A perception method and apparatus
By combining Wi-Fi sensing methods from the Sub-7GHz and mmWave bands, and using timestamps and phase change information to match communication data frames, the limitations of each band are overcome, achieving high-resolution and high-precision Wi-Fi sensing effects.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HUAWEI TECH CO LTD
- Filing Date
- 2022-09-29
- Publication Date
- 2026-05-29
AI Technical Summary
Existing Wi-Fi sensing technologies have limitations in both the Sub-7GHz and mmWave bands. The Sub-7GHz band has limited distance resolution and is difficult to capture small movements, while the mmWave band is prone to phase ambiguity and is difficult to capture large or high-speed movements.
By combining the Sub-7GHz band and the mmWave band for Wi-Fi sensing, and by receiving and matching communication data frames from the two bands, frame matching is performed using timestamps and phase change information, thereby improving sensing performance.
It achieves high distance resolution and high-precision micro-motion detection, while resisting phase ambiguity, thus improving the sensing performance of Wi-Fi signals.
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Figure CN122120930A_ABST
Abstract
Description
[0001] This application claims priority to Chinese Patent Application No. 202210727163.4, filed with the State Intellectual Property Office of China on June 24, 2022, entitled “A Wi-Fi Sensing Method”, the entire contents of which are incorporated herein by reference.
[0002] This application is a divisional application. The original application has the application number 202211201922.X and the original application date is September 29, 2022. The entire contents of the original application are incorporated herein by reference. Technical Field
[0003] This application relates to the field of communication technology, and in particular to a sensing method and apparatus. Background Technology
[0004] Wireless-Fidelity (Wi-Fi) technology is used in applications in the field of wireless sensing, such as intrusion detection, motion recognition, and gesture recognition.
[0005] Based on frequency bands, current Wi-Fi communication standards can be roughly divided into two categories: Sub-7GHz band and mmWave band. In Wi-Fi sensing technology, the higher the bandwidth used for transmitting and receiving Wi-Fi signals, the finer the resolution of the determined environment and / or human distance. Because the Sub-7GHz band is in a low-frequency range, its bandwidth is relatively limited, resulting in limited distance resolution in applications involving sensing distance information. Furthermore, in applications sensing motion information, due to the lower frequency and longer carrier wavelength of the Sub-7GHz band, the phase change is smaller, and phase noise significantly interferes with motion information calculation. Therefore, the Sub-7GHz band lacks sufficient precision for capturing small movements, and the sensing performance of Wi-Fi signals in the Sub-7GHz band is limited.
[0006] Although the mmWave band has a higher frequency and higher distance resolution, and can capture high-precision micro-motion information, its shorter carrier wavelength and larger phase change make it prone to phase ambiguity, making it difficult to capture targets with large amplitude or high speed. The sensing performance of Wi-Fi signals in the mmWave band is limited. Summary of the Invention
[0007] This application provides a sensing method and apparatus that can combine the Sub-7GHz band and the mmWave band for Wi-Fi sensing, thereby improving the sensing performance of Wi-Fi signals.
[0008] To achieve the above objectives, the embodiments of this application adopt the following technical solutions: In a first aspect, a sensing method is provided, which simultaneously employs a first frequency band and a second frequency band for sensing, wherein the frequency of the first frequency band is higher than the frequency of the second frequency band. The method includes: receiving multiple communication data frames of the first frequency band and multiple communication data frames of the second frequency band; acquiring multiple pairs of communication data frames, wherein each pair of communication data frames includes a first communication data frame from the multiple communication data frames of the first frequency band and a second communication data frame from the multiple communication data frames of the second frequency band, wherein the time difference between the first timestamp of the first communication data frame and the second timestamp of the second communication data frame is within a preset threshold range.
[0009] That is, the transmitting device used for sensing can simultaneously send communication data frames in the first frequency band and the second frequency band to the receiving device. When each communication data frame carries a timestamp, the receiving device or a third-party device can match the communication data frames in the two frequency bands according to the timestamp carried by each communication data frame to obtain multiple pairs of communication data frames. In the embodiments of this application, the high-frequency first frequency band generally has the advantages of high distance resolution and high-precision micro-motion detection. The low-frequency second frequency band generally has the advantage of strong resistance to phase ambiguity. If the communication data frames in the two frequency bands are frame matched, each pair of communication data frames can be combined for Wi-Fi sensing, so that Wi-Fi sensing not only has the advantages of high distance resolution and high-precision micro-motion detection, but also has the advantage of strong resistance to phase ambiguity, thereby improving the performance of Wi-Fi sensing.
[0010] In one possible design, the first communication data frame includes a first timestamp, which is the timestamp of the transmission of the first communication data frame; the second communication data frame includes a second timestamp, which is the timestamp of the transmission of the second communication data frame.
[0011] That is, when the time difference between the transmission timestamp of the first communication data frame in the first frequency band and the transmission timestamp of the second communication data frame in the second frequency band is within a preset threshold range, the first communication data frame and the second communication data frame are matched to form a pair of communication data frames.
[0012] Alternatively, in another possible design, the two communication data frames with the closest transmission timestamps under the two frequency bands can be matched into a pair of communication data frames.
[0013] Alternatively, in another possible design, when the receiving device receives communication data frames in two frequency bands, it can also match the communication data frames in the two frequency bands based on the timestamp of the received communication data frames.
[0014] In one possible design, for the same target encountered by signals in the first and second frequency bands during propagation, the first phase change information between adjacent communication data frames in multiple communication data frames of the first frequency band is obtained; The first phase change information between adjacent communication data frames in the first frequency band is calculated based on the phase change information between adjacent communication data frames in the second frequency band, the time interval between adjacent communication data frames in the first frequency band, and the time interval between adjacent communication data frames in the second frequency band.
[0015] This is because, while the distance resolution in the first frequency band is high, it is prone to phase ambiguity, meaning its resistance to phase ambiguity is poor. Therefore, the phase change information between consecutive communication data frames can be obtained in the second frequency band. Based on the previous matching of communication data frames between the two frequency bands, this application can convert the phase change information in the second frequency band to the phase change information in the first frequency band. This is equivalent to combining the strong resistance to phase ambiguity of the second frequency band with the high distance resolution and high-precision micro-motion detection advantages of the first frequency band for each pair of communication data frames, thereby improving the sensing performance of Wi-Fi signals.
[0016] In one possible design, adjacent communication data frames in the first frequency band include a third communication data frame and a fourth communication data frame, and adjacent communication data frames in the second frequency band include a fifth communication data frame and a sixth communication data frame. The third and fifth communication data frames are one pair of communication data frames in a plurality of pairs of communication data frames, and the fourth and sixth communication data frames are one pair of communication data frames in a plurality of pairs of communication data frames. The calculation method for the first phase change information between the third and fourth communication data frames includes:
[0017] in, This indicates the first phase change information between the third and fourth communication data frames. This indicates the phase change information between the fifth and sixth communication data frames. This represents the time interval between the timestamps of the third and fourth communication data frames. This indicates the time interval between the timestamps of the fifth and sixth communication data frames. This indicates the subcarrier wavelength in the first frequency band. This indicates the subcarrier wavelength in the second frequency band.
[0018] In one possible design, for the same target encountered by signals in the first and second frequency bands during propagation, the second phase change information between adjacent communication data frames in the first frequency band is determined based on the first phase change information between adjacent communication data frames in the first frequency band. The second phase change information is calculated based on the relationship between the original phase change information and coefficients between adjacent communication data frames in multiple communication data frames of the first frequency band. The coefficient is used to indicate that the phase difference between the second phase change information and the original phase change information is an integer multiple of 2π, where π is the constant of pi.
[0019] In one possible design, based on the first phase change information between the third and fourth communication data frames, the coefficients are expressed as:
[0020] in, Represents the coefficient. This represents the phase difference between the original phase information of the third communication data frame and the original phase information of the fourth communication data frame. n is an integer, and round() represents the rounding operation.
[0021] This is because the calculated phase change information in the first frequency band is still significantly affected by phase noise. Typically, the difference between the calculated phase change information in the first frequency band and the phase difference between the actual detected communication data frames in the second frequency band is... In order to remove phase noise from the bit change information of the first frequency band as much as possible, this application can further optimize the bit change information of the first frequency band using high-precision original phase information in continuous communication data frames corresponding to the first frequency band.
[0022] In one possible design, the first frequency band is the mmWave band, and the second frequency band is the Sub-7GHz band. The Sub-7GHz band, being in a low-frequency range, has relatively limited bandwidth, resulting in limited range resolution for distance sensing applications. While it can capture large-amplitude motion, it lacks the precision needed to capture small-amplitude motion. The mmWave band, on the other hand, is in a high-frequency range with a shorter carrier wavelength, resulting in higher range resolution. The mmWave band also has the advantage of strong resistance to phase ambiguity.
[0023] Secondly, a sensing device is provided, which simultaneously uses a first frequency band and a second frequency band for sensing, wherein the frequency of the first frequency band is higher than the frequency of the second frequency band. The sensing device includes: a receiving unit for receiving multiple communication data frames of the first frequency band and multiple communication data frames of the second frequency band; and a data frame matching unit for acquiring multiple pairs of communication data frames, wherein each pair of communication data frames includes a first communication data frame from the multiple communication data frames of the first frequency band and a second communication data frame from the multiple communication data frames of the second frequency band, wherein the time difference between the first timestamp of the first communication data frame and the second timestamp of the second communication data frame is within a preset threshold range.
[0024] For the beneficial effects of the second aspect, please refer to the explanation of the first aspect.
[0025] In one possible design, the first communication data frame includes a first timestamp, which is the timestamp of the transmission of the first communication data frame; the second communication data frame includes a second timestamp, which is the timestamp of the transmission of the second communication data frame.
[0026] In one possible design, a phase acquisition unit is also included, used to: acquire first phase change information between adjacent communication data frames in multiple communication data frames of the first frequency band for the same target encountered by signals in the first and second frequency bands during propagation; wherein the first phase change information between adjacent communication data frames in multiple communication data frames of the first frequency band is calculated based on the phase change information between adjacent communication data frames in multiple communication data frames of the second frequency band, the time interval between adjacent communication data frames in multiple communication data frames of the first frequency band, and the time interval between adjacent communication data frames in multiple communication data frames of the second frequency band.
[0027] In one possible design, adjacent communication data frames in the first frequency band include a third and a fourth communication data frame, and adjacent communication data frames in the second frequency band include a fifth and a sixth communication data frame. The third and fifth communication data frames are one pair of multiple pairs of communication data frames, and the fourth and sixth communication data frames are also one pair of multiple pairs of communication data frames. The calculation method for the first phase change information between the third and fourth communication data frames includes:
[0028] in, This indicates the first phase change information between the third and fourth communication data frames. This indicates the phase change information between the fifth and sixth communication data frames. This represents the time interval between the timestamps of the third and fourth communication data frames. This indicates the time interval between the timestamps of the fifth and sixth communication data frames. This indicates the subcarrier wavelength in the first frequency band. This indicates the subcarrier wavelength in the second frequency band.
[0029] In one possible design, the phase acquisition unit is also used to: determine, based on the first phase change information between adjacent communication data frames in the first frequency band, the second phase change information between adjacent communication data frames in the first frequency band, for the same target encountered by the signals of the first frequency band and the second frequency band during propagation; The second phase change information is calculated based on the relationship between the original phase change information and coefficients between adjacent communication data frames in the first frequency band. The coefficients are used to indicate that the phase difference between the second phase change information and the original phase change information is an integer multiple of 2π, where π is the constant of pi.
[0030] In one possible design, based on the first phase change information between the third and fourth communication data frames, the coefficients are expressed as:
[0031] in, Represents the coefficient. This represents the phase difference between the original phase information of the third communication data frame and the original phase information of the fourth communication data frame. n is an integer, and round() represents the rounding operation.
[0032] In one possible design, the first frequency band is the mmWave band, and the second frequency band is the Sub-7GHz band.
[0033] Thirdly, a communication device is provided, comprising at least one processor connected to a memory, the at least one processor being configured to read and execute a program stored in the memory, such that the device performs the method as described in the first aspect or any of the first aspects above.
[0034] Fourthly, a chip coupled to a memory is provided for reading and executing program instructions stored in the memory to implement the method as described in the first aspect or any one of the first aspects above.
[0035] Fifthly, embodiments of this application provide a sensing device included in an electronic device, which has the function of implementing the behaviors of the electronic device in any of the above aspects and any possible implementations. This function can be implemented in hardware or by hardware executing corresponding software. The hardware or software includes one or more modules or units corresponding to the above functions. For example, a receiving module or unit, a data frame matching module or unit, and a phase acquisition module or unit, etc.
[0036] In a sixth aspect, embodiments of this application provide a computer-readable storage medium including computer instructions that, when executed on an electronic device, cause the electronic device to perform the antenna gain adjustment method described in the first aspect and any possible implementation thereof.
[0037] In a seventh aspect, embodiments of this application provide a computer program product that, when run on a computer or processor, causes the computer or processor to execute the perception method described in the first aspect and any possible implementation thereof.
[0038] Eighthly, embodiments of this application provide a system that may include a sensing device and a transmitting device as described in any possible implementation of the second aspect above. The transmitting device may transmit communication data frames in two frequency bands to the sensing device. The sensing device and the transmitting device may execute the sensing method described in the first aspect and any possible implementation thereof.
[0039] It is understood that any of the sensing devices, sensing equipment, chips, computer-readable storage media, or computer program products provided above can be applied to the corresponding methods provided above. Therefore, the beneficial effects they can achieve can be referred to the beneficial effects in the corresponding methods, and will not be repeated here.
[0040] These or other aspects of this application will become more readily apparent in the following description. Attached Figure Description
[0041] Figure 1 A schematic diagram of a network architecture provided for an embodiment of this application; Figure 2 This application provides a schematic diagram of a network architecture in a Wi-Fi environment where the transmitting device is a router and the receiving device is a laptop computer. Figure 3 A flowchart illustrating a sensing method provided in an embodiment of this application; Figure 4 A flowchart illustrating a sensing method provided in an embodiment of this application; Figure 5 An mmWave frequency band provided for embodiments of this application ( Figure 5 The first frequency band in the middle) and the Sub-7GHz band ( Figure 5 A schematic diagram of multiple pairs of communication data frames after matching communication data frames in the second frequency band (in the second frequency band); Figure 6 A schematic diagram illustrating the distance information of two targets in the Sub-7GHz band and mmWave band, provided for embodiments of this application; Figure 7 A schematic diagram of multipath information between a person and a transmitting and receiving device is provided as an embodiment of this application; Figure 8 This application provides a schematic diagram illustrating the distance information between a person and a transmitting device when the person is between a transmitting device and a receiving device. Figure 9 A schematic diagram illustrating the time interval between communication data frames in a first frequency band and a second frequency band, provided as an embodiment of this application; Figure 10 This is a schematic diagram of the structure of a sensing device provided in an embodiment of this application; Figure 11 This is a schematic diagram of the structure of a sensing device provided in an embodiment of this application. Detailed Implementation
[0042] For ease of understanding, the examples provide explanations of some concepts related to the embodiments of this application for reference. As shown below: Millimeter wave (mmWave): A type of electromagnetic wave with a specific frequency range, usually defined as 30 GHz to 300 GHz, corresponding to wavelengths of 10 mm to 1 mm, hence the name millimeter wave.
[0043] Channel state information (CSI): In wireless communication, CSI describes the state of a signal along each propagation path. This information describes how a signal propagates from the transmitter to the receiver through the channel, such as signal scattering. It characterizes a combination of factors, such as environmental attenuation and distance attenuation. CSI enables communication systems to adapt to current channel conditions, ensuring high-reliability and high-speed communication in multi-antenna systems.
[0044] The technical solutions of the embodiments of this application will be described below with reference to the accompanying drawings. In the description of the embodiments of this application, unless otherwise stated, " / " means "or," for example, A / B can mean A or B; "and / or" in this text is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Furthermore, in the description of the embodiments of this application, "multiple" refers to two or more than two.
[0045] Hereinafter, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this embodiment, unless otherwise stated, "a plurality of" means two or more.
[0046] Wi-Fi, as a widely used wireless network transmission technology, has undergone multiple generations of standard evolution. Based on frequency bands, current Wi-Fi communication standards can be roughly divided into two categories: 1) Sub-7GHz band: including Institute of Electrical and Electronics Engineers (IEEE) 802.11 a / g / n / g and IEEE 802.11ax, IEEE 802.11be, mainly covering the 2.4GHz, 5GHz and 6GHz bands.
[0047] 2) mmWave band: including IEEE 802.11 ad / ay, mainly covering the 45GHz and 60GHz bands.
[0048] Beyond communication functions, many academic studies are exploring the application of Wi-Fi technology in the field of wireless sensing, such as intrusion detection, motion recognition, and gesture recognition.
[0049] Wi-Fi sensing technology primarily infers information about the environment and / or human presence during Wi-Fi signal propagation by analyzing Wi-Fi signals. One typical method utilizes CSI data specified in existing Wi-Fi standards. CSI data typically contains information about multiple subcarriers using Orthogonal Frequency Division Multiplexing (OFDM) technology. By analyzing CSI data, information such as direct path distance, human movement, and breathing / heartbeat can be estimated.
[0050] Distance information can be analyzed based on the differences between different subcarriers at the same time. A typical approach is to process the information of all subcarriers at the same time using the Inverse Discrete Fourier Transform (IFT). This involves considering the distance resolution of the environment and / or the human body. It is related to the total bandwidth B of the signal, and the relationship can be expressed as shown in formula (1).
[0051] (1) As can be seen from formula (1), the higher the total bandwidth B of the signal, the greater the distance resolution. The smaller the value, the finer the distance resolution.
[0052] For motion information, analysis can be performed based on the phase change of the same carrier at consecutive observation times, i.e., the Doppler effect. A typical method is to process the phase information of subcarriers of the same frequency at consecutive observation times using the Discrete Fourier Transform (DFT). Each Wi-Fi frame can be considered as an observation time, observing the motion information of the environment and / or the human body. With phase change The relationship can be expressed as shown in formula (2).
[0053] (2) in, For subcarrier wavelength. Motion information. With phase change Proportional.
[0054] For the same motion information, The relationship between the wavelength of the carrier wave and the wavelength of the subcarrier can be shown in formula (3).
[0055] (3) That is, under the same motion information, the shorter the wavelength of the subcarrier, the greater the phase change. The larger the value, the more important it is to ensure that the phase change between adjacent observation times is maintained to prevent blurring. It meets the requirements of formula (4).
[0056] (4) In this embodiment, distance information and motion information can be collectively referred to as perception information.
[0057] Motion information can be understood as the speed information of the environment and / or the human body, which can be used to create coordinate graphs and analyze the behavior, gestures and actions of the environment and / or the human body.
[0058] Current sensing technologies can be analyzed based on either the Sub-7GHz band or the mmWave band, but each of these frequencies has its own limitations.
[0059] The Sub-7GHz band has relatively limited bandwidth due to its low frequency (the current known maximum bandwidth is 320MHz). In applications involving distance sensing, the distance resolution of the Sub-7GHz band is limited. Furthermore, in applications involving motion sensing, due to the low frequency and long carrier wavelength, according to the above formula (2), the phase noise... It has a significant impact on motion information calculation. Although it has the advantage of strong resistance to phase ambiguity, it is not precise enough for capturing small-amplitude motions.
[0060] The mmWave band is a high-frequency band with a relatively high frequency and a short carrier wavelength, resulting in high distance resolution and the ability to capture small-amplitude motions. However, according to the above formulas (3) and (4), in applications that sense motion information, phase ambiguity is prone to occur in the mmWave band, making it impossible to capture larger-amplitude motions.
[0061] In response, this application proposes a Wi-Fi sensing method that combines high-frequency and low-frequency bands, which can complement the advantages of the two frequency bands to improve the sensing performance of Wi-Fi signals.
[0062] In some embodiments, this application can combine the Sub-7GHz band and the mmWave band for Wi-Fi sensing. By matching frames from the two bands using timestamps, the advantages of the Sub-7GHz band's high resistance to phase ambiguity and the advantages of the mmWave band's high frame resolution and high-precision micro-motion detection are combined, thereby improving the sensing performance of Wi-Fi signals.
[0063] like Figure 1 The diagram illustrates a network architecture provided in an embodiment of this application. The network architecture to which the sensing method provided in this application is applied may include a transmitting device and a receiving device. The transmitting and receiving devices can transmit signals via Wi-Fi. The signal transmitted by the transmitting device can be transmitted to the receiving device after passing through the environment and / or a human body. The transmitting or receiving device can sense the signal by its reflection in the environment and / or on the human body, determining distance information, motion information, etc. Alternatively, a third-party device can be used to acquire the reflected signal of the Wi-Fi signal transmitted by the transmitting device in the environment and / or on the human body for sensing.
[0064] For example, the aforementioned transmitting and receiving devices can be devices such as mobile phones, routers, and laptops, which can simultaneously support high-frequency and low-frequency Wi-Fi communication. For instance, they can support Wi-Fi communication in both the Sub-7GHz and mmWave bands. When communication in both the Sub-7GHz and mmWave bands is enabled simultaneously, the transmitting and receiving devices can enter a multi-frequency high data rate mode.
[0065] For example Figure 2 This illustrates a network architecture in a Wi-Fi environment where the transmitting device is a router and the receiving device is a laptop. The router can simultaneously transmit mmWave frequency bands to the laptop. Figure 2 Communication data frames in the first frequency band and the Sub-7GHz band ( Figure 2 Communication data frames in both frequency bands (the second frequency band) can pass through the human body. By reflecting these data frames off the body, the system can sense the distance, movement, breathing, and heart rate of the human body. This sensing can be achieved using a router or laptop, or by a third-party device acquiring communication data frames from both frequency bands to detect these parameters.
[0066] The network architecture of this application embodiment is described below.
[0067] like Figure 3 The diagram shown is a flowchart of a sensing method according to an embodiment of this application. The method uses a first frequency band and a second frequency band for sensing simultaneously. The frequency of the first frequency band is higher than that of the second frequency band. The method includes the following steps.
[0068] 301. The receiving device receives multiple communication data frames from the first frequency band and multiple communication data frames from the second frequency band.
[0069] In other words, the receiving device can simultaneously receive communication data frames from two frequency bands. These communication data frames can be Wi-Fi communication data frames. For example, the receiving device is... Figure 2 When a laptop is in use, it can receive communication data frames from the router in two frequency bands.
[0070] 302. The receiving device acquires multiple pairs of communication data frames. Each pair of communication data frames includes a first communication data frame in multiple communication data frames of the first frequency band and a second communication data frame in multiple communication data frames of the second frequency band. The time difference between the first timestamp of the first communication data frame and the second timestamp of the second communication data frame is within a preset threshold range.
[0071] In some embodiments, a first timestamp is used to indicate the transmission timestamp of a first communication data frame, and a second timestamp is used to indicate the transmission timestamp of a second communication data frame.
[0072] When the receiving device receives communication data frames from the first frequency band and the second frequency band, it can perform frame matching on the communication data frames from the first frequency band and the second frequency band according to the transmission timestamps of the communication data frames to obtain multiple pairs of communication data frames. If the time difference between the first timestamp of the first communication data frame in the first frequency band and the second timestamp of the second communication data frame in the second frequency band is within a preset threshold range, the first communication data frame and the second communication data frame can be considered as a pair of communication data frames.
[0073] Thus, in this embodiment, the high-frequency first band typically offers advantages in high distance resolution and high-precision micro-motion detection. The low-frequency second band typically offers advantages in strong resistance to phase ambiguity. By performing frame matching on the communication data frames from both bands, each pair of communication data frames can be combined for Wi-Fi sensing. This allows Wi-Fi sensing to not only possess the advantages of high distance resolution and high-precision micro-motion detection, but also the advantage of strong resistance to phase ambiguity, thereby improving Wi-Fi sensing performance.
[0074] The following explanation uses the example of the first frequency band being the mmWave band and the second frequency band being the Sub-7GHz band.
[0075] like Figure 4 The diagram shown is a schematic representation of a sensing method and process according to an embodiment of this application. The method uses both the Sub-7GHz band and the mmWave band for sensing, and includes the following process.
[0076] 401. When the transmitting device transmits communication data frames in the first frequency band and communication data frames in the second frequency band, it adds a transmission timestamp to each communication data frame in the first frequency band and adds a transmission timestamp to each communication data frame in the second frequency band.
[0077] Accordingly, the receiving device receives communication data frames in the first frequency band and communication data frames in the second frequency band.
[0078] For example, the transmitting device simultaneously transmits multiple communication data frames in the mmWave band and multiple communication data frames in the Sub-7GHz band. When transmitting the first communication data frame in the mmWave band, the transmitting device adds a transmission timestamp to the first communication data frame; when transmitting the second communication data frame in the Sub-7GHz band, the transmitting device adds a transmission timestamp to the second communication data frame.
[0079] That is, the first communication data frame includes a first timestamp, which is the timestamp of the transmission of the first communication data frame. The second communication data frame includes a second timestamp, which is the timestamp of the transmission of the second communication data frame.
[0080] Among them, multiple communication data frames under the mmWave band are not completely identical, and multiple communication data frames under the Sub-7GHz band are also not completely identical.
[0081] 402. The receiving device obtains the transmission timestamps of the received communication data frames in the first frequency band and the second frequency band, performs frame matching on the communication data frames in the first frequency band and the second frequency band, and obtains multiple pairs of communication data frames.
[0082] When the receiving device receives a communication data frame in the mmWave band, it obtains the transmission timestamp of the communication data frame through frame decoding. Similarly, when it receives a communication data frame in the Sub-7GHz band, it obtains the transmission timestamp of the communication data frame through frame decoding. Then, it can perform frame matching on the communication data frames in these two frequency bands based on their transmission timestamps to obtain multiple pairs of communication data frames.
[0083] In some embodiments, communication data frames in the mmWave band and Sub-7GHz band whose transmission timestamps differ within a preset range can be considered as a pair of communication data frames.
[0084] In some embodiments, the two communication data frames with the closest transmission timestamps in the mmWave band and Sub-7GHz band can be regarded as a pair of communication data frames.
[0085] For example, Figure 5 An mmWave frequency band is shown ( Figure 5 The first frequency band in the middle) and the Sub-7GHz band ( Figure 5 Multiple pairs of communication data frames are formed by matching communication data frames under the second frequency band (in the second frequency band). For example, if the time difference between the first communication data frame under the mmWave frequency band and the second communication data frame under the Sub-7GHz frequency band is within a preset range, or if the transmission timestamps of the first and second communication data frames are closest, then the first and second communication data frames are a pair of communication data frames.
[0086] It should be noted that steps 402 to 406 of this application can be performed by the receiving device, the transmitting device, or a third-party device; that is, any of these three types of devices can serve as a sensing device. If performed by a third-party device, it does not affect the process of the transmitting device sending communication data frames in both frequency bands to the receiving device; it is essentially a process of copying the communication data frames in both frequency bands for third-party processing. The following embodiments of this application are all described using a receiving device as an example.
[0087] 403. The receiving device extracts the signal propagation state information corresponding to each pair of communication data frames and determines the signal propagation state matching relationship of the same target in each pair of communication data frames.
[0088] After determining each pair of communication data frames, the receiving device can match the signal propagation state information carried in the first communication data frame and the signal propagation state information carried in the second communication data frame in each pair of communication data frames to determine the signal propagation state matching relationship of the same target in each pair of communication data frames.
[0089] This is because in a Wi-Fi environment between a transmitting device and a receiving device, there may be multiple targets. After identifying multiple pairs of communication data frames, signals for the first frequency band and the second frequency band can be directed to the same target during propagation, thereby determining the signal propagation status information of the same target in the mmWave frequency band and the Sub-7GHz frequency band.
[0090] The target in this application can be understood as an object or human body, that is, the object or human body that the signals of the first frequency band and the second frequency band come into contact with during the propagation process.
[0091] For example, Figure 6 The diagram shows the distance information of two targets in the Sub-7GHz band and the mmWave band. The distance resolution in the Sub-7GHz band is relatively coarse, for example, each scale mark is 47cm, while the distance resolution in the mmWave band is finer, for example, each scale mark is 1.74cm. Figure 6 In the diagram, the horizontal axis represents range information, and the vertical axis represents power. Assuming target 1 has the range information shown by curve 60 in the Sub-7GHz band and curve 61 in the mmWave band, the range information for target 1 differs between the two bands. The range information in the mmWave band is more refined. The range information shown by curves 60 and 61 matches, indicating the same target 1. Target 2 is similar to target 1.
[0092] In some embodiments, the signal propagation state information is the propagation path length. The propagation path length can be understood as the sum of the distance from the transmitting device to the target and the distance from the target to the receiving device. For example... Figure 7 The diagram shows multipath information between a person and a transmitting device 70 and a receiving device 71. If the distance information from the transmitting device 70 to the person is L1 and the distance information from the person to the receiving device 71 is L2 in a certain frequency band, the propagation path length can be expressed as L1+L2.
[0093] For example, for each pair of communication data frames, the receiving device 71 can parse the first communication data frame in the mmWave band to obtain a first CSI, the first CSI including a first propagation path length carried by the first communication data frame; and parse the second communication data frame in the Sub-7GHz band to obtain a second CSI, the second CSI including a second propagation path length carried by the second communication data frame. The first and second propagation path lengths are matched to determine the propagation path length matching relationship of the same target in each pair of communication data frames in the mmWave band and the Sub-7GHz band.
[0094] In some embodiments, the signal propagation state information is the distance information between the target and the sensing device. The sensing device here is, for example, a transmitting device. Figure 8 The diagram illustrates the distance information between a person and the transmitting device 80 when the person is between the transmitting device 80 and the receiving device 81. This distance information can be understood as the distance information L3 between the transmitting device 80 and the person, obtained when a communication data frame sent by the transmitting device 80 arrives at the person and is reflected back to the transmitting device 80. For example, this distance information L3 can be obtained through a radar device in the transmitting device 80.
[0095] For example, for each pair of communication data frames, the transmitting device can parse the first communication data frame in the mmWave band to obtain first distance information, and parse the second communication data frame in the Sub-7GHz band to obtain second distance information. The transmitting device matches the first distance information and the second distance information to determine the distance information matching relationship of the same target in each pair of communication data frames.
[0096] Since the bandwidths of the mmWave and Sub-7GHz bands are known information specified by the standard, the signal propagation status information of communication data frames in the two bands can be matched based on formula (1). However, since the distance resolution of the mmWave band is better than that of the Sub-7GHz band, the same signal propagation status information may be reflected as a value with a larger error in the Sub-7GHz band.
[0097] 404. The receiving device targets the same target and obtains the phase change information between communication data frames in the second frequency band.
[0098] While the mmWave band offers high range resolution, it is prone to phase ambiguity, meaning it has poor resistance to phase ambiguity. Therefore, the Sub-7GHz band can be chosen to acquire phase change information between continuous communication data frames. Since the signal propagation state has already been matched in step 403, the same target can be identified in the high-resolution range information under the mmWave band based on the signal propagation state, such as the matching relationship of range information. The same target under the mmWave band is then matched to the range information corresponding to the communication data frame under the Sub-7GHz band to extract the phase information of the same target under the Sub-7GHz band in consecutive communication data frames, thereby obtaining the phase change information of the same target under the Sub-7GHz band. Because the wavelength of the Sub-7GHz band is longer, the extracted phase change information... It has better anti-phase blurring performance.
[0099] 405. The receiving device, targeting the same target, obtains the first phase change information between adjacent communication data frames in multiple communication data frames of the first frequency band based on the phase change information between communication data frames in the second frequency band.
[0100] Although the phase change information of the same target in the Sub-7GHz band obtained in step 404 While it exhibits good anti-phase ambiguity performance, its accuracy is poor when directly used for motion information estimation. This application can utilize phase information from multiple pairs of communication data frames matched in step 402 within the mmWave band to... Optimization can be performed by adjusting the wavelength and the inter-frame spacing of the communication data frames. The conversion is performed to obtain the first phase change information between adjacent communication data frames in multiple communication data frames under the mmWave frequency band frame.
[0101] In other words, this application can obtain the first phase change information between adjacent communication data frames in multiple communication data frames of the first frequency band when the signals of the first frequency band and the second frequency band come into contact with the same target during the propagation process.
[0102] The first phase change information between adjacent communication data frames in the first frequency band is calculated based on the phase change information between adjacent communication data frames in the second frequency band, the time interval between adjacent communication data frames in the first frequency band, and the time interval between adjacent communication data frames in the second frequency band.
[0103] For example, such as Figure 9 The diagram shows the time interval between communication data frames in the first and second frequency bands. In the first frequency band, adjacent communication data frames include the third and fourth communication data frames; in the second frequency band, adjacent communication data frames include the fifth and sixth communication data frames. The third and fifth communication data frames are one pair of multiple pairs of communication data frames, and the fourth and sixth communication data frames are also one pair of multiple pairs of communication data frames. The calculation method for the first phase change information between the third and fourth communication data frames is as shown in formula (5).
[0104] Formula (5) in, This indicates the first phase change information between the third and fourth communication data frames. This indicates the phase change information between the fifth and sixth communication data frames. This represents the time interval between the timestamps of the third and fourth communication data frames. This indicates the time interval between the timestamps of the fifth and sixth communication data frames. This indicates the subcarrier wavelength in the first frequency band. This indicates the subcarrier wavelength in the second frequency band.
[0105] For example, taking the first frequency band as the mmWave band and the second frequency band as the Sub-7GHz band, the receiving device can use the phase change information between communication data frames in the Sub-7GHz band as an example. carrier wavelength of mmWave band Carrier wavelength in the Sub-7GHz band Inter-frame time interval of communication data in the mmWave band and the time interval between communication data frames in the Sub-7GHz band Phase change information between communication data frames in the Sub-7GHz band First phase change information converted to mmWave band communication data frames . The calculation method is shown in formula (6).
[0106] Formula (6) In this way, the phase change information of the same target in the Sub-7GHz band Phase change information converted to mmWave band This means that for each pair of communication data frames, the high phase ambiguity resistance of the Sub-7GHz band is combined with the high distance resolution and high precision micro-motion detection of the mmWave band, thereby improving the sensing performance of Wi-Fi signals.
[0107] The above step 405 is obtained through conversion. It is still significantly affected by phase noise, and the calculated value is usually... The difference between the phase difference between the actual detected communication data frames and the phase difference between the two in the mmWave band is In order to remove as many integer multiples as possible from the converted values, To reduce phase noise, this application can further utilize high-precision raw phase information from consecutive communication data frames corresponding to the mmWave frequency band. Optimize.
[0108] Therefore, the sensing method of this application may also include step 406.
[0109] 406. For the same target encountered during the propagation of signals in the first and second frequency bands, the receiving device determines second phase change information between adjacent communication data frames in the first frequency band based on first phase change information between adjacent communication data frames in the first frequency band. The second phase change information is calculated based on the relationship between the original phase change information and coefficients between adjacent communication data frames in the first frequency band.
[0110] The coefficient is used to indicate that the phase difference between the second phase change information and the original phase change information is an integer multiple of 2π, where π is the constant of pi.
[0111] Specifically, given the possibility of phase ambiguity, the original phase information between any two communication data frames in the first frequency band is known. and The phase difference can be expressed as shown in formula (7).
[0112] Formula (7) in, This indicates a modulo division operation.
[0113] In this way, It can be represented as shown in formula (8).
[0114] Formula (8) Ideally, the coefficient k should be an integer. However, due to... Including phase noise, the actual coefficient k may contain decimal places. Therefore, the noise can be filtered out by rounding the coefficient k to the nearest integer.
[0115] Therefore, based on the first phase change information between any two communication data frames in the first frequency band, such as the first phase change information between the third and fourth communication data frames mentioned above, the coefficients... It can be represented as shown in formula (9).
[0116] Formula (9) in, This indicates the rounding operation. This represents the optimized coefficients. This represents the phase difference between any two communication data frames in the first frequency band, such as the original phase information of the third communication data frame and the original phase information of the fourth communication data frame, where n is an integer.
[0117] In this way, after optimizing the coefficient k, we obtain After optimization, the second phase change information between any two communication data frames in the first frequency band can be shown in formula (10).
[0118] Formula (10) Taking the first frequency band as mmWave and the second frequency band as Sub-7GHz as an example, the above formula (7) can be transformed as shown in formula (11).
[0119] Formula (11) This represents the phase difference between the original phase information of any two communication data frames in the mmWave band.
[0120] The above formula (9) can be transformed as shown in formula (12).
[0121] Formula (12) Therefore, the second phase change information between any two communication data frames in the mmWave band can be expressed as shown in formula (13).
[0122] (13) Therefore, based on Calculating the target's motion information can retain the advantage of the mmWave band in high-precision detection of minute movements.
[0123] This application can improve the sensing performance of Wi-Fi signals by matching the transmission timestamps of communication data frames in the Sub-7GHz band and the mmWave band. The high anti-ambiguity performance of the Sub-7GHz band can be transferred to the mmWave band. The phase change information between communication data frames in the mmWave band can be used to infer the motion information of the target. This combines the strong phase ambiguity resistance of the Sub-7GHz band with the high distance resolution and high precision micro-motion detection of the mmWave band.
[0124] It should be noted that although the above embodiments of this application are described by matching the transmission times of communication data frames in the two frequency bands received by the receiving device, they are not limited to this. This application can also achieve a similar effect to a certain extent by calculating the reception times of communication data frames in the two frequency bands using the receiving device.
[0125] It is understood that, in order to achieve the above functions, the sensing device includes hardware and / or software modules that perform the respective functions. Based on the algorithmic steps of the examples described in conjunction with the embodiments disclosed herein, this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed in hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application in conjunction with the embodiments, but such implementation should not be considered beyond the scope of this application.
[0126] This embodiment can divide the sensing device into functional modules according to the above method example. For example, each function can be divided into its own functional modules, or two or more functions can be integrated into one processing module. The integrated modules can be implemented in hardware. It should be noted that the module division in this embodiment is illustrative and only represents one logical functional division; other division methods may be used in actual implementation.
[0127] When dividing each function into modules according to its corresponding function. Figure 10 A schematic diagram of a possible composition of the sensing device 100 involved in the above embodiments is shown, such as... Figure 10 As shown, the sensing device 100 may include: a receiving unit 1001, a data frame matching unit 1002, and a phase acquisition unit 1003.
[0128] The receiving unit 1001 can be used to support the sensing device 100 in performing the above steps 301, 401, etc., and / or other processes used in the technology described herein.
[0129] The data frame matching unit 1002 can be used to support the sensing device 100 in performing the above steps 302, 402, 403, etc., and / or other processes used in the technology described herein.
[0130] The phase acquisition unit 1003 can be used to support the sensing device 100 in performing the above steps 404, 405 and 406, and / or other processes used in the technology described herein.
[0131] It should be noted that all relevant content of each step involved in the above method embodiments can be referenced from the functional description of the corresponding functional module, and will not be repeated here.
[0132] The sensing device 100 provided in this embodiment is used to execute the above-described sensing method, and therefore can achieve the same effect as the above-described implementation method.
[0133] When using integrated units, the sensing device 100 may include a processing module, a storage module, and a communication module. The processing module can be used to control and manage the operations of the sensing device 100, for example, to support the sensing device 100 in executing the steps performed by the data frame matching unit 1002 and the phase acquisition unit 1003. The storage module can be used to support the sensing device 100 in storing program code and data, such as storing phase change information between communication data frames. The communication module can be used to support communication between the sensing device 100 and other devices, such as communication with a transmitting device that sends communication data frames or a receiving device that receives communication data frames.
[0134] The processing module can be a processor or a controller. It can implement or execute various exemplary logic blocks, modules, and circuits described in conjunction with the disclosure of this application. The processor can also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of digital signal processing (DSP) and a microprocessor, etc. The storage module can be a memory. The communication module can specifically be a radio frequency circuit, a Bluetooth chip, a Wi-Fi chip, or other devices that interact with other electronic devices.
[0135] In one embodiment, when the processing module is a processor, the storage module is a memory, and the transceiver module is a transceiver, the sensing device involved in this embodiment can be a device with... Figure 11 The sensing device shown has the following structure.
[0136] This application also provides an electronic device, including one or more processors and one or more memories. The one or more memories are coupled to the one or more processors, and the one or more memories are used to store computer program code, including computer instructions. When the one or more processors execute the computer instructions, the electronic device performs the aforementioned method steps to implement the sensing method in the above embodiments.
[0137] Embodiments of this application also provide a computer storage medium storing computer instructions. When the computer instructions are executed on an electronic device, the electronic device performs the aforementioned method steps to implement the sensing method in the above embodiments.
[0138] Embodiments of this application also provide a computer program product that, when run on a computer, causes the computer to perform the aforementioned related steps to implement the sensing method executed by the electronic device in the above embodiments.
[0139] In addition, embodiments of this application also provide an apparatus, which may specifically be a chip, component or module. The apparatus may include a connected processor and a memory. The memory is used to store computer execution instructions. When the apparatus is running, the processor can execute the computer execution instructions stored in the memory to cause the chip to execute the sensing methods executed by the electronic devices in the above-described method embodiments.
[0140] In this embodiment, the sensing device, computer storage medium, computer program product or chip are all used to execute the corresponding methods provided above. Therefore, the beneficial effects that can be achieved can be referred to the beneficial effects of the corresponding methods provided above, and will not be repeated here.
[0141] Another embodiment of this application provides a system that may include the above-described transmitting device and receiving device, and can be used to implement the above-described sensing method.
[0142] Through the above description of the embodiments, those skilled in the art will understand that, for the sake of convenience and brevity, only the division of the above functional modules is used as an example. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.
[0143] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another device, or some features may be ignored or not executed. Furthermore, the mutual coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.
[0144] The units described as separate components may or may not be physically separate. A component shown as a unit can be one or more physical units; that is, it can be located in one place or distributed in multiple different locations. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.
[0145] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.
[0146] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a readable storage medium. Based on this understanding, the technical solutions of the embodiments of this application, essentially or in other words, the parts that contribute to the prior art, or all or part of the technical solutions, can be embodied in the form of a software product. This software product is stored in a storage medium and includes several instructions to cause a device (which may be a microcontroller, chip, etc.) or processor to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.
[0147] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.
Claims
1. A sensing method, characterized in that, Simultaneously employing a first frequency band and a second frequency band for sensing, wherein the frequency of the first frequency band is higher than the frequency of the second frequency band, the method includes: Receive multiple communication data frames from the first frequency band and multiple communication data frames from the second frequency band; Multiple pairs of communication data frames are acquired, each pair of communication data frames including a first communication data frame from multiple communication data frames in the first frequency band and a second communication data frame from multiple communication data frames in the second frequency band.
2. The method according to claim 1, characterized in that, The first communication data frame includes a first timestamp, which is the sending timestamp of the first communication data frame; The second communication data frame includes a second timestamp, which is the time stamp of the second communication data frame being sent.
3. The method according to claim 1 or 2, characterized in that, The method further includes: For the same target encountered by signals from the first frequency band and the second frequency band during propagation, first phase change information between adjacent communication data frames in multiple communication data frames of the first frequency band is obtained; The first phase change information between adjacent communication data frames in the multiple communication data frames of the first frequency band is calculated based on the phase change information between adjacent communication data frames in the multiple communication data frames of the second frequency band, the time interval between adjacent communication data frames in the multiple communication data frames of the first frequency band, and the time interval between adjacent communication data frames in the multiple communication data frames of the second frequency band.
4. The method according to claim 3, characterized in that, The adjacent communication data frames in the multiple communication data frames of the first frequency band include a third communication data frame and a fourth communication data frame; the adjacent communication data frames in the multiple communication data frames of the second frequency band include a fifth communication data frame and a sixth communication data frame; the third communication data frame and the fifth communication data frame are one pair of communication data frames in the multiple pairs of communication data frames; the fourth communication data frame and the sixth communication data frame are one pair of communication data frames in the multiple pairs of communication data frames. The calculation method for the first phase change information between the third communication data frame and the fourth communication data frame includes: in, This indicates the first phase change information between the third and fourth communication data frames. This indicates the phase change information between the fifth and sixth communication data frames. This represents the time interval between the timestamp of the third communication data frame and the timestamp of the fourth communication data frame. This represents the time interval between the timestamp of the fifth communication data frame and the timestamp of the sixth communication data frame. This indicates the subcarrier wavelength in the first frequency band. This indicates the subcarrier wavelength in the second frequency band.
5. The method according to claim 4, characterized in that, The method further includes: For the same target encountered by signals from the first frequency band and the second frequency band during propagation, the second phase change information between adjacent communication data frames in the multiple communication data frames of the first frequency band is determined based on the first phase change information between adjacent communication data frames in the multiple communication data frames of the first frequency band. The second phase change information is calculated based on the relationship between the original phase change information and coefficients between adjacent communication data frames in the first frequency band. The coefficient is used to indicate that the phase difference between the second phase change information and the original phase change information is an integer multiple of 2π, where π is the constant of pi.
6. The method according to claim 5, characterized in that, Based on the first phase change information between the third and fourth communication data frames, the coefficient is expressed as: in, Represents the coefficient, This represents the phase difference between the original phase information of the third communication data frame and the original phase information of the fourth communication data frame, where n is an integer and round() represents the rounding operation.
7. The method according to any one of claims 1-6, characterized in that, The first frequency band is the mmWave band, and the second frequency band is the Sub-7GHz band.
8. A communication device, characterized in that, The device includes at least one processor connected to a memory, the at least one processor being configured to read and execute a program stored in the memory, such that the communication device performs the method as described in any one of claims 1-7.
9. A chip, characterized in that, The chip is coupled to a memory, and the chip is used to read and execute program instructions stored in the memory so that a communication device including the chip performs the method as described in any one of claims 1-7.
10. A computer-readable storage medium, characterized in that, Includes computer instructions that, when executed on an electronic device, cause the electronic device to perform the method as described in any one of claims 1-7.