CN109218961B - Multi-station cooperative interference positioning method and system based on virtual nodes - Google Patents

Abstract

The invention discloses a multi-station cooperative interference positioning method and a system based on virtual nodes.A first three nodes of RSSI (received signal strength indicator) values of signals of a signal source to be positioned received by a monitoring node are used as positioning nodes according to the sequence of the RSSI values, the positioning node with the maximum RSSI value is used as a reference node, and the coordinates of a second/third virtual node are determined according to the coordinates of the second/third node, the transmission time difference between the second/third node and the reference node to reach the signal source to be positioned and the direction of the signals received by the second/third node; and constructing a positioning combination according to the reference node, one of the second node and the second virtual node, and one of the third node and the third virtual node, calculating initial positioning coordinates of each combination, and calculating the positioning coordinates of the signal source to be positioned according to the initial positioning coordinates and the corresponding weighting coefficients. By means of constructing the virtual nodes, node combinations of cooperative positioning are enriched, positioning errors caused by node distribution are reduced, and positioning accuracy is improved by means of weighting of positioning results of different cooperative combinations based on RSSI values.

Description

A method and system for multi-station cooperative interference localization based on virtual nodes

technical field

The present invention relates to the field of wireless communication, in particular to a method and system for multi-station cooperative interference positioning based on virtual nodes.

Background technique

The basic technologies used in passive positioning mainly include time difference (TDOA) positioning technology, angle measurement (AOA) cross positioning technology, and Doppler frequency difference (FDOA) positioning technology. TDOA positioning technology is more widely used because it can obtain higher positioning accuracy, at the same time, it has lower requirements on the receiving system and is easy to form a network. The TDOA passive positioning system is usually a distributed positioning system composed of multiple monitoring sensors, and the multiple monitoring sensors work together, which is better than single-station monitoring in terms of positioning accuracy and positioning performance. The TDOA positioning calculation process is mainly divided into two parts, time difference calculation and positioning result calculation. The time difference calculation mainly considers the time difference between the signal source and the two monitoring sensors according to the received signal; the positioning result calculation mainly considers establishing the positioning equation and solving the positioning result according to the time difference.

However, the existing positioning algorithms mainly have the following problems: the selection basis of the reference node is not given; the calculation of the positioning result does not consider the influence of the RSSI (Received Signal Strength Indication, that is, the received signal strength indication) received by the cooperative nodes; the current algorithm The selection of cooperative nodes is based on the node coordinates of the actual deployment, but in the actual deployment, the deployment of monitoring device nodes is irregular, so that the accuracy of the positioning results is not high.

SUMMARY OF THE INVENTION

Therefore, the present invention provides a virtual node-based multi-station cooperative interference positioning method and system, which overcomes the problem of low accuracy of node coordinate positioning based on actual deployment in the prior art.

A method for locating multi-station cooperative interference based on virtual nodes provided by an embodiment of the present invention includes the following steps: acquiring three nodes in a monitoring node as positioning nodes, which are a reference node, a second node, and a third node; calculating the The transmission time difference between the second node and the reference node reaching the signal source to be located, the transmission time difference between the third node and the reference node reaching the signal source to be located; according to the coordinates of the second node, the second node and the Determine the coordinates of the second virtual node according to the transmission time difference of the reference node reaching the signal source to be located and the direction of the signal received by the second node; according to the coordinates of the third node, the arrival of the third node and the reference node The transmission time difference of the signal source to be located and the direction in which the third node receives the signal, determine the coordinates of the third virtual node; according to the reference node, one of the second node and the second virtual node, the third node and the One of the third virtual nodes constructs a positioning combination; calculates the initial positioning coordinates of the to-be-located signal source corresponding to each positioning combination; calculates the corresponding initial position of each positioning combination according to the RSSI value of the to-be-located signal source signal received by each positioning node Weighting coefficients of the positioning coordinates; calculating the positioning coordinates of the signal source to be positioned according to the initial positioning coordinates and the corresponding weighting coefficients.

Preferably, the step of acquiring three nodes in the monitoring nodes as positioning nodes includes: acquiring the first three nodes in the monitoring node that receive RSSI values of the signal source signals to be located in order of high and low order The node is used as the positioning node; the RSSI value of the signal source signal to be located to each of the positioning nodes is obtained respectively; the positioning node with the largest RSSI value is used as the reference node; the other two positioning nodes are respectively used as the first positioning node. The second node and the third node.

Preferably, the step of calculating the coordinates of the second virtual node is based on the coordinates of the second node, the transmission time difference between the second node and the reference node reaching the signal source to be located, and the direction in which the second node receives the signal , comprising: calculating the difference in the transmission distance between the second node and the reference node according to the transmission time difference between the second node and the reference node reaching the signal source to be located; The coordinates, the difference in the transmission distance between the second node and the reference node, and the direction in which the second node receives signals determine the coordinates of the second virtual node.

Preferably, the coordinates of the second virtual node are determined according to the coordinates of the second node, the transmission time difference between the second node and the reference node reaching the signal source to be located, and the direction in which the second node receives signals The step specifically includes: according to the wireless propagation loss calculation formula, respectively calculating the first transmission loss of the second node in the occlusion environment and the second transmission loss in the unobstructed environment; according to the second node and the reference node Calculate the first distance from the second node to the signal source to be located by the transmission time difference reaching the signal source to be located; according to the RSSI value of the second node, the first transmission loss, the first distance and the reference The distance between the node and the signal source to be located determines the RSSI difference between the RSSI value of the second node and the RSSI value of the second virtual node; according to the power of the signal source to be located, the second transmission loss and all The RSSI difference value calculates the second distance between the second node and the to-be-located signal source in an unobstructed environment; according to the distance between the reference node and the to-be-located signal source, the second distance and the The coordinates and the direction in which the second node receives the signal determine the coordinates of the second virtual node.

Preferably, the step of calculating the coordinates of the third virtual node according to the coordinates of the third node, the transmission time difference between the third node and the reference node reaching the signal source to be located, and the direction in which the third node receives signals , which specifically includes: calculating the difference between the transmission distances between the third node and the reference node according to the transmission time difference between the third node and the reference node reaching the signal source to be located; according to the third node The coordinates of the third virtual node are determined by the coordinates of the third node, the difference in the transmission distance between the third node and the reference node, and the direction in which the third node receives the signal.

Preferably, the step of calculating the coordinates of the third virtual node according to the coordinates of the third node, the transmission time difference between the third node and the reference node reaching the signal source to be located, and the direction in which the third node receives signals , which specifically includes: according to the wireless propagation loss calculation formula, respectively calculating the third transmission loss of the third node in the occlusion environment and the fourth transmission loss in the unobstructed environment; according to the third node and the reference node arrival to be determined The transmission time difference of the bit signal source calculates the third distance from the third node to the signal source to be located; according to the RSSI value of the third node, the third transmission loss, the third distance and the reference node and the The distance of the signal source to be located determines the RSSI difference between the RSSI value of the third node and the RSSI value of the third virtual node; according to the power of the signal source to be located, the fourth transmission loss and the RSSI The difference calculates the fourth distance between the third node and the to-be-located signal source in an unobstructed environment; according to the distance between the reference node and the to-be-located signal source, the fourth distance and the coordinates of the third node and The direction in which the third node receives the signal determines the coordinates of the third virtual node.

Preferably, the step of calculating the weighting coefficient of the corresponding initial positioning coordinates of the positioning combination according to the RSSI value that each positioning node receives the signal source signal to be positioned, specifically includes:

The average value of the RSSI values of each node in the positioning combination is calculated by the following formula:

Wherein, RSSI _i represents the average value of the RSSI values of each node in the ith positioning combination, RSSI _ij represents the RSSI value of the jth node in the ith positioning combination, and n represents the number of nodes in each combination;

The weighting coefficient corresponding to the positioning combination is calculated by the following formula:

Wherein, w _i represents the weighting coefficient of the ith positioning combination, RSSI _i represents the average value of the RSSI values of each node in the ith positioning combination, and N represents the number of positioning combinations.

Preferably, the step of calculating the positioning coordinates of the signal source to be located according to the initial positioning coordinates and the corresponding weighting coefficients, calculates the positioning coordinates of the signal source to be located by the following formula:

Wherein, _wi represents the weighting coefficient of the _ith positioning combination, L represents the positioning coordinates of the signal source signal to be located, and Li represents the initial positioning coordinates of the ith positioning combination.

An embodiment of the present invention further provides a virtual node-based multi-station cooperative interference positioning system, including: a positioning node acquisition module, configured to obtain three nodes in the monitoring nodes as positioning nodes, which are a reference node, a second node and a third node respectively. node; a transmission time difference acquisition module for calculating the transmission time difference between the second node and the reference node to the signal source to be located, and the transmission time difference between the third node and the reference node to the signal source to be located; the second virtual node The coordinate determination module is configured to determine the coordinate of the second virtual node according to the coordinates of the second node, the transmission time difference between the second node and the reference node reaching the signal source to be located, and the direction of the signal received by the second node. Coordinates; a third virtual node coordinate determination module, configured to, according to the coordinates of the third node, the transmission time difference between the third node and the reference node reaching the signal source to be located, and the direction in which the third node receives the signal, determining the coordinates of the third virtual node; a positioning combination building module for building a positioning combination according to the reference node, one of the second node and the second virtual node, and one of the third node and the third virtual node; The initial positioning coordinate calculation module is used to calculate the initial positioning coordinates of the to-be-located signal source corresponding to each of the positioning combinations; the weighting coefficient acquisition module is used to calculate the RSSI values of the signals of the to-be-located signal sources received by each positioning node respectively. The positioning combination corresponds to the weighting coefficient of the initial positioning coordinates; the positioning coordinate calculation module is configured to calculate the positioning coordinates of the to-be-located signal source according to the initial positioning coordinates and the corresponding weighting coefficients.

An embodiment of the present invention further provides a computer device, comprising: at least one processor, and a memory communicatively connected to the at least one processor, wherein the memory stores instructions executable by the at least one processor, The instructions are executed by the at least one processor, so that the at least one processor executes the above virtual node-based multi-station cooperative interference localization method.

An embodiment of the present invention further provides a computer-readable storage medium, where the computer-readable storage medium stores computer instructions, and the computer instructions are used to cause the computer to execute the above-mentioned virtual node-based multi-station cooperative interference positioning method.

The technical scheme of the present invention has the following advantages:

In the virtual node-based multi-station cooperative interference positioning method and system provided by the embodiment of the present invention, the monitoring nodes receive the three largest RSSI values of the signal source signal to be located as the positioning nodes, and the positioning nodes with the largest RSSI value are used as the reference nodes. Determine the coordinates of the second/third virtual node according to the coordinates of the second/third node, the transmission time difference between the second/third node and the reference node reaching the signal source to be located, and the direction of the signal received by the second/third node; according to the reference node, One of the second node and the second virtual node, and one of the third node and the third virtual node constructs a positioning combination, calculates the initial positioning coordinates of each combination, and calculates the signal to be positioned according to the initial positioning coordinates and the corresponding weighting coefficients. The location coordinates of the source. By constructing virtual nodes, the combination of nodes for co-location is enriched, the positioning error caused by node distribution is reduced, and the positioning accuracy is improved by using the weighting method of positioning results based on different cooperative combinations of RSSI values.

Description of drawings

In order to illustrate the specific embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the specific embodiments or the prior art. Obviously, the accompanying drawings in the following description The drawings are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative efforts.

1 is a flowchart of a specific embodiment of a virtual node-based multi-station cooperative interference positioning method provided in an embodiment of the present invention;

Fig. 2 is a flow chart of a specific example of determining a positioning node and a reference node in an embodiment of the present invention;

3 is a flow chart of a specific example of calculating the coordinates of the second virtual node in the embodiment of the present invention;

4 is a schematic diagram of constructing a virtual node in an embodiment of the present invention;

5 is a flowchart of another specific example of calculating the coordinates of the second virtual node in the embodiment of the present invention;

6 is a flow chart of a specific example of calculating the coordinates of the third virtual node in the embodiment of the present invention;

7 is a flowchart of another specific example of calculating the coordinates of the third virtual node in the embodiment of the present invention;

8 is a flowchart of a specific example of a virtual node-based multi-station cooperative interference location system provided in an embodiment of the present invention;

Fig. 9 is a flowchart of a specific example of a computer device provided in an embodiment of the present invention.

Detailed ways

The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

Example 1

An embodiment of the present invention provides a method for locating multi-station cooperative interference based on virtual nodes, which can be used to locate an interference source. As shown in Figure 1, the method includes the following steps:

Step S1: Acquire three nodes in the monitoring nodes as positioning nodes, which are a reference node, a second node and a third node respectively.

In the embodiment of the present invention, the signal source to be located is an interference source, and in the monitoring background, the strength of the received signal received by each monitoring node from the interference source, that is, the RSSI value of each monitoring node, is used to select the positioning node and the reference node. Therefore, the above-mentioned Step S1, as shown in Figure 2, specifically includes the following steps:

Step S11: obtain the first three nodes that receive the RSSI value of the signal source signal to be located in the monitoring node, and the first three nodes that are sorted by high and low are used as positioning nodes.

Step S12: respectively acquiring the RSSI value of the signal source signal to be located arriving at the positioning node.

Step S13: The positioning node with the largest RSSI value is used as the reference node, and the other two positioning nodes are respectively used as the second node and the third node.

After the positioning node and reference node are determined, the interference source is located according to the information of each positioning node obtained from the monitoring background. The information of each positioning node includes: the coordinates of each positioning node and the transmission time of the interference source signal reaching each positioning node. In the embodiment of the present invention, the monitoring background adopts the generalized cross-correlation method to calculate the transmission time between the interference source signal reaching different positioning nodes.

Step S2: Calculate the transmission time difference between the second node and the reference node to the signal source to be located, and the transmission time difference between the third node and the reference node to arrive at the signal source to be located.

In the embodiment of the present invention, the transmission time difference between the second node and the reference node reaching the signal source to be located is calculated according to the transmission time between the interference source signal reaching different positioning nodes, and the time difference between the third node and the reference node reaching the signal source to be located is calculated. transmission time difference.

Step S3: Determine the coordinates of the second virtual node according to the coordinates of the second node, the transmission time difference between the second node and the reference node reaching the signal source to be located and the direction in which the second node receives the signal.

In the embodiment of the present invention, the reference node is represented by N1, the second node is represented by N2, and the second virtual node is represented by N2'. Considering whether the receiving node is blocked or not, the transmission delay is affected, and four scenarios can be used to determine the first The coordinates of the two virtual nodes N2':

(1) When the reference node N1 is not blocked and the second node N2 is not blocked, as shown in Figure 3, the coordinates of the second virtual node N2' are calculated through the following steps:

Step S311: Calculate the difference between the transmission distances between the second node and the reference node according to the transmission time difference between the second node and the reference node when they arrive at the signal source to be located.

In the embodiment of the present invention, the difference value of the transmission distance between the second node and the reference node is calculated according to formula (1):

Among them, (x _i , y _i ) represents the coordinates of the ith node, (x, y) represents the coordinates of the interference source T, _{ri represents the distance between the interference source and the ith monitoring node, and r j represents} the interference source The distance from the jth monitoring node, d _ij represents the difference between the distances between the ith node and the jth node, and TDOA _ij is the transmission time difference between the ith node and the jth node reaching the signal source to be located ( For example, the generalized cross-correlation method in the prior art can be used to calculate the time difference between signals arriving at different monitoring nodes), n represents the number of monitoring nodes, and C represents the propagation speed of electromagnetic waves.

Therefore, the difference d ₁₂ of the transmission distance between the second node N2 and the reference node N1 can be calculated according to the above formula (1).

Step S312: Determine the coordinates of the second virtual node according to the coordinates of the second node, the difference in the transmission distance between the second node and the reference node, and the direction in which the second node receives the signal.

In the embodiment of the present invention, as shown in FIG. 4 , the second virtual node N2' is constructed so that the distance between the second node N2 and the second virtual node N2' is d ₁₂ , and the moving direction of the second node N2 is based on the received The signal direction of the interference source T is determined (if a signal from the left is received, the moving direction is determined to be moving to the left, and the same is true for the right), and the absolute coordinates of the second node N2 are used as the reference point. The difference d ₁₂ of the transmission distance between the nodes is moved by the same distance in the direction of the horizontal axis and the vertical axis respectively to determine the coordinates of the second virtual node N2 ′.

(2) When the reference node N1 is not blocked and the second node N2 is blocked, as shown in Figure 5, the coordinates of N2' are calculated through the following steps:

Step S321: According to the wireless propagation loss calculation formula, calculate the first transmission loss of the second node under the shielding environment and the second transmission loss under the unshielded environment, respectively.

In the embodiment of the present invention, under ideal conditions without shielding, the wireless propagation loss formula for calculating the second transmission loss is as follows:

P _loss =32.44+20lgd+20lgf (2),

Under the condition of occlusion, the wireless propagation loss formula for calculating the first transmission loss is as follows:

P _loss ⁽¹⁾ = 32.44+20lgd+20lgf+P _w (3),

Among them, P _loss represents the wireless transmission loss under the condition of no occlusion, P _loss ⁽¹⁾ represents the wireless transmission loss under the occlusion condition, d is the transmission distance, f is the interference frequency, and P _w represents the obstruction, multipath, etc. with occlusion loss due to conditions.

Step S322: Calculate the first distance that the second node reaches the signal source to be located according to the transmission time difference between the second node and the reference node reaching the signal source to be located.

In the embodiment of the present invention, the optimal radius of the reference node N1 is first calculated according to the SC (shrinking-circle) localization algorithm in the TDOA localization algorithm, and then according to the optimal radius of the reference node N1 and the arrival of the second node N2 and the reference node N1 to be determined The transit time difference of the bit signal source is calculated to obtain d ₂ .

Step S323: Determine the RSSI difference between the RSSI value of the second node and the RSSI value of the second virtual node according to the RSSI value of the second node, the first transmission loss, the first distance, and the distance between the reference node and the signal source to be located.

根据公式(3)可得出：In the embodiment of the present invention, the transmit power of the interference source is P _f , and the RSSI value received by the second node N2 is P ₂ .

According to formula (3), it can be obtained:

Among them, C is 32.44+20lgf, because the monitored interference frequency f is known, so C is a certain value. In the embodiment of the present invention, a difference calculation is performed after converting the transmission power P _f of the interference source into a unit of signal strength by using the conversion formula of power and signal strength in the prior art.

In order to make the geometric center of the triangle formed by the second virtual node N2' and the reference node N1 to be the position of the interference source, the distance between the second virtual node N2' and the interference source should be the same as the distance from the reference node N1 to the interference source. d ₁ is the same, suppose the value of RSSI received by the second virtual node N2' is P ₂ ⁽¹⁾ , then

P ₂ ⁽¹⁾ =P _f -20logd ₂ '-CP _w (5),

Wherein d ₂ ′ is the distance between the second virtual node N2 ′ and the interference source, which is the same as the distance d ₁ between the reference node N1 and the interference source.

Therefore, the RSSI difference P(Δ) between the second node N2 and the second virtual node N2' is:

P(Δ)=P ₂ -P ₂ ⁽¹⁾ =20lgd ₂ '-20lgd ₂ (6),

Step S324: Calculate the second distance between the second node and the signal source to be located in an unobstructed environment according to the power of the signal source to be located, the second transmission loss and the RSSI difference.

In the embodiment of the present invention, the received RSSI value of the second virtual node N2' under the condition of no blocking is P ₂ ⁽²⁾ , because the distance between the second virtual node N2' and the interference source and the distance between the reference node N1 and the interference source are The distances are equal, and they are all under ideal unobstructed conditions, so

P ₂ ⁽²⁾ =P _f -20lgd ₂ '-C=P ₁ (7),

Among them, P ₁ is the RSSI value received by the reference node N1, which can be directly obtained by monitoring the background.

Under ideal unobstructed conditions, the RSSI value received by the second node N2 is P ₂ ′, then

P ₂ '=P ₂ ⁽²⁾ +P(Δ) (8),

According to the above formula (4), the distance d ₂ ^* from the second node N2 to the interference source can be calculated in the ideal scenario, then

The above formula (9) and formula (7) can be used to calculate the distance d ₂ ^* from the second node N2 to the interference source.

Step S325: Determine the coordinates of the second virtual node according to the distance between the reference node and the signal source to be located, the second distance and the coordinates of the second node and the direction in which the second node receives the signal.

In the embodiment of the present invention, the straight-line distance that needs to be moved from the second node N2 to the second virtual node N2' is d ₂ ^* -d ₁ , and the absolute coordinates of the second node N2 are used as the reference point. The direction of the interference signal is determined (if the signal from the left is received, the moving direction is determined to move to the left, and the same is true for the right), and the second virtual node N2' is determined by moving the same distance in the horizontal and vertical directions respectively. coordinate of.

(3) When the reference node N1 is blocked and the second node N2 is not blocked, the receiving delay becomes longer because the reference node N1 is blocked, so that the estimated distance from the reference node N1 to the interference source is longer, and other Compared with the unobstructed node, the calculated delay difference is relatively small, and the moving distance is also shortened. However, considering that N1 is used as a reference node, the calculated optimal radius will provide a reference for the construction of other virtual nodes, so The radius of the constructed virtual node must be consistent with the reference node N1, and the second node N2 transmits in an unobstructed environment. Although the reference node N1 and the constructed second virtual node N2' are farther away from the interference source, the two Therefore, the method for determining the coordinates of the second virtual node N2' is the same as the method for scene (1), and will not be repeated here.

(4) When the reference node N1 is blocked and the second node N2 is blocked, each positioning node is affected by the same, and the relative delay difference is also accurate. Therefore, the second virtual node N2 is calculated according to the method of scenario (1). ' coordinates, which will not be repeated here.

S4: Determine the coordinates of the third virtual node according to the coordinates of the third node, the transmission time difference between the third node and the reference node reaching the signal source to be located, and the direction in which the third node receives the signal.

In the embodiment of the present invention, the reference node is represented by N1, the third node is represented by N3, and the third virtual node is represented by N3'. The principle of the coordinates is the same, and there are 4 scenarios to determine the coordinates of the third virtual node with N3':

Scenario (1) When the reference node N1 is not blocked and the third node N3 is not blocked, (3) When the reference node N1 is blocked and the third node N3 is not blocked, (4) When the reference node N1 is blocked and the third node is blocked When N3 is blocked, as shown in Figure 6, it includes the following steps:

Step S411: Calculate the difference in the transmission distance between the third node and the reference node according to the transmission time difference between the third node and the reference node reaching the signal source to be located;

Step S412: Determine the coordinates of the third virtual node according to the coordinates of the third node, the difference in the transmission distance between the third node and the reference node, and the direction in which the third node receives the signal.

The principle of determining the coordinates of the second virtual node N2' is the same as the above-mentioned scenarios (1), (3) and (4), and will not be repeated here.

Scenario (two) when the reference node N1 is not blocked and the third node N3 is blocked, as shown in Figure 7, the coordinates of the third virtual node N3 ' are calculated by the following steps:

Step S421: According to the wireless propagation loss calculation formula, calculate the third transmission loss of the third node under the shielding environment and the fourth transmission loss under the unshielded environment, respectively.

Step S422: Calculate the third distance that the third node reaches the signal source to be located according to the transmission time difference between the third node and the reference node reaching the signal source to be located.

Step S323: Determine the RSSI difference between the RSSI value of the third node and the RSSI value of the third virtual node according to the RSSI value of the third node, the first transmission loss, the third distance and the distance between the reference node and the signal source to be located.

Step S324: Calculate the fourth distance between the third node and the signal source to be located under the unobstructed environment according to the power of the signal source to be located, the fourth transmission loss and the RSSI difference.

Step S325: Determine the coordinates of the third virtual node according to the distance between the reference node and the signal source to be located, the fourth distance and the coordinates of the third node and the direction in which the third node receives the signal.

In the above scenario (2), when the reference node N1 is not blocked and the third node N3 is blocked, the calculation and calculation of the coordinates of the third virtual node N3' is the same as the principle of determining the coordinates of the second virtual node N2' in the above-mentioned scenario (2). ,No longer.

Step S5: construct a positioning combination according to the reference node, one of the second node and the second virtual node, and one of the third node and the third virtual node.

In the embodiment of the present invention, four co-localization combinations are constructed by (N1, N2, N3), (N1, N2', N3), (N1, N2, N3'), and (N1, N2', N3').

Step S6: Calculate the initial positioning coordinates of the signal source to be positioned corresponding to each positioning combination.

In the embodiment of the present invention, the calculation is performed according to the SC (shrinking-circle) positioning algorithm in the prior art, respectively, to obtain four initial positioning coordinates L1, L2, L3, L4 corresponding to the above-mentioned four co-location combinations.

Step S7: according to the RSSI value that each positioning node receives the signal source signal to be positioned, calculate the weighting coefficient of each positioning combination corresponding to the initial positioning coordinates respectively.

In this embodiment of the present invention, since the second virtual node N2' and the third virtual node N3' are at the same distance from the interference source as the reference node N1, the RSSI values of the second virtual node N2' and the third virtual node N3' are the same as the reference node N1. The RSSI values of the nodes are equal.

In the embodiment of the present invention, the average value of the RSSI value of each node in the positioning combination is calculated by the following formula:

Among them, RSSI _i represents the average value of the RSSI values of each node in the ith positioning combination, RSSI _ij represents the RSSI value of the jth node in the ith positioning combination, and n represents the number of nodes in each positioning combination. In this embodiment of the present invention, each positioning combination includes three nodes, so n is 3.

The weighting factor corresponding to the positioning combination is calculated by the following formula:

Wherein, w _i represents the weighting coefficient of the ith positioning combination, RSSI _i represents the average value of the RSSI values of each node in the ith positioning combination, and N represents the number of positioning combinations. In this embodiment of the present invention, there are four positioning combinations, so N is 4.

Step S8: according to the initial positioning coordinates and the corresponding weighting coefficients, calculate the positioning coordinates of the signal source to be positioned.

In the embodiment of the present invention, the positioning coordinates of the signal source to be located are calculated by the following formula:

Wherein, _wi represents the weighting coefficient of the _ith positioning combination, L represents the positioning coordinates of the signal source signal to be located, and Li represents the initial positioning coordinates of the ith positioning combination.

In the virtual node-based multi-station cooperative interference positioning method provided by the embodiment of the present invention, the first three nodes in which the monitoring node receives the RSSI value of the signal source signal to be located in the order of high and low are used as the positioning node, and the positioning node with the largest RSSI value is used as a reference. node, determine the coordinates of the second/third virtual node according to the coordinates of the second/third node, the transmission time difference between the second/third node and the reference node reaching the signal source to be located, and the direction in which the second/third node receives the signal; The reference node, one of the second node and the second virtual node, and one of the third node and the third virtual node constructs a positioning combination, calculates the initial positioning coordinates of each combination, and calculates the initial positioning coordinates and the corresponding weighting coefficient according to the initial positioning coordinates. Positioning coordinates of the signal source to be positioned. By constructing virtual nodes, the combination of nodes for co-location is enriched, the positioning error caused by node distribution is reduced, and the positioning accuracy is improved by using the weighting method of positioning results based on different cooperative combinations of RSSI values.

Example 2

An embodiment of the present invention provides a virtual node-based multi-station cooperative interference positioning system. As shown in FIG. 8 , the virtual node-based multi-station cooperative interference positioning system includes:

The positioning node obtaining module 1 is used to obtain three nodes in the monitoring nodes as positioning nodes, which are a reference node, a second node and a third node respectively. This module specifically executes the methods of steps S11 to S13 in Embodiment 1, and details are not described herein again.

The transmission time difference acquisition module 2 is used to calculate the transmission time difference between the second node and the reference node to the signal source to be located, and the transmission time difference between the third node and the reference node to the signal source to be located. This module specifically executes the method of step S2 in Embodiment 1, which is not repeated here.

The second virtual node coordinate determination module 3 is configured to determine the coordinates of the second virtual node according to the coordinates of the second node, the transmission time difference between the second node and the reference node reaching the signal source to be located, and the direction in which the second node receives the signal . For this module, refer to steps S311-S312 and steps S321-S325 recorded in Embodiment 1, and details are not repeated here.

The third virtual node coordinate determination module 4 is configured to determine the coordinates of the third virtual node according to the coordinates of the third node, the transmission time difference between the third node and the reference node reaching the signal source to be located, and the direction in which the third node receives the signal . For this module, refer to steps S411 to S412 and steps S421 to S425 recorded in Embodiment 1, which will not be repeated here.

The positioning combination building module 5 is configured to construct a positioning combination according to the reference node, one of the second node and the second virtual node, and one of the third node and the third virtual node. For this module, refer to step S5 recorded in Embodiment 1, and details are not repeated here.

The initial positioning coordinate calculation module 6 is used to calculate the initial positioning coordinates of the signal source to be positioned corresponding to each positioning combination. For this module, refer to step S6 recorded in Embodiment 1, and details are not repeated here.

The weighting coefficient acquisition module 7 is used to calculate the weighting coefficient of each positioning combination corresponding to the initial positioning coordinates according to the RSSI value of the signal source signal to be positioned received by each positioning node; this module refers to the step S7 recorded in the embodiment 1, and will not be repeated here. Repeat.

The positioning coordinate calculation module 8 is configured to calculate the positioning coordinates of the signal source to be located according to the initial positioning coordinates and the corresponding weighting coefficients. For this module, refer to step S8 recorded in Embodiment 1, and details are not repeated here.

In the virtual node-based multi-station cooperative interference positioning system provided by the embodiment of the present invention, the first three nodes in which the RSSI values of the signal source signals to be located received by the monitoring nodes are sorted in order of high and low are used as the positioning nodes, and the positioning node with the largest RSSI value is used as a reference. node, determine the coordinates of the second/third virtual node according to the coordinates of the second/third node, the transmission time difference between the second/third node and the reference node reaching the signal source to be located, and the direction in which the second/third node receives the signal; The reference node, one of the second node and the second virtual node, and one of the third node and the third virtual node constructs a positioning combination, calculates the initial positioning coordinates of each combination, and calculates the initial positioning coordinates and the corresponding weighting coefficient according to the initial positioning coordinates. Positioning coordinates of the signal source to be positioned. By constructing virtual nodes, the combination of nodes for co-location is enriched, the positioning error caused by node distribution is reduced, and the positioning accuracy is improved by using the weighting method of positioning results based on different cooperative combinations of RSSI values.

Example 3

An embodiment of the present invention provides a computer device, as shown in FIG. 9 , including: at least one processor 401 , such as a CPU (Central Processing Unit, central processing unit), at least one communication interface 403 , memory 404 , and at least one communication bus 402 . Among them, the communication bus 402 is used to realize the connection communication between these components. Wherein, the communication interface 403 may include a display screen (Display) and a keyboard (Keyboard), and the optional communication interface 403 may also include a standard wired interface and a wireless interface. The memory 404 may be a high-speed RAM memory (Ramdom Access Memory, volatile random access memory), or may be a non-volatile memory (non-volatile memory), such as at least one disk memory. The memory 404 can optionally also be at least one storage device located remotely from the aforementioned processor 401. The processor 401 can execute the virtual node-based multi-station cooperative interference location method described in FIG. 1 , a set of program codes are stored in the memory 404 , and the processor 401 calls the program codes stored in the memory 404 for executing Embodiment 1 A virtual node-based multi-station cooperative interference localization method in .

The communication bus 402 may be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus or the like. The communication bus 402 can be divided into an address bus, a data bus, a control bus, and the like. For ease of presentation, only one thick line is shown in Figure 9, but it does not mean that there is only one bus or one type of bus.

The memory 404 may include volatile memory (English: volatile memory), such as random-access memory (English: random-access memory, abbreviation: RAM); the memory may also include non-volatile memory (English: non-volatile memory) memory), such as flash memory (English: flash memory), hard disk (English: harddisk drive, abbreviation: HDD) or solid-state drive (English: solid-state drive, abbreviation: SSD); the memory 404 may also include the above-mentioned types of memory The combination.

The processor 401 may be a central processing unit (English: central processing unit, abbreviation: CPU), a network processor (English: network processor, abbreviation: NP), or a combination of CPU and NP.

The processor 401 may further include a hardware chip. The above hardware chip may be an application-specific integrated circuit (English: application-specific integrated circuit, abbreviation: ASIC), a programmable logic device (English: programmable logic device, abbreviation: PLD) or a combination thereof. The above-mentioned PLD may be a complex programmable logic device (English: complex programmable logic device, abbreviation: CPLD), a field programmable gate array (English: field-programmable gate array, abbreviation: FPGA), a general array logic (English: generic arraylogic , abbreviation: GAL) or any combination thereof.

Optionally, memory 404 is also used to store program instructions. The processor 401 can invoke program instructions to implement the virtual node-based multi-station cooperative interference location method provided in Embodiment 1 of the present application.

Embodiments of the present invention further provide a computer-readable storage medium, where computer-executable instructions are stored on the computer-readable storage medium, and the computer-executable instructions can execute the virtual node-based multi-station cooperative interference positioning in any of the foregoing method embodiments method. Wherein, the storage medium may be a magnetic disk, an optical disk, a read-only memory (Read-Only Memory, ROM), a random access memory (Random Access Memory, RAM), a flash memory (FlashMemory), a hard disk (Hard Disk) Drive, abbreviation: HDD) or solid-state drive (Solid-State Drive, SSD), etc.; the storage medium may also include a combination of the above-mentioned types of memories.

As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention 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 invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each process and/or block in the flowchart and/or block diagrams, and combinations of processes and/or blocks in the flowchart and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to the processor of a general purpose computer, special purpose computer, embedded processor or other programmable data processing device to produce a machine such that the instructions executed by the processor of the computer or other programmable data processing device produce Means for implementing the functions specified in a flow or flow of a flowchart and/or a block or blocks of a 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 function in a particular manner, such that the instructions stored in the computer-readable memory result in an article of manufacture comprising instruction means, the instructions The apparatus implements the functions specified in the flow or flow of the flowcharts and/or the block or blocks of the block diagrams.

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

Obviously, the above-mentioned embodiments are only examples for clear description, rather than limiting the implementation manner. For those of ordinary skill in the art, on the basis of the above description, other different forms of changes or modifications can also be made. There is no need and cannot be exhaustive of all implementations here. And the obvious changes or changes derived from this are still within the protection scope of the present invention.

Claims (10)

1. a kind of multi-station cooperative interference positioning method based on virtual node, is characterized in that, comprises the steps: Acquire three nodes in the monitoring nodes as positioning nodes, namely the reference node, the second node and the third node, including: Acquiring the first three nodes in the monitoring node that receive the RSSI values of the signal source signals to be located in order of high and low as the positioning nodes; Respectively obtain the RSSI value of the signal source signal to be located to each of the positioning nodes; Using the positioning node with the largest RSSI value as the reference node; Using the other two positioning nodes as the second node and the third node respectively; Calculate the transmission time difference between the second node and the reference node when they arrive at the signal source to be located, and the transmission time difference between the third node and the reference node when they arrive at the signal source to be located; Determine the coordinates of the second virtual node according to the coordinates of the second node, the transmission time difference between the second node and the reference node reaching the signal source to be located, and the direction in which the second node receives the signal; Determine the coordinates of the third virtual node according to the coordinates of the third node, the transmission time difference between the third node and the reference node reaching the signal source to be located, and the direction in which the third node receives the signal; constructing a positioning combination according to the reference node, one of the second node and the second virtual node, and one of the third node and the third virtual node; Calculate the initial positioning coordinates of the to-be-located signal source corresponding to each of the positioning combinations; According to the RSSI value of the signal source signal to be located received by each positioning node, the weighting coefficient of each of the positioning combinations corresponding to the initial positioning coordinates is calculated respectively; According to the initial positioning coordinates and the corresponding weighting coefficients, the positioning coordinates of the to-be-located signal source are calculated. 2. The virtual node-based multi-station cooperative interference positioning method according to claim 1, wherein, according to the coordinates of the second node, the transmission of the second node and the reference node to the signal source to be located The time difference and the direction in which the second node receives the signal, and the step of calculating the coordinates of the second virtual node, including: Calculate the difference in transmission distance between the second node and the reference node according to the transmission time difference between the second node and the reference node reaching the signal source to be located; The coordinates of the second virtual node are determined according to the coordinates of the second node, the difference between the transmission distances between the second node and the reference node, and the direction in which the second node receives signals. 3 . The method for locating multi-station cooperative interference based on virtual nodes according to claim 1 , wherein the said second node and the reference node reach the signal source to be located according to the coordinates of the second node, the second node and the reference node. 4 . The step of determining the coordinates of the second virtual node specifically includes: According to the wireless propagation loss calculation formula, respectively calculate the first transmission loss of the second node in the occlusion environment and the second transmission loss in the unobstructed environment; Calculate the first distance from the second node to the signal source to be located according to the transmission time difference between the second node and the reference node reaching the signal source to be located; Determine the RSSI value of the second node and the second virtual node according to the RSSI value of the second node, the first transmission loss, the first distance, and the distance between the reference node and the signal source to be located The RSSI difference of the RSSI value; Calculate the second distance between the second node and the to-be-located signal source in an unobstructed environment according to the power of the to-be-located signal source, the second transmission loss and the RSSI difference; The coordinates of the second virtual node are determined according to the distance between the reference node and the signal source to be located, the second distance, the coordinates of the second node, and the direction in which the second node receives signals. 4. The method for locating multi-station cooperative interference based on virtual nodes according to claim 1, characterized in that, according to the coordinates of the third node, the third node and the reference node arrive at the transmission of the signal source to be located. The step of calculating the coordinates of the third virtual node according to the time difference of the direction in which the third node receives the signal, specifically includes: Calculate the difference in the transmission distance between the third node and the reference node according to the transmission time difference between the third node and the reference node when they reach the signal source to be located; The coordinates of the third virtual node are determined according to the coordinates of the third node, the difference between the transmission distances between the third node and the reference node, and the direction in which the third node receives signals. 5. The method for locating multi-station cooperative interference based on virtual nodes according to claim 1, characterized in that, according to the coordinates of the third node, the third node and the reference node arrive at the transmission of the signal source to be located. The time difference and the direction in which the third node receives the signal, and the step of calculating the coordinates of the third virtual node, specifically includes: According to the wireless propagation loss calculation formula, respectively calculate the third transmission loss of the third node in the occlusion environment and the fourth transmission loss in the unobstructed environment; Calculate the third distance from the third node to the signal source to be located according to the transmission time difference between the third node and the reference node reaching the signal source to be located; Determine the RSSI value of the third node and the third virtual node according to the RSSI value of the third node, the third transmission loss, the third distance, and the distance between the reference node and the signal source to be located The RSSI difference of the RSSI value; Calculate the fourth distance between the third node and the to-be-located signal source in an unobstructed environment according to the power of the to-be-located signal source, the fourth transmission loss and the RSSI difference; The coordinates of the third virtual node are determined according to the distance between the reference node and the signal source to be located, the fourth distance, the coordinates of the third node, and the direction in which the third node receives signals. 6. The virtual node-based multi-station cooperative interference positioning method according to any one of claims 1 to 5, wherein, according to the RSSI value of the signal source signal to be located received by each positioning node, the corresponding positioning combination is calculated respectively. The steps of initially positioning the weighting coefficient of the coordinates include: The average value of the RSSI values of each node in the positioning combination is calculated by the following formula:

Wherein, RSSI _i represents the average value of the RSSI values of each node in the ith positioning combination, RSSI _ij represents the RSSI value of the jth node in the ith positioning combination, and n represents the number of nodes in each combination; The weighting coefficient corresponding to the positioning combination is calculated by the following formula:

Wherein, w _i represents the weighting coefficient of the ith positioning combination, RSSI _i represents the average value of the RSSI values of each node in the ith positioning combination, and N represents the number of positioning combinations. 7. The virtual node-based multi-station cooperative interference positioning method according to claim 6, wherein, according to the initial positioning coordinates and the corresponding weighting coefficients, the calculation of the positioning coordinates of the to-be-located signal source is performed. Step, calculate the positioning coordinates of the signal source to be located by the following formula:

Wherein, _wi represents the weighting coefficient of the _ith positioning combination, L represents the positioning coordinates of the signal source signal to be located, and Li represents the initial positioning coordinates of the ith positioning combination. 8. A virtual node-based multi-station cooperative interference positioning system, characterized in that, comprising: The positioning node obtaining module is used to obtain three nodes in the monitoring nodes as positioning nodes, which are the reference node, the second node and the third node respectively, including: Acquiring the first three nodes in the monitoring node that receive the RSSI values of the signal source signals to be located in order of high and low as the positioning nodes; Respectively obtain the RSSI value of the signal source signal to be located to each of the positioning nodes; Using the positioning node with the largest RSSI value as the reference node; Using the other two positioning nodes as the second node and the third node respectively; a transmission time difference acquisition module, configured to calculate the transmission time difference between the second node and the reference node when they reach the signal source to be located, and the transmission time difference between the third node and the reference node when they arrive at the signal source to be located; The second virtual node coordinate determination module is configured to determine the second node according to the coordinates of the second node, the transmission time difference between the second node and the reference node reaching the signal source to be located, and the direction of the signal received by the second node. The coordinates of the two virtual nodes; The third virtual node coordinate determination module is configured to determine the third node according to the coordinates of the third node, the transmission time difference between the third node and the reference node reaching the signal source to be located, and the direction of the signal received by the third node. The coordinates of the three virtual nodes; a positioning combination building module, configured to construct a positioning combination according to the reference node, one of the second node and the second virtual node, and one of the third node and the third virtual node; an initial positioning coordinate calculation module for calculating the initial positioning coordinates of the signal source to be positioned corresponding to each of the positioning combinations; a weighting coefficient obtaining module, configured to calculate the weighting coefficients corresponding to the initial positioning coordinates of each of the positioning combinations according to the RSSI value of the signal source signal to be positioned received by each positioning node; The positioning coordinate calculation module is configured to calculate the positioning coordinates of the signal source to be located according to the initial positioning coordinates and the corresponding weighting coefficients. 9. A computer device, comprising: at least one processor, and a memory communicatively connected to the at least one processor, wherein the memory stores instructions executable by the at least one processor, The instructions are executed by the at least one processor, so that the at least one processor executes the method for locating multi-station cooperative interference based on a virtual node according to any one of the preceding claims 1-7. 10. A computer-readable storage medium, characterized in that the computer-readable storage medium stores computer instructions, the computer instructions are used to cause the computer to Multi-station cooperative interference localization method for virtual nodes.

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