JP7009260B2 - Position estimation system, position estimation method and program - Google Patents

Description

The present invention relates to a position estimation system, a position estimation method, and a program for estimating the position of a mobile terminal carried by a security guard during security work using a beacon.

Conventionally, there is a position estimation technique using a beacon. For example, Patent Document 1 below discloses a transmitter detection system including a beacon that emits radio waves, an information terminal that executes processing depending on the reception status of radio waves, and a server that is communicatively connected to the information terminal.

In the technique described in Patent Document 1, the difference between the intensity of the radio wave received by the reference terminal at a specific point and the intensity of the radio wave received by the terminal used at the specific point is obtained between the models of the information terminals. It is described that the threshold value (radio wave condition) used for measuring the distance between the beacon and the information terminal is set for each information terminal in consideration of the difference in the radio wave reception sensitivity of the above.

Japanese Unexamined Patent Publication No. 2017-50600

However, when many types of mobile terminals are used, it is a heavy burden for the administrator to preset the optimum threshold value for each mobile terminal.

In view of the above circumstances, an object of the present invention is that when the position of a mobile terminal is estimated using a beacon, the threshold value of the received signal strength used for the position estimation can be easily set for each mobile terminal. To provide a position estimation system, a position estimation method and a program.

In order to achieve the above object, the position estimation system according to one embodiment of the present invention includes a plurality of signal transmitters installed in the space to be managed and a mobile terminal carried by a worker moving in the space. It is a system that estimates the position of the worker. The signal transmitter has a transmitter that transmits a signal including identification information of the signal transmitter. The mobile terminal has a short-range communication unit, a storage unit, a threshold value setting unit, and a position estimation unit. The short-range communication unit receives the signal from the signal transmitter. The storage unit records the identification information included in the signals received from the plurality of signal transmitters in chronological order as detection data in association with the information indicating the received signal strength of the signal, and serves as a reference. The detection data acquired in advance in the space by a predetermined mobile terminal is stored as reference data. The threshold setting unit extracts from the reference data and the detection data a combination of the reference data and the detection data in which at least one of the identification information matches, and determines the strength of the received signal between the extracted data. Based on the difference, the threshold value for position estimation is set. In the position estimation unit, when the received signal strength indicated by the detection data is equal to or higher than the threshold value, there is a worker who carries the mobile terminal around the signal transmitter having the identification information corresponding to the received signal strength. I presume that.

With this configuration, data that matches the signal transmitter of the signal receiver is extracted from the reference data and detection data, which are the time-series reception histories of the reference terminal and the terminal used, which are the reception histories of the plurality of signal transmitters. By setting the threshold value based on the data, the threshold value setting process can be performed during the actual position estimation process, and the burden on the administrator regarding the threshold value setting is reduced.

The threshold setting unit extracts from the reference data and the detection data a combination of the reference data and the detection data in which the order of the identification information that is continuous in the time series matches, and the above-mentioned intervening data. The above threshold value may be set based on the difference in received signal strength.

As a result, by extracting the points where the movement direction or the movement path matches between the reference terminal and the terminal used from the reference data and the detection data, the difference in signal strength between the terminals can be grasped more accurately and the threshold value can be determined. Can be set.

The threshold setting unit extracts a combination of the reference data and the detection data that match one specific identification information from the reference data and the detection data, and determines the strength of the received signal between the extracted data. The above threshold value may be set based on the difference.

As a result, by extracting from the reference data and the detection data the points where the reference terminal and the terminal used pass through the same signal transmitter location, the difference in signal strength between the terminals can be grasped more accurately. You can set a threshold.

The storage unit may store the priority of each signal transmitter in association with the identification information. In this case, when the combination of the reference data and the detection data that matches between the reference data and the detection data is extracted for different identification information or a sequence of identification information, the threshold setting unit is among them. The above threshold may be set based on the data including the identification information associated with the highest priority.

Here, the priority is set higher, for example, as a signal transmitter (for example, a signal transmitter installed in a room entrance / exit or a narrow passage) in which a guard is likely to pass in front of the space. As a result, the possibility of extracting matching data is increased, so that the threshold setting can be made more efficient.

The storage unit may store the number of cases in which the reference data and the detection data match each of the identification information or the order sequence of the identification information. In this case, when the threshold setting unit extracts a plurality of combinations of the reference data and the detection data that match between the reference data and the detection data for the same identification information or the order of the identification information, the data. Of these, the threshold value may be set based on the average value of the received signal strengths of the data having a large number of matches.

As a result, the reliability of the threshold value can be further improved by setting the threshold value based on the average value of the data that matches a plurality of cases.

The position estimation system according to another embodiment of the present invention can communicate with a plurality of signal transmitters installed in a space to be managed, a mobile terminal carried by a worker moving in the space, and the mobile terminal. It has a management device and estimates the position of the worker. The signal transmitter has a transmitter that transmits a signal including identification information of the signal transmitter. The mobile terminal has a short-range communication unit that receives the signal from the signal transmitter, the identification information included in the signals received from the plurality of signal transmitters, and information indicating the received signal strength of the signal. It has a communication unit that is associated with each other and sequentially transmits as detection data to the management device. The management device has a storage unit, a threshold value setting unit, and a position estimation unit. The storage unit stores the detection data received from the mobile terminal in time series, and stores the detection data previously acquired in the space by a predetermined mobile terminal as a reference as reference data. The threshold setting unit extracts from the reference data and the detection data a combination of the reference data and the detection data in which at least one of the identification information matches, and determines the strength of the received signal between the extracted data. Based on the difference, the threshold value for position estimation is set. In the position estimation unit, when the received signal strength indicated by the detection data is equal to or higher than the threshold value, there is a worker who carries the mobile terminal around the signal transmitter having the identification information corresponding to the received signal strength. I presume that.

A position estimation method according to another aspect of the present invention uses a plurality of signal transmitters installed in a space to be managed and a mobile terminal carried by a worker moving in the space, and is used by the worker. It ’s a method of estimating the position.
From the above signal transmitter, a signal including the identification information of the signal transmitter is transmitted, and the signal is transmitted.
The mobile terminal receives the signal from the signal transmitter and receives the signal.
The identification information included in the signals received from the plurality of signal transmitters is associated with the information indicating the received signal strength of the signal and stored as detection data in chronological order.
From the reference data, which is the detection data previously acquired in the space by the predetermined mobile terminal as the reference, and the stored detection data, the reference data and the detection data in which at least one of the identification information matches. Extract the combination of
Based on the difference in the received signal strength between the extracted data, the threshold value for position estimation is set.
When the received signal strength indicated by the detected data is equal to or higher than the threshold value, it includes presuming that there is a worker carrying the mobile terminal around the signal transmitter having the identification information corresponding to the received signal strength. ..

The program according to another embodiment of the present invention can communicate with a plurality of signal transmitters installed in the space to be managed, and can be used as a mobile terminal carried by a worker moving in the space.
A step of receiving a signal including identification information of the signal transmitter transmitted from the above signal transmitter, and
A step of associating the identification information included in the signals received from the plurality of signal transmitters with the information indicating the received signal strength of the signal and storing the information as detection data in chronological order.
A step of storing the detection data acquired in advance in the space by a predetermined mobile terminal as a reference as reference data, and
A step of extracting a combination of the reference data and the detection data in which at least one of the identification information matches from the reference data and the detection data, and
Based on the difference in the received signal strength between the extracted data, the step of setting the threshold value for position estimation and the step.
When the received signal strength indicated by the detected data is equal to or higher than the threshold value, a step of presuming that there is a worker carrying the mobile terminal around the signal transmitter having the identification information corresponding to the received signal strength, and To execute.

As described above, according to the present invention, when the position of the mobile terminal is estimated using the beacon, the threshold value of the signal strength used for the position estimation can be easily set for each mobile terminal. However, the effect does not limit the present invention.

It is a figure which showed the structure of the position estimation system which concerns on one Embodiment of this invention. It is a figure which showed the hardware configuration of the center server which concerns on one Embodiment of this invention. It is a figure which showed the structure of the functional block of the center server, the mobile terminal, and the beacon terminal which concerns on one Embodiment of this invention. It is a figure explaining the threshold value set by the center server which concerns on one Embodiment of this invention. It is a figure which showed the relationship between the moving direction of the guard carrying a mobile terminal and the received signal strength in one Embodiment of this invention. It is a figure which showed the example of the database of the identification information and the position information of the beacon terminal stored in the center server which concerns on one Embodiment of this invention. It is a figure which showed the table of the movable route (path) condition of the guard between the beacon terminals stored in the center server which concerns on one Embodiment of this invention. It is a figure which showed the example of the reference data (time series data of the signal strength for each beacon terminal received by a reference terminal) stored in the center server which concerns on one Embodiment of this invention. It is a figure which showed the example of the detection data (time-series data of the signal strength for each beacon terminal received by the mobile terminal of a security guard) stored in the center server which concerns on one Embodiment of this invention. It is a figure which showed the other example of the detection data stored in the center server which concerns on one Embodiment of this invention. It is a figure which showed the other example of the detection data stored in the center server which concerns on one Embodiment of this invention. It is a flowchart which showed the flow of the threshold value setting process of the signal strength by the center server which concerns on one Embodiment of this invention. It is a figure for demonstrating the threshold value setting process of the signal strength by the center server which concerns on one Embodiment of this invention. It is a figure for demonstrating the threshold value setting process of the signal strength by the center server which concerns on one Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[System configuration]
FIG. 1 is a diagram showing a configuration of a position estimation system according to the present embodiment.

As shown in the figure, this system includes a center server 100, a mobile terminal 200, and a plurality of beacon terminals 300.

The center server 100 is a server installed in a security center operated by a security company, and manages the status of the security guard G and the beacon terminal 300. The center server 100 can communicate with the mobile terminal 200 via the mobile network and the Internet. A security guard is stationed at the security center to monitor the position of the security guard G in the security target facility B, and when an abnormality report is received from the security guard G, the security guard is dispatched to the security target facility B. Necessary measures will be taken.

The security target facility B is, for example, an airport, a station, a commercial facility (department store, supermarket, etc.), an entertainment place, an office of a company, a private residence, or the like.

The mobile terminal 200 is, for example, a smartphone or a security-only terminal, and is carried by a security guard G who guards the security target facility B. In the figure, one guard G and one mobile terminal 200 are shown, but a plurality of guards G and the mobile terminal 200 may exist in the guarded facility B.

A plurality of beacon terminals 300 (A to T) are installed in various places (wall surface, ceiling, fixtures, etc.) of the security target facility B, and transmit a beacon signal. Further, the beacon terminal 300 can communicate with each other and transmit the abnormality information of the beacon terminal 300 or the like to the center server 100.

The mobile terminal 200 receives a beacon signal from each of the beacon terminals 300 and transmits information on the signal strength (received signal strength: RSSI) to the center server 100 via the mobile network and the Internet. The center server 100 estimates which beacon terminal 300 the guard G is in the vicinity of, based on the signal strength. Further, the mobile terminal 200 transmits data or the like acquired by the security guard G during the security work to the center server 100.

[Center server hardware configuration]
FIG. 2 is a diagram showing the hardware configuration of the center server 100. As shown in the figure, the center server 100 includes a CPU (Central Processing Unit) 11, a ROM (Read Only Memory) 12, a RAM (Random Access Memory) 13, an input / output interface 15, and a bus 14 connecting these to each other. To prepare for.

The CPU 11 appropriately accesses the RAM 13 and the like as necessary, and controls the entire block of the center server 100 in an integrated manner while performing various arithmetic processes. The ROM 12 is a non-volatile memory in which firmware such as an OS, a program, and various parameters to be executed by the CPU 11 is fixedly stored. The RAM 13 is used as a work area of the CPU 11, and temporarily holds an OS, various applications being executed, and various data being processed.

A display unit 16, an operation reception unit 17, a storage unit 18, a communication unit 19, and the like are connected to the input / output interface 15.

The display unit 16 is a display device using, for example, an LCD (Liquid Crystal Display), an OLELD (Organic ElectroLuminescence Display), a CRT (Cathode Ray Tube), or the like.

The operation reception unit 17 is, for example, a pointing device such as a mouse, a keyboard, a touch panel, or other input device.

The storage unit 18 is a non-volatile memory such as an HDD (Hard Disk Drive), a flash memory (SSD; Solid State Drive), or another solid-state memory. The OS, various applications, and various data are stored in the storage unit 18.

In particular, in the present embodiment, the storage unit 18 stores an application and other programs and a database for the center server 100 to execute the position estimation process of the guard and the threshold value setting process of the signal strength which is a premise thereof.

The communication unit 19 is a module for wireless communication such as a NIC (Network Interface Card) for Ethernet and a wireless LAN, and is responsible for communication processing with the mobile terminal 200.

Although not shown, the basic hardware configuration of the mobile terminal 200 and the beacon terminal 300 is substantially the same as the hardware configuration of the center server 100.

[Functions and database of each device of the system]
FIG. 3 is a diagram showing the configuration of functional blocks of the center server 100, the mobile terminal 200, and the beacon terminal 300.

(Functional block of center server)
As shown in the figure, the center server 100 has a communication unit 110, a storage unit 120, a threshold value setting unit 130, and a position estimation unit 140 as functional blocks.

Here, in relation to the threshold value setting unit 130, the threshold value set by the center server 100 with respect to the signal strength of the beacon signal received by the mobile terminal 200 in the present embodiment will be described with reference to FIGS. 4 and 5.

As shown in FIG. 4, the threshold value regarding the signal strength of the beacon signal received from the beacon terminal 300 by the mobile terminal 200 is set in the facility by the guard G or the staff of the security target facility B carrying the reference mobile terminal. It can be set based on the signal strength measured when moving for a certain period of time.

The threshold depends on how the security center manager wants to know the position of the guards. For example, when the administrator wants to confirm whether or not the guard G exists within 5 m from the beacon terminal 300, as shown in the figure, the threshold value B is set from the average value of the signal strength at a point 5 m away. Just set it. When a single model is used as the mobile terminal 200, the threshold value set in the reference terminal can be similarly applied to the other mobile terminal 200. In the position estimation process by the center server 100, when the signal strength equal to or higher than the threshold value B is measured from the beacon 1, it is estimated that the guard G is present in the vicinity of the beacon 1 (within approximately 5 m).

On the other hand, when the administrator wants to confirm whether or not the guard is present at a position closer to the beacon 1 (within 1 m from the beacon terminal 300), the guard G is at a point 1 m away as shown in the figure. The threshold value A is set from the average value of the signal strength in. In the present embodiment, of these two threshold values, only the threshold value B is set.

Here, when an attempt is made to set a threshold value while the security guard G is guarding the security target facility B, it is conceivable to use the signal strength obtained at a specific point of the security target facility B. However, depending on the movement route of the guard G, the magnitude of the signal strength received from the beacon terminal 300 may differ even when passing through the same point.

That is, as shown in FIG. 5, at a specific point P, in FIG. A, there is no shield between the mobile terminal 200 and the beacon 1, but in FIG. B, the security guard possessing the mobile terminal 200. The member G becomes a shield, and the radio wave from the beacon 1 is attenuated. Therefore, even at the same point P, the signal strength in FIG. A is measured relatively larger.

Therefore, when simply comparing the signal strength received at a specific point, appropriate data cannot be extracted as a comparison target. Therefore, in addition to the difference in reception sensitivity between models, the movement of the guards as described above. Differences in signal strength due to (movement direction, movement path, etc.) are included, making it impossible to set an appropriate threshold value.

In the present embodiment, the center server 100 determines the threshold value in consideration of such a difference in the movement (movement direction, movement route) of the guard.

Returning to FIG. 3, the communication unit 110 is a communication interface having a function of communicating with the mobile terminal 200, and receives detection data and the like via a mobile network, the Internet, and the like.

The storage unit 120 stores information on the installation position of each beacon terminal 300. FIG. 6 is a diagram showing an example of the installation position information.

As shown in the figure, the installation position information is a database in which the installation position of each beacon terminal 300 in the space of the security target facility B is registered in association with the identification information (beacon ID) of each beacon terminal 300. ..

In the example of the figure, the position (latitude and longitude) in the plane is registered for each beacon terminal 300, but three-dimensional position information may be registered by further adding information such as altitude. Further, not limited to latitude, longitude, and altitude, position information consisting of coordinate values (x, y, z) based on a certain position in a three-dimensional space may be registered. In addition, the installation position of the beacon terminal should be registered under the name of the passage on the first floor (for example, Beacon K), the north side of the room in front (for example, Beacon F), the entrance / exit (for example, Beacon H), and the position of the guard should be estimated. You may do it.

The storage unit 120 also stores a path condition indicating a route that the guard G can move within the security target facility B. FIG. 7 is a diagram showing an example of the path condition table.

In FIG. 1, the solid line connecting the adjacent beacon terminals 300 is a path indicating a route on which the guard G can move, and as shown in FIG. 7, as a path condition, for each beacon terminal 300 (identification information). be registered.

In the registration of the pass condition, another beacon terminal 300 located within a predetermined distance from a certain beacon terminal 300 may be automatically connected, or the administrator may manually register the beacon terminal 300.

Referring to FIG. 1, the guard G can move from the beacon terminal A to the B to the C, but the guard G can move directly from the beacon terminal A to the beacon terminal C without going through the beacon terminal B, I, or the like. It turns out that you can't. Here, in the position estimation process using the path condition, referring to the table of FIG. 7, since the beacon C does not exist at the movable destination of the beacon A, the center server 100 immediately after the beacon terminal A from the detection data. Even if the beacon terminal C is recognized as the route of, it is not estimated that the guard G exists in the vicinity of the beacon terminal C.

Further, the storage unit 120 stores the reference data of the signal strength for each beacon terminal 300. The standard data is obtained by carrying one or more standard mobile terminals by security guard G, the manager, or the staff of the above-mentioned security target facility B, and moving in the facility for a certain period of time in advance before the start of security work. It is the detection data measured in time series, and is the data in which the identification information of the beacon terminal 300 and the signal strength are associated with each other. FIG. 8 is a diagram showing an example of the reference data.

In the figure, in Fig. 1, the manager who possesses the reference terminal opens the door from the passage on the left side of the facility and enters the room in front, and the beacon terminal A → B → C → D → J → G → H. This is an example of the reference data obtained when moving. The character string in which R is added in front of the alphabet that identifies each beacon terminal such as "RA", "RB", and "RC" is when the mobile terminal 200 receives a signal from the beacon terminal 300 identified by each alphabet. The signal strength (R) measured in 1 is shown. As the signal strength, the maximum signal strength (peak value) of the signal strength received from each beacon terminal 300 is adopted, and is stored as numerical data such as dBm (decibel meter).

In the example of the figure, among the movements of the above routes, the movement of the reference data (1) of "RA-> RB-> RC" and "B-> C-> D" from the movement route portion of "A-> B-> C". The reference data (2) of "RB-> RB-> RD" is generated from the route portion, and the reference data (3) of "RC-> RD-> RE" is generated from the movement route portion of "C-> D-> E".

Further, the number of the beacon terminals 300 in the reference data is not limited to the three shown in the figure, but may be four or more (for example, “RA → RB → RC → RD” is one reference data). In this case, the reference data may be stored as a series of time-series data instead of the plurality of types of data as shown in the figure. As the number of beacon terminals included in the reference data increases, it becomes difficult to obtain data that matches the detection data, but the movements of the guards (and managers, etc.) when the reference data and the detection data are acquired are common. Since higher data can be obtained, the reliability of the data to be compared is high.

Further, the reference data may be registered as time-series (sequential sequence) data indicating the movement routes of the plurality of beacon terminals 300 as in the reference data (1) to (3), or only from a single beacon terminal 300. It may be registered as the received data of.

Further, although not shown, for example, the average value of the signal strengths of the plurality of beacon terminals 300 in the reference data is set as the reference threshold value.

Further, although not shown, information regarding the number of times that the detection data (sequential sequence or single) of the same beacon terminal 300 is detected in the reference data is also stored. For example, when any of the reference data (1) to (4) in the figure is detected multiple times at the time of registering the reference data (that is, the administrator or the like has passed the same route multiple times), the reference data is detected. The number of times is recorded.

Further, the storage unit 120 sequentially receives and stores the detection data received by the mobile terminal 200 when the guard G actually moves to the security target facility B from the mobile terminal 200. In the detection data as well, the identification information of the beacon terminal 300 and the signal strength are stored in association with each other, as in the reference data. Further, as the data indicating the time series, data indicating the reception order of each beacon signal may be stored, or data indicating the reception time of each beacon signal may be stored. FIG. 9 is a diagram showing an example of the detection data.

In FIG. 1, the guard G possessing the mobile terminal 200 opens the door from the passage on the left side of the facility and enters the room in front of the facility, and the beacon terminal A → B → C → I → H → A → B → C. This is the detection data obtained when moving in the order of → D → O → E → F → G → D → C → B → A. The data such as "RA" and "RB" indicate the signal strength from each beacon terminal 300 identified by the alphabet, as in the above reference data, and are stored as time series data over time t1 to t17. .. As the signal strength, the maximum signal strength (peak value) of the signal strength received from each beacon terminal 300 is adopted, and is stored as numerical data such as dBm (decibel meter).

Further, the detection data may be stored not as numerical data at the time of peak value measurement but as waveform data indicating a change in signal strength with time.

For example, as shown in FIG. 10, waveform data of signal strength received for each different beacon terminal 300 may be recorded. In this case, the peak value (RA, RB, RC) in each waveform may be recorded together with the reception time (t1, t2, t3).

Further, as shown in FIG. 11, waveform data of signal intensities from a plurality of beacon terminals 300 are extracted at predetermined periods centered on the measurement of each peak value, and are connected and stored as one waveform data, for example. You may. In this case, each waveform data may be appropriately normalized so that the waveform data are connected as naturally as possible. In this case as well, the data indicating the peak value may be recorded together with the reception time data.

Returning to FIG. 3, the threshold value setting unit 130 collates the reference data with the detection data, extracts matching data between the two, and uses the difference in signal strength between the extracted data for position estimation. Set the signal strength threshold.

The data that matches between the reference data and the detection data is data in which at least the identification information of the beacon terminal 300 of the receiving source matches, and specific examples thereof include the following.
(1) Data in which the movement direction of the beacon terminal 300 (that is, the order of identification information of two consecutive beacon terminals 300 in time series) matches between the two data (2) Movement of the beacon terminal 300 between the two data Data in which the route (that is, the order of identification information of three or more consecutive beacon terminals 300 in a time series) matches (3) Data in which a single beacon terminal 300 passed between the two data matches (predetermined beacon). When terminal 300 is detected)

Further, the storage unit 120 may store the priority of each beacon terminal 300 in association with the identification information of the beacon terminal 300. In this case, when a plurality of matching data are extracted between the two data (a plurality of different single identification information or a plurality of different identification information in order), the threshold value setting unit 130 has a priority among them. The threshold value is set using the data including the identification information of the beacon terminal 300 having the highest value. The priority may be set in multiple stages (three or more stages) such as high, medium, and low for all the beacon terminals 300, or the priority is set to two stages and the priority is high for the specific beacon terminal 300. Alternatively, a low priority flag may be set.

Even if the priority is set higher, for example, the beacon terminal 300 (for example, a signal transmitter installed at the entrance / exit of a room or a narrow passage) where the guard G is likely to pass in front of the security target facility B. good. Further, the beacon terminal 300, which is less likely to pass in front of the guard G, may be set to have a lower priority. Further, the beacon terminal 300 in which the beacon signal is detected a plurality of times in the reference data may be set with a high priority. The details of the threshold setting process including the priority will be described later.

When the signal strength of the beacon signal received from the beacon terminal 300 is equal to or higher than the threshold value set by the position estimation unit 140, the security guard G possessing the mobile terminal 200 is in the vicinity of the beacon terminal 300 of the receiving source (for example, 5 m). It is determined that it exists within).

The position estimation unit 140 may further add to the condition of position estimation that the path determination unit 150, which will be described later, determines that the path condition is satisfied.

When the path determination unit 150 receives the detection data from the mobile terminal 200, the beacon terminal 300 described as the source of the beacon signal in the detection data refers to the path condition shown in FIG. 7 and sets the path condition. Determine if it meets or not.

The reliability determination unit 160 determines the reliability of the data in the extraction of the matching data used for setting the threshold value, and extracts the data for setting the threshold value in consideration of this reliability. For example, the reliability determination unit 160 prevents the data determined to have low reliability from being used for setting the threshold value. The details of this process will be described later.

The state management unit 170 manages the position information of the guard G and the abnormality information of the beacon terminal 300 from the detection data received from the mobile terminal 200.

The display output unit 180 outputs the detection data received from the mobile terminal 200 to a display means such as a monitor. As a result, the administrator can grasp the position information of the guard G and the abnormality information of the beacon terminal 300.

(Functional block of mobile terminal)
As shown in FIG. 3, the mobile terminal 200 has a short-range communication unit 210, a communication unit 220, and a signal strength measurement unit 230 as functional blocks.

The short-range communication unit 210 is a communication interface having a function of performing short-range communication with the beacon terminal 300 in the space of the security target facility B, and receives a beacon signal transmitted from the beacon terminal 300 in the space. For short-range communication, for example, Bluetooth (registered trademark) or the like is used.

The communication unit 220 is a communication interface having a function of communicating with the center server 100. The communication unit 220 transmits detection data and the like to the center server 100 via, for example, a mobile phone network or an Internet network.

The signal strength measuring unit 230 is a means for measuring the signal strength of the beacon signal received from the beacon terminal 300. When the beacon signal from the beacon terminal 300 is a radio wave, the signal strength measuring unit 230 detects the amplitude of the received radio wave as the signal strength.

(Functional block of beacon terminal)
As shown in FIG. 3, the beacon terminal 300 has a transmitting unit 310 and a storage unit 320 as functional blocks.

The transmitting unit 310 transmits the above-mentioned beacon signal including the identification information (beacon ID) of the beacon terminal 300 as radio waves or sound waves. The transmission interval of the beacon signal is set to 1 time / second, and the reception interval is set to 1 time (continuous for 5 seconds) / hour, but the present invention is not limited to these.

The storage unit 320 stores the beacon ID, information received from another beacon terminal 300, and the like.

[System operation]
Next, the operation of the position estimation system configured as described above will be described. The operation is executed by the cooperation between the hardware such as the CPU and the communication unit of the center server 100, the mobile terminal 200 and the beacon terminal 300, and the software stored in the storage unit. In the following description, for convenience, unless otherwise specified, the CPU of each device is the main operating unit.

FIG. 12 is a flowchart showing the flow of the signal strength threshold setting process by the center server 100.

As shown in the figure, the CPU 11 (threshold value setting unit 130) of the center server 100 first determines whether or not the detection data has been received from the mobile terminal 200 (step 101). As for the detection data, as described above, the mobile terminal 200 receives the beacon signal from the beacon terminal 300, and based on this, constructs time-series data in which the beacon ID and the signal strength (peak value) are associated with each other. It is generated by doing.

When it is determined that the detection data has been received from the mobile terminal 200 (Yes), the CPU 11 stores the detection data in the storage unit 18 (120) (step 102).

Subsequently, the CPU 11 collates the reference data stored in advance with the received detection data (step 103).

Then, the CPU 11 sets a threshold value regarding the signal strength for the mobile terminal 200 of the receiving source of the detection data based on the difference of the matching data between the reference data and the detection data (step 104).

The threshold value setting process may be performed only when the detection data is first received from the mobile terminal 200, or is executed periodically, for example, at a predetermined time in a day or once every few days. The threshold may be updated. In that case, the detection data most recently received from each mobile terminal 200 may be used for threshold setting.

Here, an example of extracting detection data that matches the reference data will be described.

The CPU 11 performs the following extraction process by collating the reference data shown in FIG. 8 with the detection data shown in FIG.
(A) The detection data in t1 to t3 and the detection data in t6 to t8 are extracted as data that matches the reference data (1).
(B) The detection data in t7 to t9 is extracted as data that matches the reference data (2).
(C) The detection data at t13 is extracted as data that matches the reference data (4).

The CPU 11 compares the detection data extracted in this way with the reference data, and sets a value obtained by changing the difference between the two from the reference threshold value as the threshold value. When a plurality of matching data are extracted as described above, the CPU 11 extracts the data (a) having a large number of matches with the reference data among the above (a) to (c) as a comparison target. do it.

Further, in the case (a), a plurality of detection data (two cases of t1 to t3 and t6 to t8) that match the reference data are extracted, but in this case, the CPU 11 uses any one of them as a comparison target. It may be selected, or a threshold value may be set based on the average value of the signal strengths of those data.

That is, the storage unit 120 stores the number of cases in which the reference data and the detection data match for each identification information of the beacon terminal 300 or for each sequence of identification information, and the CPU 11 (threshold setting unit 130) stores. , When multiple matching data between the reference data and the detection data are extracted for the same identification information or the order of the identification information, the average of the signal strengths of the detection data with the most matching data among the data. A value obtained by varying the reference threshold by the difference between the value and the signal strength of the reference data may be set as the threshold.

As a result, the reliability of the threshold value can be further improved by setting the threshold value based on the average value of the data that matches a plurality of cases.

Further, when the priority of the beacon terminal G in the reference data (4) of FIG. 8 is set high, the CPU 11 (threshold value setting unit 130) may extract the data of the above (c) as a comparison target. ..

On the other hand, in t15 to t17 of FIG. 9, the beacon terminals A, B, and C have passed, and the reference data (1) of FIG. 8 and the passed beacon terminal are the same, but the moving directions are different between the two. Therefore, the CPU 11 (threshold value setting unit 130) does not extract as matching data.

Further, at t8, t9, and t11 of FIG. 9, the beacon terminals C, D, and E have passed, and the reference data (3) of FIG. 8 and the passed beacon terminal match, but the beacon terminal O is on the way. The CPU 11 (threshold setting unit 130) does not extract the data as matching data because the data of the above is included.

Here, the threshold value setting method when the above (a) is extracted as matching data will be specifically described with reference to FIGS. 13 and 14.

When the data as shown in FIG. 13 (A) (actually, not the waveform data but the data of the peak values of the beacon terminals A, B, and C) and the reference threshold value are stored as the reference data, the same figure ( As shown in B), the threshold setting unit 130 calculates the difference between the peak values of the beacon terminals A, B, and C with the matching detection data, and averages the differences obtained at each beacon terminal. However, the new threshold value can be a variation of the reference threshold value.

When waveform data is used as reference data and detection data, the area of the figure formed by the straight line indicating the reference threshold and the waveform of the reference data and the area of the figure formed by the straight line indicating the new threshold and the waveform of the detection data are Other techniques may be used, such as setting new thresholds to be equal.

Next, a specific example of the processing of the reliability determination unit 160 will be described. As described above, the reliability determination unit 160 does not use the data determined to be unreliable for setting the threshold value.

For example, the reliability determination unit 160 sets the reliability low when the detection data contains a mixture of signal strengths higher and lower than the reference data, or when there is a signal strength significantly higher or lower than the reference data. do.

In the example of FIG. 14A, the beacon terminal A measures the signal strength higher than the reference data, but the beacon terminals B and C measure the signal strength lower than the reference data, and the data used for setting the threshold value. Therefore, the reliability determination unit 160 does not use the detection data for the threshold value setting.

Further, in FIG. 3B, the signal strength significantly higher than the reference data is measured only in the beacon terminal B, which is not appropriate as the data used for setting the threshold value. Therefore, the reliability determination unit 160 is concerned. Do not use the detection data for threshold setting. It is assumed that the cause of this is that the guard G has passed very close to the beacon terminal B (for example, within 1 m).

Further, when only the detection data having low reliability is extracted and the threshold value cannot be set, the reliability determination unit 160 may notify the center server 100 of an alert.

[summary]
As described above, according to the present embodiment, when the center server 100 estimates the position of the mobile terminal 200 by using the beacon signal from the beacon terminal 300, the received signal between the models of the mobile terminal 200 It is possible to more accurately grasp the difference in intensity based on the reception mode (movement direction, movement path, etc.) and set the signal strength threshold value, thereby making the position of the mobile terminal 200 (guard G) more accurate. It can be estimated well.

[Modification example]
The present invention is not limited to the above-described embodiment, and can be variously modified without departing from the gist of the present invention.

In the above-described embodiment, the center server 100 is responsible for the threshold setting process and the position estimation process, but the mobile terminal 200 may be responsible for each of the processes. In this case, the mobile terminal 200 has a functional block corresponding to the storage unit 120, the threshold value setting unit 130, and the position estimation unit 140, as well as hardware and a program. The mobile terminal 200 may transmit the position information of the guard G who carries the mobile terminal 200, which is estimated by the position estimation process, to the center server 100.

Further, in the above-described embodiment, the center server 100 stores the path condition shown in FIG. 7 and has the path determination unit 150. When the center server 100 receives the detection data from the mobile terminal 200, the path condition is referred to. Therefore, it is determined whether or not the beacon terminal 300 described as the source of the beacon signal in the detection data satisfies the path condition. However, the mobile terminal 200 may have the path determination unit and the path conditions. In this case, the mobile terminal 200 transmits the detection data to the center server 100 when the path determination unit determines that the detection data satisfies the path condition, and when it is determined that the path condition is not satisfied, the mobile terminal 200 transmits the detection data to the center server 100. , Do not send the detection data to the center server 100.

Further, in the present embodiment, the position estimation of the guard during the security work has been described using this system, but the scope of application of the present invention is not limited to this. For example, it can be applied to the position estimation of workers who work at various sites such as staff of airports and department stores and cleaners who perform cleaning work.

Among the inventions described in the claims of the present application, the invention described as "position information estimation method" is one in which at least one device such as a computer automatically performs each step by information processing by software. This is not something that humans do using devices such as computers. That is, the "position information estimation method" is a position information estimation method by computer software, and is not a method in which a human operates a calculation tool called a computer.

11 ... CPU
18.120 ... Storage unit 19.110 ... Communication unit 130 ... Threshold setting unit 140 ... Position estimation unit 100 ... Center server 200 ... Mobile terminal 300 ... Beacon terminal B ... Security target facility G ... Security guard

Claims (6)

A position estimation system that includes a plurality of signal transmitters installed in a space to be managed and a mobile terminal carried by a worker moving in the space, and estimates the position of the worker.
The signal transmitter is
It has a transmitter that transmits a signal including the identification information of the signal transmitter.
The mobile terminal is
A short-range communication unit that receives the signal from the signal transmitter,
The identification information included in the signals received from the plurality of signal transmitters is associated with the information indicating the received signal strength of the signal and stored in time series as detection data, and a reference mobile device different from the mobile terminal is used . A storage unit that stores the identification information included in the signals received from the plurality of signal transmitters acquired in advance in the space by the terminal as reference data in association with the information indicating the received signal strength of the signal. ,
From the reference data and the detection data, a combination of the reference data and the detection data in which the order of the identification information that is continuous in the time series matches is extracted, and the difference in the received signal strength between the extracted data is extracted. A threshold setting unit that sets a threshold for position estimation based on
When the received signal strength indicated by the detection data is equal to or higher than the threshold value, the position estimation unit presumes that there is a worker carrying the mobile terminal around the signal transmitter having the identification information corresponding to the received signal strength. And has a position estimation system. A position estimation system that includes a plurality of signal transmitters installed in a space to be managed and a mobile terminal carried by a worker moving in the space, and estimates the position of the worker.
The signal transmitter is
It has a transmitter that transmits a signal including the identification information of the signal transmitter.
The mobile terminal is
A short-range communication unit that receives the signal from the signal transmitter,
The identification information included in the signals received from the plurality of signal transmitters is associated with the information indicating the received signal strength of the signal and stored in time series as detection data, and a reference mobile terminal different from the mobile terminal is used. A storage unit that stores the identification information included in the signals received from the plurality of signal transmitters acquired in advance in the space in advance as reference data by associating the identification information with the information indicating the received signal strength of the signal.
From the reference data and the detection data, a combination of the reference data and the detection data in which at least one of the identification information matches is extracted, and based on the difference in the received signal strength between the extracted data, the said A threshold setting unit that sets a threshold for position estimation,
When the received signal strength indicated by the detection data is equal to or higher than the threshold value, the position estimation unit presumes that there is a worker carrying the mobile terminal around the signal transmitter having the identification information corresponding to the received signal strength. And have
The storage unit stores the priority of each signal transmitter in association with the identification information.
When the combination of the reference data and the detection data that matches between the reference data and the detection data is extracted for different identification information or a sequence of identification information, the threshold setting unit has the highest priority among them. The threshold is set based on the data including the identification information associated with the degree.
Position estimation system. A position estimation system that includes a plurality of signal transmitters installed in a space to be managed and a mobile terminal carried by a worker moving in the space, and estimates the position of the worker.
The signal transmitter is
It has a transmitter that transmits a signal including the identification information of the signal transmitter.
The mobile terminal is
A short-range communication unit that receives the signal from the signal transmitter,
The identification information included in the signals received from the plurality of signal transmitters is associated with the information indicating the received signal strength of the signal and stored in time series as detection data, and a reference mobile terminal different from the mobile terminal is used. A storage unit that stores the identification information included in the signals received from the plurality of signal transmitters acquired in advance in the space in advance as reference data by associating the identification information with the information indicating the received signal strength of the signal.
From the reference data and the detection data, a combination of the reference data and the detection data in which at least one of the identification information matches is extracted, and based on the difference in the received signal strength between the extracted data, the said A threshold setting unit that sets a threshold for position estimation,
When the received signal strength indicated by the detection data is equal to or higher than the threshold value, the position estimation unit presumes that there is a worker carrying the mobile terminal around the signal transmitter having the identification information corresponding to the received signal strength. And have
The storage unit stores the number of cases in which the reference data and the detection data match for each identification information or for each order of the identification information.
When a plurality of combinations of the reference data and the detection data that match between the reference data and the detection data are extracted for the same identification information or the order of the identification information, the threshold setting unit may obtain the data among the data. A threshold is set based on the average value of the received signal strength of the data having a large number of matches.
Position estimation system. A plurality of signal transmitters installed in the space to be managed, a mobile terminal carried by a worker moving in the space, and a management device capable of communicating with the mobile terminal are provided, and the position of the worker can be determined. It is a position estimation system that estimates
The signal transmitter is
It has a transmitter that transmits a signal including the identification information of the signal transmitter.
The mobile terminal is
A short-range communication unit that receives the signal from the signal transmitter,
It has a communication unit that associates the identification information included in the signals received from the plurality of signal transmitters with the information indicating the received signal strength of the signal and sequentially transmits the detection data to the management device.
The management device is
The detection data received from the mobile terminal is stored in time series, and the identification included in the signals received from the plurality of signal transmitters previously acquired in the space by a reference mobile terminal different from the mobile terminal. A storage unit that stores information as reference data by associating information with information indicating the received signal strength of the signal .
From the reference data and the detection data, a combination of the reference data and the detection data in which the order of the identification information that is continuous in the time series matches is extracted, and the difference in the received signal strength between the extracted data is extracted. A threshold setting unit that sets a threshold for position estimation based on
When the received signal strength indicated by the detection data is equal to or higher than the threshold value, the position estimation unit presumes that there is a worker carrying the mobile terminal around the signal transmitter having the identification information corresponding to the received signal strength. And has a position estimation system. It is a position estimation method for estimating the position of the worker by using a plurality of signal transmitters installed in the space to be managed and a mobile terminal carried by the worker moving in the space.
A signal including the identification information of the signal transmitter is transmitted from the signal transmitter.
The mobile terminal receives the signal from the signal transmitter and receives the signal.
The identification information included in the signals received from the plurality of signal transmitters and the information indicating the received signal strength of the signal are associated and stored as detection data in chronological order.
A reference different from the mobile terminal The identification information included in the signals received from the plurality of signal transmitters acquired in advance in the space by the mobile terminal is associated with the information indicating the received signal strength of the signal. From the reference data and the stored detection data, a combination of the reference data and the detection data in which the order of the identification information that is continuous in the time series matches is extracted.
Based on the difference in the received signal strength between the extracted data, the threshold value for position estimation is set.
A position estimation method for presuming that a worker carrying the mobile terminal exists around a signal transmitter having identification information corresponding to the received signal strength when the received signal strength indicated by the detection data is equal to or higher than the threshold value. .. For mobile terminals that can communicate with multiple signal transmitters installed in the space to be managed and are carried by workers moving in the space.
A step of receiving a signal including identification information of the signal transmitter transmitted from the signal transmitter, and
A step of associating the identification information included in the signals received from the plurality of signal transmitters with the information indicating the received signal strength of the signal and storing the information as detection data in chronological order.
A reference different from the mobile terminal The identification information included in the signals received from the plurality of signal transmitters acquired in advance in the space by the mobile terminal is associated with the information indicating the received signal strength of the signal. Steps to store as reference data and
A step of extracting from the reference data and the detection data a combination of the reference data and the detection data in which the order of the identification information that is continuous in the time series matches.
A step of setting a threshold value for position estimation based on the difference in received signal strength between the extracted data, and a step of setting the threshold value.
When the received signal strength indicated by the detection data is equal to or higher than the threshold value, a step of presuming that a worker carrying the mobile terminal exists around a signal transmitter having identification information corresponding to the received signal strength, and a step of estimating. Program to execute.

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