JP2017067565A - Terminal device and positioning program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable positioning to be performed even when the environment of positioning has been changed.SOLUTION: The present invention includes: an acquisition part 110, which acquires a BSSID for specifying the RSSIs of beacon signals from a terminal device 100 and a transmitter; and a positioning part 140, which performs positioning on the basis of combinations of RSSIs of the beacon signals from a plurality of transmitters other than a specific transmitter that have been acquired by the acquisition part 110.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a terminal device and a positioning program.

  In recent years, it has been proposed to perform positioning using short-range wireless communication technology in indoors where reception of GPS (Global Positioning System) radio waves is difficult (see, for example, Patent Document 1).

JP 2012-88237 A

  As a positioning method using short-range wireless communication technology, a wireless signal (for example, a beacon signal) from a transmitter is received by a terminal device such as a smartphone, and the position of the terminal device is specified based on the reception level of the wireless signal. There is. When such a technique is used, if the transmitter is moved, lost, deteriorated, damaged, etc., the positioning environment may change due to, for example, fluctuations in the reception level of the radio signal, and the position of the terminal device may not be specified. .

  The present invention has been made in view of the above problems, and an object of the present invention is to enable positioning even when a change occurs in the positioning environment.

  A terminal device according to an aspect of the present invention is a terminal device that performs positioning in an area where a plurality of transmitters are arranged at predetermined positions, and for specifying a reception level of radio signals from a transmitter and a transmitter. Acquisition means for acquiring the transmitter information and positioning means for performing positioning based on a combination of reception levels of each radio signal from a plurality of transmitters excluding a specific transmitter acquired by the acquisition means, Prepare.

  In addition, a positioning program according to one embodiment of the present invention provides a computer provided in a terminal device that performs positioning in an area where a plurality of transmitters are arranged at predetermined positions, the reception level and transmission of a radio signal from the transmitter. Positioning is performed based on the combination of the reception level of each radio signal from a plurality of transmitters excluding the specific transmitter acquired by the acquiring unit for acquiring transmitter information for specifying the transmitter and the acquiring unit It functions as a positioning means.

  In the terminal device and the positioning program, positioning is performed based on a combination of reception levels of radio signals from a plurality of transmitters excluding a specific transmitter. The specific transmitter is, for example, a transmitter that is in a state of movement, loss, deterioration, breakage, or the like, and causes a change in the positioning environment. If positioning is performed based on the combination of reception levels of radio signals from multiple transmitters including such transmitters, accurate positioning may not be possible due to the influence of changes in the positioning environment. There is sex. In the terminal device and the positioning program, since positioning is performed without using the reception level of the radio signal from such a transmitter, the terminal device and the positioning program are not easily affected by changes in the positioning environment. Therefore, positioning can be performed even when a change occurs in the positioning environment.

  The positioning means includes a reception level of each radio signal from a plurality of transmitters excluding a specific transmitter among reception levels of the radio signal acquired by the acquisition means, position information for specifying a position in the region, and the position Positioning may be performed by collating with a database in which the reception level of each wireless signal in FIG. For example, positioning can be performed by referring to such a database.

  The positioning means may update the database with positioning result information in which position information for specifying a position where positioning has been performed is associated with a reception level of a radio signal from a specific transmitter at the position. As a result, the contents of the database can correspond to changes in the positioning environment. For example, by referring to the updated database, it is possible to perform positioning corresponding to changes in the positioning environment.

  The positioning means may update the database when the reliability of positioning is equal to or higher than a predetermined reliability. Thereby, since the reliability of the contents of the updated database can be increased, the positioning accuracy when positioning is performed with reference to the updated database can be increased.

  The positioning unit compares the reception level of each radio signal from a plurality of transmitters including a specific transmitter among the reception levels of the radio signal acquired by the acquisition unit with the updated database to perform positioning. You may go. Thereby, even if it is the positioning environment after a change, positioning using a specific transmitter is attained.

  According to the present invention, positioning can be performed even when the positioning environment changes.

It is a figure for demonstrating the outline | summary of the method of positioning by embodiment. It is a figure which shows the functional block of a terminal. It is a 1st figure which shows an example of abnormal individual DB. It is a 2nd figure which shows an example of abnormal individual DB. It is a figure which shows an example of fingerprint DB. It is a figure for demonstrating the relationship between each position and RSSI of a beacon signal. It is a figure which shows an example of the difference of RSSI of each beacon signal, and RSSI in an initial state. It is a figure which shows an example of the hardware constitutions of a terminal. It is a figure which shows an example of a structure of a positioning program. It is a 1st flowchart which shows an example of the process performed in a terminal. It is a 2nd flowchart which shows an example of the process performed in a terminal. It is a 3rd flowchart which shows an example of the process performed in a terminal.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant descriptions are omitted.

  The terminal device according to the embodiment performs positioning in a predetermined area. The terminal device may be realized as a mobile terminal device such as a smartphone. The predetermined region is a region including a predetermined building, and such a region may hereinafter be simply referred to as a building. The building may be an outdoor facility. In a building, a plurality of transmitters are arranged at predetermined positions, whereby a plurality of nodes and links between the nodes are set. A node is an abstracted position in a building. The link indicates a connection path of each node. With such a structure using nodes and links (node / link structure), each position in the building is abstractly shown. For example, the position of the terminal device in a building can be specified (positioning) based on the information on which node the terminal device is staying at. Moreover, the movement path | route of the terminal device in a building can also be specified based on the information on which link (path | route) the terminal device moved along.

  The transmitter transmits a short-range wireless signal. The short-range wireless signal is a beacon signal that can be received within a range of several meters to several tens of meters from the transmitter, for example. As the beacon signal, for example, a WiFi (registered trademark) signal and a BLE (Bluetooth (registered trademark) Low Energy) signal may be used.

  FIG. 1 is a diagram for explaining the relationship between a transmitter arranged in a building and a node / link structure. FIG. 1A schematically shows a state in which a call is placed in a building. FIG. 1B shows a node / link structure corresponding to FIG. The transmitter may be arranged outside the building.

  In the example shown in FIG. 1A, the building 1 is assumed to be a store such as a supermarket. However, the building 1 is not limited to this example. In the building 1, a shelf 2 facing the passage 3 is arranged. A plurality of transmitters T are arranged in the building 1. In addition, the code | symbol from which TA-TF differs is attached | subjected to the transmitter T so that each transmitter can be distinguished. The transmitter T may be disposed at a connection point of each passage 3. In this example, transmitters TA to TF are disposed at connection points of the respective passages 3.

  As described above, the transmitter T transmits a beacon signal. Therefore, at each position P in the building 1, RSSI (Received Signal Strength Indicator) indicating the reception level of the beacon signal from each transmitter T is measured in advance, and a node N that abstractly indicates the measurement location is set. In addition, in order to distinguish each position, the different code | symbol of P1-P7 is attached | subjected to the position P. FIG. Further, different symbols N1 to N7 are attached to the node N so that the nodes can be distinguished. Nodes N1 to N7 correspond to the positions P1 to P7, respectively.

  As shown in FIG. 1B, the link L is set between the nodes N1 to N7. The link L is a path that can transit between the nodes N1 to N7. The link L can correspond to, for example, only a route that can be moved by the user of the terminal device among all the routes connecting the nodes N1 to N7. In this case, the link L corresponds to the passage 3. The node / link structure shown in FIG. 1B may be represented by a directed graph. In this case, even if the link L is set between the same nodes N, the one node N to the other The property of the link L (for example, movement cost) may be different between the route toward the node N and the route from the other node N to the one node N.

  As described above, the floor map of the building 1 is abstracted as a node / link structure (graph structure). By using such a node / link structure, positioning in the building 1 can be performed. For example, if the RSSI of the beacon signal from each transmitter T is acquired at a certain position of the building 1 and the acquired RSSI is compared (matched) with the previously measured RSSI described above, the position is determined. , Which node in the node link structure is located is specified. Since the node / link structure is an abstraction of the floor map of the building 1, if the position in the node / link structure is specified, the position in the building 1 is also specified therefrom.

  Here, the state of the transmitter T when the RSSI of the beacon signal from each transmitter T is measured in advance at each position of the building is referred to as an “initial state”. In the initial state, the transmitter T is placed under a condition that, for example, the output level of the beacon signal transmitted from the transmitter T is a predetermined level, and the installation location of the transmitter T is a predetermined location. Means that

  FIG. 2 is a diagram illustrating functional blocks of the terminal device according to the embodiment. As illustrated in FIG. 2, the terminal device 100 includes an acquisition unit 110, a detection unit 120, a determination unit 130, a positioning unit 140, a control unit 150, a communication unit 160, and a storage unit 170.

  The acquisition unit 110 receives a beacon signal from the transmitter T, thereby acquiring RSSI (Received Signal Strength Indicator) of the beacon signal in the terminal device 100 and transmitter information for specifying the transmitter T ( Acquisition means). The transmitter information is, for example, a BSSID (Basic Service Set Identifier). The RSSI and transmitter information history acquired by the acquisition unit 110 can be stored in the storage unit 170 described later.

  In the example illustrated in FIG. 2, the acquisition unit 110 includes a WiFi signal reception unit 111 and a BLE signal reception unit 112. The WiFi signal receiving unit 111 is a part that receives a WiFi signal. When the beacon signal is a WiFi signal, the WiFi signal reception unit 111 receives the beacon signal. The BLE signal receiving unit 112 is a part that receives a BLE signal. When the beacon signal is a BLE signal, the BLE signal receiving unit 112 receives the beacon signal.

  The detection unit 120 is a part (detection means) that detects the transmitter T in an abnormal state. The transmitter T in the abnormal state is a transmitter T in a state different from the initial state. For example, the state in which the transmitter T has moved from the initial installation location to a different installation location, the state in which the transmitter T has been lost, etc. are abnormal states. In addition, the transmitter T is deteriorated, the output level of the beacon signal transmitted from the transmitter T is lower than the output level in the initial state, the transmitter T is damaged, etc., and the beacon signal is not transmitted. State. Note that the decrease in the output level of the beacon signal due to deterioration of the transmitter T is caused by, for example, a decrease in the battery voltage of the transmitter T. When the remaining amount of the battery becomes zero, the transmission of the beacon signal of the transmitter T is stopped.

  In the example shown in FIG. 2, the detection unit 120 includes an abnormal solid detection unit 121 and a movement destination detection unit 122. The abnormal solid detector 121 detects the transmitter T in an abnormal state. For example, when the RSSI of the beacon signal from the transmitter T acquired by the acquisition unit 110 is different from the RSSI of the beacon signal from the transmitter T in the initial state, the abnormal solid detection unit 121 transmits the beacon signal. The transmitter T to be detected is detected as the transmitter T in an abnormal state. In addition, it is determined by the determination part 130 mentioned later what kind of abnormal state the transmitter T detected by the abnormal solid detection part 121 is in an abnormal state. The movement destination detection unit 122 detects the movement destination of the transmitter T when the transmitter T in the abnormal state is moved from the installation location in the initial state. Further details of the detection method by the abnormal solid detection unit 121 and the movement destination detection unit 122 will be described later.

  The determination unit 130 is a part (determination unit) that determines the abnormal state of the transmitter T in the abnormal state detected by the detection unit 120. The determination of the abnormal state is to determine what abnormal state the transmitter T is in, including the above-mentioned movement, loss, deterioration, breakage, and the like. The determination unit 130 determines the abnormal state of the transmitter T based on the RSSI of the beacon signal acquired from the transmitter T and the history of transmitter information acquired by the acquisition unit 110 as the terminal device 100 moves in the building 1. . Details of the determination method by the determination unit 130 will be described later.

  The positioning unit 140 is a part (positioning means) that performs positioning of the terminal device 100. The positioning unit 140 is based on the RSSI combination of beacon signals from a plurality of transmitters T excluding a specific (in an abnormal state) transmitter T among the plurality of transmitters T acquired by the acquisition unit 110. Perform positioning. The specific transmitter T is a transmitter T in an abnormal state, and may be, for example, the transmitter T detected by the detection unit 120 as being in an abnormal state.

  In the example illustrated in FIG. 2, the positioning unit 140 includes a matching unit 141 and an update unit 142. The collation unit 141 collates RSSI from a plurality of transmitters T excluding the transmitter T in an abnormal state among the RSSIs acquired by the acquisition unit 110 and a fingerprint DB 173 stored in the storage unit 170 described later. By doing so, positioning of the terminal device 100 is performed. As will be described later, the fingerprint DB 173 describes position information (location ID) for specifying the position in the building 1 and the RSSI of the beacon signal from each transmitter T at the position. Details of the fingerprint DB 173 will be described later with reference to FIG. The update unit 142 updates the fingerprint DB 173. Further details of the verification method by the verification unit 141 and the update method by the update unit 142 will be described later.

  The control unit 150 is a part that performs overall control of the terminal device 100 by controlling each element included in the terminal device 100.

  The communication unit 160 is a part that communicates with the outside of the terminal device 100. For example, the communication unit 160 can additionally acquire or update various information stored in the storage unit 170 described later.

  The storage unit 170 is a part that stores various information necessary for processing executed by the terminal device 100. For example, the memory | storage part 170 matches and memorize | stores the beacon signal RSSI from the transmitter T of the initial state in each position in the building 1, and transmitter information. This will be described later with reference to FIG. In addition, the storage unit 170 stores the RSSI of the beacon signal and the history of transmitter information (history information) in the terminal device 100 acquired by the acquisition unit 110. The history information describes, for example, each position in the building 1, the RSSI, and the BSSID of the transmitter T in association with each other. The history information may include time information. Further, the storage unit 170 performs a program (detection program) for causing the terminal device 100 to execute processing necessary for detecting the transmitter T in which the terminal device 100 is in an abnormal state, and performs positioning of the terminal device 100. A program (positioning program) for causing the terminal device 100 to execute processing necessary for this is stored. Further, in the example illustrated in FIG. 2, the storage unit 170 stores an abnormal individual DB 171, a graph DB 172, and a fingerprint DB 173.

  The abnormal individual DB 171 stores information related to the transmitter T detected as the transmitter T in an abnormal state. FIG. 3 is a diagram illustrating an example of the abnormal individual DB 171. In the example shown in FIG. 3, the abnormal individual DB describes “BSSID”, “abnormal status”, and “destination” in association with each other.

  “BSSID” is an identifier for identifying the transmitter T, and is generally called a MAC address. In the example shown in FIG. 3, the BSSID is represented by a combination of a numerical value and an alphabet (such as “00: 00: 00: AA: BB: CC”).

  The “abnormal status” indicates the type of abnormal state of the transmitter T. In the example shown in FIG. 3, the abnormal status is represented by a character string (“stop”, “move”, “deteriorated”, etc.). The contents of the abnormal status are as described above.

  “Destination” indicates the installation location of the transmitter T after movement. In the example shown in FIG. 3, the movement destination is represented by a number (such as “13”). For example, a number (location ID) indicating each position in the node / link structure ((b) in FIG. 1) is defined, and “movement destination” indicates the location ID. Some place IDs may be identifiers indicating the node N. Note that the movement destination is set when the abnormal status is movement, and is not set otherwise (“NULL”).

  FIG. 4 is a diagram illustrating another example of the abnormal individual DB 171. Here, the abnormal individual DB 171 stores information on whether or not an abnormality has occurred in each transmitter T. In the example shown in FIG. 4, in the abnormal individual DB 171, either “True” or “False” flag is set for each of the transmitters TA to TB. “True” indicates that the transmitter T is in an abnormal state. “False” indicates not (for example, in an initial state).

  The fingerprint DB 173 stores a combination of each position in the building 1 and the RSSI of the beacon signal from each transmitter T at each position. FIG. 5 is a diagram illustrating an example of the fingerprint DB 173. In the example shown in FIG. 5, the fingerprint DB 173 corresponds to “location ID”, “RSSI_TA”, “RSSI_TB”, “RSSI_TC”, “RSSI_TD”, “RSSI_TE”, and “RSSI_TF”. Describe.

  The “location ID” is an identifier indicating the location of the node N shown in FIG. In the example shown in FIG. 5, the location ID is represented by a number (such as “1”). For example, the place ID “1” corresponds to the node N1 ((b) in FIG. 1).

  “RSSI_TA” to “RSSI_TF” indicate RSSIs of beacon signals from the transmitters TA to TF at each position of the building 1 indicated by the corresponding place ID. “RSSI_TA” to “RSSI_TF” may be the BSSID of the corresponding transmitter T. In the example shown in FIG. 5, each RSSI value is represented by a numerical value (such as “−62”). The unit of RSSI is, for example, dBm.

  The information stored in the fingerprint DB 173 has been measured in advance as described above with reference to FIG. However, as will be described later, the information stored in the fingerprint DB 173 can be updated by the update unit 142 of the positioning unit 140. In addition, the measurement may be performed a plurality of times at the same position. In the example shown in FIG. 5, from each transmitter T measured a plurality of times (for example, twice) for the same place ID (for example, “1”). Each RSSI of the beacon signal is stored.

  Next, an example of a technique for detecting the transmitter T in an abnormal state by the detection unit 120 will be described with reference to FIGS. 6 and 7.

  FIG. 6 shows an example of RSSI of a beacon signal from each transmitter T in an initial state at each position in a building. This measurement is performed using the function of the acquisition part 110 of the terminal device 100, for example. The horizontal axis of the graph in FIG. 6 indicates time, and the vertical axis indicates RSSI. Here, as illustrated on the lower side of the graph in FIG. 6, the terminal device 100 sequentially moves through the building 1 at a predetermined speed and receives the RSSI of the beacon signal from each transmitter T. Thus, the RSSI at each time may be measured. In this case, the horizontal axis of the graph indicates time and also indicates each position in the building. In addition, in FIG. 6, the example of four transmitters, transmitter TA-TD, is shown.

  RSSIs of beacon signals from the respective transmitters TA to TD are indicated by curves CA to CD, respectively. At the position corresponding to each transmitter T (the position closest to the transmitter T), the RSSI of the beacon signal from the transmitter T is maximized. Here, a threshold is set for each RSSI of each beacon signal. Each threshold value is set to a value smaller than the maximum value of the corresponding beacon signal RSSI.

  The information given by the graph shown in FIG. 6 including the threshold value, that is, the RSSI of the beacon signal transmitted from the transmitter T in the initial state at each position in the building and the RSSI of each beacon signal are set. Information in which the threshold value and the transmitter information are associated with each other is stored in the storage unit 170 in advance. By referring to the information stored in the storage unit 170, the abnormal solid detection unit 121 of the detection unit 120 detects the transmitter T in an abnormal state. Specifically, the abnormal solid detection unit 121 compares the RSSI of the beacon signal in the terminal device 100 when the beacon is transmitted from the transmitter T in the initial state with the RSSI acquired by the acquisition unit 110. In the example illustrated in FIG. 6, the RSSI indicated by the curves CA to CD and the RSSI acquired by the acquisition unit 110 are compared. For example, the RSSI acquired by the acquisition unit 110 is compared with the threshold value at a position where the RSSI indicated by each of the curves CA to CD is predicted to be larger than the corresponding threshold value. In that case, the comparison result is a result of whether or not the acquired RSSI is larger than the threshold value. Then, the abnormal solid detector 121 detects the transmitter T in an abnormal state based on the comparison result and the transmitter information acquired by the acquisition unit 110. For example, the transmitter T corresponding to the BSSID of the beacon signal whose RSSI acquired by the acquisition unit 110 is equal to or less than the threshold is detected as the transmitter T in an abnormal state. This is because the RSSI of the beacon signal from the transmitter T that is actually acquired is significantly changed (decreased) relative to the level of the beacon signal from the transmitter T in the initial state, and there is some abnormality in the transmitter T. This is because it is considered that this occurs.

  Alternatively, the transmitter T in an abnormal state may be detected as follows. That is, when the terminal device 100 moves in order through each position of the building 1, the terminal device 100 moves along each link N along each node N realized by each transmitter T. For example, in the example shown in FIG. 6, when the terminal device 100 moves in this order through the nodes N corresponding to the transmitters TA, TB, and TC, the beacon signals from the transmitter TA and the transmitter TC are normally received. (For example, RSSI is larger than the threshold) On the other hand, when transmitter TB is in an abnormal state, the beacon signal from transmitter TB is not normally received (for example, RSSI is below the threshold or the beacon signal itself is not observed). Is assumed. That is, it is assumed that a beacon signal from the transmitter TA and a beacon signal from the transmitter TC are acquired in this order. In this case, on the node / link structure, the terminal device 100 has moved the node N realized by the transmitter TA and the node N realized by the transmitter TC in this order. Here, for example, in order for the node link structure to move from the node N realized by the transmitter TA to the node N realized by the transmitter TC, the node link structure must pass through the node N realized by the transmitter TB. If the node / link structure is required, the transmitter TB may be detected as being in an abnormal state in response to the movement of the node N realized by the transmitter TB without passing through the terminal device 100. it can. As described above, the abnormal solid detection unit 121 detects the transmitter T in the abnormal state based on the RSSI and BSSID acquisition order of the beacon signal from the transmitter T acquired by the acquisition unit 110 as the terminal device 100 moves. May be detected.

  In the example of FIG. 6 described above, the detection of the transmitter T in the abnormal state is determined based only on the RSSI of the beacon signal from the transmitter T, but the detection of the transmitter T in the abnormal state is The determination may be made based on RSSI of beacon signals from a plurality of transmitters T including other transmitters T. This will be described next with reference to FIG.

  FIG. 7 is a graph showing the difference between the RSSI of the beacon signal from the transmitter T in the initial state at each position and the RSSI of the beacon signal from each transmitter T acquired by the acquisition unit 110 at a certain position. It is. In addition, in FIG. 7, the example of six transmitters, transmitter TA-TF, is shown.

  In this example, three curves C1 showing the difference between the RSSI of the beacon signal from the transmitter T in the initial state at three different positions and the RSSI of the beacon signal from the transmitter T acquired by the acquisition unit 110. ~ C3 is shown. Of these, the RSSI difference indicated by the curve C3 is compared with the RSSI difference indicated by the curves C1 and C2, and only the RSSI difference of the beacon signal from the specific transmitter T is from the other transmitter T. This is greatly different from the RSSI difference of the beacon signal. Specifically, the RSSI difference of the beacon signals from the transmitters TA, TB, TD to TF is relatively small and close (within a range of 0 to 2), while the beacon signal from the transmitter TC Only the RSSI difference is relatively large (5 or more). Therefore, in this case, it can be estimated that an abnormality has occurred in the transmitter TC.

  Also according to such a principle, the abnormal solid detector 121 can detect the transmitter T in an abnormal state. That is, the abnormal solid detection unit 121 compares the RSSI combination of each beacon signal when the beacon signal is transmitted from the transmitter T in the initial state with the RSSI combination of each beacon signal acquired by the acquisition unit 110. However, the transmitter T in an abnormal state may be detected based on the comparison result and the transmitter information acquired by the acquisition unit 110.

  Next, the hardware configuration of the terminal device 100 will be described with reference to FIG. As illustrated in FIG. 8, the terminal device 100 physically has one or more CPUs (Central Processing Units) 21, RAMs (Random Access Memory) 22, ROMs (Read Only Memory) 23, and imaging such as a camera. Device 24, communication module 26 that is a data transmission / reception device, auxiliary storage device 27 such as a semiconductor memory, input device 28 that receives an input of a user operation such as an operation panel (including operation buttons) or a touch panel, an output device 29 such as a display, Moreover, it can be configured as a computer including a reading device 2A such as a CD-ROM drive device. The function of the terminal device 100 in FIG. 2 is controlled by the CPU 21 by, for example, reading one or a plurality of programs stored in a storage medium M such as a CD-ROM with a reading device 2A and taking them into hardware such as a RAM 22. This is realized by operating the imaging device 24, the communication module 26, the input device 28, and the output device 29 under the above, and reading and writing data in the RAM 22 and the auxiliary storage device 27.

  FIG. 9 shows a module of a positioning program for causing a computer to function as the terminal device 100. As shown in FIG. 9, the positioning program P100 includes an acquisition module P110, a detection module P120, a determination module P130, and a positioning module P140. Each module implements the functions of the acquisition unit 110, the detection unit 120, the determination unit 130, and the positioning unit 140 described above with reference to FIG.

  The detection program is provided by being stored in a storage medium, for example. The storage medium may be a flexible disk, CD-ROM, USB memory, DVD, semiconductor memory, or the like.

  Next, with reference to FIG. 10, the operation of the terminal device 100 when performing positioning (positioning method executed by the terminal device 100) will be described.

  FIG. 10 shows an example of processing executed when the terminal device 100 performs positioning. This process is repeatedly executed at a predetermined cycle, for example. Note that each process can be executed by the control unit 150 unless otherwise specified.

  First, the terminal device 100 performs a beacon scan, and acquires the reception levels and BSSIDs of nearby beacons (step S1). Specifically, the acquisition unit 110 receives the beacon signal from the transmitter T located in the vicinity of the terminal device 100, thereby identifying the RSSI of the beacon signal in the terminal device 100 and the BSSID for identifying the transmitter T. To get.

  Next, the terminal device 100 refers to the abnormal individual DB (step S2), and determines whether there is an abnormal individual (step S3). Specifically, the determination unit 130 refers to the abnormal individual DB 171 (FIGS. 3 and 4) and determines whether or not there is a transmitter T in an abnormal state. If there is an abnormal individual (step S3: YES), the terminal device 100 advances the process to step S4. When that is not right (step S3: NO), the terminal device 100 advances a process to step S8.

  In step S4, the terminal device 100 deletes the value of the abnormal individual from the acquired reception level and BSSID, and collates it with the fingerprint. Specifically, the verification unit 141 deletes the RSSI and BSSID of the beacon signal from the transmitter T in an abnormal state out of the RSSI and BSSID acquired in the previous step S1, and the remaining RSSI and BSSID, The fingerprint ID 173 (FIG. 5) is collated and the corresponding place ID is specified. The corresponding location ID may be a location ID determined to have the smallest difference between the acquired RSSI and the RSSI in the fingerprint DB 173. For example, it may be determined that the difference is the smallest when the average value of the differences between the RSSIs is the smallest. As described above, the location ID indicates each position in the node / link structure ((b) in FIG. 1). Therefore, by specifying the location ID, the location of the terminal device 100 in the node / link structure is specified. Is done. Since each position in the node / link structure corresponds to each position of the building 1, the position of the terminal device 100 in the building 1 is specified.

  Next, the terminal device 100 outputs a collation result as a positioning estimation result (step S5). Specifically, the collation unit 141 outputs the position of the terminal device 100 identified in the previous step S4 as a positioning estimation result. Thereby, the positioning which makes the said result the position of the terminal device 100 is performed.

  Next, the terminal device 100 determines whether or not the reliability of the positioning estimation result is greater than or equal to a threshold (step S6). Specifically, the update unit 142 calculates the reliability of positioning in the previous steps S4 and S5, and determines whether or not the calculated reliability is greater than or equal to a predetermined threshold value. For example, as the difference between the acquired RSSI (excluding the RSSI of the beacon signal from the transmitter T in an abnormal state) collated in the previous step S4 and the RSSI in the fingerprint DB 173 is smaller, the reliability of positioning is smaller. Is calculated to be higher. When the reliability of the positioning estimation result is equal to or higher than the threshold (step S6: YES), the terminal device 100 proceeds with the process to step S7. When that is not right (step S6: NO), the terminal device 100 complete | finishes the process of a flowchart.

In order to calculate the above-described reliability, the following method may be employed. That is, the RSSI stored in the fingerprint DB 173 and the RSSI acquired by the acquisition unit 110 are regarded as vectors, respectively, and the smaller the distance between these vectors (Euclidean distance, Mahalanobis distance, Manhattan distance, etc.), the higher the reliability. You may calculate so that it may become high (for example, the reciprocal of the distance between vectors is made into reliability, etc.). The fingerprint DB 173 shown in FIG. 5 will be described as an example. In this example, four types of RSSI combinations (fingerprints) are shown for each location ID as specific numerical values and stored in the fingerprint DB 173. ing. In this case, when the fingerprint vectors are V1_1, V1_2, V2, and V7, each vector can be regarded as the following vector.
V1_1 = [-62, -62, -66, -65, -65, -67]
V1_2 = [-62, -62, -66, -64, -65, -67]
V2 = [-58, -54, -87, -77, -78, -82]
V7 = [− 73, −67, −73, −72, −90, −59]
For example, when RSSI_TA = −72, RSSI_TB = −68, RSSI_TC = −73, RSSI_TD = −73, RSSI_TD = −90, RSSI_TF = −60 is observed at a certain place X, VX including these elements = [− 72, −68, −73, −73, −90, −60] can be created. Although a detailed description of the calculation process is omitted here, the Euclidean distance between VX and V2 is 35.1, and the Euclidean distance between VX and V7 is 2.0. When the reciprocal number is used as the reliability, the reliability when the location X is V2 can be calculated as 1 / 35.1≈0.03, and the reliability when the location X is V7 can be calculated as 1 / 2≈0.5. it can. When the RSSIs are completely matched, the distance between the vectors is 0, and the reciprocal of the distance cannot be calculated. Therefore, in consideration of such a case, for example, a correction such as adding 1 to the distance is performed. The reciprocal number may be calculated as follows.

  In step S7, the terminal device 100 updates the fingerprint based on the acquisition result. Specifically, the update unit 142 includes the RSSI and BSSID acquired in the previous step S1 (here, the RRSI of the beacon signal from the transmitter T in an abnormal state and the BSSID of the transmitter T), The fingerprint DB 173 is updated according to the positioning estimation result output in step S5. The positioning estimation result here is position information for specifying the position where the positioning is performed, and the RSSI includes the RSSI of the beacon signal from the transmitter T in an abnormal state at the position. The fingerprint DB 173 is updated with information (positioning result information) that associates such position information with RSSI. Thereby, in fingerprint DB173, the combination of each position in building 1 and RSSI of the beacon signal from each transmitter T (including transmitter T in an abnormal state) in each position is memorized. Further, in response to the fingerprint DB 173 being updated, the update unit 142 updates the abnormal individual DB 171 (FIGS. 3 and 4). Specifically, it is assumed that the transmitter T described in the abnormal individual DB 171 as being in an abnormal state is not in the abnormal state. In the example shown in FIG. 3, the description related to the transmitter T that was supposed to be in an abnormal state is deleted. In the example shown in FIG. 4, the flag of the transmitter T whose flag is set to “True” because of an abnormal state is set to “False”. After the process of step S7 is completed, the terminal device 100 ends the process of the flowchart.

  In step S8, the terminal device 100 collates the acquired reception level and BSSID with the fingerprint. Specifically, the collation unit 141 collates the RRSI and BSSID acquired in the previous step S1 with the fingerprint DB 173 (FIG. 5) and identifies the corresponding location ID. By specifying the place ID, the position of the terminal device 100 in the building 1 is specified.

  And the terminal device 100 outputs a collation result as a positioning result (step S9). Specifically, the collation unit 141 outputs the position of the terminal device 100 specified in the previous step S8 as a positioning result. Thereby, the positioning which makes the said result the position of the terminal device 100 is performed. After the process of step S9 is completed, the terminal device 100 ends the process of the flowchart.

  As described above, since the processing of the flowchart shown in FIG. 10 is repeatedly executed, if the fingerprint DB 173 and the abnormal individual DB 171 are updated in step S7, there is an abnormal individual in the next loop. It is determined not to be performed (step S3: YES), and positioning can be performed based on the updated fingerprint DB 173 (steps S8 and S9).

  Next, with reference to FIG. 11 and FIG. 12, an operation of the terminal device 100 when detecting the transmitter T in an abnormal state (a detection method executed by the terminal device 100) will be described.

  FIG. 11 shows an overall flow of processing executed when the terminal device 100 detects the transmitter T in an abnormal state. This process is executed with the movement of the terminal device 100 in the building 1, for example. Note that each process can be executed by the control unit 150 unless otherwise specified.

  First, the terminal device 100 performs a beacon scan, and acquires the reception level and BSSID of surrounding beacons (step S10). Specifically, the acquisition unit 110 receives the beacon signal from the transmitter T located in the vicinity of the terminal device 100, thereby identifying the RSSI of the beacon signal in the terminal device 100 and the BSSID for identifying the transmitter T. To get.

  Next, the terminal device 100 detects an abnormal individual (step S20). Specifically, the abnormal solid detection unit 121 detects the transmitter T in the abnormal state using, for example, the method described above with reference to FIGS. 6 and 7.

  Next, the terminal device 100 determines whether there is an abnormal individual (step S30). If an abnormal individual is detected in the previous step S20, it is determined that there is an abnormal individual. If there is an abnormal individual (step S30: YES), the terminal device 100 advances the process to step S40. When that is not right (step S30: NO), the terminal device 100 complete | finishes the process of a flowchart.

  In step S40, the terminal device 100 performs an abnormal status determination. This process is executed by the determination unit 130. This process will be described with reference to FIG.

  As shown in FIG. 12, first, the terminal device 100 determines whether or not there is a place where a beacon signal from an abnormal individual can be observed (step S41). Specifically, the control unit 150 is in the abnormal state detected in the previous step S20 based on the RRSI acquired by the acquisition unit 110 stored in the storage unit 170 and the history of the transmitter information (history information). It is determined whether there is a place where the beacon signal from the transmitter T is received. If there is a place where a beacon signal from an abnormal individual can be observed (step S41: YES), the terminal device 100 proceeds to step S43. When that is not right (step S41: NO), the terminal device 100 advances a process to step S42.

  In step S42, the terminal device 100 outputs “stop” as the abnormal status. Specifically, the determination unit 130 determines that the abnormal state of the transmitter T is “stop” described above with reference to FIG. This is because when the history information acquired with the movement of the terminal device 100 does not include a beacon signal from the transmitter T in which an abnormal state is detected (step S41: NO), the transmitter T This is because it can be determined that no signal is transmitted.

  In step S43, the terminal device 100 determines whether there is a place where the signal strength of the abnormal individual has increased. Specifically, the determination unit 130 determines whether there is a place where the RSSI of the beacon signal from the transmitter T in the abnormal state in the terminal device 100 is large, based on the history information stored in the storage unit 170. The For example, when the RSSI of the beacon signal from the transmitter T is larger than the corresponding threshold value (see FIG. 6), it is determined that there is a place where the RSSI is large. If there is a place where the signal strength of the abnormal individual has increased (step S43: YES), the terminal device 100 proceeds to step S45. When that is not right (step S43: NO), the terminal device 100 advances a process to step S44.

  In step S44, the terminal device 100 outputs “deteriorated” as the abnormal status. Specifically, the determination unit 130 determines that the abnormal state of the transmitter T is “deterioration” described above with reference to FIG. This is because when there is no place where the RSSI of the beacon signal from the transmitter T from which the abnormal state is detected is large in the history information acquired with the movement of the terminal device 100 (step S43: NO), the transmitter T This is because it can be determined that the output of the beacon signal has decreased.

  In step S <b> 45, the terminal device 100 outputs “move” as the abnormal status. Specifically, the determination unit 130 determines that the abnormal state of the transmitter T is “movement” described above with reference to FIG. 3. This is because when there is a place where the RSSI of the beacon signal from the transmitter T in which the abnormal state is detected is large in the history information acquired along with the movement of the terminal device 100 (step S45), the transmitter T is initial. This is because it can be determined that the current installation location has moved to another location.

  After the process of step S45 is completed, the terminal device 100 detects a movement destination (step S46). Specifically, the destination detection unit 122 refers to the history information stored in the storage unit 170, and the location where the RSSI of the beacon signal from the transmitter T in the abnormal state in the terminal device 100 is large is in the abnormal state. It is detected as the destination of the transmitter T. For example, the place where the RSSI of the beacon signal is maximum is detected as the destination of the transmitter T in an abnormal state. This is because it can be estimated that the position where the RSSI of the beacon signal from the transmitter T is the maximum is the position closest to the transmitter T.

  After the process of step S42, S44 or S46 is completed, the terminal device 100 advances the process to step S50 (FIG. 11).

  In step S50, the terminal device 100 registers the abnormal individual information in the abnormal individual DB. Specifically, an abnormality indicating the BSSID of the transmitter T in the abnormal state detected in the previous step S20 and the determination result (abnormal status and destination) of the transmitter T in the abnormal state determined in the previous step S40. Individual information is registered in the abnormal individual DB 171 (FIGS. 3 and 4).

  Next, the effect of the terminal device 100 will be described. In the terminal device 100, positioning is performed based on a combination of RSSIs of beacon signals from a plurality of transmitters T excluding the transmitter T in an abnormal state. For example, the collating unit 141 specifies the RSSI of beacon signals from a plurality of transmitters T excluding the transmitter T in an abnormal state among the RSSIs of the beacon signals acquired by the acquiring unit 110 and the position in the building 1. The terminal device 100 is positioned by referring to the fingerprint DB 173 described in association with the location ID of the beacon and the RSSI of each beacon signal at the location (step S3: YES, steps S4 and S5). The transmitter T in the abnormal state is, for example, a transmitter T that is in a state of movement, loss, deterioration, breakage, etc., and causes a change in the positioning environment. If positioning is performed based on a combination of RSSIs of beacon signals from a plurality of transmitters T including such a transmitter T, accurate positioning may not be possible due to the influence of changes in the positioning environment. There is sex. Since the terminal device 100 performs positioning without using the RSSI of such a beacon signal from the transmitter T, it is not easily affected by changes in the positioning environment. Therefore, positioning can be performed even when a change occurs in the positioning environment.

  Further, the update unit 142 determines the fingerprint DB 173 based on the positioning result information that associates the position information for specifying the position where the positioning is performed with the RSSI of the beacon signal from the transmitter T in the abnormal state at the position. Is updated (step S7). Thereby, the content of fingerprint DB173 can be made to respond to the change of positioning environment. The collation unit 141 refers to the RSSI of the beacon signal acquired by the acquisition unit 110 (here, including the RSSI of the beacon signal from the transmitter T determined to be in an abnormal state) and the updated fingerprint DB 173. By doing so, positioning corresponding to the change of positioning environment can be performed (steps S8 and S9).

  Moreover, the update part 142 updates fingerprint DB173, when the reliability of positioning is a predetermined reliability (step S6: YES, step S7). Thereby, since the reliability of the content of the fingerprint DB173 after an update can be improved, the positioning precision at the time of positioning with reference to the fingerprint DB173 after an update can be improved.

  Each function of terminal device 100 explained above can also be realized by, for example, a positioning program being executed in a computer.

  Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment.

  For example, the terminal device 100 may communicate with a server (not shown) using the communication unit 160. In this case, for example, at least some of the functions of the detection unit 120, the determination unit 130, the positioning unit 140, and the storage unit 170 of the terminal device 100 may be provided on the server side. Accordingly, the processing load on the terminal device 100 can be reduced and the configuration of the terminal device 100 can be simplified. In this case, the system constituted by the terminal device 100 and the server corresponds to the terminal device according to the present invention.

  Further, when the fingerprint DB 173 is updated on the server side, the positioning results (steps S5 and S6) by the terminal device 100 are tabulated on the server side, and the fingerprint DB 173 is stored based on the tabulated data (statistical data). You may make it update. The positioning result by the terminal device 100 here may be, for example, positioning results by a plurality of different terminal devices 100 respectively possessed by different users. Thus, by updating the fingerprint DB 173 based on many positioning results, the reliability of the contents of the updated fingerprint DB 173 can be further enhanced.

  DESCRIPTION OF SYMBOLS 100 ... Terminal device, 110 ... Acquisition part (acquisition means), 120 ... Detection part, 130 ... Determination part (determination means), 140 ... Positioning part (positioning means), 141 ... Collation part (positioning means), 142 ... Update part (Positioning means), 150 ... control unit, 160 ... communication unit, 170 ... storage unit.

Claims (6)

A terminal device that performs positioning in an area where a plurality of transmitters are arranged at predetermined positions,
An acquisition means for acquiring transmitter information for specifying a reception level of the radio signal from the transmitter and the transmitter;
Positioning means for performing positioning based on a combination of reception levels of radio signals from the plurality of transmitters excluding the specific transmitter acquired by the acquisition unit;
Comprising
Terminal device. The positioning means is
The reception level of each radio signal from the plurality of transmitters excluding the specific transmitter among the reception levels of the radio signal acquired by the acquisition means,
A database in which position information for specifying a position in the region and a reception level of each radio signal at the position are described in association with each other;
To perform the positioning by checking
The terminal device according to claim 1. The positioning means updates the database with positioning result information in which position information for specifying a position where the positioning is performed and a reception level of a radio signal from the specific transmitter at the position are associated with each other. ,
The terminal device according to claim 2. The positioning means updates the database when the positioning reliability is equal to or higher than a predetermined reliability.
The terminal device according to claim 3. The positioning means is
The reception level of each radio signal from the plurality of transmitters including the specific transmitter among the reception levels of the radio signal acquired by the acquisition means;
The updated database; and
To perform the positioning by checking
The terminal device according to claim 3 or 4. A computer provided in a terminal device that performs positioning in an area where a plurality of transmitters are arranged at predetermined positions,
An acquisition means for acquiring transmitter information for specifying a reception level of the radio signal from the transmitter and the transmitter;
Positioning means for performing positioning based on a combination of reception levels of radio signals from the plurality of transmitters excluding a specific transmitter acquired by the acquisition means,
Positioning program to function as.

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