Bluetooth direction-finding method, terminal device electronic device, and storage medium

Abstract

This application relates to a Bluetooth direction finding method, terminal device, electronic device, and storage medium, belonging to the field of Bluetooth positioning technology. The Bluetooth direction finding method includes: acquiring phase information of Bluetooth signals received by each antenna in a Bluetooth antenna array at different times; determining multiple phase differences between adjacent antennas in the Bluetooth antenna array based on the phase information; determining whether the amplitude of signal interference to the Bluetooth signal is within a preset amplitude range; if the amplitude of signal interference to the Bluetooth signal is within the preset amplitude range, determining the angle of arrival (Angle of Arrival) of the Bluetooth signal based on the multiple phase differences, the wavelength of the Bluetooth signal, and the spacing between adjacent antennas. This application, when calculating the Angle of Arrival, only selects the phase information of Bluetooth signals whose amplitude of signal interference is within the preset amplitude range for calculation, thereby improving the accuracy of the calculation results and thus improving positioning accuracy.

Description

Technical Field

[0001] This application belongs to the field of Bluetooth positioning technology, specifically relating to a Bluetooth direction finding method, terminal device, electronic device, and storage medium. Background Technology

[0002] Bluetooth, as a wireless communication technology, has been widely used in various fields. In early 2019, the Bluetooth Special Interest Group (SIG) officially released the Bluetooth 5.1 standard, adding high-precision Bluetooth direction-finding technology. Bluetooth direction-finding technology is mainly achieved by calculating the Angle of Arrival (AOA) of the Bluetooth signal. When a Bluetooth signal propagates, the different transmission distances between different Bluetooth antennas result in a phase difference in the measured Bluetooth signal. Using this phase difference, combined with the antenna array structure, the angle of arrival of the Bluetooth signal is calculated.

[0003] Traditional methods for calculating the angle of arrival include MUSIC (Multiple Signal Classification) and ESPRIT (Estimating Signal Parameters via Rotational Invariance Techniques). These algorithms heavily rely on the accuracy of signal transmission, and their positioning accuracy will drop sharply when there is noise interference in the signal. Summary of the Invention

[0004] Therefore, the purpose of this application is to provide a Bluetooth direction finding method, terminal device, electronic device and storage medium to improve the problem of inaccurate positioning accuracy caused by the inaccurate angle of arrival determined by the existing calculation method.

[0005] The embodiment of the present application is implemented as follows:

[0006] In a first aspect, embodiments of this application provide a Bluetooth direction finding method, comprising: acquiring phase information of Bluetooth signals received by each antenna in a Bluetooth antenna array at different times; determining multiple phase differences between adjacent antennas in the Bluetooth antenna array based on the phase information; determining whether the amplitude of signal interference to the Bluetooth signal is within a preset amplitude range; if the amplitude of signal interference to the Bluetooth signal is within the preset amplitude range, determining the angle of arrival of the Bluetooth signal based on the multiple phase differences, the wavelength of the Bluetooth signal, and the spacing between adjacent antennas.

[0007] In this embodiment of the application, after obtaining multiple phase differences, it is also determined whether the amplitude of the Bluetooth signal being interfered with is within a preset amplitude range. Only when the amplitude of the Bluetooth signal being interfered with is within the preset amplitude range will subsequent calculations be performed. By selecting only the phase information of the Bluetooth signal whose amplitude of interference is within the preset amplitude range to calculate the angle of arrival, the accuracy of the calculation results can be improved, thereby improving the positioning accuracy.

[0008] In one possible implementation of the first aspect embodiment, determining multiple phase differences between adjacent antennas in the Bluetooth antenna array based on the phase information includes: for any adjacent antenna in the Bluetooth antenna array, determining the phase difference between the adjacent antennas based on the phase information of Bluetooth signals received by one of the adjacent antennas in two consecutive receptions and the phase information of Bluetooth signals received by the other of the adjacent antennas in a previous reception.

[0009] In this embodiment of the application, for any adjacent antenna, the phase information of the Bluetooth signals received by one of the adjacent antennas in two consecutive steps (which can be used) is determined. (This is an example of calculating the phase difference between two Bluetooth signals received from the same antenna, as shown below). This is to compensate for the phase difference of Bluetooth signals received by different antennas in the same instance. This allows for the rapid and accurate determination of the phase difference between different adjacent antennas.

[0010] In one possible implementation of the first aspect embodiment, determining whether the amplitude of signal interference to the Bluetooth signal is within a preset amplitude range includes: determining a parameter value characterizing the amplitude of signal interference to the Bluetooth signal based on the plurality of phase differences, wherein the parameter value is the variance, mean, or standard deviation of the plurality of phase differences; determining whether the amplitude of signal interference to the Bluetooth signal is within the preset amplitude range by comparing the parameter value with a corresponding preset threshold; wherein, if the parameter value is less than the preset threshold, it indicates that the amplitude of signal interference to the Bluetooth signal is within the preset amplitude range.

[0011] In this embodiment, by comparing the variance, mean, or standard deviation of multiple phase differences with the corresponding preset threshold, it is determined whether the amplitude of signal interference on the Bluetooth signal is within the preset amplitude range, so as to remove low-quality data and improve the accuracy of the calculation results. At the same time, by calculating the variance, mean, or standard deviation of multiple phase differences, the influence of small signal fluctuations can be eliminated.

[0012] In one possible implementation of the first aspect embodiment, the preset threshold is determined in advance by a plurality of first phase differences determined based on the phase information of the first standard Bluetooth signal received by each antenna at different times and a plurality of second phase differences determined based on the phase information of the second standard Bluetooth signal received by each antenna at different times.

[0013] In this embodiment, a preset threshold is determined based on multiple first phase differences determined by the phase information of the first standard Bluetooth signal (such as a Bluetooth signal with less interference, wherein the magnitude of interference can be determined by the difference between the angle of arrival actually measured during the test phase and the angle of arrival determined according to the method shown in this application; if the difference is less than a certain precision, it is considered that the interference is less, otherwise it is considered that the interference is greater, and the precision can be reasonably set as needed) received by each antenna at different times, and multiple second phase differences determined by the phase information of the second standard Bluetooth signal (such as a Bluetooth signal with greater interference) received by each antenna at different times. The preset threshold determined in this way can more realistically reflect the magnitude of signal interference to the Bluetooth signal and is more practical.

[0014] In one possible implementation of the first aspect embodiment, determining the angle of arrival of the Bluetooth signal based on the plurality of phase differences, the wavelength of the Bluetooth signal, and the spacing between adjacent antennas includes: determining the product of the mean of the plurality of phase differences and the quotient of the wavelength of the Bluetooth signal and the spacing between adjacent antennas; and fitting the product using a polynomial fitting algorithm to determine the angle of arrival.

[0015] In this embodiment, a polynomial fitting algorithm, such as the 5th order Taylor polynomial algorithm, is used to fit the product to determine the angle of arrival. The polynomial fitting calculation greatly reduces the amount of computation while ensuring the accuracy of data calculation.

[0016] In one possible implementation of the first aspect embodiment, after determining the angle of arrival of the Bluetooth signal based on the plurality of phase differences, the wavelength of the Bluetooth signal, and the spacing between adjacent antennas, the method further includes: determining a final angle of arrival based on the plurality of angles of arrival determined over a period of time.

[0017] In this embodiment of the application, the final angle of arrival is determined based on multiple angles of arrival determined over a period of time, thereby improving the stability of the angle calculation results.

[0018] In one possible implementation of the first aspect embodiment, determining the final angle of arrival based on multiple angles of arrival determined over a period of time includes: filtering the multiple angles of arrival determined over a period of time using a median mean filtering algorithm to obtain the final angle of arrival.

[0019] In this embodiment, a median mean filtering algorithm is used to filter multiple angles of arrival determined over a period of time to obtain the final angle of arrival. Specifically, the maximum and minimum values ​​among the multiple angles of arrival determined over a period of time are filtered out, and then the average (mean) of the remaining angles of arrival is taken to obtain the final angle of arrival, thereby improving the stability and accuracy of the angle calculation results.

[0020] In one possible implementation of the first aspect embodiment, obtaining the phase information of the Bluetooth signal received by each antenna in the Bluetooth antenna array at different times includes: performing IQ (I stands for in-phase, Q stands for quadrature, and the phase difference from I is 90°) sampling on the Bluetooth signal received by each antenna in the Bluetooth antenna array at different times, and determining the corresponding phase information based on the IQ sampling values.

[0021] In a possible implementation of the first aspect embodiment, after determining whether the amplitude of the Bluetooth signal being interfered with is within a preset amplitude range, the method further includes: if the amplitude of the Bluetooth signal being interfered with is not within the preset amplitude range, then re-acquiring the phase information of the Bluetooth signals received by each antenna in the Bluetooth antenna array at different times.

[0022] In this embodiment, only the phase information of Bluetooth signals whose amplitude of signal interference is within a preset range is selected to calculate the angle of arrival, thereby improving the accuracy of the calculation results and thus improving the positioning accuracy.

[0023] Secondly, embodiments of this application also provide a terminal device, including: a Bluetooth module and a processor; the Bluetooth module includes a Bluetooth antenna array and a Bluetooth chip; the Bluetooth chip is used to perform IQ sampling on the Bluetooth signals received by each antenna in the Bluetooth antenna array at different times, and determine the corresponding phase information based on the IQ sampling values; the processor is used to obtain the phase information of the Bluetooth signals received by each antenna in the Bluetooth antenna array at different times from the Bluetooth module, determine multiple phase differences between each adjacent antenna in the Bluetooth antenna array based on the phase information, and determine whether the amplitude of the Bluetooth signal being interfered with is within a preset amplitude range; if the amplitude of the Bluetooth signal being interfered with is within the preset amplitude range, determine the angle of arrival of the Bluetooth signal based on the multiple phase differences, the wavelength of the Bluetooth signal and the spacing between adjacent antennas.

[0024] Thirdly, embodiments of this application also provide an electronic device, including: a memory and a processor, the processor being connected to the memory; the memory being used to store a program; the processor being used to invoke the program stored in the memory to execute the method provided by any possible implementation of the first aspect embodiment and / or in combination with the first aspect embodiment.

[0025] Fourthly, embodiments of this application also provide a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, performs the method provided by any possible implementation of the first aspect embodiments and / or in combination with the first aspect embodiments.

[0026] Other features and advantages of this application will be set forth in the following description. The objectives and other advantages of this application can be realized and obtained through the structures specifically pointed out in the written description and the accompanying drawings. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. The above and other objects, features, and advantages of this application will become clearer through the drawings. The same reference numerals indicate the same parts in all the drawings. The drawings are not intentionally drawn to scale to actual size; the focus is on illustrating the main points of this application.

[0028] Figure 1 A schematic flowchart of a Bluetooth direction finding method provided in an embodiment of this application is shown.

[0029] Figure 2 This illustration shows a schematic diagram of a Bluetooth direction finding method provided in an embodiment of this application.

[0030] Figure 3 A schematic diagram of the structure of an electronic device provided in an embodiment of this application is shown.

[0031] Figure 4 A schematic diagram of the structure of an electronic device provided in an embodiment of this application is shown. Detailed Implementation

[0032] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application.

[0033] It should be noted that similar numbers and letters represent similar items in the following figures, so once an item is defined in one figure, it does not need to be further defined and explained in the subsequent figures. At the same time, in the description of this application, relational terms such as "first", "second", etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements includes not only those elements, but also includes other elements that are not clearly listed, or also includes elements inherent to such process, method, article or equipment. In the absence of more restrictions, the elements defined by the sentence "comprise a..." do not exclude the presence of other identical elements in the process, method, article or equipment including the elements.

[0034] Furthermore, the term "and / or" in this application is merely a description of the association relationship between associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone.

[0035] Given the inaccuracy of the angle of arrival determined by existing calculation methods, which leads to inaccurate positioning accuracy, the reason is that Bluetooth operates in the ISM (Industrial, Scientific and Medical) band (mainly open to the three major institutions of industry, science and medicine), which is easily interfered with by other signals. This results in unstable Bluetooth signals, leading to low accuracy of the calculated results and large angle fluctuations, thus causing inaccurate positioning accuracy.

[0036] Based on this, embodiments of this application provide a Bluetooth direction finding method to improve the problem of inaccurate positioning accuracy caused by inaccurate angle of arrival determined by existing calculation methods. The following will combine... Figure 1 The Bluetooth direction finding method provided in the embodiments of this application will be described.

[0037] S1: Obtain the phase information of the Bluetooth signals received by each antenna in the Bluetooth antenna array at different times.

[0038] When it is necessary to determine the angle of arrival, obtain the phase information of the Bluetooth signals received by each antenna in the Bluetooth antenna array at different times.

[0039] Among them, obtaining the phase information of the Bluetooth signal received by each antenna in the Bluetooth antenna array at different times can be done by directly obtaining the phase information of the Bluetooth signal received by each antenna in the Bluetooth antenna array at different times from the disk or database. That is, this process can be non-real-time. After obtaining the phase information of the Bluetooth signal received by each antenna in the Bluetooth antenna array at different times in advance, it can be stored and then directly retrieved when needed.

[0040] In one optional implementation, the phase information of the Bluetooth signals received by each antenna in the Bluetooth antenna array at different times can be obtained, or it can be obtained in real time. The process can be to perform IQ sampling (I stands for in-phase, Q stands for quadrature, and the phase difference from I is 90°) on the CTE signal (i.e., the fixed-frequency unmodulated signal, which is a part of the Bluetooth signal) in the Bluetooth signals received by each antenna in the Bluetooth antenna array at different times, and determine the corresponding phase information based on the IQ sampling values.

[0041] The formula for determining the corresponding phase information based on the IQ sample values ​​is as follows:

[0042] In this formula, I represents the x-coordinate of the point obtained by IQ sampling of the CTE signal in the Bluetooth signal in the IQ coordinate system, and Q represents the y-coordinate of the point obtained by IQ sampling of the CTE signal in the Bluetooth signal in the IQ coordinate system.

[0043] During IQ sampling, the Bluetooth signals received by each antenna in the Bluetooth antenna array at different times are sampled using IQ sampling to obtain multiple phase information values ​​(usually 10 to 50). Each pair of IQ values ​​corresponds to one phase information value, thus allowing the acquisition of the phase information of the Bluetooth signals received by each antenna at different times.

[0044] When it is necessary to obtain the phase information of the Bluetooth signal received by each antenna in the Bluetooth antenna array at different times, the corresponding phase can be obtained by switching different antennas to receive Bluetooth signals and then performing IQ sampling on the Bluetooth signals received by each antenna at different times.

[0045] To better understand, let's take a Bluetooth antenna array with two antennas (antenna A and antenna B) as an example. First, we switch antenna A to receive Bluetooth signals. We then perform IQ sampling on the Bluetooth signal received by antenna A for the first time to obtain the corresponding phase. Then, antenna B is switched to receive Bluetooth signals. The first Bluetooth signal received by antenna B is sampled using IQ sampling to obtain the corresponding phase. Then, antenna A is switched to receive Bluetooth signals. The IQ sampling of the Bluetooth signal received by antenna A a second time is performed to obtain the corresponding phase. Then, antenna B is switched to receive Bluetooth signals. The Bluetooth signal received by antenna B a second time is sampled using IQ sampling to obtain the corresponding phase. Similarly, by switching different antennas to receive Bluetooth signals, and then performing IQ sampling on the Bluetooth signals received by each antenna at different times, multiple phase information (usually 10 to 50) can be obtained. These phase information can form a phase sequence (containing 10 to 50 phase information).

[0046] For example, taking a Bluetooth antenna array containing three antennas (antenna A, antenna B, and antenna C), first switch antenna A to receive Bluetooth signals. Then, perform IQ sampling on the Bluetooth signal received by antenna A for the first time to obtain the corresponding phase. Then, antenna B is switched to receive Bluetooth signals. The IQ sampling of the Bluetooth signal received by antenna B for the first time is performed to obtain the corresponding phase. Then, antenna C is switched to receive Bluetooth signals. The IQ sampling of the Bluetooth signal received by antenna C for the first time is performed to obtain the corresponding phase. Then, antenna A is switched to receive Bluetooth signals. The IQ sampling of the Bluetooth signal received by antenna A a second time is performed to obtain the corresponding phase. Then, antenna B is switched to receive Bluetooth signals. The Bluetooth signal received by antenna B a second time is sampled using IQ sampling to obtain the corresponding phase. Then, antenna C is switched to receive Bluetooth signals. The Bluetooth signal received by antenna C a second time is sampled using IQ sampling to obtain the corresponding phase. Similarly, by switching different antennas to receive Bluetooth signals, and then performing IQ sampling on the Bluetooth signals received by each antenna at different times, multiple phase information (usually 10 to 50) can be obtained. These phase information can form a phase sequence (containing 10 to 50 phase information).

[0047] It is understandable that the number of antennas in a Bluetooth antenna array is not limited to the two or three antennas in the example above. For Bluetooth antenna arrays containing more antennas, the principle of obtaining the phase information of the Bluetooth signal received by each antenna in the Bluetooth antenna array at different times is the same as the principle in the example above.

[0048] S2: Determine multiple phase differences between each adjacent antenna in the Bluetooth antenna array based on the phase information.

[0049] After obtaining the phase information of the Bluetooth signals received by each antenna in the Bluetooth antenna array at different times, the phase difference between each adjacent antenna in the Bluetooth antenna array can be determined based on this phase information, thus obtaining multiple phase differences.

[0050] In one optional implementation, the process of determining multiple phase differences between adjacent antennas in a Bluetooth antenna array based on this phase information can be as follows: For any adjacent antenna in the Bluetooth antenna array, the phase difference between the adjacent antennas is determined based on the phase information of the Bluetooth signals received by one of the adjacent antennas in two consecutive (previous and subsequent) moments, and the phase information of the Bluetooth signal received by the other antenna in the adjacent antenna in a previous moment. This is achieved by calculating the phase difference between the Bluetooth signals received by the same antenna in two consecutive moments, such as... This is to compensate for the phase difference of Bluetooth signals received by different antennas in the same transmission, such as This allows us to obtain the desired phase difference between different adjacent antennas.

[0051] The formula for calculating the phase difference between adjacent antennas is as follows:

[0052] This represents the phase difference between adjacent antennas 1 and 2. This indicates the phase information of the Bluetooth signal previously received by antenna 2. This indicates the phase information of the Bluetooth signal previously received by antenna 1. This represents the phase information of the Bluetooth signal received by antenna 1 in the next iteration, and n represents the total number of antennas in the Bluetooth antenna array.

[0053] To better understand, let's take the two antennas (antenna A and antenna B) from the example above as an example. This indicates the phase information of the Bluetooth signal received by antenna A for the first time. This indicates the phase information of the Bluetooth signal received by antenna B for the first time. This indicates the phase information of the Bluetooth signal received by antenna A for the second time. This represents the phase information of the Bluetooth signal received by antenna B for the second time. Similarly, assuming there are 20 phase information points, we can obtain 9 phase differences. Therefore, the 9 phase differences between antenna A and antenna B are as follows:

[0054]

[0055]

[0056]

[0057]

[0058]

[0059]

[0060]

[0061]

[0062]

[0063] Assuming there are 21 phase information points, then 10 phase differences can be obtained, including...

[0064] To better understand, let's take the three antennas in the example above (antenna A, antenna B, and antenna C, assuming antenna B is the middle antenna) as an example. This indicates the phase information of the Bluetooth signal received by antenna A for the first time. This indicates the phase information of the Bluetooth signal received by antenna B for the first time. This represents the phase information of the Bluetooth signal first received by antenna C. This indicates the phase information of the Bluetooth signal received by antenna A for the second time. This indicates the phase information of the Bluetooth signal received by antenna B for the second time. This represents the phase information of the Bluetooth signal received by antenna C for the second time. Similarly, assuming there are 20 or 21 phase information points, we can obtain 12 phase differences, including 6 phase differences between antennas A and B, and 6 phase differences between antennas B and C. The 6 phase differences between antennas A and B are as follows:

[0065]

[0066]

[0067]

[0068]

[0069]

[0070]

[0071] The six phase differences between antenna B and antenna C are as follows:

[0072]

[0073]

[0074]

[0075]

[0076]

[0077]

[0078] S3: Determine whether the amplitude of the Bluetooth signal being interfered with is within the preset amplitude range.

[0079] After obtaining multiple phase differences, it is determined whether the amplitude of signal interference on the Bluetooth signal is within a preset amplitude range. If the amplitude of signal interference on the Bluetooth signal received by the antenna is within the preset amplitude range, step S4 is executed. If the amplitude of signal interference on the Bluetooth signal received by the antenna is not within the preset amplitude range, i.e., the amplitude of signal interference on the Bluetooth signal exceeds the preset amplitude range, then the process returns to step S1, and the phase information of the Bluetooth signal received by each antenna in the Bluetooth antenna array at different times is re-acquired until the amplitude of signal interference on the Bluetooth signal is within the preset amplitude range. This step removes low-quality data, thereby improving the accuracy of the calculation results.

[0080] In one optional implementation, the process of determining whether the amplitude of signal interference to the Bluetooth signal is within a preset amplitude range may be as follows: based on multiple phase differences, determine a parameter value that characterizes the amplitude of signal interference to the Bluetooth signal, wherein the parameter value is the variance, mean, or standard deviation of the multiple phase differences; and determine whether the amplitude of signal interference to the Bluetooth signal is within the preset amplitude range by comparing the parameter value with the corresponding preset threshold.

[0081] If the parameter value is less than the preset threshold, it indicates that the amplitude of signal interference to the Bluetooth signal is within the preset range, meaning that the amplitude of signal interference to the Bluetooth signal is small and the next step of calculation can be carried out. Conversely, if the parameter value is greater, it indicates that the amplitude of signal interference to the Bluetooth signal is large and resampling is required.

[0082] Understandably, the preset threshold will vary depending on the comparison object (parameter value). If the comparison object is the variance of multiple phase differences, the preset threshold is the preset variance. If the comparison object is the mean of multiple phase differences, the preset threshold is the preset mean. If the comparison object is the standard deviation of multiple phase differences, the preset threshold is the preset standard deviation.

[0083] The preset threshold is determined in advance based on multiple first phase differences determined by the phase information of the first standard Bluetooth signal (such as a Bluetooth signal with less interference) received by each antenna at different times, and multiple second phase differences determined by the phase information of the second standard Bluetooth signal (such as a Bluetooth signal with more interference) received by each antenna at different times. If the preset threshold is a preset variance, then the preset threshold is the mean of the variances of the multiple first phase differences and the variances of the multiple second phase differences; if the preset threshold is a preset mean, then the preset threshold is the mean of the mean of the multiple first phase differences and the mean of the multiple second phase differences; if the preset threshold is a preset standard deviation, then the preset threshold is the mean of the preset standard deviations of the multiple first phase differences and the preset standard deviations of the multiple second phase differences.

[0084] For details on how to determine multiple first phase differences based on the phase information of the first standard Bluetooth signal (Bluetooth signal with less interference) received by each antenna at different times, and how to determine multiple second phase differences based on the phase information of the second standard Bluetooth signal (Bluetooth signal with more interference) received by each antenna at different times, please refer to the process described above according to step S2.

[0085] S4: Determine the angle of arrival of the Bluetooth signal based on the multiple phase differences, the wavelength of the Bluetooth signal, and the spacing between adjacent antennas.

[0086] If the amplitude of signal interference to the Bluetooth signal is within a preset range, the angle of arrival of the Bluetooth signal is determined based on multiple phase differences, the wavelength of the Bluetooth signal, and the spacing between adjacent antennas.

[0087] In one alternative implementation, the process of determining the Bluetooth signal based on multiple phase differences, the wavelength of the Bluetooth signal, and the spacing between adjacent antennas can be as follows: First, determine the product of the average of multiple phase differences and the quotient of the wavelength of the Bluetooth signal and the spacing between adjacent antennas; then, calculate the angle of arrival based on this product.

[0088] The process of determining the product of the average of multiple phase differences and the quotient of the wavelength of the Bluetooth signal and the spacing between adjacent antennas can be expressed as:

[0089] λ represents the wavelength of the Bluetooth signal, and d represents the spacing between adjacent antennas. It represents the average of multiple phase differences.

[0090] The process of calculating the angle of arrival based on this product can be achieved by using the inverse trigonometric function arccos to calculate the angle of arrival based on this product. Considering the high resource consumption of calculating the inverse trigonometric function arccos, one alternative implementation is to use a polynomial fitting algorithm, such as a 5th-order Taylor polynomial, to fit the function f(x) = arccos(x) at x = 0, and take the 5th-order expansion: in, π is 180°. Using this formula to calculate the inverse trigonometric function arccos yields results with minimal error and computational complexity. Polynomial fitting further reduces computational cost while maintaining data accuracy.

[0091] In other words, in one optional implementation, the process of determining the angle of arrival based on multiple phase differences, the wavelength of the Bluetooth signal, and the spacing between adjacent antennas is as follows: the product of the mean of multiple phase differences and the quotient of the wavelength of the Bluetooth signal and the spacing between adjacent antennas is determined, and the product is fitted using a polynomial fitting algorithm (such as a 5th-order Taylor polynomial algorithm) to determine the angle of arrival.

[0092] In one implementation, after determining the angle of arrival (Angle of Arrival) based on multiple phase differences, the wavelength of the Bluetooth signal, and the spacing between adjacent antennas, this Angle of Arrival is the final Angle of Arrival. To improve the accuracy of the calculation results, in an optional implementation, after determining the Angle of Arrival based on multiple phase differences, the wavelength of the Bluetooth signal, and the spacing between adjacent antennas, the Bluetooth direction finding method further includes: determining the final Angle of Arrival based on multiple Angles of Arrival determined over a period of time.

[0093] The process of determining the final angle of arrival based on multiple angles of arrival determined over a period of time can be as follows: take the average of the multiple angles of arrival determined over a period of time as the final angle of arrival.

[0094] In one optional implementation, the process of determining the final angle of arrival (AOA) based on multiple AOAs determined over a period of time can also involve using a median mean filtering algorithm to filter the multiple AOAs determined over a period of time to obtain the final AOA. That is, the maximum and minimum values ​​among the multiple AOAs determined over a period of time are filtered out, and then the average (mean) of the remaining AOAs is taken to obtain the final AOA. For example, if the sliding window width of the median mean filtering algorithm is 7, a sliding window with a width of 7 is used to perform median mean filtering on the results. The calculated AOA values ​​are arranged into a sequence ∠AOA(n) in chronological order. The three AOAs before time n and the three AOAs after time n are taken, plus the AOA at time n, for a total of seven values, for calculation (∠AOA). n-3 ,∠AOA n-2 ,∠AOA n-1 ,∠AOA n ,∠AOA n+1 ,∠AOAn+2 ,∠AOA n+3 At this point, n is a positive integer greater than or equal to 4; discard the maximum and minimum values, and then take the average of the remaining 5 angle values ​​as the current angle ∠AOA. n The estimated value is obtained. Finally, the stability of the angle calculation results is improved by using a sliding window filtering method.

[0095] It is understandable that the final arrival angle ∠AOA at time n is determined. n The calculation is not limited to the examples above. It could involve taking the two angles of arrival before time n and the four angles of arrival after time n, plus the angle of arrival at time n, for a total of seven values, where n is a positive integer greater than or equal to 3. Alternatively, it could involve taking the four angles of arrival before time n and the two angles of arrival after time n, plus the angle of arrival at time n, for a total of seven values, where n is a positive integer greater than or equal to 5. Therefore, the examples above should not be construed as limitations on this application.

[0096] To better understand, a schematic diagram of the Bluetooth direction finding method in one optional implementation is shown below. Figure 2 As shown. The process includes: S10: Obtaining the phase information of the Bluetooth signal received by each antenna in the Bluetooth antenna array at different times. S20: Determining multiple phase differences between adjacent antennas in the Bluetooth antenna array based on the phase information. S30: Determining whether the variance of the multiple phase differences is less than a preset threshold. If the variance of the multiple phase differences is less than the preset threshold, then execute S40; otherwise, return to S10 and re-obtain the phase information of the Bluetooth signal received by each antenna in the Bluetooth antenna array at different times. S40: Determining the angle of arrival (Angle of Arrival) of the Bluetooth signal based on the multiple phase differences, the wavelength of the Bluetooth signal, and the spacing between adjacent antennas. S50: Determining the final Angle of Arrival (Angle of Arrival) based on the multiple Angles of Arrival determined over a period of time.

[0097] Understandable Figure 2 The schematic diagram shown is only one of many embodiments and should not be construed as a limitation of this application.

[0098] Based on the same inventive concept, this application also provides a terminal device 100, as shown in FIG3. The terminal device includes a Bluetooth module 110 and a processor 120. The terminal device 100 includes, but is not limited to, mobile phones, tablets, computers, and in-vehicle devices.

[0099] Bluetooth module 110 includes a Bluetooth antenna array and a Bluetooth chip. The Bluetooth antenna array and the Bluetooth chip are connected. The Bluetooth chip is used to control the Bluetooth antenna array to transmit and receive signals. The Bluetooth chip is used to perform IQ sampling on the Bluetooth signals received by each antenna in the Bluetooth antenna array at different times, determine the corresponding phase information based on the IQ sampling values, and send the obtained phase information of the Bluetooth signals received by each antenna at different times to processor 120.

[0100] The processor 120 is configured to obtain phase information of Bluetooth signals received by each antenna in the Bluetooth antenna array at different times from the Bluetooth module 110, determine multiple phase differences between adjacent antennas in the Bluetooth antenna array based on the phase information, and determine whether the amplitude of signal interference to the Bluetooth signal is within a preset amplitude range; if the amplitude of signal interference to the Bluetooth signal is within the preset amplitude range, determine the angle of arrival of the Bluetooth signal based on the multiple phase differences, the wavelength of the Bluetooth signal, and the spacing between adjacent antennas.

[0101] Optionally, the processor 120 is configured to determine the phase difference between adjacent antennas based on the phase information of Bluetooth signals received by one of the adjacent antennas in two consecutive receptions and the phase information of Bluetooth signals received by the other of the adjacent antennas in a previous reception.

[0102] The processor 120 is configured to determine, based on the plurality of phase differences, a parameter value representing the magnitude of signal interference to the Bluetooth signal, wherein the parameter value is the variance, mean, or standard deviation of the plurality of phase differences; and to determine whether the magnitude of signal interference to the Bluetooth signal is within a preset range by comparing the parameter value with a corresponding preset threshold; wherein, if the parameter value is less than the preset threshold, it indicates that the magnitude of signal interference to the Bluetooth signal is within the preset range.

[0103] Processor 120 is configured to determine the product of the mean of the plurality of phase differences and the quotient of the wavelength of the Bluetooth signal and the distance between adjacent antennas; and to fit the product using a polynomial fitting algorithm to determine the angle of arrival.

[0104] After determining the angle of arrival of the Bluetooth signal based on the plurality of phase differences, the wavelength of the Bluetooth signal, and the spacing between adjacent antennas, the processor 120 is further configured to determine the final angle of arrival based on the plurality of angles of arrival determined over a period of time.

[0105] Processor 120 is used to filter multiple angles of arrival determined over a period of time using a median mean filtering algorithm to obtain the final angle of arrival.

[0106] The terminal device 100 provided in this application embodiment has the same implementation principle and technical effect as the aforementioned method embodiment. For the sake of brevity, any parts not mentioned in the terminal device 100 embodiment can be referred to the corresponding content in the aforementioned method embodiment.

[0107] like Figure 4 As shown, Figure 4 This diagram illustrates a structural block diagram of an electronic device 200 according to an embodiment of this application. The electronic device 200 includes a transceiver 210, a memory 220, a communication bus 230, and a processor 240. Optionally, the electronic device 200 further includes a Bluetooth module, wherein the Bluetooth module includes a Bluetooth antenna array and a Bluetooth chip. The Bluetooth module and the processor 240 are connected. The Bluetooth chip is used to perform IQ sampling on the Bluetooth signals received by each antenna in the Bluetooth antenna array at different times to obtain corresponding phase information, and then transmit this information to the processor 240.

[0108] The transceiver 210, memory 220, and processor 240 are electrically connected directly or indirectly to achieve data transmission or interaction. For example, these components can be electrically connected to each other through one or more communication buses 230 or signal lines. The transceiver 210 is used to send and receive data. The memory 220 is used to store computer programs or software functional modules, including at least one software functional module that can be stored in the memory 220 in the form of software or firmware or embedded in the operating system (OS) of the electronic device 200. The processor 240 is used to execute the software functional modules or computer programs stored in the memory 220. For example, processor 240 is used to acquire phase information of Bluetooth signals received by each antenna in the Bluetooth antenna array at different times; determine multiple phase differences between adjacent antennas in the Bluetooth antenna array based on the phase information; determine whether the amplitude of signal interference to the Bluetooth signal is within a preset amplitude range; if the amplitude of signal interference to the Bluetooth signal is within the preset amplitude range, determine the angle of arrival of the Bluetooth signal based on the multiple phase differences, the wavelength of the Bluetooth signal and the spacing between adjacent antennas.

[0109] The memory 220 may be, but is not limited to, random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), etc.

[0110] Processor 240 may be an integrated circuit chip with signal processing capabilities. The aforementioned processor can be a general-purpose processor, including a Central Processing Unit (CPU), a Network Processor (NP), etc.; it can also be a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this application. The general-purpose processor can be a microprocessor, or processor 240 can be any conventional processor.

[0111] Among them, the aforementioned electronic devices 200 include, but are not limited to, mobile phones, tablets, computers, in-vehicle devices, servers, etc.

[0112] This application embodiment also provides a non-volatile computer-readable storage medium (hereinafter referred to as the storage medium) storing a computer program, which is executed by a computer such as the electronic device 200 described above to perform the Bluetooth direction finding method described above.

[0113] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the various embodiments can be referenced to each other.

[0114] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can also be implemented in other ways. The device embodiments described above are merely illustrative. For example, the flowcharts and block diagrams in the accompanying drawings show the possible architectures, functions and operations of the devices, methods and computer program products according to the multiple embodiments of the present application. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of the code, and the module, program segment or a part of the code contains one or more executable instructions for implementing the specified logical functions. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in an order different from that marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart, and the combination of boxes in the block diagram and / or flowchart, can be implemented using a dedicated hardware-based system that performs the specified function or action, or can be implemented using a combination of dedicated hardware and computer instructions.

[0115] In addition, the functional modules in the various embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0116] If the aforementioned functions are implemented as software functional modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a computer-readable storage medium and includes several instructions to cause a computer device (which may be a personal computer, laptop, server, or electronic device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned computer-readable 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.

[0117] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A Bluetooth direction finding method, characterized in that, include: Obtain the phase information of the Bluetooth signals received by each antenna in the Bluetooth antenna array at different times; Based on the phase information, multiple phase differences between each adjacent antenna in the Bluetooth antenna array are determined; Determine whether the magnitude of signal interference affecting the Bluetooth signal is within a preset range; If the amplitude of the signal interference to the Bluetooth signal is within a preset amplitude range, the angle of arrival of the Bluetooth signal is determined based on the multiple phase differences, the wavelength of the Bluetooth signal, and the spacing between adjacent antennas. The determination of the phase difference between adjacent antennas in the Bluetooth antenna array based on the phase information includes: For any adjacent antenna in the Bluetooth antenna array, obtain the phase information of the Bluetooth signal received by one of the adjacent antennas in two consecutive times, and the phase information of the Bluetooth signal received by the other antenna in the previous time. Obtain the first difference in phase information of the Bluetooth signals received by one of the antennas in two separate instances; Obtain a second difference between the phase information of the Bluetooth signal previously received by the other antenna and the phase information of the Bluetooth signal previously received by one of the antennas; The phase difference between the adjacent antennas is determined based on the first difference and the second difference.

2. The method according to claim 1, characterized in that... Determining whether the magnitude of signal interference affecting the Bluetooth signal is within a preset range includes: Based on the multiple phase differences, a parameter value characterizing the magnitude of signal interference to the Bluetooth signal is determined, wherein the parameter value is the variance, mean, or standard deviation of the multiple phase differences; By comparing the parameter value with the corresponding preset threshold, it is determined whether the amplitude of signal interference to the Bluetooth signal is within the preset amplitude range. If the parameter value is less than the preset threshold, it indicates that the amplitude of signal interference to the Bluetooth signal is within the preset amplitude range.

3. The method according to claim 2, characterized in that, The preset threshold is determined in advance based on multiple first phase differences determined according to the phase information of the first standard Bluetooth signal received by each antenna at different times and multiple second phase differences determined according to the phase information of the second standard Bluetooth signal received by each antenna at different times.

4. The method according to claim 1, characterized in that, The angle of arrival of the Bluetooth signal is determined based on the multiple phase differences, the wavelength of the Bluetooth signal, and the spacing between adjacent antennas, including: Determine the product of the average of the multiple phase differences and the quotient of the wavelength of the Bluetooth signal and the spacing between adjacent antennas; The product is fitted using a polynomial fitting algorithm to determine the angle of arrival.

5. The method according to claim 1, characterized in that, After determining the angle of arrival of the Bluetooth signal based on the multiple phase differences, the wavelength of the Bluetooth signal, and the spacing between adjacent antennas, the method further includes: The final angle of arrival is determined based on multiple angles of arrival determined over a period of time.

6. The method according to claim 5, characterized in that, The final angle of arrival is determined based on multiple angles of arrival determined over a period of time, including: The median mean filtering algorithm is used to filter multiple angles of arrival determined over a period of time to obtain the final angle of arrival.

7. The method according to any one of claims 1-6, characterized in that, Obtain the phase information of the Bluetooth signals received by each antenna in the Bluetooth antenna array at different times, including: The IQ sampling is performed on the Bluetooth signals received by each antenna in the Bluetooth antenna array at different times, and the corresponding phase information is determined based on the IQ sampling values.

8. The method according to any one of claims 1-6, characterized in that, After determining whether the amplitude of signal interference to the Bluetooth signal is within a preset amplitude range, the method further includes: If the amplitude of the Bluetooth signal interference is not within the preset amplitude range, the phase information of the Bluetooth signal received by each antenna in the Bluetooth antenna array at different times is reacquired.

9. A terminal device, characterized in that, include: The Bluetooth module includes a Bluetooth antenna array and a Bluetooth chip; the Bluetooth chip is used to perform IQ sampling on the Bluetooth signals received by each antenna in the Bluetooth antenna array at different times, and determine the corresponding phase information based on the IQ sampling values. The processor is configured to obtain phase information of Bluetooth signals received by each antenna in the Bluetooth antenna array at different times from the Bluetooth module, determine multiple phase differences between adjacent antennas in the Bluetooth antenna array based on the phase information, and determine whether the amplitude of the Bluetooth signal being interfered with is within a preset amplitude range. If the amplitude of the signal interference to the Bluetooth signal is within a preset amplitude range, the angle of arrival of the Bluetooth signal is determined based on the multiple phase differences, the wavelength of the Bluetooth signal, and the spacing between adjacent antennas. The processor is specifically configured to, for any adjacent antenna in the Bluetooth antenna array, acquire phase information of Bluetooth signals received by one of the adjacent antennas in two consecutive receptions, and phase information of Bluetooth signals received by the other adjacent antenna in a previous reception; acquire a first difference between the phase information of the Bluetooth signals received by the one of the adjacent antennas in two consecutive receptions; acquire a second difference between the phase information of the Bluetooth signals received by the other antenna in a previous reception and the phase information of the Bluetooth signals received by the one of the adjacent antennas in a previous reception; and determine the phase difference between the adjacent antennas based on the first difference and the second difference.

10. An electronic device, characterized in that, include: A memory and a processor, wherein the processor is connected to the memory; The memory is used to store programs; The processor is configured to invoke a program stored in the memory to execute the method as described in any one of claims 1-8.

11. A computer-readable storage medium, characterized in that, It stores a computer program, which, when executed by a processor, performs the method as described in any one of claims 1-8.

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