
(b3) if the determination result of the step (b2) is positive, the step (c) is executed, otherwise, the optimized state is determined to be static.
3. The adaptive physiological information detecting method according to claim 1, wherein the step (e) comprises:
(e1) using a sliding window with a preset size to select a group of states and determining the proportion of each state in the group of states;
(e2) moving the sliding window to the next time to select another group of states and determining the proportion of each state in the other group of states; and
(e3) repeating the step (e2) a preset number of times;
wherein if the proportion of the stationary state decreases, the proportion of the moving state increases, and the proportion of the leaving state increases, then the optimized state is determined to be leaving.
4. The adaptive physiological information detecting method according to claim 1, wherein the step (g) comprises:
removing an abnormal value among the plurality of physiological information of the third period; and
a moving average method is used to process the physiological information remaining after the outliers are removed.
5. The adaptive physiological information detection method of claim 1, further comprising:
storing the optimized state and corresponding physiological information.
6. The adaptive physiological information detecting method according to claim 1, further comprising after the step (g):
(h) detecting whether the physiological information in the third period can not be normally obtained due to the movement of the person to be tested, so as to determine that the optimized state is static or moving.
7. The adaptive physiological information detecting method according to claim 6, wherein the step (h) comprises:
(h1) judging whether the value of the corresponding physiological information of the optimized state is extremely small or not;
(h2) if the determination result of the step (h1) is positive, selecting a plurality of stable physiological information in a preset fourth period, otherwise determining that the optimized state is static, wherein the fourth period is different from the third period;
(h3) processing the plurality of stable physiological information during the fourth period;
(h4) judging whether the optimization state is static or not and whether the value of the corresponding physiological information is extremely small or not; and
(h5) if the judgment result of the step (h4) is positive, the optimized state is determined to be moving, otherwise, the optimized state is determined to be static.
8. The adaptive physiological information detecting method according to claim 7, wherein the plurality of stable physiological information are selected according to a corresponding index whose value represents a signal stability of the corresponding physiological information.
9. The adaptive physiological information detecting method according to claim 1, wherein the physiological information is a heart rate or a respiration rate.
10. An adaptive physiological information detection system comprising:
a detection device;
a first-order detector for receiving the output signal of the detection device and outputting the state and physiological information of the person to be detected, wherein the state can be static, moving or leaving; and
the second-order detector receives and optimizes the state of the first-order detector and obtains corresponding physiological information according to the optimized state;
wherein the second order detector performs the steps of:
(a) receiving a plurality of states in a preset first period;
(b) detecting whether the first period is interfered by the environment according to the proportion of the state of the first period;
(c) if the first period is detected to be interfered by the environment, receiving a plurality of states of a preset second period, wherein the second period is different from the first period;
(d) if the first period is detected not to be interfered by the environment, the optimized state is determined to be static;
(e) determining the optimized state to be moving or leaving according to the dynamic change of the plurality of states in the second period;
(f) when the determined optimization state is static or moving, receiving a plurality of pieces of physiological information in a preset third period; and
(g) processing the plurality of physiological information during the third period to obtain corresponding physiological information of the optimized state.
11. The adaptive physiological information detecting system according to claim 10, wherein the detecting device comprises a radar that transmits radio frequency signals to the subject and receives reflected radio frequency signals.
12. The adaptive physiological information sensing system of claim 10 wherein the step (b) comprises:
(b1) judging whether the proportion of the static state in the plurality of states in the first period is larger than a preset first critical value or not;
(b2) if the determination result of the step (b1) is negative, performing the step (c), otherwise, determining whether the ratio of the leaving states among the plurality of states in the first period is greater than a preset second threshold and there are few moving states; and
(b3) if the determination result of the step (b2) is positive, the step (c) is executed, otherwise, the optimized state is determined to be static.
13. The adaptive physiological information sensing system of claim 10 wherein the step (e) comprises:
(e1) using a sliding window with a preset size to select a group of states and determining the proportion of each state in the group of states;
(e2) moving the sliding window to the next time to select another group of states and determining the proportion of each state in the other group of states; and
(e3) repeating the step (e2) a preset number of times;
wherein if the proportion of the stationary state decreases, the proportion of the moving state increases, and the proportion of the leaving state increases, then the optimized state is determined to be leaving.
14. The adaptive physiological information sensing system of claim 10 wherein the step (g) comprises:
removing an abnormal value among the plurality of physiological information of the third period; and
a moving average method is used to process the physiological information remaining after the outliers are removed.
15. The adaptive physiological information detection system of claim 10, further comprising:
storing the optimized state and corresponding physiological information.
16. The adaptive physiological information detecting system of claim 10, further comprising after the step (g):
(h) detecting whether the physiological information in the third period can not be normally obtained due to the movement of the person to be tested, so as to determine that the optimized state is static or moving.
17. The adaptive physiological information sensing system of claim 16, wherein the step (h) comprises:
(h1) judging whether the value of the corresponding physiological information of the optimized state is extremely small or not;
(h2) if the determination result of the step (h1) is positive, selecting a plurality of stable physiological information in a preset fourth period, otherwise determining that the optimized state is static, wherein the fourth period is different from the third period;
(h3) processing the plurality of stable physiological information during the fourth period;
(h4) judging whether the optimization state is static or not and whether the value of the corresponding physiological information is extremely small or not; and
(h5) if the judgment result of the step (h4) is positive, the optimized state is determined to be moving, otherwise, the optimized state is determined to be static.
18. The adaptive physiological information detection system of claim 17, wherein the plurality of stable physiological information is selected according to a corresponding indicator, wherein a value of the indicator indicates a signal stability of the corresponding physiological information.
19. The adaptive physiological information sensing system of claim 10 wherein the physiological information is a heart rate or a respiration rate.
20. The adaptive physiological information detection system of claim 10, wherein the detection device is a non-contact detection device or a contact detection device.
Technical Field
The present invention relates to a method for detecting physiological information, and more particularly, to an adaptive method for detecting physiological information suitable for a contact or non-contact detection device.
Background
Body Temperature (BT), Blood Pressure (BP), Heart Rate (HR) and Respiration Rate (RR) are four major physiological information (visual signals). The detection of physiological information can be used to assess the health of the body and can provide clues to the disease.
Conventional medical detection devices can be classified into contact (contact) and non-contact (non-contact) types. A contact detection device, such as a bracelet (Xiaomi band), can be worn on the body by a sensor to collect physiological information (e.g., heart rate). The non-contact detection means for example sense a radar, emit a radio frequency signal by means of the radar and analyze the reflected radio frequency signal for physiological information (e.g. heart rate or breathing rate).
Wearable (contact) detection devices are limited in computing power and therefore do not allow further processing of the collected physiological information. Although the non-contact detection device has strong calculation capability, it is easily interfered by environmental noise (noise), so that the state is often misjudged or frequently switched.
Therefore, it is desirable to provide a novel mechanism for improving the shortcomings of conventional contact or non-contact medical detection devices.
Disclosure of Invention
In view of the foregoing, an objective of the embodiments of the invention is to provide an adaptive physiological information detection method, which can be applied to a contact or non-contact detection device to obtain more accurate and stable physiological information.
According to an embodiment of the invention, the adaptive physiological information detection method comprises the following steps: (a) receiving a plurality of (complex) states of a preset first period, wherein the states can be static, moving or leaving; (b) detecting whether the first period is interfered by the environment according to the proportion of the state of the first period; (c) if the first period is detected to be interfered by the environment, receiving a plurality of states of a preset second period, wherein the second period is different from the first period; (d) if the first period is detected not to be interfered by the environment, the optimized state is determined to be static; (e) determining the optimized state to be moving or leaving according to the dynamic change of the plurality of states in the second period; (f) when the determined optimization state is static or moving, receiving a plurality of pieces of physiological information in a preset third period; and (g) processing the plurality of physiological information during the third period to obtain corresponding physiological information for the optimized state.
Drawings
FIG. 1 is a block diagram of an adaptive physiological information detection system according to an embodiment of the present invention.
Fig. 2 shows a flow chart of an adaptive physiological information detection method performed by the second-order detector of fig. 1.
Fig. 3 illustrates a plurality of states during the second period.
Fig. 4 illustrates a polarization signal, a detection state of a first-order detector, and a detection state of a second-order detector.
Fig. 5 illustrates a polarization signal, a detection state of a first-order detector, and a detection state of a second-order detector.
FIG. 6 illustrates several cases of using sliding windows and state ratios to determine the optimal state
[ List of reference numerals ]
100 adaptive physiological information detection system
11 detection device
12 first order detector
13 storage device
14 second order detector
15 display
200 adaptive physiological information detection method
21 receive the status of the first period
22 determining whether the ratio of the static state is greater than a first threshold
23 receive the status of the second period
24 determining whether the ratio of the in-open state is greater than a second threshold and the state of little movement
25 determining the optimized state based on the dynamic change of the state
Receiving 26 physiological information of a third period
27 processing physiological information
28 determining whether the physiological information is minimal
29 receiving stable physiological information during a fourth period
30 processing stabilized physiological information
31 judging whether the state is still and the physiological information is extremely small
32 store status and physiological information
41 false positive
300 sliding window
I in-phase polarized signal
Q-orthogonally polarized signal
Detailed Description
Fig. 1 shows a system block diagram of an adaptive physiological information (digital-sign) detection system 100 according to an embodiment of the present invention, which can be used to detect physiological information, such as Heart Rate (HR) or Respiratory Rate (RR).
In the present embodiment, the adaptive physiological information detecting system (hereinafter referred to as detecting system) 100 may include a detecting device 11, which may be a non-contact type or a contact type. In one embodiment, the (non-contact) detection device 11 may include a radar, and may transmit a Radio Frequency (RF) signal to the dut, receive a reflected RF signal, and convert the RF signal to obtain an in-phase (polarization) signal I and a quadrature (quadrature) polarization signal Q. The radar of this embodiment may be a continuous-wave (CW) radar or an ultra-wideband (UWB) radar (e.g., a Frequency Modulated Continuous Wave (FMCW) radar). In another embodiment, the (contact) detection device 11 may be a wearable detection device (e.g., a smart bracelet/watch, a wrist or arm sphygmomanometer, a smart garment/pants, etc.), an electrocardiogram electrode patch, an inductive floor mat, a touch sensing device, a finger physiological information sensing device, etc. The detection device 11 may comprise a sensor for obtaining a signal related to the physiological information. Although the following embodiments exemplify a non-contact radar as the detection device 11, the embodiments of the present invention are also applicable to a contact detection device 11.
The detection system 100 of the present embodiment may include a first-stage (stage) detector 12, which receives output signals (e.g., an in-phase polarization signal I and a quadrature polarization signal Q) of the detection device 11 to output status and physiological information (e.g., a Heart Rate (HR) and a Respiratory Rate (RR)) of the subject. In the present embodiment, the states can be classified into the following three types: rest (e.g. sleeping or resting), move (motion), leave (leave). In one example, rest, move, and leave correspond to state values of 4, 2, and 0, respectively. In one embodiment, each piece (group) of physiological information outputted by the first-order detector 12 may be additionally added with an index for indicating the signal stability (stability) of the corresponding physiological information.
The detection system 100 of the present embodiment may include a storage device (memory device) 13, such as a Static Random Access Memory (SRAM) or a Dynamic Random Access Memory (DRAM), for storing the status and physiological information output by the first-stage detector 12.
The detection system 100 of the present embodiment may comprise a second-order detector 14, which receives and optimizes (optimize) the state of the first-order detector 12 to obtain corresponding physiological information (e.g. heart rate and respiratory rate) according to the optimized state. The optimized state and physiological information output by the second-order detector 14 can be stored in the storage device 13.
The detection system 100 of the present embodiment may include a display 15 for displaying the optimized state and the physiological information outputted from the second-level detector 14 or the optimized state and the physiological information stored in the storage device 13.
In this embodiment, the first-order detector 12 and the second-order detector 14 may be two different processing devices. Alternatively, in another embodiment of the present disclosure, the first-order detector 12 and the second-order detector 14 may be integrated into the same processing device. The Processing device may be, for example, a general-purpose Processor, a Micro-Control Unit (MCU), a Digital Signal Processor (DSP), and/or a Neural Processing Unit (NPU), and includes various logic circuits for providing data Processing and operation functions, storing and reading data in the storage device 13, and transmitting frame data to the display 15.
Fig. 2 shows a flowchart of an adaptive physiological information detection method (hereinafter referred to as a detection method) 200 executed by the second-order detector 14 of fig. 1. In step 21, a plurality of states of a predetermined first period (e.g., the last 30 seconds) are received. Next, according to one of the features of the present embodiment, in steps 22 and 24, whether the first period is interfered by the environment is detected according to the ratio (percentage) of the states (of the first period), which is described in detail below.
In step 22, it is determined whether the ratio of the plurality of states (of the first period) having the static state is greater than a predetermined first threshold (e.g., 60%). The magnitude of the first threshold may be determined according to the application. For example, if the interference of the application environment is large, the first critical value may be preset to a small value. If the determination result in step 22 is negative (indicating that the moving state and the leaving state occupy most of the first period and are likely to be interfered by the environment), step 23 is entered, and a plurality of states of a preset second period are received instead, where the preset second period is different from the preset first period. In one embodiment, the predetermined second period (e.g., 60 seconds) is greater than the predetermined first period (e.g., 30 seconds).
If the determination result in step 22 is positive, step 24 is entered to further determine whether the ratio of the states (of the first period) is greater than a predetermined second threshold (e.g. 25%) and there are few moving states (i.e. the ratio of the moving states is zero or close to zero or less than a predetermined threshold). If the result of the determination in step 24 is positive (indicating that the dut may leave but the dut is not moving before leaving and is likely to be interfered by the environment), step 23 is entered, and a plurality of states of the preset second period are received instead. If the determination at step 24 is negative, the optimized state is determined to be static. The order of execution of steps 22 and 24 may be reversed.
After receiving the plurality of states for the predetermined second period (step 23), step 25 is entered to determine the optimized state. According to another feature of this embodiment, step 25 determines whether the optimized state is to be moved or left based on the dynamic (or time-dependent) change of the plurality of states (during the second period). Fig. 3 illustrates a plurality of states during the second period, wherein the state values 4, 2, 0 represent stationary, moving, and leaving, respectively. As shown in fig. 3, a group of states is circled (framed) in time order using a sliding window 300 having a predetermined size (e.g., 4) and the ratio of each state in the group of states is determined. The sliding window 300 is then moved to the next time to circle another set of states and determine the ratio of the states in the other set of states. The predetermined times are executed according to the principle. In one embodiment, the size of the sliding window 300 may be half of the total number of states in the predetermined second period. Generally, the smaller the sliding window 300, the more accurate the results obtained (but at a slower processing speed); conversely, the larger the sliding window 300, the faster the processing speed (but the less accurate the results obtained).
In the example shown in fig. 3, the scale of the stationary state is decreased, the scale of the moving state is increased, and the scale of the departing state is increased, indicating that the subject is initially sleeping or resting (stationary state), then getting up (moving state), and finally departing from the detection range (departing state). If this trend is met, the optimized state can be determined to be left, and then step 32 is entered for storing (optimizing) the state and corresponding physiological information, for example, in the storage device 13; otherwise, the optimized state is determined to be moving.
According to one of the features of the present embodiment described above, different periods (e.g., the first period or the second period) are used adaptively to receive the states depending on the ratio of the states (steps 22, 24). Therefore, the misjudgment of the state caused by the environmental interference can be reduced. Fig. 4 illustrates the polarization signal I/Q, the detection state of the first-order detector 12, and the detection state of the second-order detector 14. In this example, the first order detector 12 generates a false positive 41, false positive for the stationary condition as leaving. However, the second-order detector 14 can avoid this false determination 41.
According to another feature of the present embodiment, the sliding window 300 is used to correctly determine whether the optimized state is exit (step 25). Fig. 5 illustrates the polarization signal I/Q, the detection state of the first-order detector 12, and the detection state of the second-order detector 14. In this example, the first-order detector 12 is susceptible to environmental noise, and the leaving state is erroneously determined to be a stationary state a plurality of times. However, the second-stage detector 14 can avoid these false positives by sliding the window 300, thereby obtaining a stable state.
FIG. 6 illustrates several scenarios for determining the optimal state using the sliding window 300 and the ratio of states. In case I, the fraction of stationary states is very small (close to or equal to 0%) and the fraction of moving states is very small (close to or equal to 0%), then the optimal state is determined to be left. In case II, the optimized state is determined to be away if the ratio of the stationary state decreases, the ratio of the moving state increases, and the ratio of the away state increases. In case III, the proportion of stationary state is very small (close to or equal to 0%), the proportion of moving state is greater than 0%, and the proportion of leaving state is greater than 0%, it is considered as the environmental interference to be ignored. In case IV, the proportion of the stationary state is greater than 0%, the proportion of the moving state is 0%, and the proportion of the leaving state is greater than 0%, it is considered that the environmental interference is ignored. In case V, if the aforementioned cases I to IV are not met, the optimization state is determined to be moving.
Returning to the detection method 200 shown in fig. 2, when the determined optimization state is static (step 24) or moving (step 25), the method proceeds to step 26, and receives a plurality of physiological information (such as Heart Rate (HR) or Respiration Rate (RR)) of a preset third period (such as 60 seconds). The relative sizes of the first period (step 21), the second period (step 23) and the third period (step 26) may vary depending on the application. In one embodiment, the detection method 200 is used to monitor the breathing and heartbeat of a newborn, and the first period is preset to be 30-40 seconds, while the second period and the third period are preset to be 60-100 seconds longer. In another embodiment, the detection method 200 is used for monitoring elderly people, and the first period is preset to be 60-90 seconds, while the second period and the third period are preset to be 30-45 seconds smaller.
Then, the physiological information (in the third period) is processed in step 27 to obtain the optimized corresponding physiological information (in one stroke). In the present embodiment, the plurality of physiological information are processed using outlier removal (outlier) and moving average (moving average). In one embodiment, outlier removal may be performed by averaging and standard deviation of the physiological information received in step 26, such as the Heart Rate (HR) or the Respiratory Rate (RR), and is performed as follows. If the physiological information Y does not satisfy the following formula, the physiological information Y is removed.
Wherein, A represents the physiological information,represents the average value of the physiological information, and X is a preset tolerance (tolerance) value (for example, 0.5-1). According to the above formula, the larger the tolerance value X is, the less abnormal values are removed; conversely, the smaller the tolerance value X, the more abnormal values are removed.
After removing the abnormal value, the present embodiment processes the remaining physiological information using the moving average method as follows.
Wherein FtIs a predicted value, i.e. the result MA of the moving averagenRepresents a moving average of n sets of physiological information; n represents the number of moving averages, that is, the number of physiological information; a. thet-iThe actual value representing the t-i th physiological information.
Then, according to another feature of the present embodiment, in steps 28 to 31, it is detected whether the physiological information in the third period cannot be normally obtained due to the movement of the subject, so as to determine whether the optimized state is still or moving, which is described in detail below.
In step 28, it is determined whether the value of the physiological information is very small (zero or close to zero or less than a predetermined threshold value). If the determination result in step 28 is positive (indicating that the physiological information in the third period may not be normally obtained due to the movement of the subject), step 29 is entered to select stable physiological information(s) in a preset fourth period, where the preset fourth period is different from the preset third period. In this embodiment, the preset fourth period (for example, 90 seconds) is greater than the preset third period (60 seconds). In the present embodiment, the stable physiological information is selected according to the corresponding index (which represents the signal stability of the corresponding physiological information), and thus the physiological information with high signal stability is selected. Next, step 30 is entered for processing the plurality of stable physiological information (of the fourth period). Step 30 may use techniques similar to step 27 to process physiological information and therefore details are not described. If the determination result in step 28 is negative (indicating that the physiological information in the third period is not affected by the movement of the subject), the optimized state is determined to be still, and step 32 is entered for storing (optimizing) the state and the corresponding physiological information, for example, in the storage device 13.
After step 30 is executed, step 31 is entered to determine whether the (optimized) state is still and the value of the physiological information is very small (zero or close to zero or less than a predetermined threshold value). If the judgment result in the step 31 is positive (indicating that the physiological information in the third period cannot be normally obtained due to the movement of the subject), the optimized state is determined to be movement; otherwise, the optimized state is determined to be static. Then, step 32 is entered, and the (optimized) state and corresponding physiological information are stored, for example, in the storage device 13.
The above description is only for the preferred embodiment of the present invention, and is not intended to limit the scope of the claims; other equivalent changes and modifications without departing from the spirit of the disclosure are intended to be included within the scope of the appended claims.