Multi-device angular positioning and user identification method

Abstract

The present invention discloses a multi-device angle positioning and user identification method, the method comprising: the user sends a positioning signal, the first receiving module receives the signals M1, M2, M3..., and solves to obtain [T, F d ] p The signals received by the second receiving module are m1, m2, m3, etc., and the solution is [τ, f d ] r Group, comparison [T, F d ] p and [τ, f d ] r , find the corresponding [T, F d :τ,f d ] g The present invention uses the constraints of the mobile device being much smaller than the positioning size and much slower than the application scenario to compare the time delay and Doppler frequency deviation of the positioning signals received by different receiving modules. It then finds two sets of time delay and Doppler frequency deviation data corresponding to the same positioning signal, thereby accurately determining the user's position relative to the mobile device.

Description

Technical Field

[0001] The invention relates to a method for angle positioning and user identification of multiple devices, belonging to the technical field of positioning. Background Art

[0002] The Internet of Things (IoT) refers to the real-time collection of acoustic, optical, thermal, electrical, mechanical, chemical, biological, and location-based information from any object or process requiring monitoring, connection, and interaction, using various devices and technologies, including information sensors, radio frequency identification (RFID), global positioning systems (GPS), infrared sensors, and laser scanners. This information is then collected through various network connections, enabling ubiquitous connectivity between objects and between objects and people, and enabling intelligent perception, identification, and management of objects and processes. The IoT is an information carrier based on the internet and traditional telecommunications networks, enabling all independently addressable, common physical objects to form an interconnected network.

[0003] In physical network scenarios, intelligent interactions between devices, and between control devices and scene devices, are achieved through wireless communication connections. However, wireless communication can only achieve basic connection control and cannot complete many personalized and intelligent operations. These operations are all based on location perception between devices and are implemented in conjunction with wireless communication. Currently, since it is difficult to receive satellite positioning signals in indoor scenarios, other positioning methods need to be adopted indoors. Given the low cost and high precision of ultrasound, acoustic positioning is used to achieve location perception between indoor devices. However, when a handheld / worn mobile device interacts with a large number of devices in the environment, it receives a large number of positioning signals at the same time, making it difficult for the mobile device to identify the owner of the positioning signal and to aggregate data corresponding to different receiving ends for the same signal, making it difficult to calculate relative position. Summary of the Invention

[0004] The purpose of the present invention is to provide a multi-device angle positioning and user identification method, which solves the problem in the prior art that when multiple devices are positioned simultaneously, user identification is difficult, data from different receiving ends is difficult to match, and the positioning function cannot be realized.

[0005] To achieve the above-mentioned object, the present invention adopts a technical solution: a method for angular positioning and user identification of multiple devices, the method comprising:

[0006] Signal design: Using OFDM structure signals, several users are placed on agreed subcarriers to form different positioning signals;

[0007] Positioning perception: The user sends a positioning signal, and several positioning signals are received by the first receiving module and the second receiving module installed on the mobile device respectively. The signals received by the first receiving module are M1, M2, M3, etc., and the solution is [T, F d ] p group, where T is the positioning signal delay, F d To locate the signal Doppler shift, the second receiving module receives the signal m1, m2, m3, etc., and the solution is [τ, f d ] r group, where τ is the positioning signal delay, f d To locate the signal Doppler frequency shift, compare [T, F d ] p and [τ, f d ] r , find the corresponding [T, F d :τ,f d ] g group, identify users and calculate the positions of several users relative to the mobile device.

[0008] The further improved scheme in the above technical scheme is as follows:

[0009] 1. In the above solution, the positioning signal is an ultrasonic positioning signal.

[0010] 2. In the above solution, there are multiple users and one mobile device.

[0011] 3. In the above solution, there is a protection bandwidth between the subcarriers of different users.

[0012] 4. In the above scheme, judge [T, F d ] p and [τ, f d ] r The methods belonging to the same positioning signal are:

[0013] Step 1: Find the d1 The closest f dh , h is a value between 1 and r;

[0014] Step 2: If |T1-τ h |·c≤D, that is, to judge [T, F d ]1 and [τ, f d ] h Belong to the same positioning signal and record and collect;

[0015] If |T1-τ h |·c>D, then exclude f dh , find the remaining data closest to F d1 fdo , o is a value between 1 and r;

[0016] If |T1-τ o |·c≤D, that is, to judge [T, F d ]1 and [τ, f d ] o Belong to the same positioning signal and record and collect;

[0017] Otherwise, the above steps are repeated until a corresponding group that meets the conditions is obtained;

[0018] Set all [T, F d ]Substitute the above steps until all [T, F d ] p and [τ, f d ] r The corresponding relationship is recorded and stored;

[0019] Wherein, c is the propagation speed of the positioning signal, and D is the shortest distance between the first receiving module and the second receiving module on the mobile device.

[0020] 5. In the above scheme, if there are two [τ, f d ] satisfies any [T, F d ] in the same group of judgment conditions, select the one with larger correlation peak energy [τ, f d ].

[0021] 6. In the above solution, the position of the user relative to the mobile device includes a relative angle θ,

[0022] 7. In the above solution, the position of the user relative to the mobile device includes a distance, the distance between the first receiving module and the user is L1 = T·c, and the distance between the second receiving module and the user is L2 = τ·c.

[0023] 8. In the above solution, the method for estimating the Doppler shift of the positioning signal is:

[0024] After the user sends a real-valued signal x(λ) at the first moment;

[0025] The second receiving module collects a received signal at the second moment, which is recorded as y(λ), where x(λ) and y(λ) are both baseband time domain signals;

[0026] The configured processor gets: Where, τ′ = second moment - first moment;

[0027] The processor performs fast Fourier transform on the received signal to obtain: Y(n)=X(nf d )e j2πτn, n=1,2……N;

[0028] Create a new function: Y(1:N-1)·conj(Y(2:N))=X((1:N-1)-f d )·X * ((2:N)-f d )·e j2πV ; Screening constant e j2πτ , output X((1:N-1)-f d )·X * ((2:N)-f d );

[0029] Use real-valued signals to create a new function without frequency deviation: X(1:N-1)·X * (2:N);

[0030] Through the processor X(kf d )·X * ((k+1)-f d ) and X(k)·X * Substitute (k+1) into the cross-correlation function to obtain the frequency deviation f d =BA, where the original peak point is at A and the shifted peak point is at B, output frequency deviation;

[0031] Among them, k=1:N-1.

[0032] 9. In the above solution, the method for correcting the positioning signal delay is:

[0033] Correct y(λ) using the frequency offset to obtain y(λ) new , y(λ) new Substitute x(λ) and x(λ) into the cross-correlation function and modify τ' to obtain τ.

[0034] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0035] 1. The multi-device angular positioning and user identification method of the present invention places different users at different positions in the same signal structure by agreeing on subcarrier signals, making it easier for mobile devices to identify users through agreed protocols. At the same time, by utilizing the constraints that the size of the mobile device is much smaller than the positioning size and the movement speed is much smaller than the application scenario, the time delay and Doppler frequency deviation of the positioning signals received by different receiving modules are compared, and two sets of time delay and Doppler frequency deviation data corresponding to the same positioning signal can be found, thereby obtaining the precise position of the user relative to the mobile device. Ultrasonic directionality has stronger anti-interference ability and expands the number of users that can be accommodated by ultrasonic positioning.

[0036] 2. The multi-device angular positioning and user identification method of the present invention adds a protection bandwidth between the subcarriers of different users, so that the subcarriers of different users will not interfere with each other, and the subcarriers of different users can be easily separated at the receiving module.

[0037] 3. The angle positioning and user identification method of multiple devices of the present invention obtains Doppler frequency shift by constructing a function that satisfies the cross-correlation function, which is used to correct the received signal. The corrected received signal is then used to construct a function that satisfies the cross-correlation function, reversely correct the delay, eliminate errors, obtain a more accurate delay value, and improve positioning accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Attachment Figure 1 This is a modular schematic diagram of the multi-device angle positioning and user identification method of the present invention. DETAILED DESCRIPTION

[0039] Example 1: A method for multi-device angle positioning and user identification, see the attached Figure 1 , the method comprising:

[0040] S1: Signal design uses OFDM structure signals, or OFDM-like uplink and downlink structure signals, as agreed signals. Different users are placed on agreed subcarriers to form corresponding positioning signals.

[0041] Here, the positioning signal is an ultrasonic positioning signal, and before positioning perception, the user and the mobile device complete the signal carrying protocol through wireless communication;

[0042] Here, a guard band is designed between the subcarriers of different users to prevent them from interfering with each other, and the subcarriers of different users can be easily separated at the receiving module;

[0043] Here, if the total number of subcarriers in the OFDM structure signal is greater than the number of subcarriers used by the user, the value at the position of the vacant subcarrier is 0.

[0044] S2: Positioning interaction: Different users send their own positioning signals. Multiple direct positioning signals are received by a first receiving module and a second receiving module installed on the mobile device. The signals received by the first receiving module are labeled M1, M2, M3, etc., and the signals received by the second receiving module are labeled m1, m2, m3, etc.;

[0045] Here, the user sends a positioning signal through the speaker unit, and the positioning signal also carries the sending time. When the receiving module receives the positioning signal mark through the microphone unit, it records the receiving time.

[0046] S3: Signal aggregation, through the pre-written solution instructions in the processor configured in the mobile device, derive the [T, F] corresponding to M1, M2, M3, ... d ] p group, where p = 1, 2, 3, ..., T is the positioning signal delay, F d To locate the signal Doppler shift, derive [τ, f d ] r group, where r = 1, 2, 3, ..., τ is the positioning signal delay, f d is the Doppler shift of the positioning signal.

[0047] Multi-path analysis module determines [T, F d ] p and [τ, f d ] r The methods belonging to the same positioning signal are:

[0048] Step 1: Find the d1 The closest f dh , h is a value between 1 and r;

[0049] Step 2: If |T1-τ h |·c≤D, that is, to judge [T, F d ]1 and [τ, f d ] h Belong to the same positioning signal and record and collect;

[0050] If |T1-τ h |·c>D, then exclude f dh , find the remaining data closest to F d1 f do , o is a value between 1 and r;

[0051] If |T1-τ o |·c≤D, that is, to judge [T, F d ]1 and [τ, f d ] o Belong to the same positioning signal and record and collect;

[0052] Otherwise, the above steps are repeated until a corresponding group that meets the conditions is obtained;

[0053] Set all [T, F d ]Substitute the above steps until all [T, F d ] p and [τ, f d ] r The corresponding relationship is recorded and stored as [T, F d :T,f d ]g Group;

[0054] Where c is the propagation speed of the positioning signal (the speed of ultrasonic waves propagating in the air), and D is the shortest distance between the first receiving module and the second receiving module on the mobile device;

[0055] Here, the mobile device is a mobile phone, and the first receiving module and the second receiving module are installed at both ends of the mobile phone respectively. For the positioning environment, the size and movement speed of the mobile phone are very small. At this time, the Doppler frequency shifts of different receiving modules are almost the same.

[0056] In addition, the estimation method of the positioning signal Doppler shift is:

[0057] After the user sends a real-valued signal x(λ) at the first moment;

[0058] The second receiving module collects and obtains a received signal at the second moment, and obtains y(λ) through the analog-to-digital conversion module and the baseband conversion module. x(λ) and y(λ) are all baseband time domain signals;

[0059] The configured processor gets: Where, τ = second moment - first moment;

[0060] The FFT module of the processor performs a fast Fourier transform on the received signal to obtain: Y(n)=x(nf d )e j2 πτn , n=1,2……N;

[0061] Create a new function: Y(1:N-1)·conj(Y(2:N))=X((1:N-1)-f d )·X * ((2:N)-f d )·e j2πτ ; Screening constant e j2πτ , output X((1:N-1)-f d )·X * ((2:N)-f d );

[0062] Use real-valued signals to create a new function without frequency deviation: X(1:N-1)·X * (2:N);

[0063] Through the processor X(kf d )·X * ((k+1)-f d ) and X(k)·X * Substitute (k+1) into the cross-correlation function to obtain the frequency deviation f d=BA, where the original peak point is at A and the shifted peak point is at B. The delay and frequency offset estimation module outputs the delay and frequency offset, and the user identification module outputs the user being identified based on the subcarrier information.

[0064] Among them, k=1:N-1.

[0065] S4: Positioning perception: According to [T, F d : τ, f d ] g The relative position calculation module outputs the position of the user relative to the mobile device. The relative position here includes distance and relative angle. The angle of the user relative to the mobile device is θ. The distance between the first receiving module and the user is L1 = T·c, and the distance between the second receiving module and the user is L2 = τ·c.

[0066] Example 2: A method for multi-device angle positioning and user identification, see the attached Figure 1 , the method comprising:

[0067] S1: Signal design uses OFDM structure signals, or OFDM-like uplink and downlink structure signals, as agreed signals. Different users are placed on agreed subcarriers to form corresponding positioning signals.

[0068] Here, the positioning signal is an ultrasonic positioning signal, and before positioning perception, the user and the mobile device complete the signal carrying protocol through wireless communication;

[0069] Here, a guard band is designed between the subcarriers of different users to prevent them from interfering with each other, and the subcarriers of different users can be easily separated at the receiving module;

[0070] Here, if the total number of subcarriers in the OFDM structure signal is greater than the number of subcarriers used by the user, the value at the position of the vacant subcarrier is 0.

[0071] S2: Positioning interaction: Different users send their own positioning signals. Multiple direct positioning signals are received by a first receiving module and a second receiving module installed on the mobile device. The signals received by the first receiving module are labeled M1, M2, M3, etc., and the signals received by the second receiving module are labeled m1, m2, m3, etc.;

[0072] Here, the user sends a positioning signal through the speaker unit. The positioning signal also carries the sending time, and when the receiving module receives the positioning signal mark through the microphone unit, it records the receiving time; and the mobile device can be set to multiple to perform positioning interaction separately.

[0073] S3: Signal aggregation, through the pre-written solution instructions in the processor configured in the mobile device, derive the [T, F] corresponding to M1, M2, M3, ... d ] p group, where p = 1, 2, 3, ..., T is the positioning signal delay, F d To locate the signal Doppler shift, derive [τ, f d ] r group, where r = 1, 2, 3, ..., τ is the positioning signal delay, f d is the Doppler shift of the positioning signal.

[0074] Judge [T, F d ] p and [τ, f d ] r The methods belonging to the same positioning signal are:

[0075] Step 1: Find the d1 The closest f dh , h is a value between 1 and r;

[0076] Step 2: If |T1-τ h |·c≤D, that is, to judge [T, F d ]1 and [τ, f d ] h Belong to the same positioning signal and record and collect;

[0077] If |T1-τ h |·c>D, then exclude f dh , find the remaining data closest to F d1 f do , o is a value between 1 and r;

[0078] If |T1-τ o |·c≤D, that is, to judge [T, F d ]1 and [τ, f d ] o Belong to the same positioning signal and record and collect;

[0079] Otherwise, the above steps are repeated until a corresponding group that meets the conditions is obtained;

[0080] Among them, if there are two [τ, f d ] satisfies any [T, F d ], select the one with larger correlation peak energy [τ, f d ];

[0081] Set all [T, F d ]Substitute the above steps until all [T, Fd ] p and [τ, f d ] r The corresponding relationship is recorded and stored as [T, F d :τ,f d ] g Group;

[0082] Where c is the propagation speed of the positioning signal (the speed of ultrasonic waves propagating in the air), and D is the shortest distance between the first receiving module and the second receiving module on the mobile device;

[0083] Here, the mobile device is a mobile phone, and the first receiving module and the second receiving module are installed at both ends of the mobile phone respectively. For the positioning environment, the size and movement speed of the mobile phone are very small. At this time, the Doppler frequency shifts of different receiving modules are almost the same.

[0084] In addition, the estimation method of the positioning signal Doppler shift is:

[0085] After the user sends a real-valued signal x(λ) at the first moment;

[0086] The second receiving module collects a received signal at the second moment, which is recorded as y(λ), where x(λ) and y(λ) are both baseband time domain signals;

[0087] The configured processor gets: Where, τ′ = second moment - first moment;

[0088] The processor performs fast Fourier transform on the received signal to obtain: Y(n)=X(nf d )e j2πτn , n=1,2……N;

[0089] Create a new function: Y(1:N-1)·conj(Y(2:N))=X((1:N-1)-f d )·X * ((2:N)-f d )·e j2πτ ; Screening constant e j2πτ , output x((1:N-1)-f d )·X * ((2:N)-f d );

[0090] Use real-valued signals to create a new function without frequency deviation: X(1:N-1)·X * (2:N);

[0091] Through the processor X(kf d )·X * ((k+1)-fd ) and X(k)·X * Substitute (k+1) into the cross-correlation function to obtain the frequency deviation f d =BA, where the original peak point is at A and the shifted peak point is at B, output frequency deviation;

[0092] Among them, k=1:N-1.

[0093] In order to further improve positioning accuracy and eliminate delay errors, the positioning signal delay correction method is as follows:

[0094] Correct y(λ) using the frequency offset to obtain y(λ) new =y(λ)*exp(-1j2πf d λ), y(λ) new Substitute x(λ) and x(λ) into the cross-correlation function and modify τ' to obtain τ.

[0095] S4: Positioning perception: According to [T, F d :τ,f d ] g group, identifies the user and outputs the position of the user relative to the mobile device, where the relative position includes distance and relative angle, and the angle of the user relative to the mobile device is θ, The distance between the first receiving module and the user is L1 = T·c, and the distance between the second receiving module and the user is L2 = τ·c.

[0096] By adopting the above scheme, different users are placed at different positions in the same signal structure through the agreed subcarrier signal, which makes it easier for mobile devices to identify users through the agreed protocol. At the same time, by taking advantage of the constraints that the size of the mobile device is much smaller than the positioning size and the movement speed is much smaller than the application scenario, the time delay and Doppler frequency deviation of the positioning signal received by different receiving modules are compared. The two sets of time delay and Doppler frequency deviation data corresponding to the same positioning signal can be found, thereby obtaining the precise position of the user relative to the mobile device. The ultrasonic directionality has stronger anti-interference ability and expands the number of users that can be accommodated by ultrasonic positioning.

[0097] In addition, by adding a guard bandwidth between the subcarriers of different users, the subcarriers of different users will not interfere with each other, and the subcarriers of different users can be easily separated at the receiving module.

[0098] In addition, by constructing a cross-correlation function, the Doppler frequency shift is obtained to correct the received signal, and then the corrected received signal is used to construct a cross-correlation function to reversely correct the delay, eliminate the error, obtain a more accurate delay value, and improve the positioning accuracy.

[0099] The above embodiments are intended only to illustrate the technical concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made in accordance with the spirit of the present invention are intended to be covered by the scope of protection of the present invention.

Claims

1. A method for angle positioning and user identification of multiple devices, characterized in that: The method comprises: Signal design: Using OFDM structure signals, several users are placed on agreed subcarriers to form different positioning signals; Positioning perception: The user sends a positioning signal, and several positioning signals are received by the first receiving module and the second receiving module installed on the mobile device respectively. The signals received by the first receiving module are M1, M2, M3, etc., and the solution is [T, F d ] p group, where T is the positioning signal delay, F d To locate the signal Doppler shift, the second receiving module receives the signal m1, m2, m3, etc., and the solution is [τ, f d ] r group, where τ is the positioning signal delay, f d To locate the signal Doppler frequency shift, compare [T, F d ] p and [τ, f d ] r , find the corresponding [T, F d :τ,f d ] g group, identify users and calculate the positions of several users relative to the mobile device.

2. The multi-device angle positioning and user identification method according to claim 1, characterized in that: The positioning signal is an ultrasonic positioning signal.

3. The multi-device angle positioning and user identification method according to claim 1, characterized in that: There are multiple users and one mobile device.

4. The multi-device angle positioning and user identification method according to claim 1, characterized in that: There is a guard bandwidth between the subcarriers of different users.

5. The multi-device angle positioning and user identification method according to claim 1, characterized in that: Judge [T, F d ] p and [τ, f d ] r The methods belonging to the same positioning signal are: Step 1: Find the d1 The closest f dh , h is a value between 1 and r; Step 2: If |T1-τ h |·c≤D, that is, to judge [T, F d ]1 and [τ, f d ] h Belong to the same positioning signal and record and collect; If |T1-τ h |·c>D, then exclude f dh , find the remaining data closest to F d1 f do , o is a value between 1 and r; If |T1-τ o |·c≤D, that is, to judge [T, F d ]1 and [τ, f d ] o Belong to the same positioning signal and record and collect; Otherwise, the above steps are repeated until a corresponding group that meets the conditions is obtained; Set all [T, F d ]Substitute the above steps until all [T, F d ] p and [τ, f d ] r The corresponding relationship is recorded and stored; Wherein, c is the propagation speed of the positioning signal, and D is the shortest distance between the first receiving module and the second receiving module on the mobile device.

6. The multi-device angle positioning and user identification method according to claim 5, characterized in that: If there are two [τ, f d ] satisfies any [T, F d ] in the same group of judgment conditions, select the one with larger correlation peak energy [T, f d ].

7. The multi-device angle positioning and user identification method according to claim 5, characterized in that: The position of the user relative to the mobile device includes a relative angle θ, 8. The multi-device angle positioning and user identification method according to claim 5, characterized in that: The position of the user relative to the mobile device includes a distance. The distance between the first receiving module and the user is L1 = T·c, and the distance between the second receiving module and the user is L2 = τ·c.

9. The multi-device angle positioning and user identification method according to claim 1, characterized in that: The estimation method of the positioning signal Doppler shift is: After the user sends a real-valued signal x(λ) at the first moment; The second receiving module collects a received signal at the second moment, which is recorded as y(λ), where x(λ) and y(λ) are both baseband time domain signals; The configured processor gets: Where, τ′ = second moment - first moment; The processor performs fast Fourier transform on the received signal to obtain: Y(n)=X(nf d )e j2πτ′n , n=1,2……N; Create a new function: Y(1:N-1)·conj(Y(2:N))=X((1:N-1)-f d )·X * ((2:N)-f d )·e j2πτ′ ; Screening constant e j2πτ′ , output X((1:N-1)-f d )·X * ((2:N)-f d ); Use real-valued signals to create a new function without frequency deviation: X(1:N-1)·X * (2:N); Through the processor X(kf d )·X * ((k+1)-f d ) and X(k)·X * Substitute (k+1) into the cross-correlation function to obtain the frequency deviation f d =BA, where the original peak point is at A and the shifted peak point is at B, output frequency deviation; Among them, k=1:N-1.

10. The multi-device angle positioning and user identification method according to claim 9, characterized in that: The correction method of the positioning signal delay is: Correct y(λ) using the frequency offset to obtain y(λ) new , y(λ) new Substitute x(λ) and x(λ) into the cross-correlation function and modify τ′ to obtain τ.

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