Wireless tag reading apparatus, wireless tag reading method, and program storage medium

Abstract

A wireless tag reading apparatus, a wireless tag reading method, and a program storage medium are disclosed. The wireless tag reading apparatus includes a plurality of wireless tag communication antennas, a number acquisition unit, a strength acquisition unit, and a direction designation unit. Each of the antennas is disposed along a passage through which a wireless tag passes. The number acquisition unit acquires, for each of the antennas, a number of times data of the wireless tag is read by each of the antennas in each unit time. The strength acquisition unit acquires, for each of the antennas, a received signal strength when the data of the wireless tag is read by each of the antennas in each unit time. The direction designation unit designates a moving direction of the wireless tag passing through the passage based on the number of times and the received signal strength acquired for each of the antennas in each unit time.

Description

TECHNICAL FIELD

[0001] An embodiment of the present application relates to a wireless tag reading apparatus, a wireless tag reading method, and a program storage medium. BACKGROUND

[0002] A technique of specifying a moving direction of a wireless tag coming and going along a passage by configuring a plurality of antennas for wireless tag communication along the passage and specifying the moving direction of the wireless tag based on a time of communication with the wireless tag through each antenna or a number of times of reading data of the wireless tag is known.

[0003] PRIOR ART DOCUMENTS

[0004] Patent Document 1: Japanese Patent Laid-Open No. 2009-265993

[0005] Patent Document 2: Japanese Patent Laid-Open No. 2009-007157

[0006] Patent Document 3: Japanese Patent Laid-Open No. 2010-082454 SUMMARY

[0007] An embodiment of the present application relates to a wireless tag reading apparatus, a wireless tag reading method, and a program storage medium.

[0008] The wireless tag reading apparatus according to an embodiment of the present application includes: a plurality of antennas configured along a passage where a wireless tag comes and goes, for wireless tag communication; a number-of-times acquisition section that acquires, for each unit time, a number of times of reading data of the wireless tag through the plurality of antennas respectively; a strength acquisition section that acquires, for each unit time, a received signal strength at the time of reading data of the wireless tag through the plurality of antennas respectively, for each antenna; and a direction specifying section that specifies a moving direction of the wireless tag coming and going along the passage based on the number of times and the received signal strength acquired for each antenna for each unit time.

[0009] The wireless tag reading method according to an embodiment of the present application is used in a wireless tag reading apparatus in which a plurality of antennas for wireless tag communication are configured along a passage where a wireless tag comes and goes, and includes: acquiring, for each unit time, a number of times of reading data of the wireless tag through the plurality of antennas respectively, for each antenna; acquiring, for each unit time, a received signal strength at the time of reading data of the wireless tag through the plurality of antennas respectively, for each antenna; and specifying a moving direction of the wireless tag coming and going along the passage based on the number of times and the received signal strength acquired for each antenna for each unit time.

[0010] The program storage medium of the embodiment of the present application stores a control program that causes a computer of a wireless tag reading device configured with a plurality of wireless tag communication antennas along a passage where a wireless tag comes and goes to execute each function including: acquiring, for each antenna, a number of times of reading data of the wireless tag read by the plurality of antennas respectively, in each unit time; acquiring, for each antenna, a received signal strength at the time of reading data of the wireless tag by the plurality of antennas respectively, in each unit time; and specifying a moving direction of the wireless tag to and from the passage, based on the number of times of reading and the received signal strength acquired for each antenna in each unit time. BRIEF DESCRIPTION OF DRAWINGS

[0011] Figure 1 is a schematic diagram for explaining a wireless tag reading device involved in an embodiment.

[0012] Figure 2 is a schematic diagram showing a main data structure of a tag record held by a tag database.

[0013] Figure 3 is a block diagram showing a main circuit configuration of a movement monitoring device.

[0014] Figure 4 is a configuration diagram of a work buffer formed in a main memory of a movement monitoring device.

[0015] Figure 5 is a configuration diagram of a conversion list, a log file, and a determination file formed in an auxiliary storage device of a movement monitoring device.

[0016] Figure 6 is a flowchart showing a main information processing sequence executed by a processor in accordance with a control program.

[0017] Figure 7 is a flowchart showing a specific sequence of a log creation processing in Figure 6

[0018] Figure 8 is a flowchart showing a specific sequence of a determination processing in Figure 7

[0019] Figure 9 is a flowchart showing a specific sequence of a region specifying processing in Figure 6

[0020] Figure 10 is a diagram showing an example of an image displayed by a display device of a movement monitoring device. DETAILED DESCRIPTION

[0021] ​​​In one embodiment, a wireless tag reading device includes a plurality of antennas for wireless tag communication, a number acquisition section, a strength acquisition section, and a direction designation section. Each antenna is disposed along a passage for a wireless tag to pass. The number acquisition section acquires, for each antenna, a number of times data of the wireless tag is read by each of the plurality of antennas in each unit time. The strength acquisition section acquires, for each antenna, a received signal strength when the data of the wireless tag is read by each of the plurality of antennas in each unit time. The direction designation section designates a moving direction of the wireless tag passing through the passage based on the number of times and the received signal strength acquired for each antenna in each unit time.

[0022] An embodiment will be described below with reference to the drawings.

[0023] Figure 1 is a schematic view for explaining a wireless tag reading device 1 according to one embodiment. The wireless tag reading device 1 has a function of designating a moving direction of a wireless tag 2 passing through a passage 300 connecting a first area 100 and a second area 200. In addition, the wireless tag reading device 1 has a function of designating an existence area of the wireless tag 2, that is, designating whether the wireless tag 2 exists in the first area 100 or the second area 200, based on information related to the moving direction of the wireless tag 2.

[0024] In one embodiment, the wireless tag 2 is attached to a commodity 3. The commodity 3 can be a single commodity or a case in which a plurality of commodities are housed. The commodity 3 in the first area 100 sometimes moves in a direction indicated by an arrow Da shown in FIG. 1 through the passage 300 and moves to the second area 200. The commodity 3 in the second area 200 sometimes moves in a direction indicated by an arrow Db shown in FIG. 1 through the passage 300 and moves to the first area 100. Figure 1 Figure 1

[0025] For example, the first area 100 is a warehouse of a store and the second area 200 is a sales floor of the store. In such a store, at the time of shipment, the commodity 3 stored in the warehouse is transferred to the sales floor through the passage 300. The commodity 3 that is recycled in the sales floor due to expiration or the like is transferred to the warehouse through the passage. The wireless tag reading device 1 is able to acquire information on which direction the moving wireless tag 2 moves through the passage 300, that is, whether the commodity 3 is transferred from the warehouse to the sales floor or from the sales floor to the warehouse, by communicating with the wireless tag 2 attached to the commodity 3.

[0026] The wireless tag reading device 1 having the above-described function includes two readers / writers (R / W) 10, 20, two antennas 11, 21 connected to the respective readers / writers 10, 20, and a movement monitoring device 30.

[0027] ​​Each of the antennas 11, 21 is an antenna for reading a wireless tag. For example, a planar antenna of a circularly polarized wave or a linearly polarized wave is used as the antennas 11, 21. Each of the antennas 11, 21 is disposed along the passage 300. In Figure 1 one of the antennas 11 is disposed on the first region 100 side, and the other of the antennas 21 is disposed on the second region 200 side. Thereafter, the orientation, the height from the ground, the electric wave output level, the Q value, and the like of the antennas 11, 21 are set in a manner that the wireless tag readable region 110 viewed from the top surface of the one of the antennas 11 and the wireless tag readable region 210 viewed from the top surface of the other of the antennas 21 cover the entire width of the passage 300.

[0028] The readers / writers 10, 20 read data stored in the memory of the wireless tag 2 that performs wireless communication via the corresponding antenna 11, 21. At least a tag ID is stored in the memory of the wireless tag 2. The tag ID is tag identification information uniquely set for each of the wireless tags 2, and is also called an RFID (Radio Frequency Identification) or the like.

[0029] The readers / writers 10, 20 include RSSI measuring sections 12, 22 for measuring a received signal strength indicator (RSSI). The RSSI measuring sections 12, 22 measure the electric field strength of an electric wave signal received with the corresponding antenna 11, 21. That is, the RSSI measuring sections 12, 22 measure the electric field strength at the time when an electric wave signal transmitted from the wireless tag 2 that has received a reading electric wave emitted from the antenna 11, 21 is received with the same antenna 11, 21 as the RSSI. The readers / writers 10, 20 output the RSSI at the reading time point together with the tag ID to the movement monitoring device 30 each time the tag ID is read from the wireless tag 2.

[0030] The movement monitoring device 30 is a computer device for monitoring the movement of the wireless tag 2 to and from the passage 300 on the basis of the tag ID and the RSSI of the wireless tag 2 read out by the readers / writers 10, 20. The movement monitoring device 30 is connected to the commodity management device 40.

[0031] The commodity management device 40 is a computer device for managing the presence region of a commodity attached with the wireless tag 2. The commodity management device 40 has a tag database (DB) 41. The tag database 41 is a collection of tag records 410 (refer to Figure 2 ).

[0032] As Figure 2As shown, the tag record 410 includes items of a tag ID, a product code, a product name, a region name, a date and time, and the like. The product code and the product name are inherent codes and names of the product 3 to which the wireless tag 2 storing the tag ID as identification information is attached. The region name is a name indicating a region in which the product 3 exists. For example, in a case where the first region 100 is a warehouse and the second region 200 is a store, the region name of the tag record 410 of the product 3 existing in the warehouse is "warehouse". The region name of the tag record 410 of the product 3 existing in the store is "store". The date and time is a date and time at which the product 3 moves to the region of the region name. The region name and the date and time are appropriately updated in accordance with movement information of the wireless tag 2 monitored by the movement monitoring device 30.

[0033] Figure 3 is a block diagram showing a main circuit configuration of the movement monitoring device 30. The movement monitoring device 30 includes a processor 31, a main memory 32, a secondary storage device 33, a clock 34, a communication interface (I / F) 35, a display device 36, an input device 37, and two device interfaces 38 and 39. The processor 31 of the movement monitoring device 30 is connected to the main memory 32, the secondary storage device 33, the clock 34, the communication interface 35, the display device 36, the input device 37, and the two device interfaces 38 and 39 through a system bus 310. The system bus 310 includes an address bus, a data bus, and the like. The movement monitoring device 30 is configured as a computer by the processor 31 being connected to the main memory 32, the secondary storage device 33, the clock 34, and the communication interface 35 through the system bus 310.

[0034] The processor 31 corresponds to a central part of the above-described computer. The processor 31 controls each part to realize various functions as the movement monitoring device 30 in accordance with an operating system or an application program. The processor 31 can also be a processing circuit such as a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), a programmable logic device (for example, an SPLD (Simple Programmable Logic Device), a CPLD (Complex Programmable Logic Device), or an FPGA (Field Programmable Gate Array)), or the like. The processor 31 is not limited to a case where the processor 31 is configured as a single processing circuit, and can be configured by combining a plurality of processing circuits.

[0035] The main memory 32 corresponds to a main storage portion of the above-described computer. The main memory 32 includes a nonvolatile memory area and a volatile memory area. The main memory 32 stores an operating system or an application program in the nonvolatile memory area. The main memory 32 stores data required in a process performed by the processor 31 for controlling a process of each section in the volatile memory area. In addition, the main memory 32 uses the volatile memory area as a work area in which data can be suitably rewritten by the processor 31. The nonvolatile memory area is, for example, a ROM (Read Only Memory). The volatile memory area is, for example, a RAM (Random Access Memory).

[0036] The auxiliary storage device 33 corresponds to an auxiliary storage portion of the above-described computer. As the auxiliary storage device 33, a publicly known storage device such as an EEPROM (Electric Erasable Programmable Read-Only Memory), an HDD (Hard Disc Drive), or an SSD (Solid State Drive) can be used alone or in combination of a plurality of them. The auxiliary storage device 33 stores data used in various processes performed by the processor 31, data generated in a process performed by the processor 31, and the like. The auxiliary storage device 33 sometimes also stores an application program.

[0037] The application program stored in the main memory 32 or the auxiliary storage device 33 includes a control program described later. A method of installing the control program in the main memory 32 or the auxiliary storage device 33 is not particularly limited. The control program can be stored in a removable storage medium or distributed by communication via a network and installed in the main memory 32 or the auxiliary storage device 33. The storage medium is not limited in form as long as it can store a program and is readable by the device, such as a CD-ROM, a memory card, and the like.

[0038] The clock 34 functions as a source of time information of the movement monitoring device 30. The processor 31 acquires a current date and time based on time information counted by the clock 34.

[0039] The communication interface 35 connects the commodity management device 40. The movement monitoring device 30 performs data communication between the communication interface 35 and the commodity management device 40.

[0040] The display device 36 is a device for displaying an image related to movement monitoring of the wireless tag 2. The display device 36 is, for example, a liquid crystal display. The input device 37 is a device for inputting data related to movement monitoring of the wireless tag 2. The input device 37 is, for example, a keyboard, a mouse, or the like. The movement monitoring device 30 can also be provided with a monitoring device having a touch panel function as a device serving as both the input device 37 and the display device 36.

[0041] The two device interfaces 38, 39 are connected to the reader / writer 10, 20, respectively. The mobile monitoring device 30 communicates with the reader / writer 10 via the device interface 38. The mobile monitoring device 30 acquires the tag ID and RSSI of the wireless tag 2 read by the reader / writer 10 via the device interface 38. In addition, the mobile monitoring device 30 communicates with the reader / writer 20 via the device interface 39. The mobile monitoring device 30 acquires the tag ID and RSSI of the wireless tag 2 read by the reader / writer 20 via the device interface 39.

[0042] As shown in Fig. 3, the mobile monitoring device 30 is configured to form a pair of work buffers 321, 322 in the volatile storage area of the main memory 32. Thereafter, the mobile monitoring device 30 sets "1" as the work buffer number (WB No.) for one work buffer 321 and sets "2" as the work buffer number for the other work buffer 322. Note that the number of work buffers 321, 322 is not limited to two. The mobile monitoring device 30 can include three or more work buffers, each of which is set with a consecutive number starting from "1" as the work buffer number. Figure 4

[0043] Each of the work buffers 321, 322 is an area for temporarily storing a data record composed of the tag ID, the antenna ID, the read count, and the RSSI total. Each of the work buffers 321, 322 can store a plurality of data records.

[0044] The antenna ID is a code set for each antenna in order to identify the antennas 11, 21, respectively. The antenna ID of the antenna 11 is set in the memory of the reader / writer 10. The reader / writer 10 appends the antenna ID of the antenna 11 to the tag ID of the wireless tag 2 read via the antenna 11 and outputs it to the mobile monitoring device 30. The antenna ID of the antenna 21 is set in the memory of the reader / writer 20. The reader / writer 20 appends the antenna ID of the antenna 21 to the tag ID of the wireless tag 2 read via the antenna 21 and outputs it to the mobile monitoring device 30.

[0045] The read count is the number of times the tag ID is read by the antenna 11, 21 corresponding to the antenna ID in a unit time. The RSSI total is the total of the RSSIs at the time of reading the tag ID corresponding to the read count.

[0046] As shown in Fig. 3, the mobile monitoring device 30 forms a part of the auxiliary storage device 33 as a conversion list 331, a log file 332, and a determination file 333. Figure 5

[0047] ​​The transformation list 331 is a data list in which a region name is set in association with each antenna ID of the antennas 11, 21, respectively. As described above, for the passage 300, the antenna 11 is disposed in the first region 100, and the antenna 21 is disposed in the second region 200. In addition, in the present embodiment, the first region 100 is a warehouse, and the second region is a sales floor. Therefore, the transformation list 331 sets the region name "warehouse" in association with the antenna ID (ANTa) of the antenna 11, and sets the region name "sales floor" in association with the antenna ID (ANTb) of the antenna 21.

[0048] The log file 332 is a region for recording data records composed of each item of time, tag ID, antenna ID, and state. The determination file 333 is a region for recording data records composed of each item of date and time, tag ID, and region name. Details of the data records recorded in the log file 332 and the determination file 333 will be clarified in the action explanation to be described later.

[0049] Figures 6 to 9 is a flowchart showing the main information processing order of the processor 31 in accordance with the control program. Hereinafter, using each figure, the main actions of the processor 31 will be explained. In addition, the order of the actions explained hereinafter is an example. The order can be changed as appropriate as long as the same effect can be obtained.

[0050] When the control program is started, as ACT 1, the processor 31 first resets the first counter T to "0". In addition, as ACT 2, the processor 31 resets the second counter N to "0". The first counter T and the second counter N are formed in, for example, a volatile region of the main memory 32.

[0051] As ACT 3, the processor 31 counts up the second counter N by "1" only. Thereafter, as ACT 4, the processor 31 confirms whether the second counter N exceeds the maximum value "2" of the work buffer number. In the case where the second counter N does not exceed the maximum value "2" of the work buffer number, the processor 31 determines NO in ACT 4, and proceeds to ACT 5. In the case where the second counter N exceeds the maximum value "2" of the work buffer number, the processor 31 determines YES in ACT 4, and returns to ACT 2. Thereafter, the processor 31 temporarily resets the second counter N to "0", and counts up by "1" again, and proceeds to ACT 4. Therefore, in this case, because the second counter N is "1", the processor 31 proceeds to ACT 5. In this way, the processor 31 proceeds to ACT 5 in the case where the second counter N is "1" or "2", that is, in the case where the value as the work buffer number exists.

[0052] As ACT5, the processor 31 causes a timer to start counting. The timer is, for example, a software timer whose timeout time is set to 2 seconds and which restarts each time the timeout occurs.

[0053] As ACT6, the processor 31 monitors whether the timer has timed out. In the case where the timer has not timed out, as ACT7, the processor 31 confirms whether the wireless tag has been read out by the reader / writer 10, 20. In the case where the wireless tag has not been read out, the processor 31 determines NO in ACT7 and returns to ACT6. Here, the processor 31 waits for either the timer to time out or the tag ID to be read in ACT6 and ACT7.

[0054] In this waiting-for-acceptance state, when read data of the wireless tag read out by the reader / writer 10, 20 is received via the device interface 38, 39, the processor 31 determines YES in ACT7 and proceeds to ACT8.

[0055] As described above, the read data of the wireless tag output from the reader / writer 10, 20 to the mobile monitoring device 30 includes the tag ID, the antenna ID, and the RSSI. As ACT8, the processor 31 acquires the tag ID and the antenna ID from the read data. In addition, as ACT9, the processor 31 acquires the RSSI from the same read data.

[0056] As ACT10, the processor 31 searches for the work buffer 321, 322 whose value of the second counter N is the work buffer number. Hereinafter, a case where the value of the second counter N is "1", that is, the work buffer 321 is searched for will be exemplified. Further, in the case where the value of the second counter N is "2", that is, the work buffer 322 is searched for, the searched-for work buffer 321 will be replaced with the work buffer 322 in the following description.

[0057] The processor 31 searches for the searched-for work buffer 321 with the tag ID and the antenna ID acquired from the read data as search keys. Thereafter, the processor 31 confirms whether a data record including the tag ID and the antenna ID as its search keys exists in the searched-for work buffer 321. Hereinafter, the data record including the tag ID and the antenna ID as search keys will be referred to as an object data record.

[0058] In the absence of the object data record, the processor 31 determines NO in ACT 11, and proceeds to ACT 12. As ACT 12, the processor 31 appends a data record including the tag ID and the antenna ID as the search keyword in the search object work buffer 321, that is, appends the object data record. After this, the processor 31 proceeds to ACT 13. In the presence of the object data record in the search object work buffer 321, the processor 31 determines YES in ACT 11, skips the processing of ACT 12, and proceeds to ACT 13.

[0059] As ACT 13, the processor 31 increases the read count R of the object data record by "1" only. In addition, as ACT 14, the processor 31 adds the RSSI acquired from the read data to the RSSI aggregate Q of the object data record. When the above processing is ended, the processor 31 returns to ACT 6.

[0060] Thus, the processor 31 repeatedly executes the processing of ACT 8 to ACT 14 each time the data of the wireless tag 2 is read by the reader / writer 10, 20 within the unit time before the timer expires. After this, when the timer expires, the processor 31 determines YES in ACT 6, and proceeds to ACT 15.

[0061] As ACT 15, the processor 31 counts up the first counter T by "1" only. After this, as ACT 16, the processor 31 executes the log production processing. In addition, as ACT 17, the processor 31 executes the region designation processing. The log production processing and the region designation processing will be described later.

[0062] When the log production processing and the region designation processing are ended, the processor 31 returns to ACT 3. That is, the processor 31 counts up the second counter N by "1" only. Therefore, in the case where the second counter N has been "1", the processor 31 makes the second counter N "2". In the case where the second counter N has been "2", the processor 31 makes the second counter N "1". Then, the processor 31 executes the processing after ACT 5 as described above. Therefore, in the case where the search object work buffer in the last processing is the work buffer 321, in this processing, the work buffer 322 is the search object.

[0063] Thus, in the work buffers 321, 322 which become the search object, the tag ID of the wireless tag 2 read within the unit time counted by the timer, the antenna ID of the reader / writer 10, 20 which read out the tag ID, the read count of the same tag ID, and the aggregate value (RSSI aggregate) of the RSSI at the time when the same tag ID is read out are stored.

[0064] Figure 7is a flowchart showing the main sequence of the log production process. When the log production process is entered, the processor 31 selects, as ACT 21, the work buffer 321, 322 whose value of the second counter N is the work buffer number. That is, in the case where the second counter N is "1", the processor 31 selects the work buffer 321. In the case where the second counter N is "2", the processor 31 selects the work buffer 322. Hereinafter, the case where the work buffer 321 is selected will be exemplified. In the case where the work buffer 322 is selected, the selected work buffer 321 will be replaced with the work buffer 322 in the following description.

[0065] The processor 31 confirms, as ACT 22, whether or not a data record is stored in the selected work buffer 321. In the case where the selected work buffer 321 does not store a data record, the processor 31 determines NO in ACT 22. The processor 31 omits the log production process.

[0066] In the case where at least one data record is stored in the selected work buffer 321, the processor 31 determines YES in ACT 22, and proceeds to ACT 23. The processor 31 acquires, as ACT 23, a data record which is not processed by the log production process from the selected work buffer 321. Hereinafter, the acquired unprocessed data record will be referred to as unprocessed record X. The processor 31 confirms, as ACT 24, whether or not another unprocessed data record including the tag ID of the unprocessed record X is stored in the selected work buffer 321.

[0067] In the case where the data of the wireless tag 2 moving in the passage 300 is read out only by either of the readers / writers 10, 20 in the latest unit time, only one data record including the tag ID of the wireless tag 2 exists in the work buffer 321. In this case, the processor 31 determines NO in ACT 24, and proceeds to ACT 25. The processor 31 confirms, as ACT 25, whether or not the read count R of the data record is greater than or equal to the threshold value S.

[0068] For example, the readers / writers 10, 20 have a case where data of the wireless tag 2 located outside the wireless tag readable area 110, 210 is read due to reflection, scattering, or the like of the electric wave. However, such a misread is single, and thus is not read a prescribed number of times in the unit time. Therefore, the prescribed number of times is set as the threshold value S. In the case where the read count R is smaller than the threshold value S, the processor 31 discards the data record generated by the misread. That is, the processor 31 determines NO in ACT 25, and proceeds to ACT 30 by skipping the processes of ACT 26 and ACT 27.

[0069] In the case where the number of readings R is equal to or greater than the threshold value S, the processor 31 determines YES in ACT 25, and proceeds to ACT 26. As ACT 26, the processor 31 creates log data, and saves it in the log file 332. The time of the log data is the value of the first counter T. The tag ID and the antenna ID are the data of the unprocessed record X. As ACT 27, the processor 31 sets the state of this log data to "1". Thereafter, the processor 31 proceeds to ACT 30.

[0070] On the other hand, in the case where the data of the wireless tag 2 moving in the lane 300 is read out by both of the readers / writers 10, 20 in the latest unit time, there are two data records including the tag ID of this wireless tag 2 in the work buffer 321. In this case, the processor 31 determines YES in ACT 24, and proceeds to ACT 28. As ACT 28, the processor 31 acquires another data record including the tag ID of the unprocessed record X from the work buffer 321 which is the selection target. Hereinafter, the acquired another data record will be referred to as an unprocessed record Y. As ACT 29, the processor 31 executes the determination processing using the unprocessed record X and the unprocessed record Y.

[0071] Figure 8 is a flowchart showing the main sequence of the determination processing. When the determination processing is entered, as ACT 41, the processor 31 confirms whether or not the number of readings Rx of the unprocessed record X is equal to or greater than the threshold value S. When the number of readings Rx is less than the threshold value S, the processor 31 determines NO in ACT 41, and proceeds to ACT 42. As ACT 42, the processor 31 confirms whether or not the number of readings Ry of the unprocessed record Y is equal to or greater than the threshold value S. In the case where the number of readings Ry is less than the threshold value S, the processor 31 determines NO in ACT 42, and omits the determination processing. In correspondence with this, in the case where the number of readings Ry is equal to or greater than the threshold value S, the processor 31 determines YES in ACT 42, and proceeds to ACT 49. The processing after ACT 49 will be described later.

[0072] In the case where the number of readings Rx is equal to or greater than the threshold value S, the processor 31 determines YES in ACT 41, and proceeds to ACT 43. As ACT 43, the processor 31 confirms whether or not the number of readings Ry of the unprocessed record Y is equal to or greater than the threshold value S. In the case where the number of readings Ry is less than the threshold value S, the processor 31 determines NO in ACT 43, and skips the processing of ACT 44 to ACT 47, and proceeds to ACT 48.

[0073] In the case where the number of readings Ry is also equal to or greater than the threshold value S, the processor 31 determines YES in ACT43, and proceeds to ACT44. As ACT44, the processor 31 sets the processing flag F to "1". The processing flag F is, for example, 1-bit data stored in a volatile region of the main memory 32.

[0074] As ACT45, the processor 31 divides the RSSI total Q of the unprocessed record X by the number of readings Rx of the same unprocessed record X. That is, the processor 31 calculates the average value Ax of the RSSI at the time when the tag ID of the wireless tag 2 is read out by the reader / writer of one side, for example, the reader / writer 10, in a unit time.

[0075] As ACT46, the processor 31 divides the RSSI total Q of the unprocessed record Y by the number of readings Ry of the same unprocessed record Y. That is, the processor 31 calculates the average value Ay of the RSSI at the time when the tag ID of the same wireless tag 2 is read out by the reader / writer of the other side, for example, the reader / writer 20, in a unit time.

[0076] As ACT47, the processor 31 compares the average value Ax and the average value Ay. As a result thereof, when the average value Ax is greater than the average value Ay, the processor 31 determines YES in ACT47, and proceeds to ACT48. When the average value Ay is equal to or greater than the average value Ax, the processor 31 determines NO in ACT47, and proceeds to ACT49.

[0077] Thus, in the case where the number of readings Rx of the unprocessed record X is equal to or greater than the threshold value S, and the number of readings Ry of the unprocessed record Y is less than the threshold value S, the processor 31 proceeds to ACT48. In the case where the number of readings Ry of the unprocessed record Y is equal to or greater than the threshold value S, and the number of readings Rx of the unprocessed record X is less than the threshold value S, the processor 31 proceeds to ACT49. In the case where the numbers of readings Rx, Ry of the unprocessed record X and the unprocessed record Y are both equal to or greater than the threshold value S, the processor 31 compares the average value Ax of the RSSI calculated from the unprocessed record X and the average value Ay of the RSSI calculated from the unprocessed record Y. Thereafter, in the case where the average value Ax is greater than the average value Ay, the processor 31 proceeds to ACT48. In the case where the average value Ay is equal to or greater than the average value Ax, the processor 31 proceeds to ACT49.

[0078] In ACT48, the processor 31 selects the unprocessed record X. In ACT49, the processor 31 selects the unprocessed record Y. Thereafter, when the processing of ACT48 or ACT49 ends, the processor 31 proceeds to ACT50.

[0079] As the ACT 50, the processor 31 makes log data using the selected unprocessed record X or unprocessed record Y, and saves it in the log file 332. The time of the log data is the value of the first counter T. The tag ID and the antenna ID are the data of the unprocessed record X or unprocessed record Y.

[0080] As the ACT 51, the processor 31 investigates the processing flag F. Here, in the case where the processing flag F has not been set to "1", the processor 31 determines NO in the ACT 51, and proceeds to the ACT 52. As the ACT 52, the processor 31 sets the state of the log data saved in the log file 332 in the processing of the ACT 50 to "1". Thereafter, the processor 31 omits the determination processing.

[0081] In the case where the processing flag F has been set to "1", the processor 31 determines YES in the ACT 51, and proceeds to the ACT 53. As the ACT 53, the processor 31 sets the state of the log data saved in the log file 332 in the processing of the ACT 50 to "2". In addition, as the ACT 53, the processor 31 resets the processing flag F to "0". Thereafter, the processor 31 omits the determination processing.

[0082] Thus, in the log making processing, the log data is made based on the data records in the selected work buffer 321 in which the read count R is greater than or equal to the threshold value S, and is saved in the log file 332. At this time, in the case where the tag ID for which the read count R of the reader / writer 10 is greater than or equal to the threshold value S is not greater than or equal to the threshold value S in the read count R by the reader / writer 20, the antenna ID of the log data is the antenna ID of the antenna 11. Conversely, in the case where the tag ID for which the read count R by the reader / writer 20 is greater than or equal to the threshold value S is not greater than or equal to the threshold value S in the read count R by the reader / writer 10, the antenna ID of the log data is the antenna ID of the antenna 21. In addition, the state of the log data is all "1".

[0083] On the other hand, in the case where the read count R of the same tag ID by both the reader / writers 10, 20 is greater than or equal to the threshold value S, the average values Ax, Ay of the RSSI are compared. Thereafter, the antenna ID of the antenna 11, 21 of the reader / writer 10, 20 corresponding to the larger one of the average values Ax, Ay is included in the log data. In addition, the state of the log data is "2".

[0084] Thus, the log data produced by the log production processing performed corresponding to each unit time is saved in the log file 332 in chronological order. In addition, the log data means that the wireless tag 2 identified by the tag ID was located in the wireless tag readable area 110, 120 of the antenna 11, 21 identified by the antenna ID at the time T.

[0085] Thus, by analyzing the log data in chronological order, the moving direction of the wireless tag 2 in the passage 300 is detected. That is, it is possible to detect whether the wireless tag 2 moved from the wireless tag readable area 110 of the antenna 11 to the wireless tag readable area 210 of the antenna 21, that is, in the direction indicated by the arrow Da, or whether the wireless tag 2 moved from the wireless tag readable area 210 of the antenna 21 to the wireless tag readable area 110 of the antenna 11, that is, in the direction indicated by the arrow Db. Figure 1 Figure 1

[0086] Figure 9 is a flowchart showing the order of the main parts of the area specifying processing. When the area specifying processing is entered, the processor 31 retrieves the log file 332 as ACT 61. Thereafter, the processor 31 confirms whether the log data of the time (T-1) which is only one less than the value of the first counter T is saved as ACT 62. Hereinafter, the log data of the time (T-1) is referred to as first target log data. The processor 31 determines NO in ACT 62 in the case where the first target log data is not saved in the log file 332. The processor 31 omits the area determining processing.

[0087] When the first target log data is saved in the log file 332, the processor 31 determines YES in ACT 62 and proceeds to ACT 63. The processor 31 acquires the tag ID from the first target log data as ACT 63. Thereafter, the processor 31 retrieves the log file 332 using the tag ID as a search key as ACT 64. Thereafter, the processor 31 confirms whether the log data of the time T which is the value of the first counter T is saved as ACT 64. Hereinafter, the log data of the time T is referred to as second target log data. The processor 31 determines YES in ACT 65 in the case where the second target log data is saved in the log file 332. The processor 31 skips ACT 66 to ACT 69 and proceeds to ACT 70.

[0088] When the second target log data is not saved in the log file 332, the processor 31 determines NO in ACT 65. The processor 31 performs the processing of ACT 66 to ACT 69 and proceeds to ACT 70.

[0089] ​​That is, as ACT 66, the processor 31 acquires the date and time data clocked by the clock 34. In addition, as ACT 67, the processor 31 acquires the antenna ID from the first target log data. Thereafter, as ACT 68, the processor 31 converts the antenna ID to the area name with reference to the conversion table 331. Thereafter, as ACT 69, the processor 31 saves the determination data in the determination file 333. The date and time of the determination data is the date and time data acquired in the processing of ACT 66. The tag ID is the tag ID of the first target log data. The area name is the area name converted from the antenna ID in the processing of ACT 68.

[0090] As ACT 70, the processor 31 confirms whether or not the search of the log file 332 has ended. In the case where the search of the log file 332 has not ended, that is, in the case where other first target log data is saved in the log file 332, the processor 31 determines NO in ACT 70 and returns to ACT 63. Thereafter, the processor 31 executes the processing after ACT 63 as described above.

[0091] In this way, with respect to the first target log data saved in the log file 332, the processor 31 determines YES in ACT 70 when the execution of the processing after ACT 63 ends. The processor 31 omits the area designation processing.

[0092] In such area designation processing, it is determined whether or not second target log data with respect to the first target log data is saved in the log file 332. The first target log data is the log data of a time (T-1) which is only one less than the value of the first counter T. The second target log data is the log data which is included in the log data of the time of the value of the first counter T and which contains the same tag ID as the first target log data. The second target log data can also differ from the first target log data in at least one of the antenna ID and the state.

[0093] In the case where the second target log data with respect to the first target log data is saved in the log file 332, the processing of ACT 66 to ACT 69 is not executed. The processing of ACT 66 to ACT 69 is executed only in the case where the second target log data with respect to the first target log data is not saved in the log file 332. That is, in the case where the tag ID of the wireless tag 2 whose number of times of reading by at least one of the readers / writers 10, 20 in the previous unit time is greater than or equal to the threshold value S is not read out in the subsequent unit time, the determination data is made using the first target log data and is saved in the determination file 333.

[0094] In a case where the tag ID read out in the preceding unit time is not read out in the succeeding unit time, it is considered that the wireless tag 2 of the tag ID moves in the passage 300 and is transferred to the first area 100 or the second area 200.

[0095] Thus, the determination data including the tag ID of the wireless tag 2 moving in the passage 300 and being transferred to the first area 100 or the second area 200, the area name indicating the transfer destination, and the transfer date and time is saved in the determination file 333.

[0096] Therefore, by analyzing the determination data, it is possible to manage whether the article 3 attached with the wireless tag 2 moves in the passage 300 and is transferred from the first area 100 to the second area 200 or is transferred from the second area 200 to the first area 100.

[0097] Incidentally, in the present embodiment, the determination data saved in the determination file 333 is outputted from the movement monitoring device 30 to the article management device 40 every prescribed time, for example, 1 minute. In the article management device 40, the area name and the date and time of the tag record 410 are updated based on the determination data. Therefore, by analyzing the data record 410 saved in the tag database 41, it is possible to correctly specify the presence area of the article 3 at the current time point.

[0098] Here, the movement monitoring device 30 constitutes the number of times acquisition section by executing the processing of ACT 13 by the processor 31. Figure 6 That is, the movement monitoring device 30 acquires the number of times R of reading out the data of the wireless tag 2 by the plurality of antennas 11, 21 respectively, for each antenna, for each unit time.

[0099] The movement monitoring device 30 constitutes the strength acquisition section by executing the processing of ACT 14 by the processor 31. Figure 6 That is, the movement monitoring device 30 acquires the RSSI at the time of reading out the data of the wireless tag 2 by the plurality of antennas 11, 21 respectively, for each antenna, for each unit time.

[0100] The movement monitoring device 30 constitutes the direction specification section by executing the processing of ACT 23 to 29 by the processor 31. Figure 7 That is, the movement monitoring device 30 specifies the moving direction of the wireless tag 2 to and from the passage 300 based on the number of times and the RSSI acquired for each antenna for each unit time.

[0101] Specifically, the movement monitoring device 30, in a case where the antenna whose read frequency is equal to or greater than the prescribed number is only one in the unit time, considers that the wireless tag 2 passes near the antenna, and specifies the movement direction of the wireless tag 2. In addition, in a case where the antenna whose read frequency is equal to or greater than the prescribed number is plural, considers that the wireless tag 2 passes near the antenna whose RSSI is the highest among the compared antennas in the unit time, and specifies the movement direction of the wireless tag 2.

[0102] Here, when the antennas whose read frequency is equal to or greater than the prescribed number are plural in the unit time, the RSSI of each of the compared antennas is an average value when the data of the wireless tag 2 is read in the unit time.

[0103] In addition, the movement monitoring device 30 constitutes the area specifying section by the processor 31 executing the processing of the ACT 61 to 70. Figure 9 That is, the movement monitoring device 30 specifies the existence area of the wireless tag 2 moving in the passage 300 from the movement direction of the wireless tag 2 specified by the passage direction specifying section.

[0104] Specifically, the movement monitoring device 30, in a case where the data of the wireless tag 2 read by at least one antenna is not read again, specifies the existence area from the movement direction of the wireless tag 2 last specified by the passage direction specifying section.

[0105] According to the wireless tag reading device 1 including the movement monitoring device 30 thus constituted, and provided with two wireless tag communication antennas 11, 21 along the passage 300 where the wireless tag 2 comes and goes, the movement direction of the wireless tag 2 coming and going in the passage 300 can be specified with good accuracy. In particular, in the movement monitoring device 30, the movement direction of the wireless tag 2 is specified based not only on the read frequency of each antenna obtained in each unit time, but also on the received signal strength at that time. Therefore, compared with the prior art in which the movement direction of the wireless tag is specified based on the time when the plurality of antennas communicate with the wireless tag, or the number of times when the data of the wireless tag is read, the movement direction of the wireless tag 2 can be specified with high accuracy.

[0106] Thus far, the embodiment of the wireless tag reading device has been described, but the related embodiments are not limited to this.

[0107] Figure 10 is an example of the image 50 displayed on the display device 36. The image 50 is created from the log data saved in the log file 332 and the determination data saved in the determination file 333.

[0108] The image 50 includes display areas 51 to 58. The display area 51 is an area for displaying a tag ID of log data or determination data. The display area 52 is an area for displaying a state of the log data. The display area 53 is an area for displaying a state of the determination data.

[0109] With respect to the tag ID existing as the log data and not existing as the determination data, the latest time log data is selected. Thereafter, the tag ID of the log data is displayed in the display area 51. In addition, in the case where the antenna ID of the log data is the antenna ID of the antenna 11 and the state is "1", a circular mark is displayed on an area ANTa on the left side of the display area 52, and in the case where the state is "2", a double circular mark is displayed on the same area ANTa. Similarly, in the case where the antenna ID of the log data is the antenna ID of the antenna 11 and the state is "1", a circular mark is displayed on an area ANTb on the right side of the display area 52, and in the case where the state is "2", a double circular mark is displayed on the same area ANTb.

[0110] With respect to the tag ID existing as the determination data, the latest date and time log data, that is, the log data corresponding to a unit time before the determination data is made, is selected. Thereafter, the antenna ID of the log data is displayed in the display area 51. In addition, in the case where the antenna ID of the log data is the antenna ID of the antenna 11 and the state is "1", a circular mark is displayed on an area AREAa on the left side of the display area 53, and in the case where the state is "2", a double circular mark is displayed on the same area AREAa. Similarly, in the case where the antenna ID of the log data is the antenna ID of the antenna 11 and the state is "1", a circular mark is displayed on an area AREAb on the right side of the display area 53, and in the case where the state is "2", a double circular mark is displayed on the same area AREAb.

[0111] The number of the tag IDs displayed in the display area 51 is displayed in the display area 54. The number of the marks displayed in the display area 52 is displayed in the display area 55, respectively corresponding to the areas ANT a, ANTb. The number of the marks displayed in the display area 53 is displayed in the display area 56, respectively corresponding to the areas AREAa, AREAb. The value of the first counter T is displayed in the display area 57. The unit time is displayed in the display area 58.

[0112] By causing such an image 50 to be displayed in the display device 36, it is possible to acquire the following information in real time.

[0113] If the number of times tag ID "1111111111" is read by both antennas 11 and 21 is greater than or equal to the threshold S, the average RSSI of antenna 11 is high. Therefore, wireless tag 2 with tag ID "1111111111" is located near antenna 11.

[0114] The number of times tag ID "2222222222" was read through antenna 11 was greater than or equal to the threshold S, while the number of times it was read through antenna 21 was not greater than or equal to the threshold S. Therefore, wireless tag 2 with tag ID "2222222222" is located near antenna 11.

[0115] The tag ID "3333333333" is no longer read after being read more than or equal to the threshold S by antenna 11. Therefore, wireless tag 2 with tag ID "3333333333" exists in the first area 100.

[0116] The number of times tag ID "4444444444" was read by both antenna 11 and antenna 21 is greater than or equal to the threshold S, and the average RSSI of antenna 21 is high. Therefore, wireless tag 2 with tag ID "4444444444" is located near antenna 21.

[0117] Once the number of reads of tag ID "5555555555" through both antennas 11 and 21 exceeds a threshold S, it will no longer be read. Furthermore, when read through both antennas 11 and 21, the average RSSI of antenna 21 is higher. Therefore, wireless tag 2 with tag ID "3333333333" exists in the second area 200.

[0118] In the described embodiment, Figure 8 In ACT47, unprocessed record X is selected when the average value Ax is higher than the average value Ay, and unprocessed record Y is selected when the average value Ay is greater than or equal to the average value Ax. Alternatively, unprocessed record X can be selected when the average value Ax is greater than or equal to the average value Ay, and unprocessed record Y can be selected when the average value Ay is higher than the average value Ax. Or, unprocessed record X can be selected when the average value Ax is higher than the average value Ay, unprocessed record Y can be selected when the average value Ay is higher than the average value Ax, and neither is selected when the average value Ax and the average value Ay are equal.

[0119] In the embodiment, the number of antennas 11, 21 arranged along the passage 300 is two. The number of antennas is not limited to two. Three or more antennas can be arranged along the passage 300. In addition, a plurality of antennas can be arranged on both sides of the passage 300. It is important that a plurality of antennas are arranged appropriately in accordance with the length, shape, and the like of the passage 300.

[0120] In the embodiment, the mobile monitoring device 30 and the commodity management device 40 are separate computer devices. The mobile monitoring device 30 and the commodity management device 40 can be constituted by one computer device.

[0121] The program related to the embodiment can be transferred in a state stored in an electronic device, or in a state not stored in an electronic device. In the latter case, the program can be transferred via a network, or in a state stored in a storage medium. The storage medium is a non-transitory tangible medium. The storage medium is a computer-readable medium. The form of the storage medium is not limited as long as it is a medium that can store a program, such as a CD-ROM, a memory card, and the like, and is computer-readable.

[0122] In addition, although several embodiments of the present application have been described, these embodiments are presented as examples and are not intended to limit the scope of the application. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, modifications, and the like can be made without departing from the scope of the application. In addition, these embodiments and modifications thereof are included in the scope of the application, and are included in the scope of the application and equivalents thereof recited in the claims.

Claims

1. A wireless tag reading device, characterized in that, include: Multiple antennas are configured along the path of the wireless tag for wireless tag communication; The number acquisition unit acquires, within each unit time period, the number of times the data of the wireless tag is read by the multiple antennas respectively within the unit time period; The strength acquisition unit acquires the received signal strength of each antenna when the data of the wireless tag is read by the plurality of antennas in the unit time, respectively. as well as The direction designation unit, based on the number of reads and the received signal strength of each of the multiple antennas obtained in each unit time, generates log data indicating which antenna the wireless tag is near in each unit time, analyzes the generated log data in chronological order, and designates the movement direction of the wireless tag traveling to and from the channel.

2. The wireless tag reading device according to claim 1, wherein, If, within a unit of time, there is only one antenna whose number of reads is greater than or equal to a predetermined number, the directional designator considers the wireless tag to be located near that antenna and generates the log data. If there are multiple antennas whose number of reads is greater than or equal to the predetermined number, the directional designator considers the wireless tag to be located near the antenna with the highest received signal strength among all antennas and generates the log data.

3. The wireless tag reading device according to claim 2, wherein, In the case where there are multiple antennas that have read data more than or equal to a predetermined number of times within the unit time period, the received signal strength of each antenna being compared is the average value when the data of the wireless tag is read within the unit time period.

4. The wireless tag reading device according to claim 1, further comprising: The area designation unit designates the area in which the wireless tag moving in the channel exists, based on the direction of movement of the wireless tag designated by the direction designation unit.

5. The wireless tag reading device according to claim 4, wherein, When the data of the wireless tag read by at least one antenna is no longer read, the area designation unit designates the area based on the movement direction of the wireless tag last designated by the direction designation unit.

6. A method for reading wireless tags, in a wireless tag reading device having multiple antennas for wireless tag communication configured along a channel for wireless tag travel, the method comprising the following steps: Within each unit of time, the number of times each antenna reads the data of the wireless tag through the multiple antennas within the unit of time is recorded; Within each unit time period, the received signal strength corresponding to each antenna when the data of the wireless tag is read by the plurality of antennas respectively within the unit time period is obtained; as well as Based on the number of reads and the received signal strength of each antenna within each unit time period, log data indicating which antenna the wireless tag is near is generated within each unit time period. The generated log data is analyzed in chronological order to specify the movement direction of the wireless tag traveling to and from the channel.

7. A program storage medium storing a control program that causes a computer of a wireless tag reader, in which a plurality of wireless tag communication antennas are configured along a path for wireless tags to travel, to execute the following functions, said functions including: Within each unit of time, the number of times each antenna reads data from the wireless tag through the multiple antennas within that unit of time is recorded; Within each unit time period, the received signal strength corresponding to each antenna when the data of the wireless tag is read by the plurality of antennas respectively within the unit time period is obtained; as well as Based on the number of reads and the received signal strength of each antenna within each unit time period, log data indicating which antenna the wireless tag is near is generated within each unit time period. The generated log data is analyzed in chronological order to specify the movement direction of the wireless tag traveling to and from the channel.

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