CN110376548A - A kind of multi-target orientation method and system - Google Patents

Abstract

The invention discloses a multi-target positioning method, which includes responding to N targets entering the monitoring area, collecting signals received by the targets from anchor nodes in the monitoring area; taking the anchor nodes corresponding to the strongest first N signals as cluster centers, and adopting network The grid clustering algorithm divides the monitoring area into N grids; in each grid, the position of the target is calculated according to the anchor node signal received by the target. The present invention uses several anchor nodes with the strongest signals as cluster points, uses a grid clustering algorithm to divide the monitoring area into multiple grids, and uses different methods to calculate Target position, accurate positioning, applicable to various scenarios, and has good promotion.

Description

A multi-target positioning method and system

technical field

The invention relates to a multi-target positioning method and system, and belongs to the technical field of Internet of Things positioning.

Background technique

With the development of science and technology, positioning technology has received extensive attention. Outdoor positioning technology mainly uses the Global Positioning System (GPS) or Beidou positioning system to locate the target. Indoors, the above positioning systems are difficult to receive satellite signals and lose their positioning. Accuracy; therefore, there is an urgent need for a positioning method with higher accuracy indoors.

Contents of the invention

The present invention provides a multi-target positioning method and system, which solves the above-mentioned problems existing in the existing indoor positioning.

In order to solve the problems of the technologies described above, the technical solution adopted in the present invention is:

A multi-target localization method comprising,

In response to N targets entering the monitoring area, collecting signals received by the targets from anchor nodes in the monitoring area;

The anchor nodes corresponding to the strongest first N signals are used as cluster centers, and the monitoring area is divided into N grids using a grid clustering algorithm;

In each grid, the position of the target is calculated according to the anchor node signal received by the target.

The anchor node sends its location information and RSSI value to the target.

In the grid clustering algorithm, the N cluster centers remain unchanged.

In response to the target being located in the grid and receiving more than or equal to three anchor node signals, the weighted centroid method is used to solve the target position;

In response to the target being located in the grid and receiving two anchor node signals, draw a ball with the two anchor node positions as the center of the sphere and the distance to the target as the radius; if the two spheres are tangent, the target is located on the line where the centers of the two spheres are located and the intersection point of the tangent line where the tangent point is located; if the two balls intersect, use the law of cosines and the positions of the two anchor nodes to solve the target position;

In response to the target being located in the grid and receiving one anchor node signal, the anchor node and inertial navigation data are used to perform positioning according to the method of receiving two anchor node signals.

In response to the fact that the target is located at the junction of adjacent grids, the strongest signals received by the target in four different directions are screened out. According to the anchor node positions of the four strongest signals, the weighted centroid method is used to solve the target position.

In response to the target being located outside the monitoring area, locating the target using already located common nodes at the edge of the monitoring area;

If there are more than three common nodes communicating with the target, the weighted centroid method is used to solve the target position;

If there are two common nodes communicating with the target, then the law of cosines and the positions of the two common nodes solve the target position;

If there is a common node communicating with the target, then use the common node and inertial navigation data to locate according to the method of receiving signals from two common nodes.

A multi-target positioning system comprising,

Signal collection module: in response to N targets entering the monitoring area, collecting signals received by the target from the monitoring area anchor node;

Grid clustering module: use the anchor nodes corresponding to the strongest first N signals as cluster centers, and use grid clustering algorithm to divide the monitoring area into N grids;

Target calculation module: in each grid, calculate the position of the target according to the anchor node signal received by the target.

The target calculation module includes a first calculation module, a second calculation module and a third calculation module;

The first calculation module: in response to the target being located in the grid and receiving more than or equal to three anchor node signals, the weighted centroid method is used to solve the target position;

The second calculation module: in response to the target being located in the grid and receiving two anchor node signals, draw a ball with the two anchor node positions as the center of the sphere and the distance to the target as the radius; if the two spheres are tangent, the target is located at two At the intersection of the straight line where the center of the ball is located and the tangent where the tangent point is located; if the two balls intersect, use the law of cosines and the positions of two anchor nodes to solve the target position;

The third calculation module: in response to the target being located in the grid and receiving an anchor node signal, the anchor node and inertial navigation data are used to perform positioning according to the method of receiving two anchor node signals.

The target computing module includes a fourth computing module;

The fourth calculation module: in response to the target being located at the junction of adjacent grids, filter out the strongest signals received by the target in four different directions, and use the weighted centroid method to solve the target position according to the anchor node positions of the four strongest signals .

The target computing module includes a fifth computing module;

The fifth calculation module: in response to the target being located outside the monitoring area, using the already located common nodes on the edge of the monitoring area to locate the target;

If there are more than three common nodes communicating with the target, the weighted centroid method is used to solve the target position;

If there are two common nodes communicating with the target, then the law of cosines and the positions of the two common nodes solve the target position;

If there is a common node communicating with the target, then use the common node and inertial navigation data to locate according to the method of receiving signals from two common nodes.

The beneficial effects achieved by the present invention: the present invention uses several anchor nodes with the strongest signals as cluster points, and uses a grid clustering algorithm to divide the monitoring area into multiple grids. The number of signals, using different methods to calculate the target position, accurate positioning, suitable for various scenarios, and has good scalability.

Description of drawings

Fig. 1 is a flowchart of the present invention;

Figure 2 shows the triangle formed by the target and two anchor nodes.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings. The following examples are only used to more clearly illustrate the technical solutions of the present invention, but cannot limit the protection scope of the present invention with this.

As shown in Figure 1, a multi-target positioning method. Before positioning, deploy a positioning network and deploy multiple anchor nodes in the monitoring area. When N targets enter the monitoring area, the anchor nodes send signals to the targets. The signals include The anchor node's own location information and RSSI value, the server communicates with the target, and performs multi-target positioning. The specific method is shown in Figure 1, including:

Step 1, in response to N targets entering the monitoring area, collect the signal received by the target from the anchor node in the monitoring area.

Step 2, sort all signal strengths from strong to weak, and extract the strongest top N signals.

Step 3: Use the anchor nodes corresponding to the strongest top N signals as the cluster centers, and use the grid clustering algorithm to divide the monitoring area into N grids; among them, the N cluster centers in the grid clustering algorithm remain unchanged , not only simplifies the calculation process, but also utilizes the position information of the N anchor nodes closest to the target, which can realize multi-target positioning in one scan.

Step 3, in each grid, calculate the position of the target according to the anchor node signal received by the target.

The position of the target in the grid can be divided into the following situations:

1. The target is located inside the grid;

The target receives more than or equal to three anchor node signals, converts the RSSI data into distance information, then draws a ball with the anchor node position as the center and the distance R _i between the target and the i-th anchor node as the radius, and uses the weighted centroid method to solve the target position , the specific formula is as follows:

Among them, (x ₀ , y ₀ , z ₀ ) are the target coordinates, ( _xi , y _i , _zi ) are the coordinates of the i-th anchor node, i1 is the number of anchor node signals received,

The target receives the signals of two anchor nodes, draw a ball with the position of the two anchor nodes as the center of the sphere, and the distance to the target as the radius. The two spheres have the following two situations:

A. If two balls are tangent, we can get,

Among them, (x ₁ , y ₁ , z ₁ ) is the coordinates of the first anchor node, (x ₂ , y ₂ , z ₂ ) is the coordinates of the second anchor node, and R ₁ is the distance from the first anchor node to the target , R ₂ is the distance from the second anchor node to the target;

From the R ₁ and R ₂ formulas,

Formula (4) can be further simplified as:

ax ₀ +by ₀ +cz ₀ =d (5)

where -2(x ₁ -x ₂ )=a, -2(y ₁ -y ₂ )=b, -2(z ₁ -z ₂ )=c,

According to the position coordinates of the two anchor nodes, the linear equation can be obtained as:

The target is located at the intersection of the straight line where the centers of the two balls are located and the tangent where the tangent point is located, then the calculation formula for the target position is:

Among them, k is the slope.

B. If the two balls intersect, the target and the two anchor nodes can form a triangle. Use the law of cosines and the positions of the two anchor nodes to solve the target position. The specific formula is as follows:

Among them, D is the distance between the two centers of spheres, and α1 is the angle between the line connecting the _first anchor node to the target and the line connecting the two anchor nodes.

The target receives an anchor node signal, and uses the anchor node and inertial navigation data to perform positioning according to the method of receiving two anchor node signals.

2. The target is located at the junction of adjacent grids. At this time, the target receives two anchor node signals with similar strengths. When the target crosses the grid, the dynamic virtual grid method is used, that is, when the target reaches the grid boundary, the target is screened out The strongest signals received from four different orientations (generally the four orientations of up, down, left, and right), recombine the anchor nodes of the four strongest signals into a new grid, and according to the positions of the anchor nodes of the four strongest signals, The weighted centroid method is used to solve the target position.

3. In response to the target being located outside the monitoring area, use the already located common nodes on the edge of the monitoring area to locate the target: if there are more than three common nodes communicating with the target, use the weighted centroid method to solve the target position; if there are two common nodes communicating with the target For communication, the cosine law and the positions of two common nodes are used to solve the target position; if there is a common node communicating with the target, the common node and inertial navigation data are used to locate the target according to the method of receiving the signals of the two common nodes.

Using the above method to locate multiple targets, and comparing the positioning results with the measured structure, it is found that the accuracy of the positioning results of this method can reach centimeter level.

In summary, the above method uses several anchor nodes with the strongest signal as cluster points, and uses a grid clustering algorithm to divide the monitoring area into multiple grids. According to the grid position of the target and the number of anchor node signals received, different The method calculates the target position with accurate positioning, is applicable to various scenarios, and has good generalization.

A multi-target positioning system comprising:

Signal acquisition module: in response to N targets entering the monitoring area, collecting signals received by the targets from the anchor nodes in the monitoring area.

Grid clustering module: use the anchor nodes corresponding to the strongest top N signals as the cluster centers, and use the grid clustering algorithm to divide the monitoring area into N grids.

Target calculation module: in each grid, calculate the position of the target according to the anchor node signal received by the target.

The target computing module includes a first computing module, a second computing module, a third computing module, a fourth computing module and a fifth computing module.

The first calculation module: in response to the target being located in the grid and receiving more than or equal to three anchor node signals, the weighted centroid method is used to solve the target position.

The second calculation module: in response to the target being located in the grid and receiving two anchor node signals, draw a ball with the two anchor node positions as the center of the sphere and the distance to the target as the radius; if the two spheres are tangent, the target is located at two At the intersection of the straight line where the center of the sphere is located and the tangent where the tangent point is located; if the two spheres intersect, use the law of cosines and the positions of the two anchor nodes to find the target position.

The third calculation module: in response to the target being located in the grid and receiving an anchor node signal, the anchor node and inertial navigation data are used to perform positioning according to the method of receiving two anchor node signals.

The fourth calculation module: in response to the target being located at the junction of adjacent grids, filter out the strongest signals received by the target in four different directions, and use the weighted centroid method to solve the target position according to the anchor node positions of the four strongest signals .

The fifth calculation module: in response to the target being located outside the monitoring area, use the already located common nodes on the edge of the monitoring area to locate the target; if there are more than three common nodes communicating with the target, use the weighted centroid method to solve the target position; if there are two common nodes If the node communicates with the target, the cosine law and two common node positions can solve the target position; if there is a common node communicating with the target, then the common node and the inertial navigation data are used to locate the position according to the method of receiving the signals of the two common nodes.

A computer-readable storage medium storing one or more programs comprising instructions that, when executed by a computing device, cause the computing device to perform a multi-object location method.

A computing device comprising one or more processors, memory, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the One or more programs include instructions for performing the multi-object localization method.

Those skilled in the art should understand that the embodiments of the present application may be provided as methods, systems, or computer program products. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It should be understood that each process and/or block in the flowchart and/or block diagrams, and a combination of processes and/or blocks in the flowchart and/or block diagrams can be realized by computer program instructions. These computer program instructions may be provided to a general purpose computer, special purpose computer, embedded processor, or processor of other programmable data processing equipment to produce a machine such that the instructions executed by the processor of the computer or other programmable data processing equipment produce a An apparatus for realizing the functions specified in one or more procedures of the flowchart and/or one or more blocks of the block diagram.

These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing apparatus to operate in a specific manner, such that the instructions stored in the computer-readable memory produce an article of manufacture comprising instruction means, the instructions The device realizes the function specified in one or more procedures of the flowchart and/or one or more blocks of the block diagram.

These computer program instructions can also be loaded onto a computer or other programmable data processing device, causing a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process, thereby The instructions provide steps for implementing the functions specified in the flow chart or blocks of the flowchart and/or the block or blocks of the block diagrams.

The above are only embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention are included in the pending application of the present invention. within the scope of the claims.

Claims (10)

1. A multi-target positioning method, characterized in that: comprising, In response to N targets entering the monitoring area, collecting signals received by the targets from anchor nodes in the monitoring area; The anchor nodes corresponding to the strongest top N signals are used as cluster centers, and the monitoring area is divided into N grids by using a grid clustering algorithm; In each grid, the position of the target is calculated according to the anchor node signal received by the target. 2. A multi-target positioning method according to claim 1, characterized in that: the anchor node sends its own position information and RSSI value to the target. 3. A multi-target positioning method according to claim 1, characterized in that: the N cluster centers remain unchanged in the grid clustering algorithm. 4. A kind of multi-target positioning method according to claim 1, characterized in that: in response to the target being located in the grid and receiving more than or equal to three anchor node signals, the weighted centroid method is used to solve the target position; In response to the target being located in the grid and receiving two anchor node signals, draw a ball with the two anchor node positions as the center of the sphere and the distance to the target as the radius; if the two spheres are tangent, the target is located on the line where the centers of the two spheres are located and the intersection point of the tangent line where the tangent point is located; if the two balls intersect, use the law of cosines and the positions of the two anchor nodes to solve the target position; In response to the target being located in the grid and receiving one anchor node signal, the anchor node and inertial navigation data are used to perform positioning according to the method of receiving two anchor node signals. 5. A kind of multi-target positioning method according to claim 1, characterized in that: in response to the target being located at the junction of adjacent grids, the strongest signals of four different orientations received by the target are screened out, and according to the four The anchor node position of the strongest signal, using the weighted centroid method to solve the target position. 6. A kind of multi-target positioning method according to claim 1, characterized in that: in response to the target being located outside the monitoring area, utilizing the common nodes on the edge of the monitoring area already located to locate the target; If there are more than three common nodes communicating with the target, the weighted centroid method is used to solve the target position; If there are two common nodes communicating with the target, then the law of cosines and the positions of the two common nodes solve for the target position; If there is an ordinary node communicating with the target, the ordinary node and the inertial navigation data are used to locate according to the method of receiving the signals of two ordinary nodes. 7. A multi-target positioning system, characterized in that: comprising, Signal acquisition module: in response to N targets entering the monitoring area, collecting signals received by the targets from the anchor nodes in the monitoring area; Grid clustering module: use the anchor nodes corresponding to the strongest top N signals as the cluster center, and use the grid clustering algorithm to divide the monitoring area into N grids; Target calculation module: in each grid, calculate the position of the target according to the anchor node signal received by the target. 8. A kind of multi-target positioning system according to claim 7, characterized in that: the target calculation module comprises a first calculation module, a second calculation module and a third calculation module; The first calculation module: in response to the target being located in the grid and receiving more than or equal to three anchor node signals, the weighted centroid method is used to solve the target position; The second calculation module: in response to the target being located in the grid and receiving two anchor node signals, draw a ball with the two anchor node positions as the center of the sphere and the distance to the target as the radius; if the two spheres are tangent, the target is located at two At the intersection of the straight line where the center of the ball is located and the tangent where the tangent point is located; if the two balls intersect, use the law of cosines and the positions of two anchor nodes to solve the target position; The third calculation module: in response to the target being located in the grid and receiving one anchor node signal, using the anchor node and the inertial navigation data to perform positioning according to the method of receiving two anchor node signals. 9. A multi-target positioning system according to claim 7, characterized in that: the target calculation module includes a fourth calculation module; The fourth calculation module: in response to the target being located at the junction of adjacent grids, filter out the strongest signals received by the target in four different directions, and use the weighted centroid method to solve the target position according to the anchor node positions of the four strongest signals . 10. A multi-target positioning system according to claim 7, characterized in that: the target calculation module includes a fifth calculation module; The fifth calculation module: in response to the target being located at the edge of the monitoring area, using the already located common nodes at the edge of the monitoring area to locate the target; If there are more than three common nodes communicating with the target, the weighted centroid method is used to solve the target position; If there are two common nodes communicating with the target, then the law of cosines and the positions of the two common nodes solve for the target position; If there is an ordinary node communicating with the target, the ordinary node and the inertial navigation data are used to locate according to the method of receiving the signals of two ordinary nodes.