KR20210026519A - Method for verifying reliability of positioning and apparatus therefor - Google Patents

Abstract

The present invention relates to a method for confirming the reliability of a positioning result measured based on access point information, and a device therefor. According to an embodiment of the present invention, the method for confirming the reliability of position information measured based on access point information, comprises the steps of: receiving a plurality of pieces of access point information from a user terminal, and analyzing the access point information to perform positioning for a position of the user terminal; selecting access points having any one of a maximum latitude value, a minimum latitude value, a maximum longitude value, and a minimum longitude value from a position of each of the access points; determining a first axis by analyzing the positions of the selected access points; determining a second axis on the basis of a distance between the first axis and each of the access points; forming a virtual rectangle on the basis of the first and second axes, and calculating a density of the access points within the virtual rectangle; and confirming long and short axes among the first and second axes, and calculating the reliability on a positioning result using a ratio of the short axis to the long axis and the density. Accordingly, the accuracy of a currently measured position is recognized by a user.

Description

A method for verifying reliability of positioning and an apparatus therefor

The present invention relates to a method for checking the reliability of a positioning result measured based on access point information and an apparatus therefor.

With the development of mobile communication technology, a location measurement technology for measuring the location of a mobile terminal in a communication network is being actively researched. Representatively, GPS (Global Positioning System) location measurement technology using satellites and location measurement technology using a base station can be cited.

The location measurement technology using a base station has the advantage of not having to install a GPS receiver in the mobile terminal, but compared to the GPS location measurement technology, the error of location measurement reaches several tens to several hundred meters, making it difficult to apply in precise location positioning.

GPS location measurement technology is a technology that measures the location by analyzing satellite signals.When a GPS receiver enters an indoor or building dense area, the GPS signal cannot be received or the distortion is severe, making it difficult to apply to the building dense area and indoors. There was this.

In order to overcome this, research on WiFi-based positioning, which consumes relatively low power and enables periodic signal confirmation in a terminal, is continuously being conducted. The following patent document discloses a wireless LAN-based indoor location estimation method.

The conventional WiFi Positioning System (WPS) stores location information for each access point in advance to make the access point information current, and then analyzes the location of the access point collected in the surroundings to measure the user's location.

However, in the result of positioning the location using the information of the access point, the accuracy varies depending on the current accuracy of the access point and the surrounding environment. However, the current positioning technology does not provide an objective criterion for determining the reliability of the positioning results using the information of the access point, and also does not provide users with the reliability of the positioning results using the access point information. Actually.

Korean Patent Publication 10-2014-0146879 (2014.12.29)

The present invention has been proposed in order to solve such a problem, and relates to a positioning reliability checking method and apparatus for providing a user by evaluating the reliability of a positioning result of a mobile terminal measured based on access point information.

Other objects and advantages of the present invention can be understood by the following description, and will be more clearly understood by examples of the present invention. In addition, it will be easily understood that the objects and advantages of the present invention can be realized by the means shown in the claims and combinations thereof.

In order to achieve the above object, a method of checking the reliability of location information measured based on information of an access point according to an aspect of the present invention includes receiving information about a plurality of access points from a user terminal, and receiving information about the plurality of access points. Analyzing and locating the location of the user terminal; Selecting access points having any one of a maximum latitude value, a minimum latitude value, a maximum longitude value, and a minimum longitude value among the locations of each access point; Determining a first axis by analyzing the positions of the selected access points; Determining a second axis based on the distance between the first axis and each access point; Forming a virtual rectangle based on the first axis and the second axis, and calculating a density of an access point within the virtual rectangle; And checking a major axis and a minor axis among the first axis and the second axis, and calculating a reliability for the positioning result by using the ratio of the minor axis to the major axis and the density.

The determining of the first axis may include: checking a distance between the selected access points, and identifying two access points forming the longest distance among them; Setting a line connecting the identified two access points as a temporary first axis; Performing verification of the temporary first axis; And if the verification is successful, determining the temporary first axis as the final first axis.

In the performing of the verification, a first point of the two ends of the temporary first axis is a center point of a circle, and the temporary first axis is a radius, and a second point is a center point of the circle. Forming a second circle in which the temporary first axis becomes a radius; And checking whether all access points are located in both the first circle and the second circle, and determining that the verification succeeds when all access points are located in both the first circle and the second circle. can do.

The performing of the verification may include, if there is an access point that does not include either of the first circle and the second circle, checks the location of one or more access points not included in the circle, and accesses the one or more access points. Checking the location of the access point furthest from the center point of the circle from among the locations of the points; Resetting a line connecting the location of the farthest access point and the center point of the circle to a temporary first axis; And verifying the reset temporary first axis.

The determining of the second axis includes checking a first distance of an access point farthest in one vertical direction of the first axis, and checking a second distance of an access point farthest in another vertical direction of the first axis. , The second axis may be determined to be perpendicular to the first axis with a length obtained by adding the first distance and the second distance.

The method includes the steps of: checking a trust level for a location of each access point, and assigning a location weight to each access point according to the trust level; Assigning an electric field strength weight to each access point based on the received signal strength of each access point; And calculating an individual score of the access point by multiplying the electric field strength weight and the location weight, and calculating a total score of the access point by summing the individual scores of each access point. In this case, the step of calculating the reliability may calculate the reliability by additionally using the sum of the scores.

The method may further include, after the step of calculating the reliability, transmitting the positioning result and the calculated reliability to the user terminal.

The method includes analyzing information on a plurality of access points received from the user terminal, determining whether information on access points that are not adjacent to other access points within a preset radius exceeding a threshold number, and if present, , It may further include removing the information of the access point from the plurality of access point information.

Embodiments of the present invention may be implemented using a computer program recorded on a recording medium as a computer program that executes the above-described operation or method through a computer system.

According to another aspect of the present invention for achieving the above object, an apparatus for checking reliability of location information measured based on information of an access point includes: a communication unit for receiving information about a plurality of access points from a user terminal; A location measuring unit that analyzes the information of the plurality of access points and locates the location of the user terminal; Among the locations of each access point, access points having any one of a maximum latitude value, a minimum latitude value, a maximum longitude value, and a minimum longitude value are selected, and the first axis is determined by analyzing the locations of the selected access points. After determining the second axis based on the distance between the first axis and each access point, the long axis and the short axis of the first axis and the second axis are identified, and a virtual rectangle is formed based on the first axis and the second axis. A distribution confirmation unit that determines the density of the access points in the square of the And a reliability calculation unit that calculates the reliability of the positioning result of the position measurement unit using the ratio of the minor axis to the major axis and the density.

The present invention has the advantage of analyzing the access point information, calculating and providing the reliability of the positioning result, so that the user perceives the accuracy of the currently measured location.

In addition, the present invention has an advantage of being able to objectify an index used when evaluating the positioning result of the access point by analyzing the distribution of the access point and using it as an input factor in the reliability calculation.

The following drawings attached to the present specification illustrate preferred embodiments of the present invention, and serve to further understand the technical idea of the present invention together with specific details for carrying out the invention, so the present invention is described in such drawings. It is limited to matters and should not be interpreted.
1 is a diagram showing the configuration of a position measurement system according to an embodiment of the present invention.
2 is a diagram illustrating a reliability checking server according to an embodiment of the present invention.
3 illustrates a location of an access point collected from a user terminal according to an embodiment of the present invention.
4A and 4B are diagrams illustrating that a long axis and a short axis are formed according to an embodiment of the present invention.
5 is a flowchart illustrating a method of checking the reliability of a positioning result measured based on access point information in a reliability checking server according to an embodiment of the present invention.

The above-described objects, features, and advantages will become more apparent through the following detailed description in connection with the accompanying drawings, whereby those of ordinary skill in the technical field to which the present invention pertains can easily implement the technical idea of the present invention. There will be. In addition, in describing the present invention, when it is determined that a detailed description of a known technology related to the present invention may unnecessarily obscure the subject matter of the present invention, a detailed description thereof will be omitted. Hereinafter, a preferred embodiment according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram showing the configuration of a position measurement system according to an embodiment of the present invention.

As shown in FIG. 1, a location measurement system according to an embodiment of the present invention includes a plurality of access points 100-N, a user terminal 300, and a reliability verification server 200.

The access point (100-N) is a node to which the user terminal 300 can wirelessly access, and transmits and receives a radio signal to and from the user terminal 300. The access point 100 -N may be connected to the network 400 and transmit data received from the user terminal 300 to the network 400. The access point 100-N is installed indoors or outdoors. The access point 100-N induces wireless access of the user terminal 300 by transmitting a radio signal including its own identification information. A plurality of such access points 100-N may be installed in a specific area. The access point 100-N may be called a repeater, a small base station, a pico base station, a femto base station, or the like.

The user terminal 300 is a mobile communication device capable of communicating with the access point 100 -N or capable of communicating with the network 400. In order to access the network 400 through the access point 100-N, the user terminal 300 collects information on the access point 100-N detected at the current location, and among these access points, the user Connect to the selected access point (100-N). In particular, the user terminal 300 transmits a plurality of access point information (hereinafter referred to as'AP information') collected at the current location to the reliability verification server 200, so that the location of the user terminal 300 is determined by the reliability verification server ( 200). The AP information includes identification information of the access point and the strength of the received signal of the access point. The user terminal 300 may receive a location measurement result (eg, coordinate information) and a reliability of the positioning result from the reliability verification server 200. The reliability can be expressed in numerical form, and the lower the number, the higher the reliability.

The reliability check server 200 is a device that measures the location of the user terminal 300 and checks the reliability of the positioning result, and analyzes a plurality of AP information from the user terminal 300 to determine the location of the user terminal 300. Measure, and also check (i.e., evaluate) the reliability of the positioning results.

2 is a diagram illustrating a reliability checking server according to an embodiment of the present invention.

As shown in FIG. 2, the reliability check server 200 according to an embodiment of the present invention includes a database 260, a communication unit 210, a filtering unit 220, a location measurement unit 230, and a distribution check unit ( 240) and a reliability calculation unit 250, and these components may be implemented as hardware or software, or a combination of hardware and software. The reliability check server 200 is a computer system including a database 260, a communication unit 210, a filtering unit 220, a location measurement unit 230, a distribution check unit 240, and a reliability calculation unit 250. Can be configured.

In addition, the reliability checking server 200 may include one or more processors and a memory, and the functions of the filtering unit 220, the location measuring unit 230, the distribution checking unit 240, and the reliability calculating unit 250 are It may be included in the memory in the form of a computer program executed by the processor.

The database 260 is a disk device or the like, as a storage means, and stores information on the current access point 100-N. Specifically, the database 260 stores the identification information of the access point (100-N), the location information of the access point (100-N), and the information that the location trust level of the access point (100-N) is classified for each access point. do. The location reliability level indicates the degree of reliability of the location of the access point 100-N, and the higher the reliability level is given as the location of the access point 100-N is accurate. For example, if the location of the access point (100-N) is accurately recorded, the access point (100-N) may be given a rating of '0', which is the highest trust level, and the location of the access point (100-N) If is not accurate and is predicted through speculative interpolation, the corresponding access point (100-N) is given a rating between '1' to '8', which is an intermediate trust level, or '9', which is the lowest level, depending on the degree of reliability. 'A grade can be given. In addition, different location weights are applied to the trust level for each location of the access point 100-N. For example, a weight of '1' is applied to the '0' level, which is the highest position confidence level, and the weight is subtracted by'-0.1' as the level of '1' decreases from the highest confidence level, and each weight is reduced by confidence level. Can be applied differentially.

In addition, the database 260 stores a radio wave fingerprint map including radio wave patterns for each area. That is, the database 260 stores identification information of a plurality of access points and a radio wave fingerprint map in which radio signal strengths of the corresponding access points are recorded. In addition, the database 260 stores coordinates for each area.

The communication unit 210 performs a function of communicating with each of the user terminal 300 and the access point 100-N through the network 400. In particular, the communication unit 210 may receive a plurality of AP information from the user terminal 300. In addition, the communication unit 210 may transmit the positioning result (ie, location coordinates) and the reliability of the positioning result to the user terminal 300.

The filtering unit 220 analyzes a plurality of AP information received from the communication unit 210 and filters abnormal AP information from among them. Specifically, the filtering unit 220 searches the database 260 for access point location information corresponding to each access point identification information included in the plurality of AP information, and the access point ( 100-N) can be identified, and AP information used for location positioning can be selected from among them. At this time, the filtering unit 220 determines the access point 100-N that exists alone without other access points located nearby among the access points 100-N whose location has been checked as an abnormal access point, and determines the access point 100-N as an abnormal access point. Can be removed. At this time, the filtering unit 220 determines whether or not there are access points that are not adjacent to other access points within a preset radius, for example, more than a threshold number (eg, 1), and if there is, the corresponding access point has abnormal access. It is determined that it is a point and can be removed from the plurality of AP information.

3 illustrates a location of an access point collected from a user terminal according to an embodiment of the present invention.

As shown in FIG. 3, the user terminal 300 may acquire information on a plurality of APs, whose locations are indicated by red dots and yellow dots. However, among them, the access points indicated by yellow dots do not exist in clusters, but exist alone outside the clustered access point area. The filtering unit 220 may remove information about an access point, which is located independently of the plurality of AP information, not located within a certain radius of the other access point 100-N, from the plurality of AP information. In FIG. 3, AP information related to the access point indicated in yellow is removed.

The location measurement unit 230 measures the location of the user terminal 300 based on the filtered AP information. The location measuring unit 230 measures the location of the user terminal 300 by analyzing the strength of an access point radio signal of the filtered plurality of AP information. As an embodiment, the location measurement unit 230 compares the coincidence rate of the radio signal strength for each access point and the radio wave pattern included in each area of the radio fingerprint map identified from the plurality of AP information for each area, and among them, the highest coincidence rate is By determining the high area as the area where the user terminal 300 is located, the location of the user terminal 300 can be positioned. In another embodiment, the location measurement unit 230 applies the wireless signal strength for each access point to the signal loss path model, calculates the distance between each access point and the user terminal, and then calculates the distance between each access point 100-N. The location of the user terminal 300 may be positioned using the distance and the distance between the user terminal.

The location measurement unit 230 may transmit location information (eg, coordinate information) as a result of positioning to the user terminal 300 using the communication unit 210. In this case, the location measurement unit 230 may additionally transmit the reliability of the location location calculated by the reliability calculation unit 250 to the user terminal 300.

The distribution check unit 240 analyzes the plurality of AP information filtered by the filtering unit 220, sets an area in which the access point is distributed, and based on the distributed area, the ratio of the long axis and the short axis and the density of the access point Check. Specifically, the distribution check unit 240 searches the database 260 for access point location information corresponding to the identification information of each access point included in the plurality of AP information, and checks the access point location information in the vicinity of the user terminal 300. After determining the location of the access point 100-N, comparing the location (ie, latitude and longitude) of each access point 100-N, among the neighboring access points 100-N, the minimum latitude and latitude Each of the plurality of access points 100-N having any one of a maximum value, a minimum hardness value, and a maximum hardness value is identified, and the locations and identification information of the access point points are recorded in the first axis candidate list. The location of the access point recorded in the first axis candidate list is used to set the first axis.

The distribution checker 240 compares the distance between each access point based on the location of each access point included in the first axis candidate list, identifies two access points that form the longest distance among them, and checks the two access points. The line connecting the position of the point is set as a temporary first axis. The distribution check unit 240 verifies the temporary first axis, and when the verification is successful, determines the temporary first axis as the final first axis. Specifically, the distribution check unit 240 sets a first point (that is, the location of the first access point) among the two ends of the temporary first axis (ie, the location of the two access points) as the center point of the circle, A first circle having the length of the temporary first axis as a radius is formed, and it is checked whether all the filtered access points are located within the first circle. In addition, the distribution check unit 240 sets the second point (that is, the position of the second access point) out of the two ends of the temporary first axis (ie, the positions of the two access points) as the center point of the circle, and Another second circle whose length of one axis becomes a radius is formed, and it is checked whether all the filtered access points are located within this second circle. When all the filtered access points are located inside the first circle and the second circle, the distribution check unit 240 determines the temporarily set first axis as the final first axis.

On the other hand, if all the filtered access points in the first circle or the second circle are not located, the distribution check unit 240 checks the positions of one or more access points not included in the circle, and the at least one access point Among the locations of, the location of the access point farthest from the center point of the circle is checked, and the location of the access point at the farthest distance and the center point of the circle are reset to a temporary first axis. When the temporary first axis is reset, the distribution check unit 240 sets one of the two end points of the temporary first axis as the center point of the circle, and selects a third circle having the length of the temporary first axis as a radius. And check whether all the filtered access points are located inside the third circle. In addition, the distribution check unit 240 forms another fourth circle having the length of the first axis as a radius, and the other point among the two ends of the temporary first axis becomes the center point of the circle. It checks whether all the filtered access points are located inside. When all the filtered access points are located in the third circle and the fourth circle, the distribution check unit 240 determines the reset temporary first axis as the final first axis. If all the filtered access points are not located inside the 3rd circle and the 4th circle, after creating a new circle by resetting the temporary 1st axis according to the above procedure, the position of the filtered access point is changed to a new circle. After repeating the process of checking whether or not it is included in, the final first axis is determined.

When the first axis is finally determined, the distribution check unit 240 checks the first distance of the access point farthest in the vertical direction above the first axis, and determines the first distance of the access point farthest in the vertical direction below the first axis. After confirming the 2nd distance, the sum of the first and second distances is set as the length of the second axis. The angle between the first axis and the second axis is 90 degrees.

In addition, the distribution checking unit 240 sets a relatively long axis as a long axis among the first axis and a second axis as a long axis, and sets the relatively short axis as a short axis.

4A and 4B are diagrams illustrating that a long axis and a short axis are formed according to an embodiment of the present invention.

The points of FIGS. 4A and 4B represent coordinates where the access point 100-N is located. The distribution check unit 240 compares the locations of the access points as shown in FIG. 4A, and among them, confirms that the access point having the maximum hardness value is the access point 41 having the reference numeral 41, and the access point having the minimum hardness value It is confirmed that is the access point 43 having reference numeral 43 and records it in the first axis candidate list. In addition, the distribution checker 240 confirms that the access point having the maximum latitude value is the access point 44 having the reference numeral 44, and the access point having the minimum latitude value is the access point 42 having the reference numeral 42. Check it and record it in the candidate list for axis 1. The distribution checker 240 compares the distance between each access point based on the location of each access point included in the first axis candidate list. A straight line represented by a dotted line in FIG. 4A represents the distance between each access point. The distribution checker 240 compares the distances between the access points and confirms that the two access points forming the longest distance are an access point having a reference numeral 41 and an access point having a reference numeral 43. In addition, the distribution check unit 240 sets a straight line 46a connecting the positions of the two access points 41 and 43 corresponding to the 41 and 43 as the temporary first axis 46a.

The distribution check unit 240 uses a point 41 corresponding to the first point among the two end points 41 and 43 of the temporary first axis 46a as the center point of the circle, and the temporary first axis 46a. A first circle 47a is formed as a radius, and on the contrary, 43 points corresponding to the second point are used as the center point of the circle, and a second circle 47b is formed using the temporary first axis 46a as a radius. .

The distribution check unit 240 checks whether all the filtered access points are located in each of the first circle 47a and the second circle 47b. If all the access points are located in each of the first circle 47a and the second circle 47b, the distribution checker 240 may determine the temporary first axis 46a as the final first axis.

In FIG. 4A, all access points are located inside the second circle 47b, but the access point 45 such as 45 is not included in the first circle 47a, and accordingly, the distribution check unit 240 is (47a) The line 46b connecting the location 45 of the access point not included in the inside and the center point 41 of the first circle 47a is reset to the temporary first axis 46b.

In addition, the distribution check unit 240 is a third circle having a center point, and the temporary first axis 46b as a radius among the two ends 41 and 45 of the reset temporary first axis 46b. (48a) is formed, and on the contrary, 45 points are the central points, and a fourth circle 48b having the temporary first axis 46b as a radius is formed. According to FIG. 4A, the distribution check unit 240 determines the currently set temporary first axis 46b as all the access points are located inside the third circle 48a and the fourth circle 48b. It is decided by the axis.

When the first axis 46b is finally determined, the distribution check unit 240 determines the distance of the access point 49a farthest in a vertical direction of the first axis 46b (eg, vertically upward or vertically to the left). After checking the first distance, confirming the second distance of the access point farthest in the other vertical direction of the first axis (i.e., vertically downward or vertical to the right), this distance is the sum of the first distance and the second distance. Is determined as the distance of the second axis 50, and in addition, the second axis 50 is determined so as to be perpendicular to the first axis 46b.

4B is a view in which the first axis 46b of FIG. 4A is rotated to match the first axis 46b with the x-axis. The distribution check unit 240 sets a relatively long axis as a long axis among the first axis 46b and the second axis 50 as a long axis, and sets the relatively short axis as a short axis. 4A and 4B, the long axis becomes the first axis 46a and the short axis becomes the second axis 50.

In addition, as shown in FIG. 4B, a virtual right-angled rectangle may be formed using the long axis 46a and the short axis 50. In FIG. 4B, a portion represented by a solid line represents an imaginary right-angled rectangle. That is, the distribution check unit 240 may form a virtual right-angled rectangle in which the long axis becomes the first side and the short axis becomes the second side, as shown in FIG. 4B.

The distribution check unit 240 checks the ratio of the short axis to the long axis, and also checks the density of the access point in the virtual right-angled rectangle. In this case, the distribution check unit may check the density by checking the density ratio at which the access point exists per unit area set in advance.

The reliability calculation unit 250 checks the identification information of the access point included in the plurality of AP information, checks the location confidence level of the access point corresponding to the identification information in the database 260, and determines the access point according to this confidence level. Each location weight is assigned. Also. The reliability calculation unit 250 checks the received signal strength included in the plurality of AP information, checks whether the received signal strength belongs among the preset electric field strength classes, and the electric field strength score for each access point. Is given. For example, when the received signal strength corresponds to a strong electric field, the reliability calculation unit 250 may assign '1' as an electric field strength weight to the access point, and when the received signal strength corresponds to a heavy electric field, the electric field '0.25' may be assigned to the access point as the strength weight, and '0.11' as the electric field strength weight may be assigned to the access point when the received signal strength corresponds to a weak electric field.

The reliability calculation unit 250 may calculate an individual score of each access point by multiplying the location weight and the electric field strength weight.

Table 1 below exemplifies the calculation of the individual score of the access point.

Referring to Table 1, the electric field strength field indicates where the electric field strength corresponds to one of a strong electric field, a medium electric field, and a weak electric field, and the location confidence level field is the confidence in the accuracy of the access point 100-N stored in the database 260. Indicate the grade. In addition, the electric field strength weight field indicates a weight assigned according to the electric field strength, and the location weight field indicates a weight assigned in correspondence with the location confidence level. In addition, the result of multiplying the electric field strength weight and the location weight is recorded in the individual access point score field (that is, the individual AP score field).

The reliability calculation unit 250 adds up all the individual scores of the access point, calculates the total of the access point scores, and calculates the total score of the access point, the ratio of the short axis to the long axis checked by the distribution check unit 240, and By using the density of the access point, the reliability of the location positioning result of the user terminal 300 is calculated.

In this case, the reliability calculation unit 250 may calculate the reliability using the following equation.

Here, F is the reliability of the positioning result, ω is the total score of the access point, ρ is the ratio of the short axis to the long axis, and γ is the density of the access point.

The F means that the smaller the size, the higher the reliability, and the larger the size, the lower the reliability. In other words, the greater the total score of the access point, the higher the ratio of the short axis to the long axis, and the greater the density of the access point, the smaller the reliability F and the higher the reliability of the positioning result. On the other hand, the smaller the total score of the access point, the lower the ratio of the short axis to the long axis, and the smaller the density of the access point, the greater the reliability F, and thus the reliability of the positioning result decreases.

5 is a flowchart illustrating a method of checking the reliability of a positioning result measured based on access point information in a reliability checking server according to an embodiment of the present invention.

Referring to FIG. 5, the user terminal 300 collects information about a plurality of APs received around a current location and transmits it to the reliability checking server 200. The AP information includes radio signal strength and identification information of the access point.

Then, the communication unit 210 of the reliability checking server 200 receives a plurality of AP information from the user terminal 300 (S501). Next, the filtering unit 220 checks each access point identification information from the plurality of AP information, searches the database 260 for access point location information corresponding to the identification information of each access point, and searches the user terminal ( The location of each access point (100-N) checked in the vicinity of 300) is checked (S503). Subsequently, the filtering unit 220 determines whether or not there is an access point that is not adjacent to another access point by more than a threshold number (eg, 1) within a preset radius based on the location of each of the access points 100-N. If it is present, the AP information is filtered by determining that the corresponding access point is an abnormal access point and removing it from the plurality of AP information (S505).

The location measurement unit 230 analyzes the filtered information of a plurality of APs to measure the location of the user terminal 300 (S507). As an embodiment, the location measurement unit 230 compares the matching rate of the radio signal strength for each access point checked from the plurality of AP information and the radio wave pattern included in each area of the radio fingerprint map of the database 260 for each area. , Among them, an area having the highest matching rate may be determined as an area in which the user terminal 300 is located, and the location of the user terminal 300 may be positioned. As another embodiment, the location measurement unit 230 applies the wireless signal strength for each access point to the signal loss path model, calculates the distance between each access point and the user terminal, and then calculates the distance between each access point and the user terminal. The location of the user terminal 300 may be positioned using the distance.

The distribution checker 240 checks the minimum latitude value, the maximum latitude value, the minimum longitude value, and the maximum longitude value among the filtered locations of the access point (S509). At this time, the distribution check unit 240 may check the minimum latitude value, the maximum latitude value, the minimum longitude value, and the maximum longitude value using the location of each access point 100-N checked by the filtering unit 220. Alternatively, the distribution checker 240 checks the identification information of each access point from the AP information filtered by itself, searches the database 260 for the location information of the access point corresponding to the identification information of the access point, and is filtered. You can also check the location of each access point.

Next, the distribution check unit 240 stores the location and identification information of the plurality of access points 100-N having any one of a minimum latitude value, a maximum latitude value, a minimum longitude value, and a maximum longitude value in the first axis candidate list. Record it. Subsequently, the distribution checker 240 compares the distance between each access point based on the location of each access point included in the first axis candidate list, and identifies the two access points forming the longest distance among them, and the A line connecting the positions of the two access points is set as a temporary first axis. The distribution check unit 240 is a first point (that is, the position of the first access point) of the two ends of the temporary first axis (ie, the position of the two access points) is the center point of the circle, and the temporary first A first circle having an axis as a radius is formed, and a second point (position of the second access point) is a center point of the circle, and a second circle having the temporary first axis as a radius is formed.

The distribution checker 240 checks whether all the filtered access points are included in each of the first circle and the second circle, and if so, determines the temporary first axis as the final first axis.

On the other hand, if all the filtered access points in the first circle or the second circle are not located, the distribution check unit 240 checks the positions of one or more access points not included in the circle, and checks the positions of the checked one or more access points. Among the locations of the access points, check the location of the access point farthest from the center point of the circle. In addition, the distribution checker 240 resets a line connecting the center point of the circle and the location of the access point located at the farthest distance to a temporary first axis. When the temporary first axis is reset, the distribution check unit 240 sets one of the two ends of the temporary first axis (ie, the positions of the two access points) as the center point of the circle, and the temporary first axis A third circle with the axis distance as a radius is formed, and it is checked whether all filtered access points are located inside the third circle. In addition, the distribution check unit 240 forms another fourth circle with the distance of the first axis as a radius, and the other point among the two ends of the first axis temporarily becomes the center point of the circle. It checks whether all the filtered access points are located inside. When all the filtered access points are located in the third circle and the fourth circle, the distribution check unit 240 determines the reset temporary first axis as the final first axis. If all the filtered access points are not located inside the 3rd and 4th circles, after temporarily resetting the 1st axis according to the above-described procedure, after creating two new circles, the location of the filtered access point After repeating the process of checking whether is included in the two new circles, the final first axis is determined.

When the first axis is finally determined, the distribution check unit 240 sets a second axis perpendicular to the first axis. At this time, the distribution check unit 240 checks the first distance of the access point that is farthest away in one vertical direction of the first axis (eg, vertical direction to the left or vertical direction), and the other vertical direction of the first axis (eg, downward direction). After checking the second distance of the access point farthest in the vertical direction or the right vertical direction), the sum of the first distance and the second distance is set as the length of the second axis. In addition, the distribution checking unit 240 sets a relatively long axis as a long axis among the first axis and a second axis as a long axis, and sets the relatively short axis as a short axis.

Next, the distribution check unit 240 forms a virtual right-angled rectangle in which the long axis becomes the first side and the short axis becomes the second side (S511). And the distribution check unit 240 checks the ratio of the short axis to the long axis (S513). Subsequently, the distribution check unit 240 checks the density of the access point within the virtual right-angled rectangle (S515). In this case, the distribution check unit may check the density by checking the density ratio at which the access point exists per unit area set in advance.

Next, the reliability calculation unit 250 checks the identification information of the access point included in the filtered plurality of AP information, and checks the location reliability level of the access point corresponding to the identification information in the database 260. In addition, the reliability calculation unit 250 assigns a location weight for each access point according to the checked trust level for each access point (S517). Subsequently, the reliability calculation unit 250 checks the received signal strength included in the plurality of AP information, checks whether the received signal strength belongs among the preset electric field strength classes, and determines the electric field for each access point. An intensity score is given (S519). Next, the reliability calculation unit 250 calculates an individual score of each access point by multiplying the location weight and the electric field strength weight based on the same access point (S521). In addition, the reliability calculation unit 250 adds up all the individual scores of the access points, and calculates the sum of the scores of the access points (S523).

Then, the reliability calculation unit 250 substitutes the calculated total score of the access point, the ratio of the short axis to the long axis, and the density of the access point checked by the distribution check unit 240 into Equation 1, and the user terminal 300 ) Calculates the reliability of the position positioning result (S525).

When the calculation of the positioning result by the reliability calculation unit 250 is completed, the location measurement unit 230 uses the communication unit 210 to determine the location information of the user terminal 300 and the reliability of the user terminal 300. Can be transferred to.

As described above, the reliability checking server 200 according to an embodiment of the present invention analyzes AP information, calculates and provides a reliability for a positioning result, so that a user can recognize the reliability for a currently measured location.

While this specification includes many features, such features should not be construed as limiting the scope or claims of the invention. In addition, features described in separate embodiments herein may be combined and implemented in a single embodiment. Conversely, various features described in a single embodiment in the present specification may be individually implemented in various embodiments, or may be properly combined and implemented.

Although the operations have been described in a specific order in the drawings, it should not be understood that such operations are performed in a specific order as shown, or as a series of consecutive sequences, or that all described operations are performed to obtain a desired result. . Multitasking and parallel processing can be advantageous in certain environments. In addition, it should be understood that classification of various system components in the above-described embodiments does not require such classification in all embodiments. The above-described program components and systems may generally be implemented as a package in a single software product or multiple software products.

The method of the present invention as described above may be implemented as a program and stored in a recording medium (CD-ROM, RAM, ROM, floppy disk, hard disk, magneto-optical disk, etc.) in a form that can be read by a computer. This process can be easily performed by a person of ordinary skill in the art to which the present invention pertains, and thus will not be described in detail.

The present invention described above, for those of ordinary skill in the art to which the present invention pertains, various substitutions, modifications and changes are possible within the scope of the technical spirit of the present invention. It is not limited by the drawings.

100-N: Access point 200: Reliability verification server
210: communication unit 220: filtering unit
230: position measurement unit 240: distribution check unit
250: reliability calculation unit 260: database
300: user terminal 400: network

Claims (17)

As a method to check the reliability of the measured location information based on the information of the access point,
Receiving a plurality of access point information from a user terminal, analyzing the plurality of access point information, and locating the location of the user terminal;
Selecting access points having any one of a maximum latitude value, a minimum latitude value, a maximum longitude value, and a minimum longitude value from the locations of each access point;
Determining a first axis by analyzing the positions of the selected access points;
Determining a second axis based on the distance between the first axis and each access point;
Forming a virtual rectangle based on the first axis and the second axis, and calculating a density of an access point within the virtual rectangle; And
Checking the major axis and the minor axis among the first axis and the second axis, and calculating the reliability of the positioning result by using the ratio of the minor axis to the major axis and the density. . The method of claim 1,
The step of determining the first axis,
Checking the distance between the selected access points, and identifying two access points forming the longest distance among them;
Setting a line connecting the identified two access points as a temporary first axis;
Performing verification of the temporary first axis; And
Determining the temporary first axis as a final first axis if the verification is successful. The method of claim 2,
The step of performing the verification,
Of the two ends of the temporary first axis, a first point is a center point of a circle, and the temporary first axis forms a first circle having a radius, and a second point becomes the center point of the circle, and the temporary first axis is Forming a second circle that becomes a radius; And
Checking whether all access points are located in both the first circle and the second circle, and determining that the verification is successful when all the access points are located in both the first circle and the second circle; and How to check the reliability of positioning. The method of claim 3,
The step of performing the verification,
If there is an access point that does not include either the first circle or the second circle, the location of one or more access points not included in the circle is checked, and among the locations of the one or more access points, the original Checking the location of the access point farthest from the center point;
Resetting a line connecting the location of the farthest access point and the center point of the circle to a temporary first axis; And
And verifying the reset temporary first axis. The method of claim 1,
The step of determining the second axis,
After confirming the first distance of the access point furthest away in one vertical direction of the first axis and the second distance of the access point furthest away in the other vertical direction of the first axis, the first distance and the second distance And setting the second axis to be perpendicular to the first axis with a length obtained by summing the distances. The method of claim 1,
Checking a trust level for the location of each access point, and assigning a location weight to each access point according to the trust level;
Assigning an electric field strength weight to each access point based on the received signal strength of each access point; And
Calculating an individual score of the access point by multiplying the electric field strength weight and the location weight, and calculating the total score of the access point by summing the individual scores of each access point; and
The step of calculating the reliability,
Positioning reliability checking method, characterized in that calculating the reliability by additionally using the sum of the scores. The method of claim 6,
The step of calculating the reliability,
Positioning reliability checking method, characterized in that calculating the reliability by using the following equation.

Here, F is the reliability of the positioning result, ω is the total score of the access point, ρ is the ratio of the short axis to the long axis, and γ is the density of the access point. The method of claim 1,
After the step of calculating the reliability,
Transmitting the positioning result and the calculated reliability to the user terminal; The method of claim 1,
By analyzing information about a plurality of access points received from the user terminal, it is determined whether or not information on access points that are not adjacent to other access points within a preset radius exceeds a threshold number, and if there is, the corresponding access point Removing information from the plurality of access point information; positioning reliability checking method further comprising. A computer program that executes the method according to any one of claims 1 to 9 through a computer system, and is stored in a computer-readable recording medium. In the device for checking the reliability of the location information measured based on the information of the access point,
A communication unit for receiving information about a plurality of access points from a user terminal;
A location measuring unit that analyzes the information of the plurality of access points and locates the location of the user terminal;
Among the locations of each access point, access points having any one of a maximum latitude value, a minimum latitude value, a maximum longitude value, and a minimum longitude value are selected, and the first axis is determined by analyzing the locations of the selected access points. After determining the second axis based on the distance between the first axis and each access point, the long axis and the short axis are identified among the first axis and the second axis, and a virtual rectangle is formed based on the first axis and the second axis. A distribution confirmation unit that determines the density of the access points in the square of the And
Reliability checking apparatus comprising; a reliability calculation unit for calculating the reliability of the positioning result of the position measuring unit using the ratio of the short axis to the long axis and the density. The method of claim 11,
The distribution check unit,
Check the distance between the selected access points, set the line connecting the two access points forming the longest distance among them as a temporary first axis, and if the verification is successful by performing the temporary verification of the first axis The reliability checking device, characterized in that the temporary first axis is determined as the final first axis. The method of claim 12,
The distribution check unit,
Of the two ends of the temporary first axis, a first point is a center point of a circle, and the temporary first axis is a radius, a first circle is formed, and a second point becomes the center point of the circle, and the temporary first axis is Form a second circle that is a radius, and check whether all access points are located in both the first circle and the second circle, and verify if all access points are located in both the first circle and the second circle. Reliability checking device, characterized in that it is determined to be successful. The method of claim 13,
The distribution check unit,
If there is an access point that does not include either the first circle or the second circle, the location of one or more access points not included in the circle is checked, and among the locations of the one or more access points, the original And a line connecting the location of the access point farthest from the center point and the center point of the circle is reset to a temporary first axis, and verification is performed on the reset temporary first axis. The method of claim 11,
The distribution check unit,
After confirming the first distance of the access point furthest away in one vertical direction of the first axis and the second distance of the access point furthest away in the other vertical direction of the first axis, the first distance and the second distance And determining the second axis so as to be perpendicular to the first axis and having a length obtained by summing the distances. The method of claim 11,
The reliability calculation unit,
After checking the trust level for the location of each access point, assigning a location weight to each access point according to this trust level, and assigning an electric field strength weight to each access point based on the received signal strength of each access point. To calculate the individual score of the access point by multiplying the electric field strength weight and the location weight, calculate the total score of the access point by summing the individual scores of each access point, and additionally use the total score to calculate the reliability. Reliability check device characterized by. The method of claim 11,
The communication unit,
And transmitting the positioning result of the location measurement unit and the reliability calculated by the reliability calculation unit to the user terminal.

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