JP2020057070A - System and method for identifying person according to mounting position of terminal - Google Patents

Abstract

To provide a system capable of identifying a person from a public packet reception intensity being different according to mounting position of a terminal.SOLUTION: A person identification device includes a device mounting position table storing a mounting position flag for each of terminal IDs, a map table which registers transmitter IDs in each of the mounting position sides per area, transmitter ID retrieval means which retrieves transmitter IDs of the mounting position side of the mounting position flag among the terminal IDs of the terminal by using the device mounting position table for each of terminals which has received the public packet of the transmitter ID in the area by using the map table in a time zone when a person is present in the area, and person identification means which identifies, among one or more terminals, a terminal having a relatively high reception intensity of the public packet of the transmitter ID at the mounting position side, or a terminal having a relatively large number of reception, as the terminal mounted to the person detected being present in the area.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a technique for estimating a position of a person using radio waves of a short-range wireless communication method.

2. Description of the Related Art Conventionally, there is a technique of estimating a position of a person in an indoor space by using a short-range wireless communication type radio wave transmitted from a tag device.
Tag devices that transmit public information packets are placed throughout the indoor space. A person carrying a terminal (for example, a smartphone) moves in the room. Each time the terminal approaches each tag device by the scanner function of the BLE, the terminal receives the advertisement packet. At this time, the terminal acquires the beacon ID and the received signal strength (RSSI: Received Signal Strength Indication) included in the received public information packet and transmits the beacon ID to the position estimation device via the access network.

  The position estimating device estimates, based on the beacon ID and the reception intensity received from the terminal, where the person holding the terminal is located. Specifically, for each of a plurality of predetermined positions, a “fingerprint” in which a set of RSSIs from a plurality of tag devices is measured in advance is used as a learning phase. The reception intensity group for each tag device as the fingerprint is compared with the reception intensity group for each tag device serving as a query received at the current time. Then, the position of the reference point in the reception intensity group of the most similar fingerprint is estimated as the position of the person holding the terminal.

  As another conventional technique, there is a technique of estimating a position of a person in an indoor environment by combining an RGB-D camera and a PDR (Pedestrian Dead Reckoning) technique (for example, see Non-Patent Document 1). According to this technology, a three-dimensional trajectory of a pedestrian (head) measured by an RGB-D camera, a vertical acceleration and a displacement (yaw angle) in a vertical direction acquired by a PDR (acceleration sensor and angular velocity sensor). ), A person is identified by associating those having a high degree of movement similarity. Further, the position information of the PDR having a large error is corrected using the position information acquired by the RGB-D camera.

  Further, as another conventional technique, there is a technique of analyzing a flow line of a person acting in a store (for example, see Patent Document 1). According to this technology, a flow line corresponding to the moving object is generated by the flow line analysis device tracking the moving object included in the video of the inside of the store.

JP 2009-258782A

"Identification of PDR users reflected on RGB-D camera for human position measurement in indoor environment", Research Report Computer Vision and Image Media (CVIM) 2016-CVIM-200 pp.1-6, Jan. 2016., [online], [Search September 10, 2018], Internet <URL: https://ipsj.ixsq.nii.ac.jp/ej/index.php?active_action=repository_view_main_item_detail&page_id=13&block_id=8&item_id=147145&item_no=1 >

  According to the technology described in Non-Patent Document 1, the position of a person is estimated based on pre-learning on the assumption that there is a change in the movement of the person using the PDR. For example, if the person is stationary at the counter in the store to serve customers, no change in the movement of the person is detected, and the person cannot be identified.

Even if the person holding the terminal is at the same position in the room, there is a phenomenon that the radio wave intensity received from the tag device differs depending on the position of the terminal worn by the person. From the viewpoint of the terminal, it is impossible to recognize whether the reception strength is in a state where visibility is good for the tag device or in a state where a shield is interposed.
One cause is that the person wearing the terminal may be a shield against radio waves received from the tag device. For example, when a person wears the terminal on the left side, the radio wave intensity from the tag device on the left side with good visibility is low, but the radio wave intensity from the tag device on the right side where the person himself is a shield is low.
As a result, when trying to identify a person using the beacon ID from the tag device and its reception intensity, the reception intensity becomes weak depending on the position of the terminal worn by the person, and there is a problem that an erroneous determination is made.

  Accordingly, it is an object of the present invention to provide a system and method for identifying a person by using the reception strength of a public information packet that differs depending on the mounting position of a terminal.

According to the present invention, a transmitter for transmitting a public information packet including a different transmitter ID (IDentifier) corresponding to each of a plurality of areas,
A terminal that receives a public relations packet while attached to a person,
Using a photographing device, a person detecting device that detects a time zone in which a person exists in each area,
A personal identification device that acquires a terminal ID and a transmitter ID and a reception strength of a public information packet from a terminal, and identifies whether or not the person detected by the person detection device is a person wearing the terminal. ,
The person identification device
For each terminal ID, a mounting position table storing a mounting position flag based on the position where the person has mounted the terminal,
A map table in which the transmitter ID of the transmitter at each mounting position is registered for each area;
For each terminal that has received a transmitter ID public information packet in the area using the map table during the time period when a person is present in the area, the mounting position of the mounting position flag in the terminal ID of the terminal using the mounting position table for each terminal Transmitter ID search means for searching the transmitter ID of the side,
Among the one or more terminals, a terminal having a relatively high reception strength of a communication packet of the transmitter ID on the mounting position side, or a terminal having a relatively large number of receptions of the communication packet of the transmitter ID on the mounting position side And a person identification unit that identifies the terminal as a terminal attached to a person detected as being present in the area by the person detection device.

According to another embodiment of the system of the invention,
It is also preferable that the person detecting device detects the time zone only when the number of persons detected in the area is equal to or less than a predetermined number.

According to another embodiment of the system of the invention,
It is also preferable that the photographing device is a camera that photographs each area or a LIDER (light detection and ranging) that irradiates each area with a light wave.

According to another embodiment of the system of the invention,
The person detection device detects a time zone in which the person in the area is present in a forward direction,
It is also preferable that the mounting position table of the person identification device has a plurality of sides with respect to the front of the person as the mounting position of the target terminal.

According to another embodiment of the system of the invention,
Regarding the mounting position table of the person identification device, it is also preferable that the plurality of sides are two or more sides located at an equal angle around the person.

According to another embodiment of the system of the invention,
The terminal is equipped with or connected to an angular velocity sensor,
It is also preferable that the person detecting device corrects the detected forward direction of the person based on the angular velocity received from the terminal.

According to another embodiment of the system of the invention,
The terminal is equipped with or connected to an angular velocity sensor or an acceleration sensor,
It is also preferable that the function of the human detection device is stopped when the angular velocity or the acceleration received from the terminal changes by a predetermined threshold or more.

According to another embodiment of the system of the invention,
The transmitter and the terminal are devices based on the same short-range wireless standard of BLE (Bluetooth Low Energy) or iBeacon (registered trademark) or wireless LAN,
The transmitter ID included in the public information packet is also preferably a beacon ID included in the advertising packet.

According to the present invention, a transmitter for transmitting a public information packet including different transmitter IDs corresponding to a plurality of areas,
A terminal that receives a public relations packet while attached to a person,
A person detection device that detects a time zone in which a person exists in each area;
Person identification of a system having a terminal ID, a transmitter ID and a reception intensity of a public information packet from a terminal, and a person identification device for identifying whether a person detected by the person detection device is a person wearing the terminal or not. The method
The person identification device
For each terminal ID, a mounting position table storing a mounting position flag based on the position where the person has mounted the terminal,
A map table in which the transmitter ID of the transmitter on the mounting position side is registered for each area,
For each terminal that has received a transmitter ID public information packet in the area using the map table during the time period when a person is present in the area, the mounting position of the mounting position flag in the terminal ID of the terminal using the mounting position table for each terminal A first step of searching for the transmitter ID of the side;
Among the one or more terminals, a terminal having a relatively high reception strength of a communication packet of the transmitter ID on the mounting position side, or a terminal having a relatively large number of receptions of the communication packet of the transmitter ID on the mounting position side And a second step of identifying the terminal as a terminal attached to a person detected as being in the area by the person detection device.

  According to the system and method of the present invention, it is an object of the present invention to provide a system and method for identifying a person by using the reception strength of a public information packet that differs depending on the mounting position of a terminal.

It is a system configuration diagram in the present invention. It is a floor map showing the indoor space where a person exists. FIG. 4 is an explanatory diagram illustrating a reception intensity of a radio wave based on a mounting position of a terminal. It is explanatory drawing showing the process of a transmitter ID search part and a person identification part. It is an external view showing that a person exists in area S4. It is a graph showing the receiving intensity for every transmitter ID.

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

  FIG. 1 is a system configuration diagram in the present invention.

According to the system of FIG. 1, the system includes a person identification device 1, a transmitter 2, a terminal 3, a person detection device 4, and a photographing device 5.
FIG. 1 shows a situation where a clerk is explaining a product to a customer via a counter inside a store room. Each clerk wears the terminal 3 and moves freely in the room.

[Transmitter 2]
The transmitter 2 is installed in each of a plurality of areas, and transmits a public information packet including a transmitter ID (IDentifier) different for each area.
The transmitter 2 is a tag device of a short-range wireless communication system, and constantly transmits a publicity packet (Advertising Packet). As the short-range wireless communication method, for example, Bluetooth (registered trademark), Zigbee (registered trademark), or wireless LAN is used. Among them, BLE (Bluetooth Low Energy), in which the range of radio waves is narrow, is particularly suitable. As a low-power version of Bluetooth, it operates with about one-third of the power, so it operates for several years even with button batteries. The public information packet is transmitted periodically, for example, at intervals of 100 ms (20 ms to 10.24 s as a standard). Note that iBeacon (registered trademark) based on Apple's OS after iOS7 is also based on BLE.
According to the BLE standard, the transmitter 2 functions as an “advertiser”, and the publicity packet includes a “beacon ID” as the transmitter ID. The beacon ID includes a UUID (Universally Unique Identifier) for identifying the tag module.

  FIG. 2 is a floor map showing an indoor space where a person exists.

  According to FIG. 2, the indoor space of the store is divided into a plurality of areas. For example, an area S where a clerk stays (sits) and an area C where a customer stays (sits) are divided for each counter. Then, assuming that the action recognition target is a clerk, it is recognized whether or not a person exists in each area S. The transmitter 2 is arranged above (or below) the counter in each area.

[Terminal 3]
The terminal 3 receives the publicity packet while being attached to a person. The terminal 3 is, for example, a smartphone possessed by a clerk who is a person whose behavior is to be recognized. When the clerk moves inside the room while wearing the terminal 3, the terminal 3 receives the public information packet transmitted from the nearby transmitter 2. That is, the terminal 3 functions as a scanner in the BLE standard, for example.
The terminal 3 acquires the beacon ID (transmitter ID) and the reception strength included in the public information packet. Then, the terminal 3 transmits its own “terminal ID” and the “reception time”, “beacon ID (transmitter ID)”, and “reception strength” of the public information packet to the person identification device 1.

As another embodiment, the terminal 3 may be equipped with or connected to an angular velocity sensor or an acceleration sensor.
If the person holding the terminal 3 changes direction suddenly, a large angular velocity is detected. The angular velocity is a rotation angle per unit time. That the person changes his or her direction while wearing the terminal 3 means that the reception strength of the public information packet from each transmitter detected by the terminal 3 also changes.
In addition, while the change in acceleration is small when the person holding the terminal 3 is seated, a large value of acceleration is detected when the person suddenly rises. The fact that the person stands up abruptly with the person wearing the terminal 3 means that the reception intensity of the public information packet from each transmitter detected by the terminal 3 also changes.
The terminal 3 may further include a measurement value of the angular velocity sensor or the acceleration sensor in data to be transmitted when the publicity packet is received, and transmit the data to the human detection device 4.

[Photographing device 5]
The image capturing device 5 captures an image around the area. The image capturing device 5 may be, for example, a general camera or a LIDAR (light detection and ranging) that detects an image using a laser.
For example, in the case of an omnidirectional camera, the omnidirectional camera is installed on a ceiling or the like, photographs the room, and transmits an omnidirectional image to the human detection device 4.

[Person detection device 4]
The person detecting device 4 analyzes the presence of a person based on the image detected by the photographing device 5. A person reflected in the image is detected, and a position of the person is detected from the person detection coordinates on the image and the coordinate system of the shooting area in the physical space.
Then, the person detection device 4 detects a time zone in which a person exists for each area. The “area ID” and the “time zone” where the person exists are transmitted to the person identification device 1.
For example, according to FIG. 2, the presence of a person in the time zone is detected in the area S4 as “people is present”, and the presence of a person in the area S5 is not detected in the area S4. Is absent. "

  It is preferable that the person detection device 4 detects the time zone only when the number of persons detected in the area is equal to or smaller than a predetermined number (for example, one). Generally, the counter has only one clerk, so it is sufficient that the terminal 3 can be identified only for that clerk. Conversely, if there are more than a predetermined number (for example, two or more) persons in one area, the person identification for the terminal is not performed.

  Further, the person detection device 4 may detect a time zone in which the person in the area exists in the "forward direction". When there are persons across the customer service counter, the persons existing in the area S4 always face the counter forward. Therefore, it is also preferable to detect a person only when the persons (the clerk and the customer) face each other via the counter. For example, as in areas S4 and C4 in FIG. 2, only when a person is detected in both areas via the counter, it is determined that a person in the area S4 exists forward and the time zone is detected.

As another embodiment, when the data received from the terminal 3 includes the angular velocity and / or the acceleration, the human detection device 4 functions as follows.
(1) When receiving the angular velocity, the person detection device 4 corrects the detected forward direction of the person based on the angular velocity received from the terminal 3.
(2) When the angular velocity or the acceleration is received, the person detecting device 4 stops functioning when the angular velocity or the acceleration received from the terminal 3 changes by a predetermined threshold or more. Thus, it is possible to extract only the time zone in which the person is facing forward.

[Person identification device 1]
The person identification device 1 identifies the terminal 3 possessed by the person reflected in the video.
According to FIG. 1, the person identification device 1 includes a map table 101, a mounting position table 102, a transmitter ID search unit 11, and a person identification unit 12. These functional components are realized by executing a program that causes a computer mounted on the device to function. In addition, the flow of processing of these functional components can be understood as a person identification method.

<Map table 101>
The map table 101 associates beacon IDs transmitted from at least two transmitters with each area ID. Hereinafter, a case where a person wears the terminal 3 on his or her left or right side will be described as an example.
-Beacon ID of the transmitter on the left side of the person present in the area
-Beacon ID of the transmitter on the right side of the person present in the area
Note that the map table 101 only needs to register an optimal beacon ID for each area ID. That is, the beacon ID of the transmitter arranged in the area adjacent to the area is not necessarily limited.

<Mounting position table 102>
The mounting position table 102 stores, for each terminal ID of the terminal 3, a mounting position flag based on the position where the person has mounted the terminal. As the mounting position flag, for example, “right side” and “left side” are associated.
The mounting position is not limited to the two left and right sides, but may be four front, rear, left and right sides, or a plurality of sides (e.g., sides positioned at an equal angle around the person) with respect to the front of the person. Good.

  The mounting position table 102 is updated, for example, about once a day for each clerk. This is because a person does not change the terminal 3 so frequently. Further, the execution time during the day may be fixed, or the update time may be arbitrarily changed.

  FIG. 3 is an explanatory diagram illustrating the reception intensity of the radio wave based on the mounting position of the terminal.

According to FIG. 3, a person (clerk) staying in area S4 wears terminal 3 on his / her waist. Further, for example, it is assumed that each transmitter is arranged for each area as follows.
The transmitter ID of the transmitter located in the area S3: b3
Transmitter ID of transmitter disposed in area S4: b4
Transmitter ID of transmitter disposed in area S5: b5
In the map table 101, for example, regarding the area S4, the beacon ID: b4 of the transmitter on the left side and the beacon ID: b5 of the transmitter on the right side are associated with each other when viewed from the person existing in the area S4. I have.
When the mounting position table 102 specifies that the terminal 3 is mounted on the left side, the reception strength of the beacon ID: b4 of the left transmitter is higher than the reception strength of the beacon ID: b5 of the right transmitter. Is getting higher.
On the other hand, when it is specified in the mounting position table 102 that the terminal 3 is mounted on the right side, the reception strength of the beacon ID: b5 of the right transmitter is equal to the reception strength of the beacon ID: b4 of the left transmitter. It is higher than the strength.
Such a difference in the reception intensity of the public information packet is based on the fact that the person himself is shielding the radio wave.

FIG. 4 is an explanatory diagram illustrating processing of the transmitter ID search unit and the person identification unit.
FIG. 5 is an external view showing that a person exists in the area S4.

<Transmitter ID search unit 11>
The transmitter ID search unit 11 uses the mounting position table 102 for each terminal that has received a transmitter ID publicity packet in the area using the map table 101 during the time period when a person is present in the area. The transmitter ID on the mounting position side of the mounting position flag in the terminal ID is searched.

FIG. 4A is a table showing “reception time”, “terminal ID”, “beacon ID”, and “reception intensity” recorded each time each terminal 3 receives a public information packet. This is received from each terminal.
<Reception time><TerminalID><BeaconID><Receptionstrength>
10:00 e2 b0 -65dBm
10:01 e1 b3 -70dBm
・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・

FIG. 4B is a table showing a time zone in which the presence of a person is detected for each area. This is received from the person detection device 4. According to FIG. 5, for example, in the time zone 10: 00-10: 10, a person exists in the area S4.
<Area ID><TimeZone>
・ ・ ・ ・ ・ ・
S2 9: 45-9: 49
S4 10: 00-10: 10
・ ・ ・ ・ ・ ・

FIG. 4C uses the map table 101 to search for one or more terminals that have received the beacon ID of the transmitter in the area and time zone where the presence of a person has been detected.
According to FIG. 5, in a time period 10: 00-10: 10 during which the presence of a person is detected in the area S4, the terminals e1 and e2 set the beacon ID: b4 and the beacon ID of the area S4 registered in the map table 101. : B5 has been received.
<Terminal ID><beaconID><average reception intensity><timezone>
e1 b4 -65dBm 10: 00-10: 10
e1 b5 -70dBm 10: 00-10: 10
e2 b4 -75dBm 10: 00-10: 10
e2 b5 -70dBm 10: 00-10: 10
・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・

  FIG. 6 is a graph showing the reception intensity for each transmitter ID.

  According to FIG. 6, in the terminal e1, the vertical axis represents the reception intensity [dBm], and the horizontal axis represents the elapsed time. On the horizontal axis, a time zone in which a person is detected in the area S4 by the person detection device 4, for example, is shown. The terminal e1 has a relatively high average reception intensity of the beacon ID: b4 received from the transmitter on the mounting position side.

  Referring back to FIG. 5, the person present in the area S4 during the time zone 10: 00-10: 10 wears either the terminal e1 or e2. At this time, it is identified which terminal the person is wearing.

  Here, using the mounting position table 102, the mounting positions of the terminals e1 and e2 are specified. Here, terminal e1 is on the left and terminal e2 is on the right.

  According to FIG. 4D, since the terminal e1 is mounted on the left side, the terminal e1 derives the average reception strength of the beacon ID: b4 on the left side of the area S4. Further, since the terminal e2 is mounted on the right side, the terminal e2 derives the average reception intensity of the beacon ID: b5 on the right side of the area S4.

  Without considering the mounting position of the terminal 3, when it is determined whether or not the person existing in the area S <b> 4 is the terminal to be mounted only by the reception intensity of the beacon ID: b <b> 4 installed in the counter, it is determined to be the terminal e <b> 2. Misjudgment may occur. Therefore, the terminal e1 detects only the reception intensity of the beacon ID: b4 of the transmitter on the left side of the mounting position, and the terminal e2 detects only the reception intensity of the beacon ID: b5 of the transmitter on the right side of the mounting position. .

<Person identification unit 12>
The person identification unit 12 is, among the one or more terminals, a terminal having a relatively high reception strength of the advertisement packet of the transmitter ID on the mounting position side, or the number of receptions of the communication packet of the transmitter ID on the mounting position side Is identified as a terminal attached to a person whose presence is detected by the person detection device as being in the area.

According to FIG. 4E, by comparing the terminal e1 with the terminal e2, the terminal e1 having a high average reception intensity is identified as a terminal attached to a person existing in the area S4. This is because the reception strength of the terminal existing in the area S4 becomes relatively high.
According to FIG. 5, the terminal e1 having a relatively high reception intensity is identified as a terminal attached to a person whose presence is detected by the person detection device 4 in the area S4.

As described above in detail, according to the system and method of the present invention, it is possible to identify a person by using the reception strength of a public information packet that varies depending on the mounting position of the terminal.
According to the present invention, it is possible to identify a terminal owned by a person even when the person is not walking in the area. In particular, it is suitable for a store clerk who often stays at the counter for waiting on customers or the like.

  For the above-described various embodiments of the present invention, various changes, modifications, and omissions in the scope of the technical idea and viewpoint of the present invention can be easily performed by those skilled in the art. The foregoing description is merely an example, and is not intended to be limiting. The invention is limited only as defined by the following claims and equivalents thereof.

DESCRIPTION OF SYMBOLS 1 Person identification device 101 Map table 102 Mounting position table 11 Transmitter ID search part 12 Person identification part 2 Transmitter 3 Terminal 4 Person detection device 5 Imaging device

Claims (9)

A transmitter for transmitting a public information packet including a different transmitter ID (IDentifier) corresponding to each of the plurality of areas,
A terminal that receives the publicity packet while being attached to a person,
Using a photographing device, a person detecting device that detects a time zone in which a person exists in each area,
A system comprising: a terminal ID, a transmitter ID of the public information packet, and a reception intensity of the communication packet from the terminal, and a person identification device for identifying whether the person detected by the person detection device is a person wearing the terminal. And
The person identification device,
For each terminal ID, a mounting position table storing a mounting position flag based on the position where the person has mounted the terminal,
A map table in which the transmitter ID of the transmitter at each mounting position is registered for each area;
For each terminal that has received a broadcast packet of the transmitter ID in the area using the map table during a time period when a person is present in the area, the mounting position flag in the terminal ID of the terminal using the mounting position table is used for the terminal. Transmitter ID search means for searching for a transmitter ID on the mounting position side;
Among the one or more terminals, a terminal having a relatively high reception strength of the communication ID of the transmitter ID on the mounting position side, or a relatively large number of receptions of the communication packet of the transmitter ID on the mounting position side A system comprising: a person identification unit that identifies a terminal as a terminal attached to a person detected as being in the area by the person detection device. The system according to claim 1, wherein the person detecting device detects the time period only when the number of persons detected in the area is equal to or less than a predetermined number. 3. The system according to claim 1, wherein the photographing device is a camera that photographs each area, or a light detection and ranging (LIDER) that irradiates each area with a light wave. 4. The person detection device detects a time zone in which a person in the area exists forward,
The system according to any one of claims 1 to 3, wherein the mounting position table of the person identification device includes, as mounting positions of the target terminal, a plurality of sides with respect to a forward direction of the person. The system according to claim 4, wherein the plurality of sides are two or more sides located at an equal angle around a person in the mounting position table of the person identification device. The terminal is equipped with or connected to an angular velocity sensor,
The system according to claim 4, wherein the person detecting device corrects a detected forward direction of the person based on an angular velocity received from the terminal. The terminal is equipped with or connected to an angular velocity sensor or an acceleration sensor,
The system according to any one of claims 1 to 5, wherein the human detecting device stops functioning when the angular velocity or the acceleration received from the terminal changes by a predetermined threshold or more. The transmitter and the terminal are devices based on the same short-range wireless standard of BLE (Bluetooth Low Energy) or iBeacon (registered trademark) or wireless LAN,
The system according to any one of claims 1 to 7, wherein the transmitter ID included in the public information packet is a beacon ID included in the advertising packet. A transmitter for transmitting a public information packet including a different transmitter ID corresponding to each of the plurality of areas;
A terminal that receives the publicity packet while being attached to a person,
A person detection device that detects a time zone in which a person exists in each area;
A system comprising: a terminal ID, a transmitter ID of the public information packet, and a reception intensity of the communication packet from the terminal, and a person identification device for identifying whether the person detected by the person detection device is a person wearing the terminal. The person identification method of
The person identification device,
For each terminal ID, a mounting position table storing a mounting position flag based on the position where the person has mounted the terminal,
A map table in which the transmitter ID of the transmitter on the mounting position side is registered for each area,
For each terminal that has received a broadcast packet of the transmitter ID in the area using the map table during a time period when a person is present in the area, the mounting position flag in the terminal ID of the terminal using the mounting position table is used for the terminal. A first step of searching for a transmitter ID on the mounting position side;
Among the one or more terminals, a terminal having a relatively high reception strength of the communication ID of the transmitter ID on the mounting position side, or a relatively large number of receptions of the communication packet of the transmitter ID on the mounting position side Performing a second step of identifying the terminal as a terminal attached to a person detected as being present in the area by the person detection device.

Images