Portable positioning system based on Bluetooth AOA positioning and method thereof

Abstract

The invention discloses a portable positioning system based on Bluetooth AOA positioning. The portable positioning system comprises a Bluetooth terminal device, a portable Bluetooth positioning base station and a mobile terminal. After the mobile terminal sends the information of the Bluetooth terminal device needing to be positioned to the portable Bluetooth positioning base station, the portable Bluetooth positioning base station carries out positioning scanning, and after a Bluetooth AoA positioning signal sent by the target Bluetooth terminal device is scanned, the Bluetooth AoA positioning signal is sent to the mobile terminal. And resolving the phase data through a Bluetooth AoA positioning algorithm of the MCU to obtain azimuth angle and distance information of the target Bluetooth terminal equipment, receiving data of the portable Bluetooth positioning base station by the mobile terminal, and displaying position information of the Bluetooth terminal equipment relative to the mobile terminal on an interface. By adopting the portable Bluetooth positioning base station and the mobile terminal capable of communicating with the portable Bluetooth positioning base station, the Bluetooth positioning terminal equipment can be positioned in an outdoor scene without a fixed positioning base station.

Description

Technical Field

[0001] The present invention relates to the field of Bluetooth positioning, and in particular to a portable positioning system and method based on Bluetooth AOA positioning. Background Art

[0002] Among Bluetooth positioning methods, Bluetooth AOA (Angle of Arrive) positioning is widely used.

[0003] During the Bluetooth AOA positioning process, the device to be located transmits a special modulated signal. The positioning base station receives the modulated signal through a specially arranged antenna array, and then identifies the angle of the device to be located relative to the positioning base station, thereby further determining the position of the device to be located relative to the positioning base station.

[0004] The device to be located needs to have the function of supporting the transmission of the specific modulated signal in the Bluetooth baseband, and the positioning base station needs to have the switching and scanning functions of the antenna array according to the received Bluetooth data.

[0005] For example, the patent document with application number 202022664034.4 discloses an indoor positioning device based on Bluetooth AOA positioning technology, including: an array antenna module and a processor module, wherein the array antenna module is used to receive multi-channel fixed-frequency signals transmitted by the same terminal from the antenna end, and output the corresponding I / Q value of the signal; the processor module is used to control the array antenna module to select the corresponding antenna to receive the terminal signal, and based on the Bluetooth AOA positioning technology, calculate the angle between the terminal and the positioning device according to the I / Q value output by the array antenna module, and convert the distance between the two.

[0006] The above technical solution can achieve accurate indoor positioning only through the array antenna module and the processor module, and has high positioning accuracy based on the Bluetooth AOA positioning technology.

[0007] However, since some located objects (such as movable assets, pets, etc.) may accidentally leave the signal coverage of the indoor positioning base station, when the positioning device does not support outdoor positioning functions such as GPS, manual retrieval is difficult.

[0008] Therefore, it is necessary for us to improve the above-mentioned prior art to overcome the above-mentioned defects. Summary of the invention

[0009] The purpose of the present invention is to provide a portable positioning system and method based on Bluetooth AOA positioning to solve the problems existing in the prior art.

[0010] The above technical objectives of the present invention are achieved through the following technical solutions:

[0011] A portable positioning system based on Bluetooth AOA positioning, comprising:

[0012] A Bluetooth terminal device, which is used to periodically send Bluetooth AoA positioning signals;

[0013] A portable Bluetooth positioning base station, which is used to receive Bluetooth AoA positioning signals and calculate the azimuth and distance of the received Bluetooth AoA positioning signals through an embedded Bluetooth AoA positioning algorithm;

[0014] The mobile terminal is used to communicate with the portable Bluetooth positioning base station, send the information of the Bluetooth terminal device to be located to the portable Bluetooth positioning base station, and receive and display the angle and distance information of the Bluetooth terminal device fed back by the portable Bluetooth positioning base station.

[0015] Furthermore, the portable Bluetooth positioning base station includes a power module, an MCU, a Bluetooth chip, a posture sensor and a combined antenna;

[0016] The power module includes a rechargeable battery pack and a DC adapter, which supplies power to the MCU through a power supply control chip; the MCU is embedded with a Bluetooth AoA positioning algorithm for calculating the azimuth and distance of the Bluetooth AoA positioning signal, the MCU is connected to the data storage unit and the attitude sensor through a port, and the MCU is also connected to the combined antenna through a Bluetooth chip;

[0017] The combined antenna includes an omnidirectional main antenna and several antenna boards, on which a 2.4G band microstrip line antenna, a radio frequency channel switching chip, an IPEX radio frequency interface and several power supply and signal pins are arranged, and the omnidirectional main antenna is connected to the IPEX radio frequency interface of the corresponding antenna board.

[0018] A portable positioning method based on Bluetooth AOA positioning comprises the following steps:

[0019] 1) Connect the mobile terminal to the portable Bluetooth positioning base station and send the Bluetooth terminal device information required for positioning to it;

[0020] 2) The portable Bluetooth positioning base station performs Bluetooth positioning scanning through the omnidirectional main antenna. After scanning the Bluetooth AoA positioning signal sent by the target Bluetooth terminal device, the phase data of the Bluetooth AoA positioning signal is collected through the antenna board and sent to the MCU;

[0021] 3) The phase data is solved by the MCU's Bluetooth AoA positioning algorithm to obtain the azimuth and distance information of the target Bluetooth terminal device, and is sent to the mobile terminal in combination with the attitude data collected by the attitude sensor;

[0022] 4) After receiving the data from the portable Bluetooth positioning base station, the mobile terminal converts the azimuth by comparing its own posture data, and displays the position information of the Bluetooth terminal device relative to itself on the interface.

[0023] Furthermore, the calculation process of the azimuth of the Bluetooth terminal device in step 3) is as follows:

[0024] 3.1) Separate all phase data according to the antenna board where they are located;

[0025] 3.2) Use the phase data to calculate the average strength of the signal received by each antenna panel, and sort them according to the average signal strength;

[0026] 3.3) Use the MUSIC algorithm to independently calculate the azimuth angles of all antenna panels;

[0027] 3.4) Determine the azimuth angle calculated by the antenna board with the largest average strength and the antenna detection angle; when the angle is less than or equal to 20°, proceed to step 3.5); when the angle is greater than 20°, proceed to step 3.6);

[0028] 3.5) Substitute the phase data of the antenna panel with the largest average strength and its two adjacent antenna panels into formula (1) and formula (2);

[0029]

[0030] d=[n 1 ·x 1 , n 1 ·y 1 , n 2 ·x 2 , n 2 ·y 2 , n 3 ·x 3 , n 3 ·y 3 ] T (2)

[0031] 3.6) Substitute the phase data of the antenna panel with the largest average strength and the adjacent antenna panel whose signal is directed to one side into formula (3) and formula (4);

[0032]

[0033] d=[n 1 ·x 1 , n 1 ·y 1 , n 2 ·x 2 , n 2 ·y 2 ]T (4)

[0034] 3.7) Using formula (5), equations (6) and (7), the solution vector m is calculated. The first two digits of the solution vector m are used as the direction vector of the signal azimuth as the final output of the algorithm.

[0035] m=(G T G) -1 G T d (5)

[0036]

[0037]

[0038] When performing continuous positioning, the output azimuth data will be brought into the Kalman filter equation for optimization;

[0039] In the above formula, n i is the average strength of the signal received by each antenna panel, u xi and u yi is the direction vector of the azimuth relative to the plane coordinate system where the portable Bluetooth positioning base station is located, x 1 and 1 is the coordinate point of the center point of the antenna board relative to the plane coordinate system where the portable Bluetooth positioning base station is located, m is the solution vector of equation group (6) and equation group (7), formula (1) and formula (2) are the solution matrices constructed by equation group (6), and formula (3) and formula (4) are the solution matrices constructed by equation group (7).

[0040] Furthermore, the calculation process of the distance of the Bluetooth terminal device in step 3) is as follows:

[0041] The signal RSSI obtained by the omnidirectional main antenna is calculated based on the logarithmic path loss model to obtain the distance d between the Bluetooth terminal device and the portable Bluetooth positioning base station;

[0042] The logarithmic path loss model is shown in formula (8):

[0043]

[0044] Among them, d 0 is the standard reference distance, P 0 The distance from the antenna is d 0 The RSSI value of the signal collected by the signal source; α is the path loss index, which ranges from 1.6 to 1.8 and is configured after testing according to the actual scenario;

[0045] When performing continuous positioning, the distance data will be brought into the Kalman filter equation for optimization.

[0046] In summary, the present invention has the following beneficial effects:

[0047] By using a portable Bluetooth positioning base station and a mobile terminal that can communicate with it, the positioning of Bluetooth positioning terminal devices can be achieved in outdoor scenarios where there is no fixed positioning base station. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 It is a schematic diagram of the portable positioning system based on Bluetooth AOA positioning described in the present invention.

[0049] Figure 2 It is a schematic diagram of the portable Bluetooth positioning base station described in the present invention.

[0050] Figure 3 It is a flow chart of the portable positioning method based on Bluetooth AOA positioning described in the present invention.

[0051] Figure 4 It is a diagram of the calculation process of the azimuth angle of the Bluetooth AoA positioning signal described in the present invention. DETAILED DESCRIPTION

[0052] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further described below in conjunction with illustrations and specific embodiments.

[0053] like Figure 1 Hezhi Figure 4 As shown, the present invention proposes a portable positioning system based on Bluetooth AOA positioning, comprising:

[0054] A Bluetooth terminal device, which is used to periodically send Bluetooth AoA positioning signals;

[0055] A portable Bluetooth positioning base station, which is used to receive Bluetooth AoA positioning signals and calculate the azimuth and distance of the received Bluetooth AoA positioning signals through an embedded Bluetooth AoA positioning algorithm;

[0056] The mobile terminal is used to communicate with the portable Bluetooth positioning base station, send the information of the Bluetooth terminal device to be located to the portable Bluetooth positioning base station, and receive and display the angle and distance information of the Bluetooth terminal device fed back by the portable Bluetooth positioning base station.

[0057] Example

[0058] A portable positioning system based on Bluetooth AOA positioning consists of the following three functional units:

[0059] 1) Bluetooth terminal device: powered by battery. The Bluetooth chip used supports Bluetooth 5.1 and above. Installed on the asset to be tracked. It will periodically send Bluetooth AoA positioning signal broadcasts. It will adjust the broadcast field and broadcast period according to the motion state (stationary or moving) detected by the acceleration sensor.

[0060] 2) Portable Bluetooth positioning base station: The positioning base station hardware is as follows: Figure 2 As shown in the figure, it is equipped with a rechargeable battery pack, a high-performance MCU, a Bluetooth chip that supports Bluetooth 5.1 and above protocols, a 9-axis IMU attitude sensor, and a combined antenna hardware (including 1 omnidirectional antenna and 4 3*1 antenna boards). The high-performance MCU is burned with an embedded application containing the Bluetooth AoA positioning algorithm to calculate the azimuth and distance of the Bluetooth positioning signal. The antenna board ( Figure 1 ) The board has three 2.4G band microstrip antennas, a 1-to-4 RF channel switching chip, two IPEX RF interfaces, and four power supply and signal pins. The omnidirectional antenna is connected to the IPEX RF interface of the specified antenna board.

[0061] Smartphone: With Bluetooth function, installed with mobile phone APP for positioning base station configuration and result display. Connect to portable positioning base station via Bluetooth. Send the terminal device information to be positioned to the portable positioning base station. After receiving the terminal device angle and distance information calculated by the portable positioning base station, display it on the APP interface.

[0062] A portable positioning method based on Bluetooth AOA positioning comprises the following steps:

[0063] 1) Connect the mobile terminal to the portable Bluetooth positioning base station and send the Bluetooth terminal device information required for positioning to it;

[0064] 2) The portable Bluetooth positioning base station performs Bluetooth positioning scanning through the omnidirectional main antenna. After scanning the Bluetooth AoA positioning signal sent by the target Bluetooth terminal device, the phase data of the Bluetooth AoA positioning signal is collected through the antenna board and sent to the MCU;

[0065] 3) The phase data is solved by the MCU's Bluetooth AoA positioning algorithm to obtain the azimuth and distance information of the target Bluetooth terminal device, and is sent to the mobile terminal in combination with the attitude data collected by the attitude sensor;

[0066] 4) After receiving the data from the portable Bluetooth positioning base station, the mobile terminal converts the azimuth by comparing its own posture data, and displays the position information of the Bluetooth terminal device relative to itself on the interface.

[0067] The calculation process of the azimuth of the Bluetooth terminal device in step 3) is as follows:

[0068] 3.1) Separate all phase data according to the antenna board where they are located;

[0069] 3.2) Use the phase data to calculate the average strength of the signal received by each antenna panel, and sort them according to the average signal strength;

[0070] 3.3) Use the MUSIC algorithm to independently calculate the azimuth angles of all antenna panels;

[0071] 3.4) Determine the azimuth angle calculated by the antenna board with the largest average strength and the antenna detection angle; when the angle is less than or equal to 20°, proceed to step 3.5); when the angle is greater than 20°, proceed to step 3.6);

[0072] 3.5) Substitute the phase data of the antenna panel with the largest average strength and its two adjacent antenna panels into formula (1) and formula (2);

[0073]

[0074] d=[n 1 ·x 1 , n 1 ·y 1 , n 2 ·x 2 , n 2 ·y 2 , n 3 ·x 3 , n 3 ·y 3 ] T (2)

[0075] 3.6) Substitute the phase data of the antenna panel with the largest average strength and the adjacent antenna panel whose signal is directed to one side into formula (3) and formula (4);

[0076]

[0077] d=[n 1 ·x 1 , n 1 ·y 1 , n 2 ·x 2 , n 2 ·y 2 ] T (4)

[0078] 3.7) Using formula (5), equations (6) and (7), the solution vector m is calculated. The first two digits of the solution vector m are used as the direction vector of the signal azimuth as the final output of the algorithm.

[0079] m=(G T G) -1 G T d (5)

[0080]

[0081]

[0082] When performing continuous positioning, the output azimuth data will be brought into the Kalman filter equation for optimization;

[0083] In the above formula, n i is the average strength of the signal received by each antenna panel, u xi and u yi is the direction vector of the azimuth relative to the plane coordinate system where the portable Bluetooth positioning base station is located, x 1 and 1 is the coordinate point of the center point of the antenna board relative to the plane coordinate system where the portable Bluetooth positioning base station is located, m is the solution vector of equation group (6) and equation group (7), formula (1) and formula (2) are the solution matrices constructed by equation group (6), and formula (3) and formula (4) are the solution matrices constructed by equation group (7).

[0084] The calculation process of the distance of the Bluetooth terminal device in step 3) is as follows:

[0085] The signal RSSI obtained by the omnidirectional main antenna is calculated based on the logarithmic path loss model to obtain the distance d between the Bluetooth terminal device and the portable Bluetooth positioning base station;

[0086] The logarithmic path loss model is shown in formula (8):

[0087]

[0088] Among them, d 0 is the standard reference distance, P 0 The distance from the antenna is d 0 The RSSI value of the signal collected by the signal source; α is the path loss index, which ranges from 1.6 to 1.8 and is configured after testing according to the actual scenario;

[0089] When performing continuous positioning, the distance data will be brought into the Kalman filter equation for optimization.

[0090] In this document, the directions or positional relationships indicated by terms such as "up", "down", "front", "back", "left", "right", "top", "bottom", "inside", "outside", "vertical", and "horizontal" are based on the directions or positional relationships shown in the accompanying drawings and are only for the clarity of expressing the technical solutions and the convenience of description, and therefore should not be understood as limitations of the present invention.

[0091] In this document, the terms "comprises," "comprising," or any other variations thereof, are intended to cover a non-exclusive inclusion of elements other than those listed and may also include additional elements not expressly listed.

[0092] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. The present invention may be subject to various changes and improvements without departing from the spirit and scope of the present invention. These changes and improvements fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A portable positioning system based on Bluetooth AOA positioning, characterized in that: include A Bluetooth terminal device, which is used to periodically send Bluetooth AoA positioning signals; A portable Bluetooth positioning base station, which is used to receive Bluetooth AoA positioning signals and calculate the azimuth and distance of the received Bluetooth AoA positioning signals through a self-developed embedded Bluetooth AoA positioning algorithm; The mobile terminal is used to communicate with the portable Bluetooth positioning base station, send the information of the Bluetooth terminal device to be located to the portable Bluetooth positioning base station, and receive and display the angle and distance information of the Bluetooth terminal device fed back by the portable Bluetooth positioning base station.

2. The portable positioning system based on Bluetooth AOA positioning according to claim 1, characterized in that: The portable Bluetooth positioning base station includes a power module, an MCU, a Bluetooth chip, a posture sensor and a combined antenna; The power module includes a rechargeable battery pack and a DC adapter, which supplies power to the MCU through a power supply control chip; the MCU is embedded with a Bluetooth AoA positioning algorithm for calculating the azimuth and distance of the Bluetooth AoA positioning signal, the MCU is connected to the data storage unit and the attitude sensor through a port, and the MCU is also connected to the combined antenna through a Bluetooth chip; The combined antenna includes an omnidirectional main antenna and several antenna boards, on which a 2.4G band microstrip line antenna, a radio frequency channel switching chip, an IPEX radio frequency interface and several power supply and signal pins are arranged, and the omnidirectional main antenna is connected to the IPEX radio frequency interface of the corresponding antenna board.

3. A portable positioning method based on Bluetooth AOA positioning, comprising a portable positioning system as claimed in claim 1 or 2, characterized in that: The steps include: 1) Connect the mobile terminal to the portable Bluetooth positioning base station and send the Bluetooth terminal device information required for positioning to it; 2) The portable Bluetooth positioning base station performs Bluetooth positioning scanning through the omnidirectional main antenna. After scanning the Bluetooth AoA positioning signal sent by the target Bluetooth terminal device, the phase data of the Bluetooth AoA positioning signal is collected through the antenna board and sent to the MCU; 3) The phase data is solved by the MCU's Bluetooth AoA positioning algorithm to obtain the azimuth and distance information of the target Bluetooth terminal device, and is sent to the mobile terminal in combination with the attitude data collected by the attitude sensor; 4) After receiving the data from the portable Bluetooth positioning base station, the mobile terminal converts the azimuth by comparing its own posture data, and displays the position information of the Bluetooth terminal device relative to itself on the interface.

4. The portable positioning method based on Bluetooth AOA positioning according to claim 3 is characterized in that: The calculation process of the azimuth of the Bluetooth terminal device in step 3) is as follows: 3.1) Separate all phase data according to the antenna board where they are located; 3.2) Use the phase data to calculate the average strength of the signal received by each antenna panel, and sort them according to the average signal strength; 3.3) Use the MUSIC algorithm to independently calculate the azimuth angles of all antenna panels; 3.4) Determine the azimuth angle calculated by the antenna board with the largest average strength and the antenna detection angle; when the angle is less than or equal to 20°, proceed to step 3.5); when the angle is greater than 20°, proceed to step 3.6); 3.5) Substitute the phase data of the antenna panel with the largest average strength and its two adjacent antenna panels into formula (1) and formula (2); <h2 style=";text-align:left;direction:ltr">d = [n1 x1, n1 y1, n2 x2, n2 y2, n3 x3, n3 y3]<h2 style=";text-align:left;direction:ltr"> T <h2 style=";text-align:left;direction:ltr"> (2) 3.6) Substitute the phase data of the antenna panel with the largest average strength and the adjacent antenna panel whose signal is directed to one side into formula (3) and formula (4); <h2 style=";text-align:left;direction:ltr">d = [n1 x1, n1 y1, n2 x2, n2 y2]<h2 style=";text-align:left;direction:ltr"> T <h2 style=";text-align:left;direction:ltr"> (4) 3.7) Using formula (5), equations (6) and (7), the solution vector m is calculated. The first two digits of the solution vector m are used as the direction vector of the signal azimuth as the final output of the algorithm. m=(G T G) -1 G T d (5) When performing continuous positioning, the output azimuth data will be brought into the Kalman filter equation for optimization; In the above formula, n i is the average strength of the signal received by each antenna panel, u xi and u yi is the direction vector of the azimuth angle relative to the plane coordinate system where the portable Bluetooth positioning base station is located, x1 and y1 are the coordinate points of the center point of the antenna board relative to the plane coordinate system where the portable Bluetooth positioning base station is located, m is the solution vector of equation group (6) and equation group (7), formula (1) and formula (2) are the solution matrices constructed by equation group (6), and formula (3) and formula (4) are the solution matrices constructed by equation group (7).

5. The portable positioning method based on Bluetooth AOA positioning according to claim 3 is characterized in that: The calculation process of the distance of the Bluetooth terminal device in step 3) is as follows: The signal RSSI obtained by the omnidirectional main antenna is calculated based on the logarithmic path loss model to obtain the distance d between the Bluetooth terminal device and the portable Bluetooth positioning base station; The logarithmic path loss model is shown in formula (8): Among them, d0 is the standard reference distance, P0 is the RSSI value of the signal collected by the signal source at a distance d0 from the antenna; α is the path loss index, which ranges from 1.6 to 1.8 and is configured after testing according to the actual scenario; When performing continuous positioning, the distance data will be brought into the Kalman filter equation for optimization.

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