KR20180029818A - Method, server, and system for indoor localization - Google Patents

Abstract

The present invention relates to an indoor localization method for generating a radio map by using Wi-Fi simultaneous localization and mapping (WiFiSLAM) without an indoor map. The method comprises the steps of: (a) receiving a sensing value from a sensor of a user terminal, and measuring an estimated position of the user terminal; (b) obtaining a Wi-Fi signal pattern at the estimated position; (c) comparing the Wi-Fi signal pattern with a prestored Wi-Fi signal pattern to determine whether a prestored Wi-Fi signal pattern satisfies a preset standard of similarity with the Wi-Fi signal pattern; and (d) correcting the estimated position based on a previous position having the prestored Wi-Fi signal pattern if the prestored Wi-Fi signal pattern is present.

Description

[0001] METHOD, SERVER, AND SYSTEM FOR INDOOR LOCALIZATION [0002]

More particularly, the present invention relates to an indoor location measurement method, a server, and a system for measuring an indoor location using a Wi-Fi signal pattern received by a user terminal moving in an indoor space.

Recently, indoor location tracking technology has been applied not only to private sector such as indoor navigation, location based advertisement service and social network service, but also to emergency rescue service and rescuer (eg, firefighter) , Police officers, etc.) in the public sector. This indoor location recognition tracking technology recognizes the user's indoor location and continuously tracks the location. With the arrival of the IOT era, devices with various sensors are connected to the Internet, and thus the IOT commercialization And technology related to the recognition of the indoor position of each device is a technology field in which explosive demand is expected.

Conventional indoor positioning techniques include wireless local area network (WLAN) / Wi-Fi based technology, MagneticSystems technology, Ultra-Wideband (UWB) based technology, Radio Frequency Identification ) Based technology. Particularly, in the conventional technology based on WLAN / Wi-Fi, an indoor map is separately prepared and then the indoor position is measured using the corresponding map. Specifically, a WiFi / BT fingerprint database (static fingerprint DB) was constructed using a static search method or a dynamic search method using a preliminarily prepared indoor map.

Specifically, the static search method is a method of stopping at a predetermined position and collecting data (RSS (Received Signal Strength) of WiFi / BT) and then moving to another position to collect data. The dynamic search method is a method of generating a moving path on a map of a space in which a fingerprint is to be created and dynamically collecting data while moving along a predetermined moving path. Since the data acquisition location and data must be collected at the same time in the dynamic search method, approximate positions are measured by PDR (Pedestrian Dead Reckoning) technology, and the approximate positions are corrected by mapping the approximate positions to the predetermined travel route. However, since the PDR technique is a technique for measuring the position by accumulating the speed, it is very accurate in a short period of time, but the position error tends to increase with time.

In such a conventional position measurement method, in order to generate a radio map in which a fingerprint database, i.e., a Wi-Fi signal pattern at each specific position, is stored, indoors for indoor space is indispensably required. However, There is no precise indoor map of the space, or even if it is rough. Therefore, there is a limitation in measuring the indoor position by applying the conventional technique.

Korean Patent No. 10-1161103 U.S. Patent No. 9,258,681

It is an object of the present invention to provide a method of indoor location measurement for generating a radio map using a WiFi SLAM (WiFi SLAM) without an indoor map.

It is an object of the present invention to provide a method and apparatus for estimating a current position of a user through a PDR technology using a sensor built in a user terminal and then estimating a current position of the user based on the similarity between the Wi- Thereby generating a radio map.

According to a first aspect of the present invention, there is provided a method for measuring an indoor position, the method comprising: (a) receiving a sensing value from a sensor of a user terminal and calculating an estimated position of the user terminal; (b) obtaining a WiFi signal pattern at the estimated position; (c) comparing the Wi-Fi signal pattern with a pre-stored Wi-Fi signal pattern to determine whether there is a pre-stored Wi-Fi signal pattern satisfying a pre-set similarity with the Wi-Fi signal pattern; And (d) if the pre-stored Wi-Fi signal pattern exists, correcting the estimated position based on a previous position having the pre-stored Wi-Fi signal pattern.

Preferably, the step (a) may include receiving sensing values from the acceleration sensor and the gyro sensor of the user terminal, and calculating the estimated position according to the PDR algorithm using the sensing value.

Advantageously, the step (a) may include forming a connection between the estimated position and a previously calculated estimated position to generate a movement trajectory.

Preferably, the step (b) comprises: associating the strengths of the Wi-Fi signals received from the respective Wi-Fi terminals with the strengths of the Wi-Fi signals received by the user terminals from the plurality of Wi- And acquiring the WiFi signal pattern.

Preferably, the step (b) includes storing the estimated position and the Wi-Fi signal pattern in association with each other, wherein the stored estimated position and the Wi-Fi signal pattern may constitute a radio map.

Advantageously, the step (d) may include determining the estimated position and the previous position as the same position, and associating the estimated position with the previous position.

The step (d) may include a step of correcting the movement trajectory so that the distance difference between the connected estimated position and the previous position is minimized.

Preferably, if the pre-stored Wi-Fi signal pattern does not exist in the step (d) or after the estimated position is corrected, steps (a) to (d) may be repeated a predetermined number of times or more.

According to a second aspect of the present invention, there is provided an indoor positioning server comprising: an estimated position calculation unit for receiving a sensing value from a sensor of a user terminal and calculating an estimated position of the user terminal; A signal pattern obtaining unit for obtaining a WiFi signal pattern at the estimated position; A similarity checking unit comparing the WiFi signal pattern with a previously stored WiFi signal pattern to determine whether there is a pre-stored WiFi signal pattern satisfying a predetermined standard of similarity with the WiFi signal pattern; And an estimated position correcting unit for correcting the estimated position based on a previous position having the pre-stored Wi-Fi signal pattern when there is the pre-stored Wi-Fi signal pattern.

The estimated position calculation unit may receive the sensing values from the acceleration sensor and the gyro sensor of the user terminal, and may calculate the estimated position according to the PDR algorithm using the sensing value.

Preferably, the estimated position calculation unit may form a connection between the estimated position and the previously calculated estimated position to generate a movement trajectory.

Preferably, the signal pattern acquisition unit associates the strengths of the Wi-Fi signals received from the respective Wi-Fi terminals with the strengths of the Wi-Fi signals received from the plurality of Wi-Fi terminals by the user terminal at the estimated positions, A Wi-Fi signal pattern can be obtained.

Preferably, the signal pattern obtaining unit stores the estimated position and the Wi-Fi signal pattern in association with each other, and the stored estimated position and the Wi-Fi signal pattern may constitute a radio map.

Preferably, the estimated position correction unit may determine the estimated position and the previous position as the same position, and may link the estimated position with the previous position.

Preferably, the estimated position correction unit may correct the movement trajectory so that the distance difference between the connected estimated position and the previous position is minimized.

According to a third aspect of the present invention, there is provided an indoor positioning system including: a plurality of Wi-Fi terminals disposed in a specific indoor space to generate a Wi-Fi signal; A user terminal for receiving Wi-Fi signals generated from the plurality of Wi-Fi terminals and acquiring a sensing value from the sensors provided therein; And a controller for calculating an estimated position of the user terminal based on the sensed value received from the user terminal, acquiring a Wi-Fi signal pattern based on the strength of the Wi-Fi signals received from the user terminal, And an indoor location server for correcting the estimated location according to whether there is a pre-stored Wi-Fi signal pattern satisfying the set criteria.

As described above, according to the present invention, it is possible to generate a radio map using the PDR technology and the Wi-Fi signal pattern without indoor map, and to measure the indoor position of the user by using the generated radio map. In addition, the error of the PDR technique can be corrected effectively.

1 is a block diagram of an indoor positioning system according to a preferred embodiment of the present invention.
2 is a block diagram of a user terminal and an indoor location server according to an embodiment of the present invention.
3 is a flowchart illustrating a method of measuring an indoor position according to an exemplary embodiment of the present invention.
4 is an exemplary diagram illustrating WiFi terminals and reference points disposed in an indoor space.
5 is a diagram for explaining the PDR technique.
Figs. 6 to 9 are diagrams for explaining a method of correcting an estimated position. Fig.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving them will be more apparent from the following detailed description taken in conjunction with the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification. "And / or" include each and every combination of one or more of the mentioned items.

Although the first, second, etc. are used to describe various elements, components and / or sections, it is needless to say that these elements, components and / or sections are not limited by these terms. These terms are only used to distinguish one element, element or section from another element, element or section. Therefore, it goes without saying that the first element, the first element or the first section mentioned below may be the second element, the second element or the second section within the technical spirit of the present invention.

Also, in each step, the identification code (e.g., a, b, c, etc.) is used for convenience of explanation, and the identification code does not describe the order of each step, Unless the order is described, it may happen differently from the stated order. That is, each step may occur in the same order as described, may be performed substantially concurrently, or may be performed in reverse order.

The terminology used herein is for the purpose of illustrating embodiments and is not intended to be limiting of the present invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. It is noted that the terms "comprises" and / or "comprising" used in the specification are intended to be inclusive in a manner similar to the components, steps, operations, and / Or additions.

Unless defined otherwise, all terms (including technical and scientific terms) used herein may be used in a sense commonly understood by one of ordinary skill in the art to which this invention belongs. Also, commonly used predefined terms are not ideally or excessively interpreted unless explicitly defined otherwise.

In the following description of the present invention, detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. The following terms are defined in consideration of the functions in the embodiments of the present invention, which may vary depending on the intention of the user, the intention or the custom of the operator. Therefore, the definition should be based on the contents throughout this specification.

1 is a block diagram of an indoor positioning system according to a preferred embodiment of the present invention.

Referring to FIG. 1, an indoor location system 100 includes a Wi-Fi terminal 110, a user terminal 120, and an indoor location server 130.

The Wi-Fi terminal 110 is a device for generating a Wi-Fi signal and may be disposed in an indoor space, and preferably, a plurality of Wi-Fi terminals 110 may be provided in an indoor space.

The user terminal 120 is a terminal carried by a user who moves in the indoor space, and is a device that receives a Wi-Fi signal from the Wi-Fi terminal 110 and includes sensors therein. Preferably, the user terminal 120 may receive a Wi-Fi signal having different signal strengths generated from the respective Wi-Fi terminals 110 disposed in the indoor space. The sensing values of the respective sensors can be obtained through sensors such as an acceleration sensor and a gyroscope sensor provided therein and can be provided to the indoor position measurement server 130. For example, the user terminal 120 may be a smart phone based on an operating system that can freely use and delete various application programs desired by a user. In addition, the user terminal 120 has not only all the mobile phones having the mobile office function or the voice communication function but also all the tablet PCs that can access the internet, It is preferable that the communication device is a communication device.

The indoor location server 130 is connected to the user terminal 120 via a network to perform an indoor location measurement method. The indoor location server 130 receives the sensing values obtained from the sensors of the user terminal 120 and the Wi-Fi signals received by the user terminal 120 from the user terminal 120, The position of the user terminal 120 in the indoor space can be measured. Specifically, the indoor location server 130 may calculate the estimated location of the user terminal 120 by applying the PDR technology based on the sensing values, and may generate the radio map by correcting the estimated location based on the Wi- And measures the indoor position of the user terminal 120 using the measured position.

2 is a block diagram of a user terminal and an indoor location server according to an embodiment of the present invention.

2, the user terminal 120 includes an acceleration sensor 121, a gyroscope sensor 122, and a Wi-Fi signal receiving unit 123. The indoor location server 130 includes a PDR module 131, A Wi-Fi signal processing module 132, and an estimated position correcting unit 133. [ The PDR module 131 includes a step detection unit 211, a direction measurement unit 212 and an estimated position calculation unit 213. The WiFi signal processing module 132 includes a signal pattern acquisition unit 221, And a degree-of-similarity checking unit 222.

Hereinafter, a method for measuring an indoor position according to an embodiment of the present invention, which is performed through the respective components of the user terminal 120 and the indoor location server 130, will be described with reference to FIG.

First, the indoor position measurement method of the present invention can be preferably performed in the environment shown in FIG. Referring to FIG. 4, a plurality of Wi-Fi terminals 110 are arranged in an indoor space. When a user moves the indoor space with the user terminal 120, The position of the terminal 120 is measured. That is, the user terminal 120 periodically receives the Wi-Fi signal, and the Wi-Fi signal pattern at each of the reference points 400 is stored according to the periodic Wi-Fi signal, have.

The estimated position calculation unit 213 of the PDR module 131 of the indoor location measurement server 130 receives the sensing value from the sensor of the user terminal 120 and calculates the estimated position of the user terminal 120 ). More specifically, the step detection unit 211 of the PDR module 131 receives the sensing value obtained from the acceleration sensor 121 of the user terminal 120, and performs a step as shown in FIG. 5 (a) And the direction measurement unit 212 of the PDR module 131 receives the sensing value obtained from the gyroscope sensor 122 of the user terminal 12 and outputs the sensed value as the direction And the estimated position calculating section 213 of the PDR module 131 calculates the estimated position of the red light shown in Fig. 5 (c) according to the step and direction obtained through the step detecting section 211 and the direction measuring section 212, As shown in the graph, the estimated position of the user terminal 120 is calculated. That is, in the PDR module 131, the estimated position of the user terminal 120 is calculated according to a PDR (Pedestrian Dead Reckoning) algorithm using the sensing values obtained from the user terminal 120.

However, since the PDR algorithm gradually accumulates and increases the distance error over time, the user terminal 120 moves as shown in the black dotted line graph in FIG. 5 (c) It can be seen that the position of the user terminal 120 is calculated as the red graph shown in FIG. 5 (c) because the distance error gradually increases.

The estimated position calculating unit 213 forms a connection between the calculated estimated position and the previously calculated estimated position to generate a movement trajectory of the user terminal 120 as shown in FIG. . That is, each calculated estimated position becomes a node, and consecutive nodes are connected to a link, so that a movement trajectory can be generated.

Preferably, the indoor location server 130 may calculate the estimated location through the PDR module 131, and then determine the correction method of the estimated location according to whether there is an indoor map. In one embodiment, if there is an indoor map, the indoor location server 130 may generate a radio map by correcting the estimated location using a dynamic search method, and in another embodiment, The indoor location server 130 can generate the radio map by correcting the estimated position through the indoor position measuring method according to the present invention described below. The method of correcting the estimated position using the dynamic search method and generating the radio map is not described in detail here.

The signal pattern obtaining section 221 obtains the WiFi signal pattern at the estimated position (step S320). The signal pattern obtaining unit 221 obtains the signal pattern from the WiFi signal receiving unit 123 of the user terminal 120. The WiFi signal receiving unit 123 of the user terminal 120 receives the WiFi signals from the plurality of WiFi terminals 110, And acquires a Wi-Fi signal pattern. That is, the signal pattern obtaining unit 221 can obtain the Wi-Fi signal pattern by associating the strengths of the Wi-Fi signals received from the respective Wi-Fi terminals 110 with the Wi-Fi terminal 110, as shown in Table 1 below . For example, referring to Table 1, the intensity of each Wi-Fi signal generated from the Wi-Fi terminals AP1 to AP4 at the estimated position 1 is -41, -48, -63, and -64.

AP1 AP2 AP3 AP4 One -41 -48 -63 -64

Preferably, the signal pattern obtaining unit 221 may store the estimated position and the WiFi signal pattern in association with each other, and the radio map may be configured based on the stored position.

The similarity determination unit 222 compares the WiFi signal pattern with a previously stored WiFi signal pattern to determine whether there is a previously stored WiFi signal pattern that matches the WiFi signal pattern (step S330). Preferably, the similarity determination unit 22 can find a previously stored WiFi signal pattern having the highest degree of similarity to the WiFi signal pattern at the current estimated position, and the two points at which the degree of similarity of the WiFi signal pattern satisfies predetermined criteria are the same Location. ≪ / RTI > That is, since the intensities of the Wi-Fi signals received from the respective Wi-Fi terminals 110 at the same position are similar to each other, the present invention determines whether two points are at the same point by using such characteristics.

The estimated position correcting unit 133 corrects the estimated position based on the previous position having the pre-stored Wi-Fi signal pattern when there is the pre-stored Wi-Fi signal pattern satisfying the predetermined standard with the Wi-Fi signal pattern at the estimated position (Step S340). Preferably, the estimated position correcting unit 133 determines the estimated position and the previous position as the same position, connects the estimated position to the previous position, and corrects the movement locus so that the distance difference between the estimated position and the previous position, can do.

6, the PDR module 131 calculates the estimated position based on the PDR algorithm to generate a moving locus, and the WiFi signal processing module 132 calculates the estimated position based on the PDR algorithm. For example, referring to FIG. 6, If the signal pattern obtaining section 221 and the similarity verifying section 222 of the terminal 2 confirm two points of similar Wi-Fi signal patterns based on the similarity degree of the Wi-Fi signal pattern, , It is possible to connect two points having similar Wi-Fi signal patterns. In FIG. 6 (b), two points connected by a red line correspond to two points having similar WiFi signal patterns. Then, the estimated position correcting unit 133 corrects the movement locus so that the distance difference is minimized for the two points where the WiFi signal pattern is similar and connected to each other. Thus, the locus shown in FIG. 6 (b) Can be corrected to the moving locus shown in (c) of FIG. The graph shown in red in FIG. 6 (c) is a result of correcting the estimated position using the WiFi signal pattern according to the present invention, and the graph shown in black in FIG. 6 (c) , And the estimated position is corrected using the dynamic search method. Through this, it can be seen that the radio map obtained according to the present invention using the Wi-Fi signal pattern without indoor map is also highly accurate.

In one embodiment, if there is no pre-stored Wi-Fi signal pattern that the similarity to the Wi-Fi signal pattern at the estimated location satisfies a preset criterion, or after the estimated location is corrected by performing step S340, It is possible to repeat the steps S310 to S340 repeatedly a predetermined number of times or more according to the movement, and to perform radio communication such as the radio shown in [Table 2] on the basis of the WiFi signal pattern obtained in each reference point 400 according to repetition of steps S310 to S340 A map can be constructed. Here, the radio map means storing the Wi-Fi signal pattern at each specific location in the indoor space. Using the radio map, the user terminal 120 can receive the Wi-Fi signal from the user terminal 120 based on the strength of the Wi- Can be measured.

AP1 AP2 AP3 AP4 ... One -41 -48 -63 -64 ... 2 -49 -46 -66 -65 ... 3 -47 -50 -63 -56 ... ... ... ... ... ... ...

For example, referring to Table 2, the strength of Wi-Fi signals received from each of the Wi-Fi terminals AP1 to AP4 at the user terminal 120 at location 1 is (Received Signal Strength Indicator: RSSI) -41, -48, -63, and -64, and in position 2, the strength of the Wi-Fi signal received from each of the Wi-Fi terminals AP1 to AP4 is -49, -46, -66, and -65.

7 to 9 are diagrams for explaining a method of correcting the estimated position.

Hereinafter, with reference to FIGS. 7 to 9, there will be described a method of correcting the estimated position performed through the estimated position correcting unit 133 when it is confirmed that there is a similar WiFi signal pattern through the similarity confirming unit 222 Will be described in more detail.

Referring to FIG. 7, (a) of FIG. 7 shows an estimated position calculated through the PDR module 131, even though the user returns to the same position (START POINT) 8A, the pair of light blue nodes is actually calculated when the user terminal 120 has moved to the same position. In this case, As the estimated positions, it can be seen that they are displaced according to the distance error of the PDR algorithm.

The signal pattern acquisition unit 221 of the Wi-Fi signal processing module 132 receives the Wi-Fi signal from the user terminal 120 and transmits the Wi-Fi signal at the estimated position of the user terminal 120, And the similarity checking unit 222 checks the similarity between the WiFi signal pattern at the estimated location and the WiFi signal pattern stored at the estimated location. More specifically, the similarity determination unit 222 calculates the similarity between the currently stored WiFi signal pattern RSSI and the currently received WiFi signal pattern with probability through the following Equation 1, The position can be regarded as the same position.

[Formula 1]

Where P (X), P (RSSI ), P (X | RSSI present), P (RSSI previous | X) is a probability that the probability, the signal pattern RSSI is received is in the user terminal is located X, respectively, and a signal RSSI _present The probability that the user terminal is at location X when it is received and the probability that RSSI _previous is received when the user terminal is at location X. [

When the user terminal 120 moves only in one direction, the degree of similarity determination unit 222 calculates the degree of similarity in consideration of the moving direction of the user terminal 120, If it does, you can modify the index order.

When it is confirmed through the similarity determination unit 222 that there is a pre-stored WiFi signal pattern having a similarity to the WiFi signal pattern at the estimated position, the estimated position correction unit 133 determines that the pre- A connection between two points having similar Wi-Fi signal patterns can be formed. Specifically, as shown in FIG. 8 (b), a connection between two points having similar Wi-Fi signal patterns can be formed.

8 (c), the estimated position correcting unit 133 can optimize the movement trajectory so that the positional difference between the two connected points is minimized, for example, by using the Gauss-Newton method (Gauss-Newton Method) can be used to find a locus that minimizes the position difference.

More specifically, the estimated position correcting unit 133 can optimize the movement trajectory using various mathematical algorithms. Preferably, the estimated position correcting unit 133 may repeatedly perform the algorithm until the distance difference between the two similar points of the WiFi signal pattern becomes smaller than a predetermined reference while varying the parameters of the algorithm little by little. 9 (a), 9 (b), 9 (c), and 9 (d) , It can be seen that the distance difference between the two similar points of the WiFi signal pattern is reduced according to the repetition, and the signals are corrected almost in unison.

That is, according to the present invention, the distance error appearing at the estimated position calculated according to the PDR algorithm is corrected through the WiFi signal pattern at the estimated position, and two points having a similar WiFi signal pattern are regarded as the same position, And is corrected so that the movement trajectory is optimized, that is, the distance difference between the two points is minimized.

Meanwhile, the indoor location measurement method according to an embodiment of the present invention can also be implemented as a computer-readable code on a computer-readable recording medium. A computer-readable recording medium includes all kinds of recording apparatuses in which data that can be read by a computer system is stored.

For example, the computer-readable recording medium includes a ROM, a RAM, a CD-ROM, a magnetic tape, a hard disk, a floppy disk, a removable storage device, a nonvolatile memory, , And optical data storage devices.

In addition, the computer readable recording medium may be distributed and executed in a computer system connected to a computer communication network, and may be stored and executed as a code readable in a distributed manner.

Although the present invention has been described with respect to a preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, And this also belongs to the present invention.

100: Indoor positioning system
110: Wi-Fi terminal 120: User terminal
130: Indoor location server 121: Acceleration sensor
122: gyroscope sensor 123: WiFi signal receiver
131: PDR module 132: WiFi signal processing module
133: Estimated position correcting unit 211:
212: direction measuring unit 213: estimated position calculating unit
221: Signal pattern acquisition unit 222:

Claims (16)

(a) receiving a sensing value from a sensor of a user terminal and calculating an estimated position of the user terminal;
(b) obtaining a WiFi signal pattern at the estimated position;
(c) comparing the Wi-Fi signal pattern with a pre-stored Wi-Fi signal pattern to determine whether there is a pre-stored Wi-Fi signal pattern satisfying a pre-set similarity with the Wi-Fi signal pattern; And
(d) if the pre-stored Wi-Fi signal pattern exists, correcting the estimated position based on a previous position having the pre-stored Wi-Fi signal pattern.
The method of claim 1, wherein step (a)
Receiving sensing values from an acceleration sensor and a gyro sensor of the user terminal, and calculating the estimated position according to a PDR algorithm using the sensed value.
The method of claim 1, wherein step (a)
And generating a movement locus by forming a connection between the estimated position and the previously calculated estimated position.
The method of claim 1, wherein the step (b)
Acquiring the Wi-Fi signal pattern by correlating the strengths of the Wi-Fi signals received from the respective Wi-Fi terminals with the strengths of the Wi-Fi signals received from the plurality of Wi-Fi terminals at the estimated position by the user terminal The indoor position measurement method comprising the steps of:
The method of claim 1, wherein the step (b)
And storing the estimated location and the Wi-Fi signal pattern in association with each other, wherein the stored estimated location and the Wi-Fi signal pattern constitute a radio map.
2. The method of claim 1, wherein step (d)
Determining the estimated position and the previous position as the same position, and connecting the estimated position to the previous position.
7. The method of claim 6, wherein step (d)
And correcting the movement locus so that the distance difference between the connected estimated position and the previous position is minimized.
The method according to claim 1,
Wherein the steps (a) to (d) are repeatedly performed a predetermined number of times or more when the pre-stored Wi-Fi signal pattern is not present or after the estimated position is corrected in step (d).
An estimated position calculation unit for receiving a sensing value from a sensor of the user terminal and calculating an estimated position of the user terminal;
A signal pattern obtaining unit for obtaining a WiFi signal pattern at the estimated position;
A similarity checking unit comparing the WiFi signal pattern with a previously stored WiFi signal pattern to determine whether there is a pre-stored WiFi signal pattern satisfying a predetermined standard of similarity with the WiFi signal pattern; And
And an estimated position correcting unit for correcting the estimated position based on a previous position having the pre-stored Wi-Fi signal pattern when the pre-stored Wi-Fi signal pattern exists.
10. The apparatus according to claim 9, wherein the estimated position calculating section
Receiving the sensing values from the acceleration sensor and the gyro sensor of the user terminal, and calculating the estimated position according to the PDR algorithm using the sensing value.
10. The apparatus according to claim 9, wherein the estimated position calculating section
And generates a movement locus by forming a connection between the estimated position and a previously calculated estimated position.
The apparatus of claim 9, wherein the signal pattern obtaining unit
And the WiFi signal pattern is acquired by associating the strengths of the Wi-Fi signals received from the respective Wi-Fi terminals with the strengths of the Wi-Fi signals received from the plurality of Wi-Fi terminals at the estimated position by the user terminal The indoor position measurement server.
The apparatus of claim 9, wherein the signal pattern obtaining unit
And stores the estimated location and the Wi-Fi signal pattern in association with each other, and the stored estimated location and Wi-Fi signal pattern constitute a radio map.
The apparatus of claim 9, wherein the estimated position correction unit
Determines the estimated position and the previous position as the same position, and connects the estimated position with the previous position.
15. The apparatus of claim 14, wherein the estimated position correction unit
And corrects the movement locus so that a distance difference between the connected estimated position and the previous position is minimized.
A plurality of Wi-Fi terminals disposed in a specific indoor space to generate a Wi-Fi signal;
A user terminal for receiving Wi-Fi signals generated from the plurality of Wi-Fi terminals and acquiring a sensing value from the sensors provided therein; And
Calculating an estimated position of the user terminal based on the sensing value received from the user terminal, acquiring a Wi-Fi signal pattern based on the strength of the Wi-Fi signals received from the user terminal, And an indoor position measurement server for correcting the estimated position according to whether or not there is a pre-stored Wi-Fi signal pattern satisfying a criterion.

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