COMMUNICATION DEVICE, INFORMATION PROCESSING DEVICE, AND METHOD FOR MANAGING LOCATION INFORMATION

Abstract

To provide a technology capable of easily managing location information of wireless devices to be managed in a wide range of areas, reducing increase in cost.SOLUTION: A communication apparatus detects a wireless device, and calculates a relative location of the detected wireless device, relative to a reference wireless device serving as a reference for location identification, on the basis of an amount of movement of the communication apparatus after the communication apparatus detected the reference wireless device. The communication apparatus associates the calculated relative location, identification information of the detected wireless device, and identification information of the reference wireless device.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a technique for managing location information of wireless devices. [Background technology]

[0002] Systems are being used in logistics, inventory, animal management, and other areas to manage objects and animals using UHF passive RFID tags (hereafter referred to as RFID tags) as wireless devices. RFID tags receive radio waves (electromagnetic waves) emitted from the antenna of an RFID reader and operate using the power generated by them, so they have the advantage of not requiring batteries and can be manufactured thin and inexpensively. However, the communication distance between RFID tags and RFID readers is short, so there is a disadvantage in that RFID tags over a wide area cannot be detected at once.

[0003] Therefore, a method has been proposed for managing the location information of managed objects with RFID tags attached over a wide area by carrying an RFID reader capable of detecting location information and automatically linking the location information when an RFID tag is detected with the ID information of the RFID tag. Patent Document 1 describes a technology for detecting the location information of an RFID reader using GPS. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication 2007-114003 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the method of using GPS to detect the location of an RFID reader is not suitable for indoor use, and the need to install a GPS receiving circuit increases the cost of the RFID reader.

[0006] Therefore, the present invention provides a technique that makes it possible to easily manage the location information of wireless devices to be managed over a wide range while suppressing increases in costs. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, a communication device of the present invention has a power source, detection means for detecting a wireless device, storage means for storing identification information of the wireless device, calculation means for calculating a first relative position of a second wireless device different from the first wireless device with respect to a first wireless device serving as a reference for specifying a position based on an amount of movement of the communication device, and association means for associating the first relative position, the identification information of the second wireless device, and the identification information of the first wireless device, wherein when a position of the communication device at the time of starting up the power source of the communication device is set as an initial position, and when the second wireless device is detected in a state in which the first wireless device has not been detected after the initial position is detected by the detection means, the storage means stores a second relative position of the second wireless device with respect to the initial position, and when the first wireless device is detected after the detection means detects the second wireless device, the calculation means stores a third relative position of the first wireless device with respect to the initial position, indicating the amount of movement of the communication device; The first relative position is calculated based on the second relative position and the third relative position.

[0008] The information processing device of the present invention further includes a receiving means for receiving, from a communication device that has detected a wireless device, identification information of the detected first wireless device and information on a first relative position of the first wireless device with respect to an initial position of the first wireless device; The first relative position information and information on a second relative position from the initial position of a second wireless device that is a reference for identifying a position different from that of the first wireless device; And, fromThe communication device has a calculation means for calculating a third relative position of the second wireless device from the first wireless device, and an association means for associating the third relative position calculated by the calculation means, identification information of the first wireless device, and identification information of the second wireless device, and is characterized in that when the position of the communication device at the time of powering on the communication device is set to the initial position, when the first wireless device is detected in a state in which the second wireless device is not detected after the initial position is detected, the calculation means calculates the third relative position based on the first relative position and a second relative position of the second wireless device with respect to the initial position when the second wireless device is detected after the first wireless device is detected. Effect of the Invention

[0009] According to the present invention, it becomes possible to easily manage the location information of wireless devices to be managed over a wide range while suppressing increases in costs. [Brief description of the drawings]

[0010] [Figure 1] An illustration of an RFID reader 100 [Diagram 2] FIG. 1 is an explanatory diagram of a mobile object carrying an RFID reader 100. [Diagram 3] System diagram of the first embodiment [Figure 4] 1 is a control flowchart of the RFID reader 100 according to the first embodiment. [Diagram 5] FIG. 1 is an explanatory diagram of a display method of the display unit 14 according to the first embodiment; [Figure 6] Control flow chart for improving the accuracy of position information [Figure 7] Control flow chart for improving the accuracy of position information [Figure 8] Charging device 300 for RFID reader 100 [Figure 9] System diagram of the second embodiment [Figure 10]11 is a control flow chart of the RFID reader 100 according to the second embodiment. [Figure 11] 11 is a control flowchart of the server 20 according to the second embodiment. [Figure 12] FIG. 13 is an explanatory diagram of a display method of the display unit 14 according to the second embodiment. [Figure 13] System diagram of the third embodiment [Figure 14] 11 is a control flow chart of the RFID reader 200 according to the third embodiment. [Figure 15] An illustration of a location RFID tag 30 and an item RFID tag 40. [Figure 16] Antenna 115 configuration diagram [Figure 17] Radiation characteristics of antenna 115 [Figure 18] Showing 20 hardware configurations of servers DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, a method for managing location information of wireless devices to be managed according to an embodiment of the present invention will be described in detail with reference to the drawings. In the management method according to this embodiment, a communication device capable of detecting wireless devices is carried by a moving object such as a person or machine, thereby detecting wireless devices present in a wide range. Here, the wireless devices are, for example, RFID tags, and the communication device is, for example, an RFID reader.

[0012] 2, the RFID reader 100 can be worn by a person (animal) (FIG. 2(A)), or attached to a machine such as a drone 401 or an unmanned guided vehicle 501 (FIGS. 2(B) and 2(C)). This allows the RFID reader 100 to be moved over a wide range and to detect RFID tags present over a wide range.

[0013] The RFID reader 100 has a function of supplying UHF electromagnetic waves to the RFID tag to operate the IC chip inside the RFID tag and read out the ID information stored in the memory unit of the RFID tag. In addition, the RFID reader 100 and the RFID tag can wirelessly communicate at a distance of several meters.

[0014] In this embodiment, as shown in Fig. 15(B), an RFID tag attached to a managed object such as an object or an animal is called an object RFID 40. The object RFID tag 40 is used to identify the managed object to which the object RFID tag 40 is attached by ID information stored in the object RFID tag 40. Also, as shown in Fig. 15(A), an RFID tag that serves as a reference for identifying the position of the object RFID tag 40 is called a position RFID tag 30. The RFID reader 100 calculates the relative position of the object RFID tag 40 with reference to the position RFID tag 30, using a movement amount detection sensor 104 described later.

[0015] By displaying information on the relative position of the article RFID tag 40 with respect to the positional RFID tag 30 on the display unit 14 in Fig. 3, the user can grasp the location of the managed object to which the article RFID tag is attached. Details of each process will be described in each of the following embodiments.

[0016] In the description of the embodiment of the present invention, an example will be described in which an RFID tag is used as a wireless device to be detected and an RFID reader is used as a communication device for detecting the wireless device, but the wireless device and communication device are not limited to these. For example, instead of RFID, other wireless communication such as short-range wireless communication such as NFC or Bluetooth (registered trademark) may be used. Or, instead of UHF band RFID, RFID using other frequency bands may be used.

[0017] [First embodiment] 1 shows a circuit block diagram of an RFID reader 100 used in the first embodiment. The RFID reader 100 is controlled by a calculation unit 101 including one or more processors such as a CPU, and an RF control unit 110 outputs UHF-band RF from a TX terminal based on the control of the calculation unit 101. The RF output is amplified by a power amplifier 111, and then unnecessary frequency bands are cut by a low-pass filter 112. The power of the RF output can be variably set by the calculation unit 101. A coupler 113 is used by an RF power detection unit 116 to detect the power.

[0018] The power detection result of the RF power detection unit 116 can be detected by the calculation unit 101 as an RF_Detect signal. The coupler 114 is used to branch the RF output to the antenna 115 and the RF input received from the antenna unit 115. The antenna unit 115 supplies power to the RFID tag and is used to communicate with the RFID tag. The carrier cancellation unit 117 cancels the carrier component of the RF input based on the CARRIER_CANNCEL signal, receives the signal component of the RF input at the RX terminal of the RF control unit 110, and can detect ID information, which is identification information of the RFID tag.

[0019] The calculation unit 101 stores the ID information of the RFID tag detected by the RF control unit 110 in the storage unit 102, and after performing necessary data processing, communicates with the information terminal 10 described in Fig. 3 via the communication unit 103. The storage unit 102 is composed of one or more memories such as ROM and RAM, and stores various data as well as programs to be processed by the calculation unit 101. The communication unit 103 can communicate with the information terminal 10 by wired communication such as Ethernet (registered trademark) or USB, or wireless communication such as wireless LAN or public wireless system.

[0020] The movement amount detection sensor 104 is a sensor equipped with a three-axis acceleration sensor, a gyro sensor, and a geomagnetic sensor, and detects the amount of movement of the RFID reader 100. It is used to calculate the relative position of the reference position RFID tag 30 and the article RFID tag 40. Note that the movement amount detection sensor 104 may use any detection method as long as it can detect the movement distance and direction of the RFID. In the embodiment of the present invention, information combining the movement distance and movement direction (two-dimensional or three-dimensional direction) is treated as the amount of movement.

[0021] The RFID reader 100 automatically detects the ID information of the RFID tags, calculates the relative positions between the RFID tags using the movement detection sensor 104, and associates the ID information of multiple RFID tags with information on the relative positions between the multiple RFID tags. The power supply unit 105 is a circuit used to supply power voltage to the RFID reader 100, and is composed of a battery, a DC-DC converter, etc.

[0022] Fig. 3 is a system diagram of this embodiment. RFID tags are classified into position RFID tags 30 (30a to 30c) used to detect a reference position and article RFID tags 40 (40a to 40f) attached to managed objects. Details of the RFID tags will be described in Fig. 15.

[0023] The RFID reader 100 associates the ID information of the article RFID tag 40, the ID information of the position RFID tag 30, information on the relative position of the article RFID tag 40 with the position RFID tag 30, and the detection time of the article RFID tag 40. Then, the RFID reader 100 transmits the information to the information terminal 10.

[0024] The information terminal 10 is an information terminal such as a smartphone or a PC, which includes a database 11, a database 12, and a display unit 14. The database 11 holds data linking the ID information of the location RFID 30 with the location name, and data linking the ID information of the item RFID 40 with the item name.

[0025] Since it is difficult for users to recognize the ID information of the RFID tag as it is, when the information is displayed on the display unit 14, the ID information is converted into a name based on the database 11 and then displayed. It is also possible to display the RFID ID information directly on the display unit without using the database 11.

[0026] The database 12 holds information received from the RFID reader 100. Specifically, it stores data linking the ID information of the position RFID tag 30, the ID information of the article RFID tag 40, the relative position of the article RFID tag 40 with respect to the position RFID tag 30, and the detection time of the article RFID tag 40. The display unit 14 displays the position information of the article based on a user instruction via an interface (not shown) of the information terminal 10. A specific display method of the display unit 14 will be described with reference to FIG. 5.

[0027] Fig. 4 shows a flowchart of a method for detecting position information of an RFID tag of an article by the RFID reader 100 of this embodiment. When the power of the RFID reader 100 is turned on, the RFID reader 100 starts controlling detection of position information of an article. Each step of the flowchart in Fig. 4 is realized by the calculation unit 101 of the RFID reader 100 executing a program stored in the memory unit 102.

[0028] In S101, the RFID reader 100 sets the position of the device at the time of startup as a reference position, and sets the information of the relative position with respect to the reference position in the storage unit 102 to 0 (x=0, y=0, z=0).

[0029] In S102, the RFID reader 100 calculates an integral value of the amount of movement based on the detection result of the movement amount detection sensor 104, updates information on the relative position with respect to the reference position, and starts control to store the information in the memory unit 102. In S103, the RFID reader 100 periodically operates the RF control unit 110 to communicate with the RFID tag, and starts control to communicate with the RFID tag.

[0030] In S104, the RFID reader 100 judges whether the RFID tag ID information has been acquired from the RFID tag, and if the RFID tag ID information has been acquired, the process proceeds to S105. If the RFID tag ID information has not been acquired, the process of S104 is repeated.

[0031] In S105, the RFID reader 100 determines whether the RFID tag is a position RFID tag 30 or an article RFID tag 40 based on the acquired ID information. As a method for distinguishing between the position RFID tag 30 and the article RFID tag 40, for example, an identifier capable of distinguishing between the position RFID tag 30 and the article RFID tag 40 can be provided in the ID information of the RFID tag. Also, the determination can be made by referring to the database 11 of the information terminal 10. If it is an article RFID tag, the process proceeds to S106, and if it is a position RFID tag, the process proceeds to S108.

[0032] In S106, the RFID reader 100 judges whether a reference position RFID tag has been set. If the reference position RFID tag has not yet been set, such as immediately after the RFID reader 100 is started, the process proceeds to S107, and if the reference position RFID tag has been set, the process proceeds to S113.

[0033] In S107, the RFID reader 100 stores in the memory unit 102 data linking the ID information of the article RFID tag 40, the detection time of the article RFID tag 40, and the relative position of the article RFID tag 40 with respect to the reference position (initial position at startup).

[0034] In S108, the RFID reader 100 stores the ID information of the detected position RFID tag 30 in the memory unit 102 as a reference position RFID tag, and proceeds to S109. In S109, the RFID reader 100 judges whether the position RFID tag is detected for the first time after the start of the RFID reader 100. If the position RFID tag is detected for the first time, the process proceeds to S110, and if it is the second or subsequent time, the process proceeds to S112.

[0035] In S110, the RFID reader 100 executes the following process on the data stored in the storage unit 102 in S107. That is, the relative positions of the position RFID tag 30 and the article RFID tag 40 are calculated based on the information on the relative position of the article RFID tag 40 with respect to the reference position and the information on the relative position of the position RFID tag 30 with respect to the reference position stored in the storage unit 102 in S108. The reference position here is the initial position at the time of startup of the RFID reader 100 (the position stored in S101).

[0036] In S111, the RFID reader 100 executes the following process on the data stored in the memory unit 102 in S107. That is, the RFID reader 100 links the ID information of the article RFID tag 40, the ID information of the position RFID tag 30, the detection time of the article RFID tag 40, and information on the relative position of the article RFID tag 40 with respect to the position RFID tag 30. Then, the RFID reader 100 transmits the information to the information terminal 10. The communication unit 103 is used for the transmission.

[0037] In S112, the RFID reader 100 sets the information of the relative position with respect to the reference position in the memory unit 102 to 0 (x=0, y=0, z=0), and returns to S102. In S113, the RFID reader 100 associates the ID information of the detected item RFID tag 40, the ID information of the position RFID tag 30, the detection time of the item RFID tag 40, and information of the relative position of the item RFID tag 40 with the position RFID tag 30. Then, the RFID reader 100 transmits the information to the information terminal 10.

[0038] The RFID reader 100 repeats the above control until a system termination request is received (S114). As a result, the calculation unit 101 of the RFID reader 100 automatically detects the position information of the RFID tag 40 attached to the managed object and transmits it to the information terminal 10.

[0039] FIG. 5 is a display example displayed on the display unit 14 of the information terminal 10. ToThe illustrated display example displays location information of managed items based on information from databases 11 and 12. In the display example of Fig. 5, the location RFID tag 30 is displayed as a double circle on the display unit 14, and the item RFID tag 40 is displayed as a single circle.

[0040] FIG. 5(A) shows a display example of the display unit 14 when the user instructs the information terminal 10 to display information on the XX building, 1F North. In the database 12, first, for the ID information 40a-40c (items a-c) of the item RFID tag 40 linked with the ID information 30a (XX building, 1F North), data is selected for each ID that has the closest item detection time to the time XX. Then, by referring to the relative position information between the item and the position RFID, the display unit 14 can display the position information of the items a-c based on the position of the XX building, 1F North. The user can grasp the actual location of the item by looking at the display information on the display unit 14 and the placed position RFID tag.

[0041] FIG. 5(B) shows an example of the display on the display unit 14 when the user instructs to display XX Building 7F at time XX. Here, an example of the display is shown in which items d and e are on a different floor from XX Building 7F. If the distance in the height direction between items d and e and the position RFID tag 30c of XX Building 7F is greater than a predetermined set value, it can be detected that items d and e are on a different floor from XX Building 7F. By displaying items on different floors as dotted circles on the display unit 14, it is shown to the user that items d and e are not on the same floor as the position RFID tag 30c. Based on the information on the relative position with the position RFID tag 30c, it is determined that item d is on an upper floor of XX Building 7F and item e is on an upper floor of XX Building 7F. Ru7 It indicates that it is on the floor below F.

[0042] FIG. 5C shows an example of display on the display unit 14 when a user instructs to display item c at time YY. For the data of the position RFID tag 30a (X△ Building 1F North) and the position RFID tag 30b (X△ Building 1F East) linked to the ID information 40c (item c) in the database 12, data with the time of detection of the item closest to time YY is selected for each ID. Then, by referring to the information on the relative position between the item and the position RFID, the position of the item c based on the positions of the position RFID tag 30a of X△ Building 1F North and the position RFID tag 30b of X△ Building 1F East can be displayed on the display unit 14. In this display method, the user can grasp the location of the item c by using multiple position RFID tags as markers. The display showing the position RFID tag 30 shows the position RFID tag 30a linked to the data of the detection of item c at the time closest to time YY with a solid double circle, and the other position RFID tags 30b with a dashed double circle. In this display method, the user can preferentially refer to the location information of the item that was detected closest to the specified time YY.

[0043] As described above, in the method for managing the position information of an article according to the first embodiment, the position RFID tag 30 is used as a reference for identifying the position used in managing the article. Therefore, it is not necessary to associate quantitative position information with the position RFID tag 30 and store it. Therefore, the user can easily introduce the position information detection system 1 by simply attaching the article RFID tag 40 to the object to be managed and installing the position RFID tag 30.

[0044] Furthermore, when a user tries to grasp the location of an item, it is difficult for the user to intuitively grasp the location of the item even if quantitative coordinates indicating the location are displayed on the display unit 14. By displaying the location of the item based on the location of one or more positional RFID tags 30, the user can easily grasp the location of the item.

[0045] Furthermore, the position RFID tag 30 does not require a connection to a power cable, etc. Therefore, the position RFID tag 30 can be installed in a simple manner, such as by placing it on the floor or attaching it to a wall, and a position information detection system can be easily introduced not only indoors but also outdoors.

[0046] Furthermore, the positional RFID tag 30 does not need to be placed in a fixed location, and by placing it on the bed of a truck, for example, it can be used to detect the positional information of an item in the bed of a moving truck.

[0047] As described above, the management system for managing location information of items in this embodiment can be installed inexpensively and easily both indoors and outdoors, and can manage the location information of managed objects equipped with RFID tags over a wide range.

[0048] [Second embodiment] 9 is a system diagram of the second embodiment. The system of this embodiment differs from the first embodiment in that the server 20 performs data processing required for position detection instead of the RFID reader 100, and that the detection time of the position RFID is also linked to and managed in the database 12. Note that the same reference numerals are used for the same components as in the first embodiment, and the description thereof will be omitted.

[0049] In the system 2 of Fig. 9, multiple RFID readers 100 (100a, 100b, ...) are connected to a server 20. The RFID readers 100 link the ID information of the RFID tags (item RFID tags 40 and position RFID tags 30), the relative positions of the RFID tags with respect to a reference position described later, and the detection times of the RFID tags, and transmit data to the server 20. Note that the time display in Fig. 9 indicates that the detection times progress in the order of 10 → 11 → 12 → 20 → 21 → 31.

[0050] 18 shows a hardware configuration of the server 20 of this embodiment. The storage unit 1801 is configured with one or more memories such as ROM and / or RAM, and stores programs for performing various operations described later and databases described later. Note that, in addition to memories such as ROM and RAM, the storage unit 1801 may also be a storage medium such as a flexible disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a CD-R, a magnetic tape, a non-volatile memory card, or a DVD.

[0051] The control unit 1802 includes the calculation unit 23 shown in Fig. 9 and is configured by, for example, one or more processors such as a CPU or an MPU, an ASIC (Application Specific Integrated Circuit), a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array), etc. Here, CPU is an acronym for Central Processing Unit, and MPU is an acronym for Micro Processing Unit. The control unit 302 controls the entire device by executing a program stored in the storage unit 301.

[0052] The input unit 1803 receives various operations from the user. The output unit 1804 outputs various information to the user. Here, the output by the output unit 1804 includes at least one of display on a screen, audio output by a speaker, vibration output, and the like. Note that both the input unit 1803 and the output unit 1804 may be realized by one module, such as a touch panel. The communication unit 1805 can execute wired or wireless communication, and the server 20 can communicate with an RFID reader using the communication unit 1805.

[0053] The system diagram of Fig. 9 illustrates a database stored in the storage unit 1801 of the server 20. As will be described later in the explanation of Fig. 11, the server 20 distinguishes between the position RFID tag 30 and the article RFID tag 40. When the server 20 receives data of the position RFID tag 30 from the RFID reader 100, the server 20 stores the data in the database 21a, and when the server 20 receives data of the article RFID tag 40, the server 20 stores the data in the database 21b. The databases 21a and 21b store ID information of the RFID reader 100 in order to determine which RFID reader received the data. The databases 21a and 21b are temporary storage databases used by the server 20 to process data and create the database 12.

[0054] The database 11 of the server 20 stores the installation time of the position RFID tag 30 in addition to the location name of the position RFID tag 30. Here, the position RFID tag 30 with ID information 30a shows data for a case where the tag was installed on the north side of the 1st floor of the X△ building at time 10, and then moved to the 2nd floor of the X△ building at time 20 and installed there. The position RFID tag 30 with ID information 30b shows that the tag was installed on the east side of the 1st floor of the X△ building at time 10.

[0055] The database 12 stores the ID information of the position RFID tag 30, the ID information of the item RFID tag 40, the relative position of the item RFID tag 40 with respect to the position RFID tag 30, the detection time of the item RFID tag 40, and the detection time of the position RFID tag 30 in a linked manner.

[0056] By using the installation time of the position RFID tag 30 in the database 11 and the installation time of the position RFID tag 30 in the database 12, data processing suitable for the case where the position RFID tag 30 is moved becomes possible as described in FIG. 12. The RFID reader and the server 20 can communicate with each other via any network such as the Internet or an intranet. The server 20 as an information processing device may be composed of one device or multiple devices. The server 20 may also be composed of multiple devices linked together via a network such as a cloud. The server 20 and the information terminal 10 may also be integrated.

[0057] Fig. 10 is a flowchart showing the processing executed in the RFID reader 100 of this embodiment. Each step of the flowchart in Fig. 10 is realized by the calculation unit 101 of the RFID reader 100 executing a program stored in the storage unit 102.

[0058] In S221, the RFID reader 100 transmits to the server 20 information linking the RFID reader ID information, the RFID tag ID information, the detection time of the RFID tag, and the relative position of the RFID tag with respect to a reference position.

[0059] The RFID reader 100 in this embodiment performs only the minimum necessary data processing, transmits the data to the server 20, and the server 20 processes the data necessary for position detection. In this way, in the system 2 of this embodiment, the RFID reader 100 requires less data processing, so that the calculation unit 101 can have a lower calculation capacity, and the data capacity required for the memory unit 102 can be reduced.

[0060] Fig. 11 is a flowchart showing processing executed in the server 20 of this embodiment. Each step of the flowchart in Fig. 11 is realized by the control unit 1802 of the server 20 executing a program stored in the storage unit 1801.

[0061] In S201, the server 20 waits until data arrives from the RFID reader 100, and proceeds to S202. In S202, the server 20 determines whether the RFID reader 100 has been restarted by turning the power on and off. If the RFID reader 100 has been restarted, the reference position at the time of restart, which serves as the reference, has changed, and therefore it is no longer possible to detect information on the relative position between the detection result of the RFID tag before the restart and the detection result of the RFID tag after the restart. Therefore, if the RFID reader 100 has been restarted, the process proceeds to S208 to S210, and data processing of the RFID tag detected before the restart is completed. Then, the data for which the analysis of the database 21 has been completed is deleted, and the process returns to S201. By deleting old data after the data analysis is completed in this way, the databases 21a and 21b can reduce the data capacity required to be stored in the server 20.

[0062] In this embodiment, a case will be described in which the RFID readers 100a and 100b are restarted between time 12 and time 20 and between time 21 and time 31 shown in Fig. 9. For the sake of explanation, old data to be deleted is also displayed in the databases 21a and 21b in Fig. 9.

[0063] In S203, the server 20 receives data linking the ID information of the RFID reader, the ID information of the RFID tag, the detection time of the RFID tag, and the relative position of the RFID tag with respect to the reference position. In S204, the server 20 determines whether the RFID tag is a position RFID tag 30 or an article RFID tag 40 based on the ID information of the RFID tag. If it is a position RFID tag 30, the process proceeds to S205, and if it is an article RFID tag 40, the process proceeds to S206.

[0064] In S205, the server 20 stores the data received in S203 in the database 21a as data of the position RFID tag 30. In S206, the server 20 stores the data received in S203 in the database 21b as data of the article RFID tag 40. In S207, the server 20 confirms that there is a request to analyze the data in the databases 21a and 21b. The data analysis by the server 20 is performed, for example, when a predetermined amount of data or more has accumulated in the databases 21a and 21b, at regular intervals, or in response to an instruction from a user.

[0065] In S208, the server 20 associates the position RFID tag 30 and the article RFID tag 40 detected at the nearest time from the databases 21a and 21b among the data detected by the same RFID reader 100. Then, the process proceeds to S208.

[0066] As a modified example of the data linking method of the databases 21a and 21b, a method of linking and storing the position RFID tag 30 and the article RFID tag 40 detected at the closest relative position by the same RFID reader 100 may be used. Furthermore, if the storage capacity of the database 12 is large, the number of combinations of data for linking the position RFID tag 30 and the article RFID tag 40 may be increased. For example, a method of linking the article RFID tag 40 with both the position RFID tag 30 detected at the closest time and the position RFID tag 30 detected at the closest relative position and storing them in the database 12 may be considered.

[0067] The linked data 120 shown in parentheses in the database 12 shown in FIG. 9 is an example in which data other than the position RFID tag 30 and the article RFID tag 40 detected at the most recent time are linked together.

[0068] In S209, the server 20 calculates the relative position of the article RFID tag 40 with respect to the position RFID tag 30, which was linked in the processing of S208, based on the relative position of the position RFID tag 30 with respect to the reference position and the relative position of the article RFID tag 40 with respect to the reference position.

[0069] In this way, the data transmitted from the RFID reader 100 to the server 20 is linked to information on the relative positions of the article RFID tag 40 and the position RFID tag 30 based on a common reference position (in this embodiment, the initial position when the RFID reader 100 is started up). Therefore, the relative position of the article RFID tag 40 with respect to the position RFID tag 30 can be calculated by data processing by the server 20.

[0070] Furthermore, the common reference position does not have to be the initial position at which the RFID reader 100 was started, and for example, the position at which the RFID reader 100 first detects an RFID tag after starting may be the reference position. The method described in Fig. 11 is one example of a means for transmitting information on the relative positions of multiple RFID tags detected by the RFID reader 100 to the server 20, and other methods may also be used.

[0071] The RFID reader 100 is characterized by having at least a means for detecting the ID information of the RFID tag and detecting information on the relative position of the RFID tag with respect to a reference position. The server 20 can calculate the relative position of the position RFID tag 30 with respect to the article RFID tag 40 based on the ID information and relative position information of the multiple RFID tags transmitted from the RFID reader 100.

[0072] In S210, the server 20 associates the ID information of the article RFID tag 40, the ID information of the position RFID tag 30, the detection time of the article RFID tag 40, the detection time of the position RFID tag 30, and the relative position of the article RFID tag 40 with respect to the position RFID tag 30. Then, the server 20 stores the information in the database 12.

[0073] The above process is repeated until a system shutdown request is received (S114).

[0074] 12 is an example of a display displayed on the display unit 14 of the information terminal 10 in this embodiment. The display example shown in Fig. 12 displays location information of items to be managed based on information from the databases 11 and 12.

[0075] Based on user instructions via an interface (not shown) of the information terminal 10, the information terminal 10 transmits information such as a location name, an item name, and a time to the server 20. The server 20, which has received this information, selects data required for display on the display unit 14 from the database 12 and transmits it to the information terminal 10. The information terminal 10 displays the location information of the item on the display unit 14 based on the data received from the server 20.

[0076] FIG. 12(A) shows an example of display of the position information of the article RFID tag 40 based on the 1st floor north of the X△ building (ID information 30a of the position RFID tag 30) at time 11. From the database 11 in FIG. 9, it can be seen that the position RFID tag 30 was installed on the 1st floor north of the X△ building from time 10 to time 20. The server 20 selects data in which the ID information of the position RFID tag 30 matches 30a, the detection time is in the period from time 10 to time 20, and the detection time of the article RFID tag is closest to time 11. The server 20 transmits the article name of the article RFID tag 40 of the selected data and the information of the relative position of the article RFID tag 40 with respect to the position RFID tag 30a in association with each other, so that the information terminal 10 can display the position information of the article shown in FIG. 12(A) on the display unit 14.

[0077] In the data processing of the server 20, the information of the items a and b is linked to the 1st floor north of the X△ building based on the detection result of the RFID reader 100a. The information of the item c is linked to the 1st floor north of the X△ building based on the detection result of the RFID reader 100b. In this way, by integrating the information detected by the multiple RFID readers 100 in the server 20, it is possible to reduce the number of missed detections of the item RFID tags 40.

[0078] Fig. 12(B) shows the position information of the article RFID tag 40 based on the 2nd floor of the X△ building (ID information 30a of the position RFID tag 30) at time 21. It can be seen from the database 11 in Fig. 9 that the position RFID tag 30 with the ID information 30a was installed on the 2nd floor of the X△ building at time 20. Therefore, the display in Fig. 12(B) uses the detection results of the position RFID tag 30 and the article RFID tag 40 detected after time 20.

[0079] As described here, the only work required by the user when moving the position RFID tag 30 is to register the name of the new location and the installation time in the database 11 after moving the position RFID tag 30. Therefore, the user can move the location where the position detection system 2 is used with a simple operation.

[0080] Furthermore, the database 12 stores the detection time of the position RFID tag 30 in addition to the detection time of the article RFID tag 40. Therefore, even if the user installs the position RFID tag 30 in a new location and then registers the name of the new location of the position RFID tag 30 and the installation time in the database 11 after a while, it becomes possible to display the position information of the article by going back to the past data in the database 12. When the position RFID tag 30 is moved, it is effective to store the detection time of the position RFID tag 30 in the database 12 as well.

[0081] Fig. 12(C) shows the position information of the article RFID tag 40 based on the east 1st floor of the X△ building (ID information 30b of the position RFID tag 30) at time 31. As shown in the database 11 in Fig. 9, the position RFID tag 30 with the ID information 30b was installed on the east 1st floor of the X△ building at time 10. Therefore, the display in Fig. 12(C) uses the detection results of the position RFID tag 30 and the article RFID tag 40 detected after time 10 from among the data of the article RFID tag 40 linked to the position RFID tag 30 with the ID information 30b.

[0082] Here, the effect of the control method of this embodiment will be described for the case where user A of the RFID reader 100a installs the position RFID tag 30a and user B of the RFID reader 100b installs the position RFID tag 30b. At time 31, user B installed the position RFID tag 30b on the east side of the 1st floor of the XX building, so even at time 31, user A was able to detect the relative positions of the position RFID tag 30b and the items b and c with the RFID reader 100a. In this way, it can be seen that the more users use the position detection system 2 and install position RFID tags 30, the easier it becomes to detect the position of the item RFID tag 40.

[0083] As a modified example of the position detection system 2, the information terminal 10 is not used, and instead the display unit 14 may be provided in the RFID reader 100, and the server 20 may transmit data to the RFID reader 100 and display the data on the display unit 14 of the RFID reader 100. Also, instead of the RFID reader 100 and the server 20 directly communicating with each other, the RFID reader 100 and the information terminal 10 may be connected to each other, and the RFID reader 100 and the server 20 may communicate with each other via the information terminal 10. Also, the server 20 may not be used, and instead the information terminal 10 may process the data of the server 20 of this embodiment.

[0084] As described above, the RFID reader 100 of this embodiment is characterized in that it has a means for detecting the ID information of an RFID tag and detecting information on the relative position of the RFID tag with respect to a reference position. Then, the server 20 can calculate the relative positions of the article RFID tag and the location RFID tag based on the information transmitted from the RFID reader 100.

[0085] [Third embodiment] 13 is a system diagram of the third embodiment. The system of this embodiment uses an RFID reader 200 that is an integrated combination of the RFID reader 100 of the first embodiment and an information terminal 10. The system differs from the first embodiment in that only the ID information of the article RFID tag 40 and the information of the relative position from the reference position are linked and stored in the database 12. Note that the same reference numerals are used for the same configuration as the first embodiment, and the description thereof will be omitted.

[0086] 13, an RFID reader 200 is obtained by adding the functions of a display unit 14 and a database 11 and a database 12 to the RFID reader 100 in the first embodiment. Alternatively, the communication unit 103 may be omitted.

[0087] Furthermore, the system 3 of this embodiment is a system with only one position RFID tag 30, and there is no need to link and store the ID information of the position RFID tag 30 with the ID information of the article RFID tag 40 and information on the relative position in the database 12. There is also no need to link and store the position RFID tag 30 in the database 11 with the position name. To distinguish between the position RFID tag 30 and the article RFID tag 40, only the ID information of the position RFID tag 30 is stored in the database 11.

[0088] In addition, this system can display only the latest detection result of the position information on the display unit 14, and there is no need to link the detection time of the item RFID tag 40 and store it in the database 12. For each ID, the latest detection result of the item RFID tag 40 is updated and stored.

[0089] Fig. 14 is a flowchart showing the processing executed by the RFID reader 200 of this embodiment. This flowchart differs from the flowchart of the first embodiment described in Fig. 4 in that after the position RFID tag is detected in S105, updating of the data of the article RFID tag is started. Also, it differs in that only the ID information of the article RFID tag 40 and information on the relative position of the article RFID tag 40 with respect to the position RFID tag 30 are saved in S314. Each step of the flowchart in Fig. 14 is executed by the calculation unit 101 of the RFID reader 200, similar to the description in Fig. 4.

[0090] In the control of this embodiment, the RFID reader 200 does not update the data of the RFID tag until it detects the position RFID tag 30 in S105. Therefore, in S301, until the position RFID tag 30 is detected for the first time, a display is displayed on the display unit 14 to prompt the user to approach the position RFID tag.

[0091] Furthermore, when the RFID reader 100 fails to detect the position RFID tag 30 for a predetermined period of time after starting control, the display unit 14 can be used to display an image or sound a buzzer, thereby urging the user to detect the position RFID tag 30. This can be implemented in the first and second embodiments in the same way.

[0092] In S314, the RFID reader 200 updates the database 12 with respect to the ID information of the article RFID tag 40 and the information of the relative position of the article RFID tag 40 with respect to the position RFID tag 30a, and displays on the display unit 14 the relative position of the article RFID tag with respect to the position RFID tag 30a.

[0093] The above process is repeated until a system shutdown request is received (S114).

[0094] As described above, in the position management system 3 of this embodiment, since it is not necessary to store the ID information of the position RFID tag 30 and the detection time of the article RFID tag 40, the data capacity required for the database 12 can be further reduced. Therefore, the system is applicable even when the data capacity of the memory unit 102 of the RFID reader 200 is small. In addition, since it is not necessary to communicate with the information terminal 10 or the server 20, the communication unit 103 is not required, and the cost of the RFID reader 200 can be reduced.

[0095] The data managed by the database 12 in this embodiment are only the ID information of the article RFID tag 40 and information on the relative position of the article RFID tag 40 with respect to the position RFID tag 30. Even in such a case, it is possible to manage the position information of managed objects having RFID tags attached thereto that can be installed inexpensively and easily both indoors and outdoors and that are located over a wide range.

[0096] [Explanation of location RFID tags and item RFID tags] As an example of the position RFID tag 30 and the article RFID tag 40 that can be used in the first to third embodiments, an explanatory diagram of an RFID tag is shown in FIG.

[0097] 15(A) is used as a reference position for managing the position information of an article to which an article RFID tag 40 is attached. A holding member 32 is an exterior used to hold the position RFID tag 30.

[0098] As shown in FIG. 15(B), an article RFID tag 40 is an RFID tag attached to an article.

[0099] Incidentally, the position RFID tag 30 and the article RFID tag 40 are RFID tags that can communicate with the RF control unit 110 of the RFID reader 100 and operate on the same principle. Therefore, in the method of managing position information described in the first to third embodiments, it is not necessary to provide separate detection circuits for detecting the article and the position, and this provides advantages such as reduced cost and size of the RFID reader 100 and low power consumption.

[0100] [Methods for improving the accuracy of detecting the location of objects] The control flowcharts of Figures 6 and 7 show a method for further improving the accuracy of the position information of the article RFID tag 40. These processes may be executed appropriately when the RFID reader detects the position RFID tag in each of the first to third embodiments. Each step of the flowcharts of Figures 6 and 7 is realized by the calculation unit of the RFID reader executing a program stored in the memory unit.

[0101] The control of FIG. 6 begins when the RFID reader 100 detects the location RFID tag 30 .

[0102] In S401, the RFID reader 100 stores the ID information of the detected position RFID tag 30 in the memory unit 102. In S402, the RFID reader 100 weakens the level of the RF output (Tx signal) of the RF control unit 110 of the RFID reader 100. In S403, the RFID reader 100 determines whether it has been possible to communicate again with the position RFID tag 30 stored in S401. If communication has been possible, the process proceeds to S402, where the RF output of the RFID reader is further weakened, and the process is repeated in S403 until communication is no longer possible. If communication has not been possible, the process proceeds to S404.

[0103] In S404, the RFID reader 100 associates the lowest RF output that successfully communicated with the position RFID tag 30 with the ID information of the position RFID tag 30 and stores it. In S405, the RFID reader 100 determines whether the RF output value is the lowest within a predetermined period of time among the history of successful communication with the position RFID tag 30 of the same ID information. If it is the lowest RF output value in S405, the process proceeds to S108, where the ID information of the detected position RFID tag 30 is stored in the memory unit 102, and the process proceeds to S112, where the relative position is set to 0. If it is not the weakest RF output value in S405, the detection result of the position RFID tag is invalidated, and the relative position is not set to 0.

[0104] 6, when the RFID reader 100 detects the position RFID tag 30 with a weak RF output, it determines that the position RFID tag 30 and the RFID reader 100 are in close positions. Then, by setting the relative position to 0 at that timing, the data of the position RFID tag 30 detected with a weak RF output and the detection data of the article RFID tag 30 are linked together.

[0105] The control in FIG. 7 is also started when the RFID reader 100 detects the positional RFID tag 30 .

[0106] In S504, the RFID reader 100 stores the strength of the RF input (Rx signal) received by the RF control 110 of the RFID reader 100 in the memory unit 102. In S505, the RFID reader 100 determines whether the RF input value is the strongest within a predetermined period of time among the history of successful communication with the position RFID tag 30 of the same ID information. If it is the strongest RF input value in S505, the process proceeds to S108, where the ID information of the detected position RFID tag 30 is stored in the memory unit 102, and the process proceeds to S112, where the relative position is set to 0. If it is not the strongest RF input value in S505, the detection result of the position RFID tag is invalidated, and the relative position is not set to 0.

[0107] 7, when the RFID reader 100 detects the position RFID tag 30 with a strong RF input, it determines that the position RFID tag 30 and the RFID reader 100 are in close positions. Then, by resetting the relative position at that timing, the system is characterized in that the data of the position RFID tag 30 detected with a strong RF input and the detection data of the article RFID tag 40 are linked.

[0108] In the article position management system according to each embodiment of the present invention, the position RFID tag 30 is set as the reference position. Therefore, by implementing the control method described in Fig. 6 and Fig. 7 on the position RFID tag 30 in particular, it is possible to further improve the accuracy of the managed position information.

[0109] Moreover, by carrying out control similar to that shown in FIG. 6 or FIG. 7 with respect to the article RFID tag 40, the accuracy of the managed position information can be further improved.

[0110] Furthermore, when data processing is performed by the server 20 as in the second embodiment, data on the strength of the RF input and the strength of the RF output of the RFID reader 100 are stored in association with the databases 21a and 21b of the server 20. This allows the server 20 to perform the same control as in Figures 6 and 7. The method for improving the accuracy of location information described in Figures 6 and 7 can also be applied to the second embodiment.

[0111] 8 shows a method for utilizing a charging device 300 as a position RFID tag 30 by incorporating the function of the position RFID tag 30 in a charging device 300 of an RFID reader 100. Reference numeral 301 denotes a connector used for connecting the RFID reader 100 and the charging device 300.

[0112] By using this charging device 300, the position RFID tag 30 can be detected at close range when charging the RFID reader 100. In particular, by combining with the controls of Figs. 6 and 7, the accuracy of the position information of the RFID reader 100 can be improved.

[0113] [Control of antenna radiation directivity] Antenna unit 115 having a radiation directivity control function that can be used in the first to third embodiments is shown in Fig. 16. Substrate 1101 and substrate 1102 are arranged overlapping in the -Z direction, in that order, along the Z axis which is the thickness direction of the substrates.

[0114] Fig. 16(a) shows the surface of substrate 1101. The four antenna elements 1103 are arranged with their extension directions changed by 90 degrees along the X-axis and Y-axis so that the open ends do not overlap, and the feed end, which is the end opposite the open end, is connected to via 1104. Note that the extension direction of the open ends may be reversed, and the element shape may be folded into a meandering shape.

[0115] 16(b) shows the back surface of the substrate 1101. Four vias 1104 each penetrate the substrate 1101 and connect to four pads 1105.

[0116] 16(c) shows the surface of the substrate 1102. Four pads 1106 are respectively connected to a ground 1107 and four RF lines 1108. Here, pads 1105 and 1106 are electrically connected by being in surface contact with a metal spacer that is a conductive portion (not shown).

[0117] Each of the four RF lines 1108 passes through four RF switches 1109 (1109a to d), passes through a common RF line 1110, and is connected to a transmitting / receiving unit 1111 (coupler 114).

[0118] RF switch 1109 connects one end to RF line 1108 and the other end to RF line 1110, and controls whether it is short-circuited or open. Therefore, when RF switch 1109 is in a short-circuited state, an RF signal can pass between transceiver unit 1111 and antenna element 1103, and when it is in an open state, an RF signal cannot pass between transceiver unit 1111 and antenna element 1103.

[0119] 16(d) shows the back surface of the substrate 1102. The ground 1112 is arranged on the entire surface, avoiding the area overlapping with the pad 1106, and is electrically connected to the ground 1107 by a plurality of vias (not shown) that penetrate the substrate 1102. Here, the line width and line thickness of the RF line 1108 and the RF line 1110 are determined from the layer structure and dielectric constant of the substrate 1102 so that they are approximately 50 ohms at the frequency of the RF signal.

[0120] The four pads 1106 are designated A, B, C, and D in a counterclockwise direction from the upper right in the figure, and the total electrical lengths of the RF lines connecting A, B, C, and D to the transceiver unit 1111 are defined as a, b, c, and d. In this case, the four RF lines 1108 satisfy the relationships b=a+λ / 4, c=b+λ / 4, and d=c+λ / 4, and are arranged in a meandering pattern so as not to overlap with the ground 1107. Note that the phase difference between the four RF lines 1108 needs to be λ / 4, that is, approximately 90 degrees each, and the rotation direction and mounting method for providing the phase difference do not matter, and a phase shifter may be used instead of the line length.

[0121] The RF signal transmitted and received by the antenna section 115 becomes a circularly polarized wave when it is a composite wave of four antenna elements 1103, and becomes a linearly polarized wave when it is a composite wave of any combination of two opposing antenna elements 1103.

[0122] In this embodiment, the radiation characteristics of the antenna resonating at 920 MHz are shown in Fig. 17. In this case, substrates 1101 and 1102 have a substrate thickness of 1 mm and a relative dielectric constant of 4.3, the distance between substrates 1101 and 1102 is 7 mm, and the element length of the inverted-F antenna is approximately λ / 4. The line width of the RF line is 1.6 mm, and the line thickness is 35 um.

[0123] FIG. 17(a) shows the radiation characteristics when all of the RF switches 1109a to 1109d are short-circuited, and a circularly polarized RF signal having the main directivity in the +Z direction is radiated.

[0124] FIG. 17(b) shows the radiation characteristics when RF switches 1109a and 1109c are shorted and RF switches 1109b and 1109d are open, and linearly polarized RF signals are radiated in the +X and -X directions.

[0125] FIG. 17(c) shows the radiation characteristics when RF switches 1109b and 1109d are shorted and RF switches 1109a and 1109c are open, and linearly polarized RF signals are radiated in the +Y and -Y directions.

[0126] As described above, by switching the directivity, it becomes possible to read RFID tags placed in the X and Y axis directions that cannot be read by only the circularly polarized RF signal radiated in the +Z direction. This makes it possible to detect the position information of items with RFID tags attached over a wider range. The RFID reader 100 is characterized in that it detects RFID tags while switching the radiation characteristics of the antenna unit 115 in multiple directions, and the antenna unit 115 is suitable for use in the first to third embodiments.

[0127] [Other embodiments] The first to third embodiments described above can be implemented in appropriate combination. For example, the RFID reader having the display unit shown in the third embodiment does not necessarily need to display the managed item location information on the display unit of the device itself, and may transmit the information to a server or an information terminal. Alternatively, the user may be able to select appropriately whether to display the information on the RFID reader or to transmit the information to the server or the information terminal.

[0128] The present invention can also be realized by a process in which a program for implementing one or more of the functions of the above-described embodiments is supplied to a system or device via a network or a storage medium, and one or more processors in a computer of the system or device read and execute the program. The present invention can also be realized by a circuit (e.g., ASIC) that implements one or more of the functions. [Explanation of symbols]

[0129] 100, 200 RFID Reader 10 Information terminals 20 Servers 30(30a~30c) Location RFID Tag 40(40a~40f) RFID tag for items 115 Antenna 300 Charging device

Claims

1. 1. A communication device, comprising: Power supply, A detection means for detecting a wireless device; a storage means for storing identification information of the wireless device; a calculation means for calculating a first relative position of a second wireless device different from a first wireless device serving as a reference for identifying a position based on an amount of movement of the communication device; an association means for associating the first relative position, identification information of the second wireless device, and identification information of the first wireless device; having When the position of the communication device at the time of starting up the power supply of the communication device is set as an initial position, When the second wireless device is detected in a state where the first wireless device is not detected after the detection means detects the initial position, the storage means stores a second relative position of the second wireless device with respect to the initial position, and when the detection means detects the first wireless device after detecting the second wireless device, stores a third relative position of the first wireless device with respect to the initial position; The communication device, wherein the calculation means calculates the first relative position based on the second relative position and the third relative position, which indicate the amount of movement of the communication device.

2. a determination unit for determining whether the wireless device detected by the detection unit is the first wireless device, The communication device according to claim 1, characterized in that when the detected wireless device is determined to be the first wireless device by the judgment means, the storage means stores identification information of the detected wireless device as identification information of the first wireless device.

3. 3. The communication apparatus according to claim 1, wherein the associating means further associates information indicating a time when the wireless device was detected.

4. 4. The communication device according to claim 1, further comprising a transmitting unit for transmitting the information associated by the associating unit to an information terminal.

5. 5. The communication device according to claim 1, further comprising a display unit that displays position information of the second wireless device based on the calculated first relative position.

6. 6. The communication device according to claim 1, wherein the communication device is an RFID reader, the wireless device is an RFID tag, and the detection means detects the wireless device using an RFID.

7. 7. The communication apparatus according to claim 1, wherein the detection unit detects the wireless device by using an antenna capable of switching a radiation directivity of radio waves.

8. a receiving means for receiving, from a communication device that has detected a wireless device, identification information of the detected first wireless device and information on a first relative position of the first wireless device with respect to an initial position; a calculation means for calculating a third relative position of the second wireless device from the first wireless device based on information on the first relative position received by the receiving means and information on a second relative position from the initial position of a second wireless device serving as a reference for identifying a position different from that of the first wireless device; an association unit that associates the third relative position calculated by the calculation unit with identification information of the first wireless device and identification information of the second wireless device; having If the position of the communication device when the power supply of the communication device is turned on is the initial position, When the first wireless device is detected in a state in which the second wireless device is not detected after the initial position is detected, The calculation means is An information processing device characterized by calculating the third relative position based on the first relative position and a second relative position of the second wireless device with respect to the initial position when the second wireless device is detected after the first wireless device is detected.

9. The information processing device according to claim 8, characterized in that the receiving means receives information indicating the time when the communication device detected a wireless device, and the calculation means selects a wireless device for calculating the third relative position based on a first time when the first wireless device was detected and a second time when the second wireless device was detected.

10. 10. The information processing apparatus according to claim 8, further comprising a transmitting means for transmitting information on the third relative position calculated by the calculating means to an information terminal.

11. 11. The information processing device according to claim 8, further comprising a display means for displaying position information of a wireless device indicated by identification information received by the receiving means, based on the third relative position calculated by the calculating means.

12. An information processing device according to any one of claims 8 to 11, characterized in that the wireless device is an RFID tag, the communication device that detects the wireless device is an RFID reader, and the receiving means receives information about the wireless device detected by the communication device using RFID.

13. A program for causing a computer to operate as the communication device according to any one of claims 1 to 7.

14. A program for causing a computer to operate as the information processing device according to any one of claims 8 to 12.

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