JP4651479B2 - Navigation device and access point information collection method - Google Patents

Description

The present invention relates to a navigation device and an access point information collection method , and more particularly to a mechanism for searching for a location of a wireless access point such as a wireless local area network (LAN) or Bluetooth and collecting it as a database.

  In recent years, an access point such as a wireless LAN or Bluetooth has been installed to provide a wireless Internet connection service to an unspecified number of users. Wireless access points are available in a wide variety of forms, from when ISPs (Internet Services Providers) provide commercial services to restaurants, hotels, public facilities, etc. as free services to customers. .

  Wireless access points are not present in all facilities such as restaurants and hotels, but only a part of them. The wireless access point has a different communication standard for each provider. Therefore, the user can use only the wireless access point that supports the same communication standard as the device owned by the user. In addition, when using a member-based wireless access point, it is necessary to make a contract with a provider providing the service. In other words, paid wireless access points that are not contracted cannot be used.

  For this reason, when a user wants to use a wireless LAN or Bluetooth, the user must first find out where an available wireless access point exists. 2. Description of the Related Art Conventionally, a system for searching the location of a wireless access point on the Internet has been provided. There is also a system for displaying the nearest point among the affiliated wireless access points by inputting their location information from a mobile phone.

Furthermore, in a navigation device that allows a driver to easily reach a desired destination by performing vehicle travel guidance, the vehicle position detected using a self-contained navigation sensor, a GPS (Global Positioning System) receiver, or the like. Based on the above, a technique is also provided in which a wireless access point stored in a storage device is searched and the searched point is displayed on a map (see, for example, Patent Document 1).
JP 2004-340864 A

  However, any of the above conventional techniques searches for and provides a wireless access point registered in advance as a database, and cannot present a wireless access point that is not registered in the database to the user. In recent years, with the spread of wireless LAN and Bluetooth, the number of wireless access points tends to increase rapidly, especially in metropolitan areas. In reality, there has been a problem that there is a large number of wireless access points that cannot be searched because there is a situation in which the restructuring of the database by the operator has not caught up with the increasing pace of new wireless access points.

  The present invention has been made to solve such a problem, and enables a user to search and present more wireless access points including newly installed wireless access points to users. For the purpose.

In order to solve the above-described problems, in the present invention, a current position where a wireless communication unit that performs wireless communication with a wireless access point is detected, and the detected current position is stored in a designated category storage unit. There is a wireless access point around the current location where the wireless communication unit exists, depending on the reception status of the wireless communication unit, when a facility that belongs to the category specified by the user is within a predetermined distance When it is determined that there is a wireless access point, the determined wireless access point is recorded on a recording medium together with its position information.

According to the present invention configured as described above, even if the wireless access point is not registered in the database provided by the operator, the wireless access point whose presence has been confirmed by the search operation using the wireless communication unit is the recording medium. Is recorded from time to time, and can be used for subsequent wireless access point searches. As a result, a larger number of wireless access points including newly installed wireless access points can be searched and presented to the user.
Further, according to the present invention, the search operation is performed only when the user approaches a facility belonging to the category desired by the user, so that only wireless access points related to facilities belonging to the user's desired category can be recorded on the recording medium. it can. Further, since it is not necessary to always perform a search operation, it is not necessary to apply a large load, and power consumption can be reduced.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram illustrating a configuration example of a navigation device to which the access point information collection device according to the present embodiment is applied. The access point information collection device of this embodiment is configured using an in-vehicle navigation device, and FIG. 1 also shows components of the navigation device.

  In FIG. 1, reference numeral 11 denotes a map recording medium such as a DVD-ROM (Digital Versatile Disk-Read Only Memory), which stores various types of map data necessary for map display and the like. Here, the DVD-ROM 11 is used as a recording medium for storing the map data, but other recording media such as a CD-ROM and a hard disk may be used. A DVD-ROM control unit 12 controls reading of map data from the DVD-ROM 11.

  The map data recorded on the DVD-ROM 11 includes a drawing unit composed of various data necessary for map display and a road unit composed of data necessary for various processes such as map matching and route search. . The drawing unit includes POI (Point Of Interest) data representing points of interest such as various facilities. POI data is stored in association with categories such as various restaurants, various retail stores, gas stations, banks, vacation facilities, and accommodation facilities, and landmark information and position information used when displaying the facilities on a map. Is included.

  A road unit corresponds to a road, a lane, or the like that connects information about a node corresponding to a point where a plurality of roads intersect, such as an intersection or a branch, and a node on the road and another adjacent node. Information about the link. That is, the road unit includes a connection node table storing detailed data of all nodes and a link table storing detailed data of links specified by two adjacent nodes.

  The connection node table includes information on the normalized longitude / latitude of each node for each existing node. The normalized longitude / latitude indicates a relative position in the longitude direction / latitude direction with reference to a predetermined section. The link table includes link distance information for each existing link. The link distance information indicates the actual distance of the actual road corresponding to the link.

  Reference numeral 13 denotes a position measurement unit that measures the current position of the vehicle (corresponding to the position detection unit of the present invention), and includes a self-contained navigation sensor, a GPS receiver, a position calculation CPU, and the like. The self-contained navigation sensor includes a vehicle speed sensor (distance sensor) that outputs a single pulse for each predetermined travel distance to detect the travel distance of the vehicle, and an angular velocity sensor such as a vibration gyro that detects the rotation angle (movement direction) of the vehicle. (Relative orientation sensor). The self-contained navigation sensor detects the relative position and direction of the vehicle using these vehicle speed sensor and angular velocity sensor.

  The position calculation CPU calculates the absolute own vehicle position (estimated vehicle position) and vehicle direction based on the relative position and direction data of the own vehicle output from the self-contained navigation sensor. The GPS receiver receives radio waves transmitted from a plurality of GPS satellites by a GPS antenna and performs a three-dimensional positioning process or a two-dimensional positioning process to calculate the absolute position and direction of the vehicle (the vehicle direction is The calculation is based on the current vehicle position and the current vehicle position one sampling time ΔT before).

  Reference numeral 14 denotes a map information memory (corresponding to the map storage unit of the present invention), which temporarily stores map data read from the DVD-ROM 11 under the control of the DVD-ROM control unit 12. That is, the DVD-ROM control unit 12 inputs information on the current vehicle position from the position measurement unit 13 and outputs an instruction to read out a predetermined range of map data including the current vehicle position, thereby displaying a map display or guidance route. Map data necessary for the search is read from the DVD-ROM 11 and stored in the map information memory 14.

  A wireless communication unit 15 performs wireless communication with a wireless access point such as a wireless LAN or Bluetooth. Reference numeral 16 denotes a POI category memory (corresponding to a designated category storage unit of the present invention), which temporarily stores information on a POI category designated by a user through an operation of a remote controller (remote controller) 18 described later. The POI category memory 16 is composed of, for example, a non-volatile semiconductor memory, and the stored information is not erased only by turning off the power of the navigation device. It is possible to do.

  FIG. 2 is a diagram illustrating a transition example of menu images displayed on the display device 28 described later when setting POI category information in the POI category memory 16. First, the remote controller 18 is operated to display the top menu shown in FIG. When the “system information setting” command is selected in the top menu, a submenu shown in FIG. 2B is displayed.

  When the “POI category registration” command is selected in this submenu, a selection screen for setting registration to “ON” or “OFF” is displayed as shown in FIG. When “ON” is selected here, as shown in FIG. 2D, POI categories such as restaurants, inns, public facilities, and transportation facilities are displayed as a list. When the user selects a desired one from the plurality of POI categories, information on the selected POI category is stored in the POI category memory 16. This completes the specification of the POI category.

  When it is desired to change the designation of the POI category, the procedure shown in FIGS. 2A to 2D may be performed in the same manner, and a POI category different from the previous one may be selected from the submenu shown in FIG. If it is desired to eliminate the designation of the POI category, the procedure shown in FIGS. 2A to 2C is performed in the same manner, and “OFF” may be selected on the selection screen shown in FIG.

  Next, 17 is an access point memory (corresponding to the recording medium of the present invention), which stores the wireless access point together with its position information. The access point memory 17 is also composed of, for example, a nonvolatile semiconductor memory. Moreover, you may comprise by other recording media, such as a hard disk. The wireless access point stored in the access point memory 17 can be searched at an arbitrary time point through the operation of the remote controller 18, as will be described later.

  The access point memory 17 stores information on the wireless access point detected by a search operation described later as needed. However, the recorded information is not limited to this, and information on the wireless access point prepared by the service provider of the wireless access point may be stored in advance. In this case, each time a new wireless access point is detected by the search operation, new wireless access point information is sequentially added to the originally stored wireless access point information.

  The remote controller 18 allows the user to set various types of information (for example, a route guidance destination) to the navigation device, various types of operations (for example, menu selection operation, enlargement / reduction operation, manual map scrolling, numerical value input). Etc.) are provided with various operators (buttons, joysticks, etc.). The remote controller 18 is also used to specify a POI category to be registered in the POI category memory 16 and search for a wireless access point stored in the access point memory 17. Reference numeral 19 denotes a remote control interface which receives an infrared signal corresponding to the operation state from the remote control 18.

  Reference numeral 20 denotes a processor (CPU) that controls the entire navigation device including the access point information collection device of the present embodiment. A ROM 21 stores various programs necessary for the operation of the access point information collection device and the navigation device. Reference numeral 22 denotes a RAM which temporarily stores data obtained during various processes and data obtained as a result of various processes.

  The CPU 20 performs the following process according to the program stored in the ROM 21. That is, the CPU 20 determines whether there is a wireless access point around the current position detected by the position measurement unit 13 according to the reception status in the wireless communication unit 15. When it is determined that there is a wireless access point around the current position, the wireless access point is recorded in the access point memory 17 together with the position information so that the wireless access point can be searched thereafter. As described above, the CPU 20 and the ROM 21 constitute the determination unit and the information registration unit of the present invention.

  Here, the search operation of the wireless access point using the wireless communication unit 15 may be always performed while the vehicle is running, but in this embodiment, the POI category registered in the POI category memory 16 is used. And only when you need it. That is, when the current position detected by the position measurement unit 13 approaches the facility belonging to the POI category stored in the POI category memory 16 within a predetermined distance, the CPU 20 Control is performed to perform a search operation by instructing the start of a wireless communication operation. Thus, CPU20 also comprises the control part of this invention.

  Whether or not the current position detected by the position measurement unit 13 has approached a facility belonging to the POI category stored in the POI category memory 16 within a predetermined distance is determined based on the current position detected by the position measurement unit 13. The location information, the facility location information included in the POI data associated with the POI category registered in the POI category memory 16, and the link distance information included in the road layer are used. The facility location information and link distance information are stored in the map information memory 14.

  Whether or not there is a wireless access point around the current position is determined by whether or not the wireless communication unit 15 has received information transmitted from the wireless access point, for example. That is, when the wireless communication unit 15 receives information, it is determined that there is a wireless access point around the current position. Furthermore, taking into account the received electric field strength, it may be determined that a wireless access point exists around the current position only when a received electric field strength equal to or greater than a predetermined value can be detected.

  The wireless access point periodically transmits network identification information such as ESS-ID (Extended Service Set Identifier) and BSS-ID (Basic Service Set Identifier), wireless channel, and information regarding the presence or absence of encryption. The CPU 20 determines whether or not there is a wireless access point in the surroundings depending on whether or not the wireless communication unit 15 has received all or part of the information.

  The ESS-ID is one of network identifiers in a wireless LAN, and is a network name given to avoid interference. This ESS-ID includes information representing the service provider of the wireless access point, information representing whether the service is paid or free, and the like. The BSS-ID is the same as the MAC address of the wireless access point.

  The presence or absence of encryption is information indicating whether or not encryption security technology is applied. An ESS-ID can be set in the wireless access point and the wireless communication unit 15, and the wireless access point can be set so as to communicate only with the wireless communication unit 15 having the same ESS-ID. For this reason, ESS-ID can also be used as a security mechanism of a wireless LAN. However, all users share the same password, which is too weak as a security measure. Therefore, substantial security techniques such as encryption may be used as countermeasures against unauthorized access and information leakage.

  The location information of the wireless access point that the CPU 20 records in the access point memory 17 when it is confirmed that there is a wireless access point around the current location is, for example, the facility included in the POI data that triggered the start of the search operation Position information. As described above, since the search operation is started when the current position of the vehicle approaches the facility of the designated POI category within a predetermined distance, when a wireless access point is found in the search operation, the wireless access point Can be considered to exist at the facility.

  The position information of the wireless access point recorded in the access point memory 17 may be the current position information of the vehicle detected by the position measurement unit 13 (where the wireless communication unit 15 exists). If the location where the wireless communication unit 15 exists is registered when the wireless access point is found by the search operation, it is possible to come to that location and use the service of the wireless access point after the next time. Therefore, it is not always necessary to register the location information of the facility itself where the wireless access point is expected to exist in the access point memory 17, and it is sufficient to register the location information where the service of the wireless access point can be used.

  Here, when it is determined that there is a wireless access point around the current position, the wireless access point is always registered in the access point memory 17, but the present invention is not limited to this. For example, based on the ESS-ID and encryption presence / absence information received by the wireless communication unit 15, it is further determined whether or not a wireless access point existing around the current position is actually usable. Only wireless access points determined to be usable may be registered in the access point memory 17.

  For example, if the service provider of the wireless access point indicated by the ESS-ID is different from the provider affiliated with the user, the supported communication standard may be different, and the wireless access point Is not available. If the wireless communication unit 15 does not support a paid wireless access point service, the wireless access point cannot be used if the service is charged. In addition, when encryption is performed, the wireless access point cannot be used unless the wireless communication unit 15 has key information for decrypting the encryption. In such a case, even if the CPU 20 detects the presence of the wireless access point, it does not register it in the access point memory 17.

  CPU20 and ROM21 also comprise the information retrieval part of this invention. That is, the CPU 20 also performs a process of searching for a wireless access point registered in the access point memory 17 and presenting it to the user according to a program stored in the ROM 21. The search method is not particularly limited. For example, when a wireless access point registered in the access point memory 17 belongs to various POI categories as a result of performing a search by specifying various POI categories in the POI category memory 16, the user The wireless access point belonging to the POI category (for example, any one of restaurant, inn, public facility, transportation facility, etc.) specified by is extracted and displayed on the display device 28.

  Further, when the CPU 20 records the wireless access point and its position information in the access point memory 17, if it is recorded in association with the category information of the wireless access point, so-called peripheral facility search of the wireless access point is performed. You can also. The peripheral facility search is a function of searching for facilities existing in the vicinity of the own vehicle position or the cursor position among facilities corresponding to the POI category designated by the user among a plurality of predetermined POI categories. That is, when a user selects a desired POI category from among a plurality of POI categories, the CPU 20 searches for a facility corresponding to the selected POI category and displays the result on the display screen.

  In the present embodiment, a “wireless access point” is added as a POI category that can be specified by the user in such a peripheral facility search. When a peripheral facility search is performed by specifying a category of a wireless access point, the search results are obtained from the wireless access point name (which may be ESS-ID or the like) and the vehicle position in order from the vehicle position or the cursor center. The distance etc. are displayed as a list. Alternatively, an icon indicating the corresponding wireless access point is displayed on the surrounding map.

  The number of wireless access points to be extracted may be one closest to the own vehicle position or the center of the cursor, or may be n (n> 1) in order from the own vehicle position or the cursor center. Further, all wireless access points within a range that falls within one screen of the map image displayed on the display device 28 when the search is performed may be extracted.

  FIG. 3 is a diagram illustrating an example of transition of an image displayed on the display device 28 when searching for surrounding facilities of a wireless access point. First, the remote controller 18 is operated to display a top menu as shown in FIG. 3A, which is different from FIG. When the command “POI” is selected in this top menu, categories such as convenience stores, parking lots, gas stations, banks, and wireless access points are displayed as a list, as shown in FIG.

  When the category “wireless access point” is selected from the list, a selection screen for “searching” or “registering” the POI is displayed as shown in FIG. When “search” is selected here, the CPU 20 executes a peripheral facility search process for the access point memory 17. As a result, a map image as shown in FIG. In FIG. 3D, 31 is a vehicle position mark, and 32 is an icon indicating a wireless access point detected by the peripheral facility search.

  Next, reference numeral 23 denotes a display controller, which generates map image data necessary for display on the display device 28 based on the map data stored in the map information memory 14. A video RAM 24 temporarily stores map image data generated by the display controller 23. That is, the map image data generated by the display controller 23 is temporarily stored in the video RAM 24, and the map image data for one screen is read and output to the image composition unit 27.

  Reference numeral 25 denotes a menu generating unit that generates and outputs various menu images necessary for performing various operations using the remote controller 18. In this menu image, the menu as shown in FIG. 2 for the user to specify the POI category stored in the POI category memory 16 and the wireless access point stored in the access point memory 17 are searched as shown in FIG. There is an image related to the menu as shown in.

  A mark generator 26 generates and outputs a vehicle position mark displayed at the vehicle position detected by the position measuring unit 13 and various landmarks that display various facilities represented by POI data in an icon format. To do. Various landmarks include icons representing wireless access points.

  The image composition unit 27 performs image composition by superimposing each image data output from each of the menu generation unit 25 and the mark generation unit 26 on the map image data read by the display controller 23 and outputs the resultant image to the display device 28. To do. Thereby, the map information around the host vehicle is displayed on the screen of the display device 28 together with the vehicle position mark and various landmarks.

  Next, the operation of the access point information collecting apparatus according to the present embodiment configured as described above will be described. FIG. 4 is a flowchart showing an operation example of the access point information collecting apparatus according to the present embodiment. In FIG. 4, the CPU 20 determines whether or not a POI category is specified, that is, whether or not POI category information is registered in the POI category memory 16 and its registration is set to ON ( Step S1). If the POI category is not specified or if the registration is set to OFF even if it is specified, the process ends.

  On the other hand, if the POI category is specified and set to ON, the CPU 20 acquires the current position information of the vehicle detected by the position measurement unit 13 (step S2). Then, the current location information, the location information of the facilities included in the POI data associated with the designated POI category and stored in the map information memory 14, and the map information memory 14 are stored. It is determined whether or not there is a POI belonging to the designated category within a predetermined distance from the current position by using the link distance information included in the road layer that is set (step S3).

  If there is no POI belonging to the specified category within a predetermined distance from the current position, the process ends. On the other hand, when such a POI exists, the CPU 20 determines whether or not the wireless LAN of the wireless access point is used by the wireless communication unit 15 (step S4). If a wireless LAN is used, the process ends. On the other hand, if the wireless LAN is not used, a wireless access point search operation using the wireless communication unit 15 is executed (step S5).

  The CPU 20 determines whether or not a wireless access point that can actually be used is found around the current position as a result of the search operation (step S6). If there is no available wireless access point, the process ends. On the other hand, if there is a usable wireless access point, the wireless access point is registered in the access point memory 17 together with the position information (step S7).

  As described above in detail, in the present embodiment, it is determined whether there is a wireless access point around the current position according to the reception status in the wireless communication unit 15, and it is determined that the wireless access point exists. Sometimes, the determined wireless access point is recorded in the access point memory 17 together with the position information. As a result, wireless access points that are not included in the data provided by the operator can be added as needed as a database. Therefore, more wireless access points including newly installed wireless access points can be searched and presented to the user.

  Further, in the present embodiment, it is confirmed whether or not the wireless access point can be used during the search operation, and only the wireless access point determined to be usable is registered in the access point memory 17. However, it is possible to prevent unnecessary registration of wireless access points that cannot be actually used even if they are running. By searching for the wireless access points registered in this way, only the wireless access points that can be used reliably can be notified to the user.

  In this embodiment, the user designates a desired POI category, and the search operation of the wireless access point is performed only when the vehicle is near the POI of the category. Only the wireless access point related to the POI desired by can be registered as a database. Further, since it is not necessary to always perform a search operation, it is not necessary to apply a large load to the CPU 20, and power consumption can be reduced.

  In the above embodiment, the search operation is automatically started when the vehicle approaches the POI of the category specified by the user. However, the CPU 20 manually instructs the user to search through the remote controller 18. The search operation may be started when an instruction is received. In this case, the POI category memory 16 is not necessary.

  For example, in the case where the facility information can be registered in the user memory by specifying the POI category and the facility information that does not exist on the map data such as a convenience store, a parking lot, a gas station, or a bank, A “wireless access point” is added to the POI category that can be specified when performing registration. Then, the CPU 20 controls the search operation to start when the POI category of the wireless access point is designated and the facility information is instructed to be registered.

  Specifically, when menu items are selected according to the procedure of FIGS. 3A to 3C and “Register” is selected on the selection screen of FIG. 3C, the CPU 20 causes the wireless communication unit 15 to be wireless. Control to start the communication operation and perform the search operation. FIG. 5 is a flowchart showing the operation of the access point information collecting apparatus in this case.

  In FIG. 5, the CPU 20 determines whether or not the user has instructed registration of a wireless access point through the operation of the remote controller 18 (step S11). If there is no instruction, the process ends. On the other hand, when there is an instruction for wireless access point registration, the CPU 20 controls the wireless communication unit 15 to execute a wireless access point search operation (step S12).

  The CPU 20 determines whether or not a wireless access point that can actually be used is found as a result of the search operation (step S13). If there is no available wireless access point, the process ends. On the other hand, if there is an available wireless access point, the current position information of the vehicle detected by the position measurement unit 13 is acquired (step S14). Then, the wireless access point is registered in the access point memory 17 together with the current position information (step S15).

  In the above embodiment, an example has been described in which the wireless access point discovered by the search operation is recorded in the access point memory 17 together with its position information. In addition to this information, the wireless access received by the wireless communication unit 15 is also described. You may make it record the parameter from a point. The parameter to be recorded here includes at least one of network identification information such as ESS-ID or BSS-ID, a wireless channel, and encryption presence / absence information.

  Moreover, although the said embodiment demonstrated the example which applies the access point information collection apparatus by this invention to a vehicle-mounted navigation apparatus, this invention is not limited to this. That is, the access point information collection device of the present invention can be similarly applied to any terminal that can detect the current position and includes a wireless communication unit for wireless communication with a wireless access point. As such terminals, mobile phones, PDAs (Personal Digital (Data) Assistants), notebook personal computers, and the like are conceivable.

  In addition, each of the above-described embodiments is merely an example of implementation in carrying out the present invention, and the technical scope of the present invention should not be construed in a limited manner. In other words, the present invention can be implemented in various forms without departing from the spirit or main features thereof.

  The present invention relates to an apparatus and method for searching for the location of a wireless access point such as a wireless LAN or Bluetooth and collecting it as a database, and is suitable for application to a navigation device, for example.

It is a block diagram which shows the structural example of the navigation apparatus to which the access point information collection apparatus which concerns on this embodiment is applied. It is a figure which shows the example of a transition of the menu image displayed on a display apparatus when setting POI category information to POI category memory. It is a figure which shows the example of a transition of the image displayed on a display apparatus when performing the periphery facility search of a wireless access point. It is a flowchart which shows the operation example of the access point information collection apparatus by this embodiment. It is a flowchart which shows the other operation example of the access point information collection apparatus by this embodiment.

Explanation of symbols

13 Position Measurement Unit 14 Map Information Memory 15 Wireless Communication Unit 16 POI Category Memory 17 Access Point Memory 18 Remote Controller 20 CPU
21 ROM
26 Mark Generation Unit 27 Image Composition Unit 28 Display Device

Claims (2)

A wireless communication unit for performing wireless communication with a wireless access point;
A position detection unit for detecting a current position where the wireless communication unit exists;
A determination unit that determines whether or not a wireless access point exists around the current position detected by the position detection unit according to the reception status in the wireless communication unit;
When the determination unit determines that the wireless access point exists, the wireless access point determined by the determination unit is recorded together with the position information on a recording medium so that a wireless access point search can be performed thereafter. An information registration unit to
A map storage unit for storing map data including location information of the facility;
A designated category storage unit for storing a category designated by the user;
Based on the current position information detected by the position detection unit and the position information of the facility belonging to the category stored in the designated category storage unit, the current position is within a predetermined distance from the facility belonging to the category. A navigation device comprising: a control unit that determines whether or not the wireless communication unit has approached, and controls the wireless communication unit to start a wireless communication operation when approaching . A first step in which the navigation device detects a current position of a wireless communication unit that performs wireless communication with a wireless access point by a position detection unit;
A second step in which the navigation device determines whether or not there is a wireless access point around the current position detected in the first step according to a reception situation in the wireless communication unit;
When it is determined in the second step that the wireless access point is present, the navigation device records the determined wireless access point along with its position information on a recording medium, and the subsequent wireless access point search is performed. It has a third step of enabling conditions,
Based on the location information of the facility included in the map data of the navigation device, the current location detected in the first step is the facility belonging to the category related to the user designation stored in the designated category storage unit. When the access point information is detected to be within a predetermined distance, the wireless communication unit starts the wireless communication operation and performs the determination process of the second step . Collection method.

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