Wearing detection method and system for wearable device

Abstract

The present invention discloses a wearing detection method and system for a wearable device, the wearing detection method comprising: generating a single-tone signal and an orthogonal signal of the single-tone signal; transmitting the single-tone signal and receiving a reflected signal of the single-tone signal; calculating a propagation delay phase according to the single-tone signal, the orthogonal signal, the reflected signal and a preset sliding integration time; and obtaining a wearing state of the wearable device according to the propagation delay phase. In the present invention, the preset sliding integration time is an integer multiple of a half-cycle of the single-tone signal, so that the propagation delay phase obtained by the sliding correlation integral operation and phase calculation is independent of the amplitude of the reflected signal, and can avoid problems such as detection errors caused by amplitude jitter of the reflected signal in the prior art, thereby improving the accuracy of the wearing state detection of the wearable device; at the same time, a complex receiving front-end amplification circuit is not required, and the single-tone signal width requirement is relatively low.

Description

Technical Field

[0001] The present invention relates to the technical field of smart devices, and in particular to a wearing detection method and system for a wearable device. Background Art

[0002] With the rapid development of wearable devices (such as Bluetooth headsets and smartwatches), detecting the wear status of these devices has become a research hotspot and a key to reducing device power consumption. Currently, ultrasonic detection methods are commonly used to detect the wear status of wearable devices. The detection principle is to transmit ultrasonic waves through a sensor and receive the reflected ultrasonic waves from the body to determine the wear status of the device.

[0003] However, ultrasonic waves propagate in a spherical pattern, resulting in greater energy attenuation the longer they travel. Furthermore, as ultrasonic waves propagate through a medium, some of their energy is absorbed by the air. Furthermore, upon encountering reflective objects, ultrasonic waves undergo reflection, scattering, and diffraction, significantly attenuating the actual reflected ultrasonic waves. Furthermore, due to the influence of thermal noise, variations in the shape and angle of the ultrasonic reflector, as well as changes in the reflection distance, the amplitude of the received ultrasonic waves can vary significantly over time. To improve the accuracy of wearable condition detection and reduce missed detections and false alarms, signal gain control is typically implemented at the receiving front end. Because gain control at the receiving front end requires a settling time, certain requirements are placed on the ultrasonic pulse width. If the pulse width is too narrow, gain control can easily terminate before the adjustment is complete, ultimately leading to detection failure. Therefore, in existing ultrasonic detection methods, the reliability and settling time of gain control at the receiving front end directly impact the accuracy of wearable condition detection.

[0004] Alternatively, a phase-based detection method can be used to detect the wearability of wearable devices. This method can achieve highly accurate phase delay measurement by counting the number of phase zero-crossing changes. However, this method is also affected by the amplitude of the received signal. A weak received signal can affect the phase decision, leading to detection errors. Therefore, phase-based detection methods also rely on the reliability and settling time of the gain control of the receiving front end. Summary of the Invention

[0005] The object of the present invention is to provide a wearing detection method and system for a wearable device, which can calculate the propagation delay phase based on a single-tone signal, an orthogonal signal of the single-tone signal, a reflected signal of the single-tone signal and a preset sliding integration time; by setting the preset sliding integration time to an integer multiple of a half-period of the single-tone signal, the calculated propagation delay phase is independent of the amplitude of the reflected signal, thereby improving the accuracy of wearing status detection of the wearable device.

[0006] In order to achieve the above object, the present invention is implemented through the following technical solutions:

[0007] A wearing detection method for a wearable device, comprising:

[0008] generating a single tone signal and a quadrature signal of the single tone signal;

[0009] transmitting the single tone signal and receiving a reflected signal of the single tone signal;

[0010] Calculating a propagation delay phase according to the single-tone signal, the orthogonal signal, the reflected signal and a preset sliding integration time; and

[0011] The wearing state of the wearable device is obtained according to the propagation delay phase.

[0012] Preferably, the wearing status includes one or any combination of not worn, wearing, worn and removed.

[0013] Preferably, the preset sliding integration time is an integer multiple of a half period of the single tone signal.

[0014] Preferably, the step of calculating the propagation delay phase according to the single tone signal, the orthogonal signal, the reflected signal and a preset sliding integration time includes:

[0015] Performing sliding correlation integration on the single tone signal and the reflected signal according to the preset sliding integration time to obtain a first sliding correlation result;

[0016] Performing sliding correlation integration on the orthogonal signal and the reflected signal according to the preset sliding integration time to obtain a second sliding correlation result; and

[0017] A first propagation delay phase and / or a first correlation amplitude are calculated according to the first sliding correlation result and the second sliding correlation result.

[0018] Preferably, the first sliding correlation result is calculated using the following formula:

[0019]

[0020] Wherein, CORI(T) is the first sliding correlation result; sin(ωt) is the single tone signal, ω is the frequency of the single tone signal, and t is time; A1sin(ωt+θ1) is the reflected signal, A1 is the amplitude of the reflected signal, and θ1 is the propagation delay phase of the reflected signal; T is the preset sliding integration time; τ~τ+T is the integration time period, and τ represents the integration start time;

[0021] The second sliding correlation result is calculated using the following formula:

[0022]

[0023] Wherein, CORQ(T) is the second sliding correlation result; cos(ωt) is the orthogonal signal;

[0024] The first propagation delay phase is calculated using the following formula:

[0025]

[0026] Wherein, θ is the first propagation delay phase;

[0027] The first correlation amplitude is calculated using the following formula:

[0028]

[0029] Wherein, ampt is the first correlation amplitude.

[0030] Preferably, the step of acquiring the wearing state of the wearable device according to the propagation delay phase includes:

[0031] The first propagation delay phases corresponding to adjacent integration time periods change randomly, and the wearable device is in an unworn state;

[0032] The first propagation delay phase corresponding to adjacent integration time periods decreases over time, and the wearable device is in a wearing state;

[0033] The first propagation delay phase corresponding to adjacent integration time periods remains unchanged, and the wearable device is in a worn state; and

[0034] The first propagation delay phase corresponding to adjacent integration time periods increases with time, and the wearable device is in a removal state.

[0035] Preferably, the wearing detection method for a wearable device further includes: obtaining a wearing state of the wearable device according to the first correlation amplitude; and the step of obtaining the wearing state of the wearable device according to the first correlation amplitude includes:

[0036] The first correlation amplitude is less than a first reference threshold, and the wearable device is in an unworn state;

[0037] The first correlation amplitude is greater than a first reference threshold and the first correlation amplitudes corresponding to adjacent integration time periods increase over time, and the wearable device is in a wearing state;

[0038] The first correlation amplitude is greater than a first reference threshold and the first correlation amplitudes corresponding to adjacent integration time periods remain unchanged, and the wearable device is in a worn state; and

[0039] The first correlation amplitude is greater than a first reference threshold and the first correlation amplitudes corresponding to adjacent integration time periods decrease over time, indicating that the wearable device is in a removal state.

[0040] Preferably, when receiving the reflected signal, an attenuated signal of the single-tone signal is also received simultaneously.

[0041] Preferably, the step of calculating the propagation delay phase according to the single tone signal, the orthogonal signal, the reflected signal and a preset sliding integration time includes:

[0042] performing sliding correlation integration on the single tone signal and the reflected signal, and performing sliding correlation integration on the single tone signal and the attenuated signal according to the preset sliding integration time, to obtain a third sliding correlation result;

[0043] performing sliding correlation integration on the orthogonal signal and the reflected signal and performing sliding correlation integration on the orthogonal signal and the attenuated signal according to the preset sliding integration time to obtain a fourth sliding correlation result; and

[0044] A second propagation delay phase and a second correlation amplitude are calculated according to the third sliding correlation result and the fourth sliding correlation result.

[0045] Preferably, the third sliding correlation result is calculated using the following formula:

[0046]

[0047] Wherein, CORI′(T) is the third sliding correlation result; A2sin(ωt+θ2) is the attenuation signal, A2 is the amplitude of the attenuation signal, and θ2 is the propagation delay phase of the attenuation signal;

[0048] The fourth sliding correlation result is calculated using the following formula:

[0049]

[0050] Wherein, CORQ′(T) is the fourth sliding correlation result;

[0051] The second propagation delay phase is calculated using the following formula:

[0052]

[0053] Wherein, θ' is the second propagation delay phase;

[0054] The second correlation amplitude is calculated using the following formula:

[0055]

[0056] Wherein, ampt' is the second correlation amplitude.

[0057] Preferably, the calculating the propagation delay phase according to the single tone signal, the orthogonal signal, the reflected signal and the preset sliding integration time further comprises:

[0058] performing sliding correlation integration on the single tone signal and the attenuated signal according to the preset sliding integration time to obtain a fifth sliding correlation result;

[0059] performing sliding correlation integration on the orthogonal signal and the attenuation signal according to the preset sliding integration time to obtain a sixth sliding correlation result; and

[0060] A reference propagation delay phase and a reference correlation amplitude are calculated according to the fifth sliding correlation result and the sixth sliding correlation result.

[0061] Preferably, the fifth sliding correlation result is calculated using the following formula:

[0062]

[0063] Among them, CORI r (T) is the fifth sliding related result;

[0064] The sixth sliding correlation result is calculated using the following formula:

[0065]

[0066] Among them, CORQ r (T) is the sixth sliding related result;

[0067] The reference propagation delay phase is calculated using the following formula:

[0068]

[0069] Among them, θ r is the reference propagation delay phase;

[0070] The reference correlation amplitude is calculated using the following formula:

[0071]

[0072] Among them, ampt r is the reference correlation amplitude.

[0073] Preferably, the step of acquiring the wearing state of the wearable device according to the propagation delay phase includes:

[0074] When the absolute value of the difference between the second propagation delay phase and the reference propagation delay phase is less than a first preset threshold, and the absolute value of the difference between the second correlation amplitude and the reference correlation amplitude is less than a second preset threshold, the wearable device is in an unworn state;

[0075] When the absolute value of the difference between the second propagation delay phase and the reference propagation delay phase is greater than a first preset threshold, the absolute value of the difference between the second correlation amplitude and the reference correlation amplitude is greater than a second preset threshold, and the second correlation amplitudes corresponding to adjacent integration time periods increase over time, the wearable device is in a worn state;

[0076] The absolute value of the difference between the second propagation delay phase and the reference propagation delay phase is greater than a first preset threshold, the absolute value of the difference between the second correlation amplitude and the reference correlation amplitude is greater than a second preset threshold, and the second correlation amplitudes corresponding to adjacent integration time periods remain unchanged, and the wearable device is in a worn state;

[0077] When the absolute value of the difference between the second propagation delay phase and the reference propagation delay phase is greater than a first preset threshold, the absolute value of the difference between the second correlation amplitude and the reference correlation amplitude is greater than a second preset threshold, and the second correlation amplitude corresponding to adjacent integration time periods decreases over time, the wearable device is in a removal state.

[0078] Based on the same inventive concept, the present invention also provides a wearing detection system for a wearable device, which is used for the wearable device and includes:

[0079] A signal generating module, configured to generate a single tone signal and an orthogonal signal of the single tone signal;

[0080] A signal transmitting module, connected to the signal generating module, for transmitting the single tone signal;

[0081] A signal receiving module, configured to receive a reflected signal of the single tone signal;

[0082] a phase calculation module, connected to the signal receiving module and the signal generating module respectively, for calculating the propagation delay phase according to the single tone signal, the orthogonal signal, the reflected signal and a preset sliding integration time; and

[0083] A detection control module is connected to the phase calculation module and is used to obtain the wearing state of the wearable device according to the propagation delay phase.

[0084] Preferably, the wearing status includes one or any combination of not worn, wearing, worn and removed.

[0085] Preferably, the preset sliding integration time is an integer multiple of a half period of the single tone signal.

[0086] Preferably, the phase calculation module includes:

[0087] a correlation integration unit, connected to the signal receiving module and the signal generating module, respectively, configured to perform sliding correlation integration on the single tone signal and the reflected signal according to the preset sliding integration time to obtain a first sliding correlation result; and perform sliding correlation integration on the orthogonal signal and the reflected signal according to the preset sliding integration time to obtain a second sliding correlation result;

[0088] A phase calculation unit is connected to the correlation integration unit and is used to calculate a first propagation delay phase and / or a first correlation amplitude according to the first sliding correlation result and the second sliding correlation result.

[0089] Preferably, the first sliding correlation result is calculated using the following formula:

[0090]

[0091] Wherein, CORI(T) is the first sliding correlation result; sin(ωt) is the single tone signal, ω is the frequency of the single tone signal, and t is time; A1sin(ωt+θ1) is the reflected signal, A1 is the amplitude of the reflected signal, and θ1 is the propagation delay phase of the reflected signal; T is the preset sliding integration time; τ~τ+T is the integration time period, and τ represents the integration start time;

[0092] The second sliding correlation result is calculated using the following formula:

[0093]

[0094] Wherein, CORQ(T) is the second sliding correlation result; cos(ωt) is the orthogonal signal;

[0095] The first propagation delay phase is calculated using the following formula:

[0096]

[0097] Wherein, θ is the first propagation delay phase;

[0098] The first correlation amplitude is calculated using the following formula:

[0099]

[0100] Wherein, ampt is the first correlation amplitude.

[0101] Preferably, the detection control module includes a comparison unit connected to the phase calculation unit, configured to compare the first propagation delay phase and / or the first correlation amplitude of adjacent integration time periods to obtain the wearing state of the wearable device.

[0102] Preferably, the first propagation delay phases corresponding to adjacent integration time periods vary randomly, and the wearable device is in an unworn state;

[0103] The first propagation delay phase corresponding to adjacent integration time periods decreases over time, and the wearable device is in a wearing state;

[0104] The first propagation delay phase corresponding to adjacent integration time periods remains unchanged, and the wearable device is in a worn state; and

[0105] The first propagation delay phase corresponding to adjacent integration time periods increases with time, and the wearable device is in a removal state.

[0106] Preferably, the first correlation amplitude is smaller than a first reference threshold, and the wearable device is in an unworn state;

[0107] The first correlation amplitude is greater than a first reference threshold and the first correlation amplitudes corresponding to adjacent integration time periods increase over time, and the wearable device is in a wearing state;

[0108] The first correlation amplitude is greater than a first reference threshold and the first correlation amplitudes corresponding to adjacent integration time periods remain unchanged, and the wearable device is in a worn state; and

[0109] The first correlation amplitude is greater than a first reference threshold and the first correlation amplitudes corresponding to adjacent integration time periods decrease over time, indicating that the wearable device is in a removal state.

[0110] Preferably, when the signal receiving module receives the reflected signal, it also receives the attenuated signal of the single tone signal.

[0111] Preferably, the correlation integration unit is further configured to perform sliding correlation integration on the single tone signal and the reflected signal and perform sliding correlation integration on the single tone signal and the attenuated signal according to the preset sliding integration time to obtain a third sliding correlation result; and

[0112] performing sliding correlation integration on the orthogonal signal and the reflected signal, and performing sliding correlation integration on the orthogonal signal and the attenuated signal according to the preset sliding integration time, to obtain a fourth sliding correlation result;

[0113] The phase calculation unit is further configured to calculate a second propagation delay phase and a second correlation amplitude according to the third sliding correlation result and the fourth sliding correlation result.

[0114] Preferably, the third sliding correlation result is calculated using the following formula:

[0115]

[0116] Wherein, CORI′(T) is the third sliding correlation result; A2sin(ωt+θ2) is the attenuation signal, A2 is the amplitude of the attenuation signal, and θ2 is the propagation delay phase of the attenuation signal;

[0117] The fourth sliding correlation result is calculated using the following formula:

[0118]

[0119] Wherein, CORQ′(T) is the fourth sliding correlation result;

[0120] The second propagation delay phase is calculated using the following formula:

[0121]

[0122] Wherein, θ' is the second propagation delay phase;

[0123] The second correlation amplitude is calculated using the following formula:

[0124]

[0125] Wherein, ampt' is the second correlation amplitude.

[0126] Preferably, the correlation integration unit is further configured to perform sliding correlation integration on the single tone signal and the attenuated signal according to the preset sliding integration time to obtain a fifth sliding correlation result; and

[0127] performing sliding correlation integration on the orthogonal signal and the attenuation signal according to the preset sliding integration time to obtain a sixth sliding correlation result;

[0128] The phase calculation unit is further configured to calculate a reference propagation delay phase and a reference correlation amplitude according to the fifth sliding correlation result and the sixth sliding correlation result.

[0129] Preferably, the fifth sliding correlation result is calculated using the following formula:

[0130]

[0131] Among them, CORIr (T) is the fifth sliding related result;

[0132] The sixth sliding correlation result is calculated using the following formula:

[0133]

[0134] Among them, CORQ r (T) is the sixth sliding related result;

[0135] The reference propagation delay phase is calculated using the following formula:

[0136]

[0137] Among them, θ r is the reference propagation delay phase;

[0138] The reference correlation amplitude is calculated using the following formula:

[0139]

[0140] Among them, ampt r is the reference correlation amplitude.

[0141] Preferably, the comparison unit is further configured to compare the second propagation delay phase with the reference propagation delay phase and compare the second correlation amplitude with the reference correlation amplitude to obtain the wearing state of the wearable device.

[0142] Preferably, when the absolute value of the difference between the second propagation delay phase and the reference propagation delay phase is less than a first preset threshold, and the absolute value of the difference between the second correlation amplitude and the reference correlation amplitude is less than a second preset threshold, the wearable device is in an unworn state;

[0143] When the absolute value of the difference between the second propagation delay phase and the reference propagation delay phase is greater than a first preset threshold, the absolute value of the difference between the second correlation amplitude and the reference correlation amplitude is greater than a second preset threshold, and the second correlation amplitudes corresponding to adjacent integration time periods increase over time, the wearable device is in a worn state;

[0144] The absolute value of the difference between the second propagation delay phase and the reference propagation delay phase is greater than a first preset threshold, the absolute value of the difference between the second correlation amplitude and the reference correlation amplitude is greater than a second preset threshold, and the second correlation amplitudes corresponding to adjacent integration time periods remain unchanged, and the wearable device is in a worn state;

[0145] When the absolute value of the difference between the second propagation delay phase and the reference propagation delay phase is greater than a first preset threshold, the absolute value of the difference between the second correlation amplitude and the reference correlation amplitude is greater than a second preset threshold, and the second correlation amplitude corresponding to adjacent integration time periods decreases over time, the wearable device is in a removal state.

[0146] Preferably, the detection control module further includes: a control unit connected to the comparison unit, configured to switch an operating mode of the wearable device according to a wearing state of the wearable device.

[0147] Compared with the prior art, the present invention has at least one of the following advantages:

[0148] The present invention provides a wearing detection method and system for a wearable device, which can generate a single-tone signal and its orthogonal signal, and receive a reflected signal after the single-tone signal is transmitted, so as to calculate the propagation delay phase according to the single-tone signal, the orthogonal signal, the reflected signal and a preset sliding integration time, thereby obtaining the wearing status of the wearable device according to the propagation delay phase.

[0149] The present invention presets the sliding integration time as an integer multiple of the half-cycle of the single-tone signal, so that the propagation delay phase obtained by the sliding correlation integral operation and phase calculation is independent of the amplitude of the reflected signal, which can avoid the detection error and other problems caused by the jitter of the reflected signal amplitude in the prior art, thereby improving the accuracy of the wearing status detection of the wearable device; at the same time, it does not require a complex receiving front-end amplification circuit, and has a low requirement for the width of the single-tone signal.

[0150] The setting of the integration time period in the present invention reduces the amount of data that needs to be cached during the sliding correlation integral operation and phase calculation, reduces the requirements for computing resources and storage resources, and reduces the processing delay.

[0151] The present invention can be applied to the situation where the reflected signal and the attenuated signal are received at different times, and can also be applied to the situation where the reflected signal and the attenuated signal are received at the same time, and has good applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0152] Figure 1 This is a flowchart of a wearing detection method for a wearable device provided by one embodiment of the present invention;

[0153] Figure 2 The present invention is a structural diagram of a wear detection system for a wearable device provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0154] The following is a further detailed description of a wearing detection method and system for a wearable device proposed by the present invention in conjunction with the accompanying drawings and specific embodiments. According to the following description, the advantages and features of the present invention will become clearer. It should be noted that the drawings are in a very simplified form and use non-precise proportions, which are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention. In order to make the purposes, features and advantages of the present invention more obvious and easy to understand, please refer to the accompanying drawings. It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the implementation conditions of the present invention. Therefore, they have no technical significance. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed by the present invention without affecting the efficacy and purpose that can be achieved by the present invention.

[0155] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply the existence of any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0156] Combined with attachment Figure 1 As shown, this embodiment provides a wearing detection method for a wearable device, including: step S110, generating a single-tone signal and an orthogonal signal of the single-tone signal; step S120, transmitting the single-tone signal, and receiving a reflected signal of the single-tone signal; step S130, calculating a propagation delay phase according to the single-tone signal, the orthogonal signal, the reflected signal, and a preset sliding integration time; and step S140, obtaining a wearing state of the wearable device according to the propagation delay phase, and the wearing state includes one or any combination of not worn, wearing, worn, and removed.

[0157] Specifically, in this embodiment, in step S110, the single-tone signal may be ultrasonic, and the frequency of the single-tone signal may be 40 kHz to 120 kHz. After the single-tone signal is generated, a quadrature signal of the single-tone signal may be generated by performing phase rotation on the single-tone signal or using a lookup table. In other embodiments, the frequency of the single-tone signal may be within the human hearing range or greater than the frequency of ultrasonic waves, but the present invention is not limited thereto.

[0158] Specifically, in this embodiment, in the step S120, after the single-tone signal is transmitted in the form of a pulse as a transmitting signal, the ultrasonic wave reflected back by the reflecting surface is the reflected signal. More specifically, not only the reflected signal will be received, but the transmitting signal will also be received after passing through a certain path; since the received transmitting signal has a path propagation delay and attenuation, the received transmitting signal is not the same as the generated single-tone signal, and the received transmitting signal can be recorded as the attenuated signal of the single-tone signal; at the same time, the signal reception situation can also be divided into two types: the first situation is that the transmitting signal and the attenuated signal are not received at the same time, that is, time-sharing reception; the second situation is that the transmitting signal and the attenuated signal are received at the same time. For different signal reception situations, different formulas can be used in the step S130 to calculate the propagation delay phase to ensure the detection accuracy of the wearing status of the wearable device, but the present invention is not limited to this.

[0159] Please continue to refer to Figure 1 , the signal reception situation is the first situation, that is, when the transmitted signal and the attenuated signal are received in time-sharing mode, the step S130 includes: performing sliding correlation integration on the single-tone signal and the reflected signal according to the preset sliding integration time to obtain a first sliding correlation result; performing sliding correlation integration on the orthogonal signal and the reflected signal according to the preset sliding integration time to obtain a second sliding correlation result; and calculating a first propagation delay phase according to the first sliding correlation result and the second sliding correlation result.

[0160] It is understandable that, in some other embodiments, the first sliding-related result is calculated using the following formula:

[0161]

[0162] Wherein, CORI(T) is the first sliding correlation result; sin(ωt) is the single tone signal, ω is the frequency of the single tone signal, and t is time; A1sin(ωt+θ1) is the reflected signal, A1 is the amplitude of the reflected signal, and θ1 is the propagation delay phase of the reflected signal; T is the preset sliding integration time; τ~τ+T is the integration time period, and τ represents the integration start time;

[0163] The second sliding correlation result is calculated using the following formula:

[0164]

[0165] Wherein, CORQ(T) is the second sliding correlation result; cos(ωt) is the orthogonal signal;

[0166] The first propagation delay phase is calculated using the following formula:

[0167]

[0168] Wherein, θ is the first propagation delay phase.

[0169] In some embodiments, the preset sliding integration time is an integer multiple of a half period of the single tone signal.

[0170] Specifically, in this embodiment, formula (1) is expanded to obtain

[0171]

[0172] After expanding formula (2), we can get

[0173]

[0174] Since the preset sliding integration time T is an integer multiple of the half period of the single tone signal, only the first term remains in formulas (4) and (5), namely:

[0175] CORI(T)=A1Tcos(θ1) / 2 (6)

[0176] CORQ(T)=A1Tsin(θ1) / 2 (7)

[0177] From formula (6) and formula (7), we can deduce

[0178]

[0179] Since the transmission signal and the attenuated signal are received in time-sharing mode, the first propagation delay phase θ calculated at this time is the propagation delay phase θ1 of the reflected signal, and formula (3) can be obtained from formula (8). More specifically, since the single-tone signal, the orthogonal signal, the reflected signal and the preset sliding integration time are all known, the first sliding integration result and the second sliding integration result can be obtained according to formulas (1) and (2); the first sliding integration result and the second sliding integration result are substituted into formula (3) to obtain the first propagation delay phase θ. In addition, when the transmission signal and the attenuated signal are received in time-sharing mode, it can be seen from formula (3) that the calculation of the first propagation delay phase θ does not involve the amplitude of the reflected signal, so that the subsequent detection of the wearing state of the wearable device does not depend on the amplitude of the reflected signal, thereby improving the detection accuracy of the wearing state of the wearable device, but the present invention is not limited to this.

[0180] Specifically, in this embodiment, the preset sliding integration time T is generally in the order of milliseconds. Then, within the integration time period τ~τ+T, the relative position of the emission point of the single-tone signal and the reflecting surface remains fixed. At this time, the amplitude A1 and the propagation delay phase θ1 of the reflected signal are short-term stable. Therefore, the amplitude A1 and the propagation delay phase θ1 of the reflected signal can be regarded as constant values ​​within the integration time period τ~τ+T, but the present invention is not limited to this.

[0181] Please continue to refer to Figure 1 , the step S140 includes: the first propagation delay phase corresponding to adjacent integration time periods changes randomly, and the wearable device is in an unworn state; the first propagation delay phase corresponding to adjacent integration time periods decreases over time, and the wearable device is in a worn state; the first propagation delay phase corresponding to adjacent integration time periods remains unchanged, and the wearable device is in a worn state; and the first propagation delay phase corresponding to adjacent integration time periods increases over time, and the wearable device is in a removed state.

[0182] Specifically, in this embodiment, by comparing the change in the first propagation delay phase corresponding to the current integration time period (e.g., τ1 to τ1+T) and the change in the first propagation delay phase corresponding to the previous integration time period (e.g., τ0 to τ0+T and τ0+T ≤ τ1), that is, the change in the first propagation delay phase corresponding to adjacent integration time periods, the wearing state of the wearable device can be determined. More specifically, if the first propagation delay phase corresponding to the current integration time period and the first propagation delay phase corresponding to the previous integration time period both change randomly, the wearable device is in an unworn state; if the first propagation delay phase corresponding to the current integration time period is less than the first propagation delay phase corresponding to the previous integration time period, the wearable device is in a worn state; if the first propagation delay phase corresponding to the current integration time period is the same as the first propagation delay phase corresponding to the previous integration time period, the wearable device is in a worn state; if the first propagation delay phase corresponding to the current integration time period is greater than the first propagation delay phase corresponding to the previous integration time period, the wearable device is in a removed state, but the present invention is not limited to this.

[0183] Please continue to refer to Figure 1 The wearing detection method for the wearable device further includes: calculating a first correlation amplitude according to the first sliding integral result and the second sliding integral result; and obtaining a wearing state of the wearable device according to the first correlation amplitude;

[0184] It is understandable that, in some other embodiments, the first correlation amplitude ampt is calculated using the following formula:

[0185]

[0186] In some embodiments, the step of obtaining the wearing status of the wearable device according to the first correlation amplitude includes: the first correlation amplitude is less than the first reference threshold, and the wearable device is in an unworn state; the first correlation amplitude is greater than the first reference threshold and the first correlation amplitude corresponding to adjacent integration time periods increases with time, and the wearable device is in a worn state; the first correlation amplitude is greater than the first reference threshold and the correlation amplitude corresponding to adjacent integration time periods remains unchanged, and the wearable device is in a worn state; and the first correlation amplitude is greater than the first reference threshold and the first correlation amplitude corresponding to adjacent integration time periods decreases with time, and the wearable device is in a removed state.

[0187] Specifically, in this embodiment, the first reference threshold value can be the average value of the first correlation amplitudes calculated when the wearable device is subjected to multiple non-wearing experiments under an ideal laboratory environment. Under the premise that the first correlation amplitude corresponding to the current integration time period (for example, τ1~τ1+T) is greater than the first reference threshold value, if the first correlation amplitude corresponding to the current integration time period is greater than the first correlation amplitude corresponding to the previous integration time period (for example, τ0~τ0+T and τ0+T≤τ1), the wearable device is in the wearing state; if the first correlation amplitude corresponding to the current integration time period is the same as the first correlation amplitude corresponding to the previous integration time period, the wearable device is in the worn state; if the first correlation amplitude corresponding to the current integration time period is less than the first correlation amplitude corresponding to the previous integration time period, the wearable device is in the removal state, but the present invention is not limited to this.

[0188] In addition, in this embodiment, the wearing state of the wearable device can also be determined based on the first correlation amplitude and the first propagation delay phase to further improve the detection accuracy of the wearing state of the wearable device. Specifically, when the first propagation delay phase corresponding to the current integration time period (e.g., τ1 to τ1+T) and the first propagation delay phase corresponding to the previous integration time period (e.g., τ0 to τ0+T and τ0+T ≤ τ1) vary randomly, and the first correlation amplitude corresponding to the current integration time period is less than a second reference threshold, the wearable device is in an unworn state; when the first propagation delay phase corresponding to the current integration time period is less than the first propagation delay phase corresponding to the previous integration time period, and the first correlation amplitude corresponding to the current integration time period is greater than the second reference threshold, the wearable device is in a worn state; when the first propagation delay phase corresponding to the current integration time period is the same as the first propagation delay phase corresponding to the previous integration time period, and the first correlation amplitude corresponding to the current integration time period is greater than a third reference threshold, the wearable device is in a worn state; when the first propagation delay phase corresponding to the current integration time period is greater than the first propagation delay phase corresponding to the previous integration time period, and the first correlation amplitude corresponding to the current integration time period is less than the third reference threshold, the wearable device is in a removed state. Preferably, the second reference threshold may be the average value of the first correlation amplitude calculated when the wearable device is worn multiple times in an ideal laboratory environment, and the third reference threshold may be the average value of the first correlation amplitude calculated when the wearable device is worn multiple times in an ideal laboratory environment, but the present invention is not limited thereto.

[0189] Please continue to refer to Figure 1, when receiving the reflected signal, the attenuated signal of the single-tone signal is simultaneously received, that is, when the signal reception situation is the second situation, the step S130 includes: performing sliding correlation integration on the single-tone signal and the reflected signal, and performing sliding correlation integration on the single-tone signal and the attenuated signal according to the preset sliding integration time to obtain a third sliding correlation result; performing sliding correlation integration on the orthogonal signal and the reflected signal, and performing sliding correlation integration on the orthogonal signal and the attenuated signal according to the preset sliding integration time to obtain a fourth sliding correlation result; and calculating a second propagation delay phase and a second correlation amplitude based on the third sliding correlation result and the fourth sliding correlation result.

[0190] It is understandable that, in some other embodiments, the third sliding correlation result is calculated using the following formula:

[0191]

[0192] Wherein, CORI′(T) is the third sliding correlation result; A2sin(ωt+θ2) is the attenuation signal, A2 is the amplitude of the attenuation signal, and θ2 is the propagation delay phase of the attenuation signal;

[0193] The fourth sliding correlation result is calculated using the following formula:

[0194]

[0195] Wherein, CORQ′(T) is the fourth sliding correlation result;

[0196] The second propagation delay phase is calculated using the following formula:

[0197]

[0198] Wherein, θ' is the second propagation delay phase;

[0199] The second correlation amplitude is calculated using the following formula:

[0200]

[0201] Wherein, ampt' is the second correlation amplitude.

[0202] Specifically, in this embodiment, since the relative positions of the transmitting point and the receiving point of the single-tone signal remain fixed, within the integration time period τ~τ+T, the amplitude A2 and the propagation delay phase θ2 of the attenuated signal are stable, that is, both are constant values, but the present invention is not limited to this.

[0203] Please continue to refer to Figure 1, the step S130 further includes: performing a sliding correlation integration on the single-tone signal and the attenuated signal according to the preset sliding integration time to obtain a fifth sliding correlation result; performing a sliding correlation integration on the orthogonal signal and the attenuated signal according to the preset sliding integration time to obtain a sixth sliding correlation result; and calculating a reference propagation delay phase and a reference correlation amplitude based on the fifth sliding correlation result and the sixth sliding correlation result.

[0204] It is understandable that, in some other embodiments, the fifth sliding correlation result is calculated using the following formula:

[0205]

[0206] Among them, CORI r (T) is the fifth sliding related result;

[0207] The sixth sliding correlation result is calculated using the following formula:

[0208]

[0209] Among them, CORQ r (T) is the sixth sliding related result;

[0210] The reference propagation delay phase is calculated using the following formula:

[0211]

[0212] Among them, θ r is the reference propagation delay phase;

[0213] The reference correlation amplitude is calculated using the following formula:

[0214]

[0215] Among them, ampt r is the reference correlation amplitude.

[0216] Specifically, in this embodiment, since the preset sliding integration time T is an integer multiple of the half period of the single tone signal, the formula (10) can be expanded to obtain

[0217] CORI′(T)=A1Tcos(θ1) / 2+A2Tcos(θ2) / 2 (18)

[0218] After expanding formula (11), we can get

[0219] CORQ′(T)=A1Tsin(θ1) / 2+A2Tsin(θ2) / 2 (19)

[0220] Formula (12) can then be transformed into

[0221]

[0222] It can be seen from formula (20) that when the transmitted signal and the attenuated signal are received simultaneously, the calculated second propagation delay phase θ' involves both the propagation delay phase θ1 of the reflected signal and the propagation delay phase θ2 of the attenuated signal. At this time, the wearing status of the wearable device cannot be determined based solely on the change in the second propagation delay phase.

[0223] Specifically, from formulas (14), (15) and (16), it can be seen that the reference propagation delay phase θ r That is, the propagation delay phase θ2 of the attenuated signal when there is no reflected signal; combined with formula (20), it can be seen that when the reflected signal and the attenuated signal exist at the same time, the calculated second propagation delay θ' is equal to the reference propagation delay phase θ r There is a certain deviation, and the second correlation amplitude ampt' calculated similarly is different from the reference correlation amplitude ampt r There is also a certain deviation. Since the attenuation signal remains unchanged, the stronger the reflected signal is (that is, the larger the amplitude A1 and propagation delay phase θ1 of the reflected signal are), the greater the deviation between the calculated second propagation delay and the reference propagation delay phase, and similarly, the greater the deviation between the calculated second correlation amplitude and the reference correlation amplitude. Therefore, the wearing state of the wearable device can be judged based on the difference between the second propagation delay and the reference propagation delay phase and the difference between the second correlation amplitude and the reference correlation amplitude, but the present invention is not limited to this.

[0224] More specifically, in this embodiment, since the single-tone signal, the orthogonal signal, the reflected signal, the attenuated signal and the preset sliding integration time are all known, the third sliding integration result, the fourth sliding integration result, the fifth sliding integration result and the sixth sliding integration result can be obtained respectively according to formulas (10), (11), (14) and (15); the third sliding integration result and the fourth sliding integration result are substituted into formulas (12) and (13) to obtain the second propagation delay phase and the second correlation amplitude respectively; the fifth sliding integration result and the sixth sliding integration result are substituted into formulas (16) and (17) to obtain the reference propagation delay phase and the reference correlation amplitude respectively. Preferably, the reference propagation delay phase and the reference correlation amplitude can be calculated under an ideal laboratory environment.

[0225] Please continue to refer to Figure 1 Step S140 includes: when the absolute value of the difference between the second propagation delay phase and the reference propagation delay phase is less than a first preset threshold, and the absolute value of the difference between the second correlation amplitude and the reference correlation amplitude is less than a second preset threshold, the wearable device is in an unworn state; when the absolute value of the difference between the second propagation delay phase and the reference propagation delay phase is greater than the first preset threshold, the absolute value of the difference between the second correlation amplitude and the reference correlation amplitude is greater than a second preset threshold, and the second correlation amplitudes corresponding to adjacent integration time periods increase over time, the wearable device is in a worn state; when the absolute value of the difference between the second propagation delay phase and the reference propagation delay phase is greater than the first preset threshold, the absolute value of the difference between the second correlation amplitude and the reference correlation amplitude is greater than the second preset threshold, and the second correlation amplitudes corresponding to adjacent integration time periods remain unchanged, the wearable device is in a worn state; when the absolute value of the difference between the second propagation delay phase and the reference propagation delay phase is greater than the first preset threshold, the absolute value of the difference between the second correlation amplitude and the reference correlation amplitude is greater than the second preset threshold, and the second correlation amplitudes corresponding to adjacent integration time periods decrease over time, the wearable device is in a removed state.

[0226] Specifically, in this embodiment, the first preset threshold value can be the absolute maximum value, absolute average value or root mean square value of the difference between the second propagation delay phase and the reference propagation delay phase calculated when the wearable device is not worn for multiple times under an ideal laboratory environment; the second preset threshold value can be the absolute maximum value, absolute average value or root mean square value of the difference between the second correlation amplitude and the reference correlation amplitude calculated when the wearable device is not worn for multiple times under an ideal laboratory environment.

[0227] More specifically, under the premise that the absolute value of the difference between the second propagation delay phase corresponding to the current integration time period (for example, τ1~τ1+T) and the reference propagation delay phase is greater than the first preset threshold, and the absolute value of the difference between the second correlation amplitude corresponding to the current integration time period (for example, τ1~τ1+T) and the reference correlation amplitude is greater than the second preset threshold, if the second correlation amplitude corresponding to the current integration time period (for example, τ1~τ1+T) is greater than the second correlation amplitude corresponding to the previous integration time period (for example, τ0~τ0+T and τ0+T≤τ1), that is, the second correlation amplitude corresponding to the adjacent integration time period increases over time, then the wearable device is in the wearing state; if the second correlation amplitude corresponding to the current integration time period is the same as the second correlation amplitude corresponding to the previous integration time period, that is, the second correlation amplitude corresponding to the adjacent integration time period remains unchanged, then the wearable device is in the worn state; if the second correlation amplitude corresponding to the current integration time period is less than the second correlation amplitude corresponding to the previous integration time period, that is, the second correlation amplitude corresponding to the adjacent integration time period decreases over time, then the wearable device is in the removal state, but the present invention is not limited to this.

[0228] In this embodiment, a propagation delay phase change curve can also be fitted based on the propagation delay phase data corresponding to adjacent integration time periods to obtain the curvature of the corresponding propagation delay phase change. In addition, the setting of the integration time period τ to τ + T can change the existing technology from requiring the calculation of N multiplication and accumulation results (N is the number of sampling points included in the sampling time interval) for one sampling time interval to only requiring one multiplication and accumulation calculation, greatly saving computing logic resources. At the same time, due to the time-sharing processing between the current integration time period and its previous and next integration time periods, it is no longer necessary to cache the data of all integration time periods, which can reduce storage resources. In addition, in this embodiment, the output of one phase result for each sampling point in the existing technology is changed to outputting one propagation delay phase for each integration time period; although outputting one phase result for each sampling point appears to be more accurate and more real-time, the two phase results output by adjacent sampling points are highly correlated, so the changes will not be large. In order to see the phase changes of the related results, a longer time interval is required. In this embodiment, the current integration time period is adjacent to but does not overlap with the previous integration time period and the next integration time period. Thus, there is a longer time interval between adjacent integration time periods, so that the two adjacent propagation delay phases calculated have better distinction, but the present invention is not limited to this.

[0229] Based on the same inventive concept, combined with the attached Figure 2As shown, this embodiment also provides a wearing detection system for a wearable device, which is used for a wearable device, including: a signal generating module 201, which is used to generate a single-tone signal and an orthogonal signal of the single-tone signal; a signal transmitting module 202, which is connected to the signal generating module 201, and is used to transmit the single-tone signal; a signal receiving module 203, which is used to receive the reflected signal of the single-tone signal; a phase calculation module 204, which is respectively connected to the signal receiving module 203 and the signal generating module 201, and is used to calculate the propagation delay phase according to the single-tone signal, the orthogonal signal, the reflected signal and the preset sliding integration time; and a detection control module 205, which is connected to the phase calculation module 204, and is used to obtain the wearing state of the wearable device according to the propagation delay phase; and the wearing state includes one or any combination of not wearing, wearing, worn and removed.

[0230] Specifically, in this embodiment, a digital-to-analog converter (DAC) 206 is further provided between the signal generating module 201 and the signal transmitting module 202 for converting the digital signal format of the monophonic signal into an analog signal format. An analog-to-digital converter (ADC) 207 is further provided between the signal receiving module 203 and the phase calculation module 204, and the signal receiving module 203 can convert the acoustic signal format of the reflected signal into an analog signal format through the analog circuit at its front end, and then convert it into a digital signal format through the analog-to-digital converter (ADC) 207 and transmit it to the phase calculation module 204. Preferably, a filter 208 is further provided between the analog-to-digital converter (ADC) 207 and the phase calculation module 204 to filter out interference such as low-frequency noise and human voice in the reflected signal. Preferably, different ultrasonic sensors can be used as the signal transmitting module 202 and the signal receiving module 203 respectively; in some embodiments, the speaker in the wearable device can also be used as the signal transmitting module 202, and the microphone in the wearable device can be used as the signal receiving module 203, but the present invention is not limited to this.

[0231] Specifically, in this embodiment, the signal transmitting module 202 and the signal receiving module 203 can operate either in a time-sharing manner or simultaneously. When the signal transmitting module 202 and the signal receiving module 203 operate in a time-sharing manner, the signal receiving module 203 will not receive the reflected signal and the attenuated signal simultaneously. When the signal transmitting module 202 and the signal receiving module 203 operate simultaneously, the signal receiving module 203 will receive the reflected signal and the attenuated signal simultaneously. More specifically, when the signal transmitting module 202 and the signal receiving module 203 operate in a time-sharing manner, the analog circuitry at the front end of the signal receiving module 202 can be time-shared, simplifying the circuitry but increasing the complexity of timing control. When the signal transmitting module 202 and the signal receiving module 203 operate simultaneously, the analog circuitry at the front end of the signal receiving module 202 for receiving the reflected signal and the analog circuitry for receiving the attenuated signal must be separated, increasing the complexity of the circuitry but increasing the simplicity of timing control.

[0232] Please continue to refer to Figure 2 The phase calculation module 204 includes: a correlation integration unit 2041, connected to the signal receiving module 203 and the signal generating module 201, respectively; and a phase calculation unit 2042, connected to the correlation integration unit 2041. When the signal transmitting module 202 and the signal receiving module 203 work in a time-sharing manner, that is, when the signal receiving module 203 does not receive the reflected signal and the attenuated signal at the same time, the correlation integration unit 2041 is configured to perform a sliding correlation integration on the single-tone signal and the reflected signal according to the preset sliding integration time to obtain a first sliding correlation result; and perform a sliding correlation integration on the orthogonal signal and the reflected signal according to the preset sliding integration time to obtain a second sliding correlation result; and the phase calculation unit 2041 is configured to calculate a first propagation delay phase and / or a first correlation amplitude based on the first sliding correlation result and the second sliding correlation result.

[0233] It is understandable that, in some other embodiments, the first sliding-related result is calculated using the following formula:

[0234]

[0235] Wherein, CORI(T) is the first sliding correlation result; sin(ωt) is the single-tone signal, ω is the frequency of the single-tone signal, and t is time; A1sin(ωt+θ1) is the reflected signal, A1 is the amplitude of the reflected signal, and θ1 is the propagation delay phase of the reflected signal; T is the preset sliding integration time, and the preset sliding integration time is an integer multiple of the half-cycle of the single-tone signal; τ~τ+T is the integration time period, and τ represents the starting time of integration;

[0236] The second sliding correlation result is calculated using the following formula:

[0237]

[0238] Wherein, CORQ(T) is the second sliding correlation result; cos(ωt) is the orthogonal signal;

[0239] The first propagation delay phase is calculated using the following formula:

[0240]

[0241] Wherein, θ is the first propagation delay phase;

[0242] The first correlation amplitude is calculated using the following formula:

[0243]

[0244] Wherein, ampt is the first correlation amplitude.

[0245] Please continue to refer to Figure 2 The detection control module 205 includes: a comparison unit 2051, connected to the phase calculation unit 2042, for comparing the first propagation delay phase and / or the first correlation amplitude of adjacent integration time periods to obtain the wearing status of the wearable device.

[0246] It can be understood that, in some other embodiments, when the comparison unit 2051 determines the wearing state of the wearable device only by comparing the changes in the first propagation delay phase of adjacent integration time periods, if the first propagation delay phase corresponding to adjacent integration time periods changes randomly, the wearable device is in an unworn state; the first propagation delay phase corresponding to adjacent integration time periods decreases over time, and the wearable device is in a worn state; the first propagation delay phase corresponding to adjacent integration time periods remains unchanged, and the wearable device is in a worn state; and the first propagation delay phase corresponding to adjacent integration time periods increases over time, and the wearable device is in a removed state.

[0247] In some embodiments, when the comparison unit 2051 judges the wearing status of the wearable device only by comparing the changes in the first correlation amplitudes of adjacent integration time periods, if the first correlation amplitude is less than the first reference threshold, the wearable device is in an unworn state; if the first correlation amplitude is greater than the first reference threshold and the first correlation amplitude corresponding to the adjacent integration time periods increases with time, the wearable device is in a worn state; if the first correlation amplitude is greater than the first reference threshold and the first correlation amplitude corresponding to the adjacent integration time periods remains unchanged, the wearable device is in a worn state; and if the first correlation amplitude is greater than the first reference threshold and the first correlation amplitude corresponding to the adjacent integration time periods decreases with time, the wearable device is in a removed state.

[0248] In some embodiments, the comparison unit 2051 may further determine the wearing state of the wearable device based on the first correlation amplitude and the first propagation delay phase, so as to further improve the detection accuracy of the wearing state of the wearable device. Specifically, when the first propagation delay phase corresponding to the current integration time period (for example, τ1~τ1+T) and the first propagation delay phase corresponding to the previous integration time period (for example, τ0~τ0+T and τ0+T≤τ1) randomly change, and the first correlation amplitude corresponding to the current integration time period is less than the second reference threshold, the wearable device is in the unworn state; when the first propagation delay phase corresponding to the current integration time period is less than the first propagation delay phase corresponding to the previous integration time period, and the first correlation amplitude corresponding to the current integration time period is greater than the second reference threshold, the wearable device is in the worn state; when the first propagation delay phase corresponding to the current integration time period is the same as the first propagation delay phase corresponding to the previous integration time period, and the first correlation amplitude corresponding to the current integration time period is greater than the third reference threshold, the wearable device is in the worn state; when the first propagation delay phase corresponding to the current integration time period is greater than the first propagation delay phase corresponding to the previous integration time period, and the first correlation amplitude corresponding to the current integration time period is less than the third reference threshold, the wearable device is in the removed state.

[0249] Please continue to refer to Figure 2When the signal receiving module 203 receives the reflected signal, it also receives the attenuated signal of the single-tone signal. That is, when the signal transmitting module 202 and the signal receiving module 203 work simultaneously, the correlation integration unit 2041 is used to perform sliding correlation integration on the single-tone signal and the reflected signal, and to perform sliding correlation integration on the single-tone signal and the attenuated signal according to the preset sliding integration time, so as to obtain a third sliding correlation result; and to perform sliding correlation integration on the orthogonal signal and the reflected signal, and to perform sliding correlation integration on the orthogonal signal and the attenuated signal according to the preset sliding integration time, so as to obtain a fourth sliding correlation result; the phase calculation unit 2042 is used to calculate the second propagation delay phase and the second correlation amplitude according to the third sliding correlation result and the fourth sliding correlation result.

[0250] In some embodiments, the third sliding correlation result is calculated using the following formula:

[0251]

[0252] Wherein, CORI′(T) is the third sliding correlation result; A2sin(ωt+θ2) is the attenuation signal, A2 is the amplitude of the attenuation signal, and θ2 is the propagation delay phase of the attenuation signal;

[0253] The fourth sliding correlation result is calculated using the following formula:

[0254]

[0255] Wherein, CORQ′(T) is the fourth sliding correlation result;

[0256] The second propagation delay phase is calculated using the following formula:

[0257]

[0258] Wherein, θ' is the second propagation delay phase;

[0259] The second correlation amplitude is calculated using the following formula:

[0260]

[0261] Wherein, ampt' is the second correlation amplitude.

[0262] Please continue to refer to Figure 2When the signal transmitting module 202 and the signal receiving module 203 work simultaneously, the correlation integration unit 2041 is further used to perform sliding correlation integration on the single-tone signal and the attenuated signal according to the preset sliding integration time to obtain a fifth sliding correlation result; and perform sliding correlation integration on the orthogonal signal and the attenuated signal according to the preset sliding integration time to obtain a sixth sliding correlation result; the phase calculation unit 2042 is further used to calculate a reference propagation delay phase and a reference correlation amplitude based on the fifth sliding correlation result and the sixth sliding correlation result.

[0263] It is understandable that, in some other embodiments, the fifth sliding correlation result is calculated using the following formula:

[0264]

[0265] Among them, CORI r (T) is the fifth sliding related result;

[0266] The sixth sliding correlation result is calculated using the following formula:

[0267]

[0268] Among them, CORQ r (T) is the sixth sliding related result;

[0269] The reference propagation delay phase is calculated using the following formula:

[0270]

[0271] Among them, θ r is the reference propagation delay phase;

[0272] The reference correlation amplitude is calculated using the following formula:

[0273]

[0274] Among them, ampt r is the reference correlation amplitude.

[0275] Please continue to refer to Figure 2 When the signal transmitting module 202 and the signal receiving module 203 work simultaneously, the comparison unit 2051 is further used to compare the second propagation delay phase with the reference propagation delay phase and to compare the second correlation amplitude with the reference correlation amplitude to obtain the wearing status of the wearable device.

[0276] It can be understood that, in some other embodiments, when the absolute value of the difference between the second propagation delay phase and the reference propagation delay phase is less than a first preset threshold, and the absolute value of the difference between the second correlation amplitude and the reference correlation amplitude is less than a second preset threshold, the wearable device is in an unworn state; when the absolute value of the difference between the second propagation delay phase and the reference propagation delay phase is greater than the first preset threshold, the absolute value of the difference between the second correlation amplitude and the reference correlation amplitude is greater than the second preset threshold, and the second correlation amplitude corresponding to adjacent integration time periods increases over time, the wearable device is in a worn state; when the absolute value of the difference between the second propagation delay phase and the reference propagation delay phase is greater than the first preset threshold, the absolute value of the difference between the second correlation amplitude and the reference correlation amplitude is greater than the second preset threshold, and the second correlation amplitude corresponding to adjacent integration time periods remains unchanged, the wearable device is in a worn state; when the absolute value of the difference between the second propagation delay phase and the reference propagation delay phase is greater than the first preset threshold, the absolute value of the difference between the second correlation amplitude and the reference correlation amplitude is greater than the second preset threshold, and the second correlation amplitude corresponding to adjacent integration time periods decreases over time, the wearable device is in a removed state.

[0277] Please continue to refer to Figure 2 The detection control module 205 further includes: a control unit 2052 connected to the comparison unit 2051, configured to switch the working mode of the wearable device according to the wearing state of the wearable device.

[0278] Specifically, in this embodiment, the working modes of the wearable device include low power consumption mode (i.e., standby mode) and normal mode; if the wearable device is in a not-worn state, the control unit 2052 controls the wearable device to be in low power consumption mode; if the wearable device is in a worn state, the control unit 2052 switches the wearable device from low power consumption mode to normal mode; if the wearable device is in a worn state, the control unit 2052 maintains the wearable device in normal mode; if the wearable device is in a removed state, the control unit 2052 switches the wearable device from normal mode to low power consumption mode. In addition, the control unit 2052 can also be connected to the signal generating module 201, and when the wearable device is in the worn state, the control unit 2052 controls the signal generating module 201 to reduce the frequency of the single-tone signal to reduce interference with the normal operation of the wearable device; in addition, the control unit 2052 can also control the periodic interval of transmitting the single-tone signal, the pulse length of the single-tone signal, and the length of the integration time period, etc.; the period, frequency, etc. of the single-tone signal, the reflected signal and the attenuated signal are all consistent, but the present invention is not limited to this.

[0279] In summary, the present embodiment provides a wearing detection method and system for a wearable device, which can generate a single-tone signal and its orthogonal signal, and receive a reflected signal after the single-tone signal is transmitted, so as to calculate the propagation delay phase according to the single-tone signal, the orthogonal signal, the reflected signal and the preset sliding integration time, thereby obtaining the wearing status of the wearable device according to the propagation delay phase. In this embodiment, the preset sliding integration time is an integer multiple of the half-cycle of the single-tone signal, so that the propagation delay phase obtained by the sliding correlation integral operation and phase calculation is independent of the amplitude of the reflected signal, which can avoid the detection error caused by the amplitude jitter of the reflected signal in the prior art, thereby improving the accuracy of the wearable device wearing status detection; at the same time, it does not require a complex receiving front-end amplifier circuit, and has a low requirement for the width of the single-tone signal. At the same time, the setting of the integration time period in this embodiment makes the amount of data required to be cached during the sliding correlation integral operation and phase calculation small, the requirements for computing resources and storage resources are low, and the processing delay is small.

[0280] Although the present invention has been described in detail through the above preferred embodiments, it should be understood that the above description is not intended to limit the present invention. After reading the above description, various modifications and substitutions of the present invention will become apparent to those skilled in the art. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A wearing detection method for a wearable device, characterized in that: include: generating a single tone signal and a quadrature signal of the single tone signal; transmitting the single tone signal and receiving a reflected signal of the single tone signal; Calculate the propagation delay phase according to the single tone signal, the orthogonal signal, the reflected signal and a preset sliding integration time; as well as Acquire the wearing state of the wearable device according to the propagation delay phase; When receiving the reflected signal, an attenuated signal of the single-tone signal is also received simultaneously, and the step of calculating the propagation delay phase according to the single-tone signal, the orthogonal signal, the reflected signal and the preset sliding integration time includes: performing sliding correlation integration on the single tone signal and the reflected signal, and performing sliding correlation integration on the single tone signal and the attenuated signal according to the preset sliding integration time, to obtain a third sliding correlation result; performing sliding correlation integration on the orthogonal signal and the reflected signal and performing sliding correlation integration on the orthogonal signal and the attenuated signal according to the preset sliding integration time to obtain a fourth sliding correlation result; and Calculating a second propagation delay phase and a second correlation amplitude according to the third sliding correlation result and the fourth sliding correlation result; Also includes: performing sliding correlation integration on the single tone signal and the attenuated signal according to the preset sliding integration time to obtain a fifth sliding correlation result; performing sliding correlation integration on the orthogonal signal and the attenuation signal according to the preset sliding integration time to obtain a sixth sliding correlation result; and Calculate a reference propagation delay phase and a reference correlation amplitude according to the fifth sliding correlation result and the sixth sliding correlation result; The wearing state of the wearable device is acquired according to the difference between the second propagation delay phase and the reference propagation delay phase and the difference between the second correlation amplitude and the reference correlation amplitude.

2. The wearing detection method for a wearable device according to claim 1, wherein: The wearing status includes one or any combination of not wearing, wearing, worn and removed.

3. The wearing detection method of a wearable device according to claim 2, wherein: The preset sliding integration time is an integer multiple of a half period of the single tone signal.

4. The wearing detection method for a wearable device according to claim 3, wherein: The step of calculating the propagation delay phase according to the single-tone signal, the orthogonal signal, the reflected signal and the preset sliding integration time comprises: Performing sliding correlation integration on the single tone signal and the reflected signal according to the preset sliding integration time to obtain a first sliding correlation result; Performing sliding correlation integration on the orthogonal signal and the reflected signal according to the preset sliding integration time to obtain a second sliding correlation result; and A first propagation delay phase and a first correlation amplitude are calculated according to the first sliding correlation result and the second sliding correlation result.

5. The wearing detection method for a wearable device according to claim 4, wherein: The first sliding correlation result is calculated using the following formula: Wherein, CORI(T) is the first sliding correlation result; sin(ωt) is the single tone signal, ω is the frequency of the single tone signal, and t is time; A1sin(ωt+θ1) is the reflected signal, A1 is the amplitude of the reflected signal, and θ1 is the propagation delay phase of the reflected signal; T is the preset sliding integration time; τ~τ+T is the integration time period, and τ represents the integration start time; The second sliding correlation result is calculated using the following formula: Wherein, CORQ(T) is the second sliding correlation result; cos(ωt) is the orthogonal signal; The first propagation delay phase is calculated using the following formula: Wherein, θ is the first propagation delay phase; The first correlation amplitude is calculated using the following formula: Wherein, ampt is the first correlation amplitude.

6. The wearing detection method for a wearable device according to claim 5, wherein: The step of obtaining the wearing state of the wearable device according to the propagation delay phase includes: The first propagation delay phases corresponding to adjacent integration time periods change randomly, and the wearable device is in an unworn state; The first propagation delay phase corresponding to adjacent integration time periods decreases over time, and the wearable device is in a wearing state; The first propagation delay phase corresponding to adjacent integration time periods remains unchanged, and the wearable device is in a worn state; and The first propagation delay phase corresponding to adjacent integration time periods increases with time, and the wearable device is in a removal state.

7. The wearing detection method for a wearable device according to claim 5, wherein: Also includes: Acquire a wearing state of the wearable device according to the first correlation amplitude; The step of obtaining the wearing status of the wearable device according to the first correlation amplitude includes: The first correlation amplitude is less than a first reference threshold, and the wearable device is in an unworn state; The first correlation amplitude is greater than a first reference threshold and the first correlation amplitudes corresponding to adjacent integration time periods increase over time, and the wearable device is in a wearing state; The first correlation amplitude is greater than a first reference threshold and the first correlation amplitudes corresponding to adjacent integration time periods remain unchanged, and the wearable device is in a worn state; and The first correlation amplitude is greater than a first reference threshold and the first correlation amplitudes corresponding to adjacent integration time periods decrease over time, indicating that the wearable device is in a removal state.

8. The wearing detection method for a wearable device according to claim 1, wherein: The third sliding correlation result is calculated using the following formula: Wherein, CORI′(T) is the third sliding correlation result; sin(ωt) is the single-tone signal, ω is the frequency of the single-tone signal, and t is time; A1sin(ωt+θ1) is the reflected signal, A1 is the amplitude of the reflected signal, and θ1 is the propagation delay phase of the reflected signal; T is the preset sliding integration time; τ~τ+T is the integration time period, and τ represents the starting time of integration; A2sin(ωt+θ2) is the attenuated signal, A2 is the amplitude of the attenuated signal, and θ2 is the propagation delay phase of the attenuated signal; The fourth sliding correlation result is calculated using the following formula: Wherein, CORQ′(T) is the fourth sliding correlation result; The second propagation delay phase is calculated using the following formula: Wherein, θ' is the second propagation delay phase; The second correlation amplitude is calculated using the following formula: Wherein, ampt' is the second correlation amplitude.

9. The wearing detection method for a wearable device according to claim 8, wherein: The fifth sliding correlation result is calculated using the following formula: Among them, CORI r (T) is the fifth sliding related result; The sixth sliding correlation result is calculated using the following formula: Among them, CORQ r (T) is the sixth sliding related result; The reference propagation delay phase is calculated using the following formula: Among them, θ r is the reference propagation delay phase; The reference correlation amplitude is calculated using the following formula: Among them, ampt r is the reference correlation amplitude.

10. The wearing detection method for a wearable device according to claim 1, wherein: The step of obtaining the wearing state of the wearable device according to the propagation delay phase includes: When the absolute value of the difference between the second propagation delay phase and the reference propagation delay phase is less than a first preset threshold, and the absolute value of the difference between the second correlation amplitude and the reference correlation amplitude is less than a second preset threshold, the wearable device is in an unworn state; When the absolute value of the difference between the second propagation delay phase and the reference propagation delay phase is greater than a first preset threshold, the absolute value of the difference between the second correlation amplitude and the reference correlation amplitude is greater than a second preset threshold, and the second correlation amplitudes corresponding to adjacent integration time periods increase over time, the wearable device is in a worn state; The absolute value of the difference between the second propagation delay phase and the reference propagation delay phase is greater than a first preset threshold, the absolute value of the difference between the second correlation amplitude and the reference correlation amplitude is greater than a second preset threshold, and the second correlation amplitudes corresponding to adjacent integration time periods remain unchanged, and the wearable device is in a worn state; When the absolute value of the difference between the second propagation delay phase and the reference propagation delay phase is greater than a first preset threshold, the absolute value of the difference between the second correlation amplitude and the reference correlation amplitude is greater than a second preset threshold, and the second correlation amplitude corresponding to adjacent integration time periods decreases over time, the wearable device is in a removal state.

11. A wear detection system for a wearable device, used for a wearable device, characterized in that: include: A signal generating module, configured to generate a single tone signal and an orthogonal signal of the single tone signal; A signal transmitting module, connected to the signal generating module, for transmitting the single tone signal; A signal receiving module, configured to receive a reflected signal of the single tone signal; a phase calculation module, connected to the signal receiving module and the signal generating module respectively, for calculating the propagation delay phase according to the single tone signal, the orthogonal signal, the reflected signal and a preset sliding integration time; as well as a detection control module, connected to the phase calculation module, configured to obtain a wearing state of the wearable device according to the propagation delay phase; The phase calculation module includes: a correlation integration unit connected to the signal receiving module and the signal generating module; a phase calculation unit connected to the correlation integration unit; The detection control module includes: a comparison unit connected to the phase calculation unit; When the signal receiving module receives the reflected signal, it also receives the attenuation signal of the single-tone signal; the correlation integration unit is further configured to perform sliding correlation integration on the single-tone signal and the reflected signal and on the single-tone signal and the attenuation signal according to the preset sliding integration time to obtain a third sliding correlation result; and performing sliding correlation integration on the orthogonal signal and the reflected signal, and performing sliding correlation integration on the orthogonal signal and the attenuated signal according to the preset sliding integration time, to obtain a fourth sliding correlation result; The phase calculation unit is further configured to calculate a second propagation delay phase and a second correlation amplitude according to the third sliding correlation result and the fourth sliding correlation result; The correlation integration unit is further configured to perform sliding correlation integration on the single tone signal and the attenuated signal according to the preset sliding integration time to obtain a fifth sliding correlation result; and performing sliding correlation integration on the orthogonal signal and the attenuation signal according to the preset sliding integration time to obtain a sixth sliding correlation result; The phase calculation unit is further configured to calculate a reference propagation delay phase and a reference correlation amplitude based on the fifth sliding correlation result and the sixth sliding correlation result; The comparing unit is further configured to compare the second propagation delay phase with the reference propagation delay phase and to compare the second correlation amplitude with the reference correlation amplitude to obtain a wearing state of the wearable device.

12. The wearing detection system for a wearable device according to claim 11, wherein: The wearing status includes one or any combination of not wearing, wearing, worn and removed.

13. The wearing detection system for a wearable device according to claim 12, wherein: The preset sliding integration time is an integer multiple of a half period of the single tone signal.

14. The wearing detection system for a wearable device according to claim 13, wherein: The correlation integration unit is configured to perform sliding correlation integration on the single tone signal and the reflected signal according to the preset sliding integration time to obtain a first sliding correlation result; and performing sliding correlation integration on the orthogonal signal and the reflected signal according to the preset sliding integration time to obtain a second sliding correlation result; The phase calculation unit is configured to calculate a first propagation delay phase and a first correlation amplitude according to the first sliding correlation result and the second sliding correlation result.

15. The wearing detection system for a wearable device according to claim 14, wherein: The first sliding correlation result is calculated using the following formula: Wherein, CORI(T) is the first sliding correlation result; sin(ωt) is the single tone signal, ω is the frequency of the single tone signal, and t is time; A1sin(ωt+θ1) is the reflected signal, A1 is the amplitude of the reflected signal, and θ1 is the propagation delay phase of the reflected signal; T is the preset sliding integration time; τ~τ+T is the integration time period, and τ represents the integration start time; The second sliding correlation result is calculated using the following formula: Wherein, CORQ(T) is the second sliding correlation result; cos(ωt) is the orthogonal signal; The first propagation delay phase is calculated using the following formula: Wherein, θ is the first propagation delay phase; The first correlation amplitude is calculated using the following formula: Wherein, ampt is the first correlation amplitude.

16. The wearing detection system for a wearable device according to claim 15, wherein: The comparing unit is configured to compare the first propagation delay phases and / or the first correlation amplitudes of adjacent integration time periods to obtain a wearing state of the wearable device.

17. The wearing detection system for a wearable device according to claim 16, wherein: The first propagation delay phases corresponding to adjacent integration time periods change randomly, and the wearable device is in an unworn state; The first propagation delay phase corresponding to adjacent integration time periods decreases over time, and the wearable device is in a wearing state; The first propagation delay phase corresponding to adjacent integration time periods remains unchanged, and the wearable device is in a worn state; and The first propagation delay phase corresponding to adjacent integration time periods increases with time, and the wearable device is in a removal state.

18. The wearing detection system for a wearable device according to claim 16, wherein: The first correlation amplitude is less than a first reference threshold, and the wearable device is in an unworn state; The first correlation amplitude is greater than a first reference threshold and the first correlation amplitudes corresponding to adjacent integration time periods increase over time, and the wearable device is in a wearing state; The first correlation amplitude is greater than a first reference threshold and the first correlation amplitudes corresponding to adjacent integration time periods remain unchanged, and the wearable device is in a worn state; and The first correlation amplitude is greater than a first reference threshold and the first correlation amplitudes corresponding to adjacent integration time periods decrease over time, indicating that the wearable device is in a removal state.

19. The wearing detection system for a wearable device according to claim 11, wherein: The third sliding correlation result is calculated using the following formula: Wherein, CORI′(T) is the third sliding correlation result; sin(ωt) is the single-tone signal, ω is the frequency of the single-tone signal, and t is time; A1sin(ωt+θ1) is the reflected signal, A1 is the amplitude of the reflected signal, and θ1 is the propagation delay phase of the reflected signal; T is the preset sliding integration time; τ~τ+T is the integration time period, and τ represents the starting time of integration; A2sin(ωt+θ2) is the attenuated signal, A2 is the amplitude of the attenuated signal, and θ2 is the propagation delay phase of the attenuated signal; The fourth sliding correlation result is calculated using the following formula: Wherein, CORQ′(T) is the fourth sliding correlation result; The second propagation delay phase is calculated using the following formula: Wherein, θ' is the second propagation delay phase; The second correlation amplitude is calculated using the following formula: Wherein, ampt' is the second correlation amplitude.

20. The wearing detection system for a wearable device according to claim 19, wherein: The fifth sliding correlation result is calculated using the following formula: Among them, CORI r (T) is the fifth sliding related result; The sixth sliding correlation result is calculated using the following formula: Among them, CORQ r (T) is the sixth sliding related result; The reference propagation delay phase is calculated using the following formula: Among them, θ r is the reference propagation delay phase; The reference correlation amplitude is calculated using the following formula: Among them, ampt r is the reference correlation amplitude.

21. The wearing detection system for a wearable device according to claim 11, wherein: When the absolute value of the difference between the second propagation delay phase and the reference propagation delay phase is less than a first preset threshold, and the absolute value of the difference between the second correlation amplitude and the reference correlation amplitude is less than a second preset threshold, the wearable device is in an unworn state; When the absolute value of the difference between the second propagation delay phase and the reference propagation delay phase is greater than a first preset threshold, the absolute value of the difference between the second correlation amplitude and the reference correlation amplitude is greater than a second preset threshold, and the second correlation amplitudes corresponding to adjacent integration time periods increase over time, the wearable device is in a worn state; The absolute value of the difference between the second propagation delay phase and the reference propagation delay phase is greater than a first preset threshold, the absolute value of the difference between the second correlation amplitude and the reference correlation amplitude is greater than a second preset threshold, and the second correlation amplitudes corresponding to adjacent integration time periods remain unchanged, and the wearable device is in a worn state; When the absolute value of the difference between the second propagation delay phase and the reference propagation delay phase is greater than a first preset threshold, the absolute value of the difference between the second correlation amplitude and the reference correlation amplitude is greater than a second preset threshold, and the second correlation amplitude corresponding to adjacent integration time periods decreases over time, the wearable device is in a removal state.

22. The wearing detection system for a wearable device according to claim 11 or 16, wherein: The detection control module further includes: a control unit connected to the comparison unit, configured to switch an operating mode of the wearable device according to a wearing state of the wearable device.

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