JP2009093434A - Wireless tag reading device and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To alleviate a load of a host system when attaching a plurality of wireless tags to one article. <P>SOLUTION: A part of individual data of a plurality of wireless tags read by a tag reading means are masked. In each of the data of the plurality of wireless tags read by the tag reading means, it is determined whether portions other than the masked are overlapped or not. When there are a plurality of wireless tag data of which the portions other than the masked are overlapped, one of them is selected and the rest are canceled. The selected wireless tag data is transmitted to the host device. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a wireless tag reader of a recognition system using a wireless tag and a reading method thereof.

  In recent years, recognition systems for articles and the like using wireless tags have been devised. This system reads wireless tag data attached to an object with a wireless tag reader and transmits it to a host device, and collates the wireless tag data with preset object information with a wireless device. It recognizes an object with a tag.

In such a recognition system, conventionally, a plurality of wireless tags each storing the same object information are attached to one object, and the object is recognized by reading the data of each wireless tag with a wireless tag reader. The system is known. With such a system, since the probability that the object information can be read from the wireless tag is extremely high, it is possible to perform object recognition quickly and with high accuracy (see, for example, Patent Document 1).
JP 2005-157869 A

  When attaching a plurality of wireless tags to one object, the object information stored in each wireless tag can be the same. However, the tag identification information set for each wireless tag must be different. Therefore, the wireless tag data combining the object information and the tag identification information is different for each wireless tag.

  The wireless tag reader has a duplication check function for discarding one of the same wireless tag data when it is read. However, if even part of the data is different, all the read data is transmitted to the host device. For this reason, there is a concern that the load on the host device becomes larger than when one wireless tag is attached to one object. There is also a concern that the amount of communication traffic between the wireless tag reading device and the host device also increases.

  The present invention has been made based on such circumstances. The object of the present invention is to reduce the amount of wireless tag data transmitted to a host device to 1 even when a plurality of wireless tags are attached to one object. An object of the present invention is to provide a wireless tag reader and method that can be reduced to the same level as when only one is attached.

  The wireless tag reader of the present invention is a wireless tag reader that reads data of a plurality of wireless tags by a tag reader and transmits the data to a host device, and each of the data of a plurality of wireless tags read by the tag reader. A mask processing means for masking a part, a duplication determination means for judging whether or not each of the data of a plurality of wireless tags read by the tag reading means overlaps other than a portion masked by the mask processing means, When there are a plurality of RFID tag data other than those masked by the duplication judgment means, one of them is selected and the rest is discarded, and the RFID tag data selected by this duplication processing means And tag data transmitting means for transmitting to the apparatus.

  The wireless tag reading method of the present invention includes a tag reading step for reading data of a plurality of wireless tags by wireless communication, and a mask process for masking a part of each of the data of the plurality of wireless tags read by the tag reading step. A duplication determination step for determining whether or not a portion other than the portion masked by the mask processing step is duplicated for each of the data of the plurality of wireless tags read by the step and the tag reading step, and masked by the duplication determination step When there are a plurality of RFID tag data that are duplicated except for the part, a duplicate processing step for selecting one of them and discarding the rest, and tag data transmission for sending the RFID tag data selected in this duplicate processing step to the host device And a step.

  According to the present invention in which such measures are taken, even when a plurality of wireless tags are attached to one article, the data amount of the wireless tag data transmitted to the host system is reduced to the same level as when only one piece is attached. It is possible to provide a wireless tag reader and method that can be used.

The best mode for carrying out the present invention will be described below with reference to the drawings.
This embodiment manages the arrival / shipment of goods by reading the data of the wireless tag attached to the product and the data of the wireless tag attached to the pallet for carrying the product. This is a case where the present invention is applied to a wireless tag reader of a physical distribution management system.

(First embodiment)
FIG. 1 is a configuration diagram of a system constructed on the physical distribution base side of the physical distribution management system in the first embodiment. The distribution base refers to a base such as a wholesaler that receives and ships merchandise and a retailer that receives and sells merchandise.

  As shown in the figure, a wireless tag reader / writer 1 (hereinafter abbreviated as a reader / writer 1) 1 and a client computer 2 (hereinafter abbreviated as a client 2) are provided at the distribution base. The reader / writer 1 functions as a wireless tag reader according to the present invention. The client 2 functions as a host device of the reader / writer 1. The reader / writer 1 and the client 2 are connected by a transmission cable 3. Although not shown, the client 2 is connected via a network to a server computer (hereinafter abbreviated as a server) installed at the headquarters of each distribution base.

  The reader / writer 1 includes an antenna 4. The antenna 4 is a loop coil antenna, a dipole antenna, a planar patch antenna, or the like. The reader / writer 1 reads wireless tag data existing in the communication area of the antenna 4 in a contactless manner using wireless communication, and reads the read wireless tag data to the client 2 through the transmission path 3. Send. At this time, the reader / writer 1 can continuously read data of these wireless tags when there are a plurality of wireless tags in the communication area by using a collision prevention function called anti-collision. .

  In FIG. 1, reference numeral 5 indicates a rectangular pallet, and 6 a and 6 b indicate products conveyed by the pallet 5. Wireless tags 7a, 7b, 7c, and 7d (7c and 7d are not shown) are attached to the pallet 5 at four locations on the side surface thereof. Wireless tags 8a and 8b (8b are not shown) and 9a and 9b (9b are not shown) are attached to each of the products 6a and 6b at two locations on the front and back sides, respectively.

  The data stored in these wireless tags 7a, 7b, 7c, 7d, 8a, 8b, 9a, 9b, that is, so-called wireless tag data has a common structure. That is, as shown in FIG. 2, the wireless tag data is composed of header data D1, an article identification code D2, and a serial number D3.

  The header data D1 is data indicating the number of wireless tags attached to tag attachment objects such as products and pallets, and is composed of 1 byte. In the present embodiment, when the number of wireless tags attached to the tag attachment object is “1”, “00110000” = 30 h as shown in the record R1. When the number of wireless tags is “2”, “00110001” = 31h is set as shown in the records R21 and R22. When the number of wireless tags is “4”, “00110010” = 32h is set as shown in the records R31, R32, R33, and R34. For example, in the case of wireless tags 7a, 7b, 7c, and 7d attached to the pallet 5, the number of wireless tags is “4”, so “00110010”. On the other hand, in the case of the wireless tags 8a, 8b, 9a, 9b attached to the products 6a, 6b, since the number of wireless tags is “2”, “00110001” = 31h.

  The article identification code D2 is information for identifying a tag attachment target (pallet 5, products 6a, 6b, etc.), and is composed of a plurality of bytes of data. For example, in the case of the wireless tags 7a, 7b, 7c, and 7d attached to the pallet 5, the ID unique to the pallet is the article identification code D2. In the case of the wireless tags 8a, 8b, 9a, and 9b attached to the products 6a and 6b, the manufacturer code, the product code, and the like of the product are the product identification code D2. That is, when a plurality of wireless tags are attached to the same tag attachment object, the article identification code D2 of each wireless tag is common.

  The serial number D3 is data for individually identifying a wireless tag attached to one tag attachment object, and is formed of 1-byte data. In this embodiment, in the case of a wireless tag with only one object attached, “00000000” = 00h as shown in the record R1. In the case of two wireless tags attached to the object, one is set to “00000000” = 00h as shown in the record R21, and the other is set to “00000001” = 01h as shown in the record R22. In the case of four wireless tags attached to the object, one is set to “00000000” = 00h as shown in the record R31, and another one is set to “00000001” = 01h as shown in the record R32. Another one is “00000010” = 02h as shown in record R33, and the other one is “00000011” = 03h as shown in record R34. Similarly, although not shown, in the case of eight wireless tags attached to an object, each is set to one of “00000000” = 00h to “00000111” = 07h.

  For example, in the case of the wireless tags 7a, 7b, 7c, and 7d attached to the pallet 5, since four wireless tags are attached, "00000000", "00000001", "00000010", and "00000011" Assigned. On the other hand, in the case of the wireless tags 8a, 8b, 9a, and 9b attached to the products 6a and 6b, since two wireless tags are attached, “00000000” and “00000001” are assigned to each.

  FIG. 3 is a block diagram showing a main configuration of the reader / writer 1. The reader / writer 1 includes an interface 11, a modulation unit 12, a transmission amplifier 13, a reception amplifier 14, a demodulation unit 15, a circulator 16, and a control unit 17.

  The interface 11 manages data communication between the control unit 17 and the client 2. The modulation unit 12 modulates the transmission data given from the control unit 17. The transmission amplifier 13 amplifies the data signal modulated by the modulation unit 12. The circulator 16 supplies the data signal amplified by the transmission amplifier 13 to the antenna 4. In addition, a signal corresponding to the radio wave received by the antenna 4 is supplied to the reception amplifier 14. The reception amplifier 14 amplifies the received radio wave signal. The demodulator 15 demodulates the signal amplified by the reception amplifier 14 and supplies the demodulated signal to the controller 17.

  The control unit 17 includes a memory 20. As shown in FIG. 4, the memory 20 includes storage areas of a transmission buffer memory 21, a pre-mask processing memory 22, a table memory 23, and a flag memory 24. The transmission buffer memory 21 is an area for storing a plurality of RFID tag data whose reading has been confirmed. The pre-mask processing memory 22 is an area for temporarily storing the RFID tag data demodulated by the demodulator 15.

  The table memory 23 is an area in which mask data M is stored in advance corresponding to each of the header data D1. The mask data M is data for masking a part of the serial number D3, and by masking a part of the serial number D3, among the data of a plurality of wireless tags attached to the same tag attachment object This is for making the parts other than the masked part common.

  That is, the mask data M = “11111111” is set for the header data D1 = “00110000”. Only one wireless tag of the header data D1 is attached to the tag attachment object. That is, since there is no need for masking, mask data M = “11111111” indicating that all bits of the serial number D3 consisting of 1 byte are not masked is set.

  Mask data M = “11111110” is set for the header data D1 = “00110001”. Two wireless tags of the header data D1 are attached to the tag attachment object, one of which has a serial number D3 of “00000000” and the other of which has a serial number D3 of “00000001”. That is, by masking the least significant 1 bit of the serial number D3, the other portions become the same, so the mask data M = “11111110” is set.

  Mask data M = “11111100” is set for the header data D1 = “00110010”. Four wireless tags of the header data D1 are attached to the tag attachment target, and the serial numbers D3 are “00000000”, “00000001”, “00000010”, and “00000011”, respectively. That is, by masking the least significant 2 bits of the serial number D3, the other parts become the same, so the mask data M = “11111100” is set.

  For header data D1 = "00110011", mask data M = "11111000" is set. Eight wireless tags of the header data D1 are attached to the tag attachment target, and each serial number D3 is “00000000”, “00000001”, “00000010”, “00000011” “00000100”, “00000101”. "00000110" and "00000111". That is, by masking the least significant 3 bits of the serial number D3, the other portions become the same, so the mask data M = “11111000” is set.

  The flag memory 24 is an area for storing a mask designation flag F (F = 1: executed, F = 0 not executed) for designating whether or not to execute the mask processing of the RFID tag data by the mask data M. . In the present embodiment, the mask designation flag F is set (1) or reset (0) by, for example, a command from the client 2 before the RFID tag data reading process described below is started.

  The control unit 17 executes the RFID tag data reading process in the procedure shown in the flowchart of FIG. That is, when receiving a tag reading start command from the client 2 via the interface 11, the control unit 17 starts this process.

  First, the control unit 17 gives data of a tag inquiry command to the modulation unit 12 as ST (step) 1. As a result, the data signal of this command is modulated by the modulation unit 12, amplified by the transmission amplifier 13, and then radiated as a radio wave from the antenna 4. The wireless tag receiving the tag inquiry command radio wave is activated. The activated wireless tag modulates the wireless tag data stored in its own memory into a response radio wave and transmits it. When the antenna 4 receives this response radio wave, a signal corresponding to the response radio wave is supplied to the reception amplifier 14, amplified, and then supplied to the demodulation unit 15. The demodulating unit 15 demodulates the wireless tag data and then supplies the data to the control unit 17.

In the reader / writer 1, every time the response radio wave from the wireless tag is received by the antenna 4, the above-described amplification and demodulation processes are repeated.
The control unit 17 that has transmitted the tag inquiry command waits for a response of the wireless tag data as ST2. Then, every time the wireless tag data demodulated by the demodulator 15 is fetched, the processes after ST3 are executed.

  In ST3, the wireless tag data demodulated by the demodulator 15 is overwritten in the pre-mask processing memory 22. Next, the control unit 17 checks the flag memory 24 as ST4. Here, if the mask designation flag F in the flag memory 24 has been reset, the mask process is not executed, so the process proceeds to ST8 described later.

  On the other hand, when the mask designation flag F is set, the control unit 17 executes a mask process. Specifically, the wireless tag data stored in the pre-mask processing memory 22 is read as ST5. Then, the table memory 23 is searched as ST6, and the mask data M set corresponding to the header data D1 of the RFID tag data is acquired. Next, the control unit 17 calculates a logical product for each bit of the serial number D3 of the RFID tag data read from the pre-mask processing memory 22 as ST7 and the mask data M acquired in the process of ST6. Mask processing is performed on a part of the serial number D3 (mask processing means). Thereafter, the control unit 17 proceeds to the process of ST8.

  In ST8, the control unit 17 executes a duplication check process. That is, if the mask designation flag F is reset in ST4, the transmission buffer memory 21 is searched with the wireless tag data stored in the pre-mask processing memory 22, and the same data is already stored in the transmission buffer memory 21. It is determined whether it is stored. On the other hand, when the mask designation flag F is set, in the RFID tag data read from the pre-masking memory 22, the RFID tag data having the same data as the data other than the portion masked in ST7 Is stored in the transmission buffer memory 21 (duplication determination means).

  As a result of the duplication check process, when it is determined that the data is not stored (NO in ST9), the control unit 17 adds the wireless tag data stored in the pre-mask process memory 22 to the transmission buffer memory 21 as ST10. To do. On the other hand, when it is determined that the data is stored (YES in ST9), the control unit 17 discards the wireless tag data in the pre-mask processing memory 22 as ST11 (duplicate processing means).

  The control unit 17 executes the processes of ST3 to ST11 each time it receives the wireless tag data from the demodulation unit 15 in ST2. Then, when a predetermined time has passed without receiving the RFID tag data, the control unit 17 considers that the reading of the RFID tag data has been completed in ST12. In that case, the control unit 17 transmits the wireless tag data stored in the transmission buffer memory 21 as ST13 to the client 2 (tag data transmission unit), and ends the current reading process.

  As shown in FIG. 1, it is assumed that products 6a and 6b conveyed by the pallet 5 are received at a distribution base where the distribution management system of the present embodiment is constructed. In this case, at the distribution base, a tag reading start command is transmitted from the client 2 to the reader / writer 1 in a state where the pallet 5 on which the products 6 a and 6 b are placed is arranged in the communication area of the antenna 4. Then, the radio wave of the tag inquiry command is radiated from the antenna 4, and the data of the wireless tags 7a, 7b, 7c, 7d, 8a, 8b, 9a, 9b existing in the communication area of the antenna 4 are continuously read.

  Assume that data is read in the order of wireless tags 7d, 7a, 8a, 7c, 8b, 9a, 9b, and 7b. It is assumed that the mask designation flag F is set to “1” before starting reading. Further, it is assumed that the transmission buffer memory 21 is cleared.

  First, the data of the wireless tag 7d is read. Then, since the header data D1 of the wireless tag 7d is “00110010”, the mask data M = “11111100” is selected from the table memory 23. As a result, the lower 2 bits of the serial number D3 of the wireless tag 7d are masked. Here, the serial number D3 of the wireless tag 7d is any one of “00000000”, “00000001”, “00000010”, or “00000011”. Therefore, the part other than the masked area is “000000”. At this time, the wireless tag data is not stored in the transmission buffer memory 21. Therefore, the data of the wireless tag 7d is stored in the transmission buffer memory 21 as it is.

  Next, the data of the wireless tag 7a is read. Then, since the header data D1 of the wireless tag 7a is “00110010”, the mask data M = “11111100” is selected from the table memory 23. As a result, the lower 2 bits of the serial number D3 of the wireless tag 7a are masked. Here, the serial number D3 of the wireless tag 7a is any one of “00000000”, “00000001”, “00000010”, or “00000011”. Therefore, the part other than the masked area is “000000”. At this time, data of the wireless tag 7d is stored in the transmission buffer memory 21. The wireless tag 7d and the wireless tag 7a share the same header data D1 and article identification code D2, and differ only in the lower two digits of the serial number D3. Accordingly, the data other than the masked portion of the wireless tag 7a is overlapped with the data other than the masked portion of the wireless tag 7d by the duplication check process, so the data of the wireless tag 7a is discarded.

  Next, the data of the wireless tag 8a is read. Then, since the header data D1 of the wireless tag 8a is “00110001”, the mask data M = “11111110” is selected from the table memory 23. As a result, the lower 1 bit of the serial number D3 of the wireless tag 8a is masked. Here, the serial number D3 of the wireless tag 8a is either “00000000” or “00000001”. Therefore, the portion other than the masked portion is “0000000”. At this time, data of the wireless tag 7d is stored in the transmission buffer memory 21. The wireless tag 7d and the wireless tag 8a are different in header data D1 and article identification code D2. Therefore, the data of the wireless tag 8a is stored in the transmission buffer memory 21 as it is.

  Next, the data of the wireless tag 7c is read. Then, since the header data D1 of the wireless tag 7c is “00110010”, the mask data M = “11111100” is selected from the table memory 23. Here, the serial number D3 of the wireless tag 7c is any one of “00000000”, “00000001”, “00000010”, or “00000011”. Therefore, processing is performed in the same manner as when the data of the wireless tag 7a is read. That is, the data of the wireless tag 7c is discarded.

  Next, the data of the wireless tag 8b is read. Then, since the header data D1 of the wireless tag 8b is “00110001”, the mask data M = “11111110” is selected from the table memory 23. As a result, the lower 1 bit of the serial number D3 of the wireless tag 8b is masked. Here, the serial number D3 of the data of the wireless tag 8b is either “00000000” or “00000001”. Therefore, the portion other than the masked portion is “0000000”. At this time, the transmission buffer memory 21 stores the data of the wireless tag 7d and the wireless tag 8a. Among them, the wireless tag 8a shares the wireless tag 8b with the header data D1 and the article identification code D2, and differs only in the lower one digit of the serial number D3. Accordingly, data other than the masked portion of the wireless tag 8b is overlapped with data other than the masked portion of the wireless tag 8a by the duplication check process, and therefore the data of the wireless tag 8b is discarded.

  Next, the data of the wireless tag 9a is read. Then, since the header data D1 of the wireless tag 9a is “00110001”, the mask data M = “11111110” is selected from the table memory 23. As a result, the lower 1 bit of the serial number D3 of the wireless tag 9a is masked. Here, the serial number D3 of the wireless tag 9a is either “00000000” or “00000001”. Therefore, the portion other than the masked portion is “0000000”. At this time, the transmission buffer memory 21 stores the data of the wireless tag 7d and the wireless tag 8a. Among them, the wireless tag 8a has the same wireless tag 9a and header data D1. Data other than the masked portion of the serial number D3 also matches. However, the article identification code D2 is different. Therefore, the data of the wireless tag 9a is stored in the transmission buffer memory 21 as it is.

  Next, the data of the wireless tag 9b is read. Then, since the header data D1 of the wireless tag 9b is “00110001”, the mask data M = “11111110” is selected from the table memory 23. As a result, the lower 1 bit of the serial number D3 of the wireless tag 9b is masked. Here, the serial number D3 of the wireless tag 9b is either “00000000” or “00000001”. Therefore, the portion other than the masked portion is “0000000”. At this time, the transmission buffer memory 21 stores data of the wireless tag 7d, the wireless tag 8a, and the wireless tag 9a. Among them, the wireless tag 9a has the same wireless tag 9b as the header data D1 and the article identification code D2, and differs only in the lower one digit of the serial number D3. Accordingly, the data other than the masked portion of the wireless tag 9b and the data other than the masked portion of the wireless tag 9a are overlapped by the duplication check process, so the data of the wireless tag 9b is discarded.

  Finally, the data of the wireless tag 7b is read. Then, since the header data D1 of the wireless tag 7b is “00110010”, the mask data M = “11111100” is selected from the table memory 23. Here, the serial number D3 of the wireless tag 7b is any one of “00000000”, “00000001”, “00000010”, or “00000011”. Therefore, processing is performed in the same manner as when the data of the wireless tag 7a or 7c is read, and the data of the wireless tag 7b is discarded.

  Thus, in the transmission buffer memory 21, the data of the wireless tag 7d, which is one of the four wireless tags 7a to 7d attached to the pallet 5, and the two wireless tags 8a and 8b attached to the product 6a are stored. Data of the wireless tag 8a which is one of them and data of the wireless tag 9a which is one of the two wireless tags 9a and 9b attached to the product 6b are stored. Then, these three RFID tag data are transmitted to the client 2 via the transmission path 3.

  As described above, according to the present embodiment, even when a plurality of wireless tags are attached to one article (pallet 5 or goods 6a, 6b) to realize quick and highly accurate article recognition, it is transmitted to the client 2. The amount of data of the wireless tag data is the same as when only one item is attached to the article. Therefore, the load on the client 2 can be reduced. In addition, there is an effect that the amount of communication traffic between the reader / writer 1 and the client 2 can be reduced.

(Second Embodiment)
Next, a second embodiment relating to the present invention will be described. In the second embodiment, the hardware configuration of the system constructed on the logistics base side of the logistics management system and the wireless tag attached to each attachment object (pallet 5, products 6a, 6b, etc.) The data structure is the same as that in the first embodiment. Therefore, the drawings in FIGS. 1 to 4 are also used in the second embodiment, and the description thereof is omitted.

  In the second embodiment, the control unit 17 of the reader / writer 1 executes the RFID tag data reading process according to the procedure shown in the flowchart of FIG. In FIG. 6, parts that are the same as those in the same process of the first embodiment shown in FIG.

  That is, in the second embodiment, when it is determined that there is no duplication as a result of the duplication check process in ST8 (NO in ST9), among the RFID tag data stored in the pre-mask processing memory 22 as ST14, ST7 The portion masked by the above process is replaced with a fixed value “0” (data replacement means). Thereafter, the wireless tag data in which the mask portion is replaced with the fixed value “0” is added to the transmission buffer memory 21.

  The above points are different from the first embodiment, and the other parts are the same as those of the first embodiment, and thus description thereof is omitted here.

  As described above, in the second embodiment, when it is determined that there is no duplication as a result of the duplication check processing, the RFID tag data in which the masked portion is replaced with the fixed value “0” is added to the transmission buffer memory 21. Like to do.

  Therefore, as in the first embodiment, in FIG. 1, when data is read in the order of the wireless tags 7d, 7a, 8a, 7c, 8b, 9a, 9b, 7b, Each data of the wireless tag 7d, the wireless tag 8a, and the wireless tag 9a is stored. The serial numbers D3 of these wireless tag data are all unified to “00000000”. Here, for example, even if the serial number “00000001” is replaced with “00000000”, the article identification code D2 is not changed, so there is no influence on the article management in the host device using the wireless tag data.

  Therefore, the client 2 that processes the RFID tag data fetched from the reader / writer 1 does not need to identify the serial number 3 of each RFID tag data, so that the load on the client 2 can be further reduced.

  In the second embodiment, the fixed value for replacing the mask portion has been described as “0”, but it goes without saying that values other than “0” may be fixed values.

(Third embodiment)
FIG. 7 is a configuration diagram of a system constructed on the physical distribution base side of the physical distribution management system in the third embodiment. As shown in the figure, the distribution base includes a first wireless tag reader / writer 1A (hereinafter abbreviated as first reader / writer 1A) and a second wireless tag reader / writer 1B (hereinafter referred to as second reader / writer 1B). A relay device 100 and a client computer 200 (hereinafter abbreviated as a client 200). The client 200 functions as a host device of the first reader / writer 1A and the second reader / writer 1B. The first reader / writer 1A, the second reader / writer 1B, and the client 200 are connected via the relay device 100 by transmission cables 3A, 3B, 3C. Although not shown, the client 200 is connected to a server installed at the headquarters or the like of each distribution base via a network.

  The first and second reader / writers 1A and 1B include antennas 4A and 4B, respectively. The antennas 4A and 4B are a loop coil antenna, a dipole antenna, a planar patch antenna, or the like. The antenna 4A and the antenna 4B are arranged to face each other so that at least a part of the mutual communication area overlaps.

  The first reader / writer 1A reads the wireless tag data existing in the communication area of the antenna 4A in a non-contact manner using wireless communication, and relays the read wireless tag data via the transmission path 3A. Transmit to device 100. The second reader / writer 1B reads the wireless tag data existing in the communication area of the antenna 4B in a non-contact manner using wireless communication, and relays the read wireless tag data via the transmission path 3B. Transmit to device 100. At this time, the first and second reader / writers 1A and 1B use a collision prevention function called anti-collision, and when there are a plurality of wireless tags in the communication area, the data of these wireless tags are stored. It can be read continuously.

  The first reader / writer 1A and the second reader / writer 1B together with the relay device 100 function as the wireless tag reader of the present invention. The hardware configuration of the first reader / writer 1A and the second reader / writer 1B is the same as the configuration of FIG. 3 used in the first embodiment. However, the table memory 23 and the flag memory 24 are not formed in the memory 20.

  As shown in FIG. 8, the relay device 100 includes a first interface 101, a second interface 102, a third interface 103, and a control unit 104. The first interface 101 manages data communication between the first reader / writer 1 </ b> A and the control unit 104. The second interface 102 manages data communication between the second reader / writer 1 </ b> B and the control unit 104. The third interface 103 manages data communication between the client 2 and the control unit 104.

  The control unit 104 includes a memory 110. Similar to the reader / writer 1 of the first embodiment, the memory 110 includes storage areas of a transmission buffer memory 21, a pre-mask processing memory 22, a table memory 23, and a flag memory 24.

  The control unit 17 of each of the first reader / writer 1A and the second reader / writer 1B executes the reading process of the RFID tag data according to the procedure shown in the flowchart of FIG. That is, when receiving a tag reading start command via the interface 11, the control unit 17 starts this process.

  First, the control unit 17 gives tag inquiry command data to the modulation unit 12 as ST21 to control the transmission of the tag inquiry command, and waits for the response of the wireless tag data as ST22. Each time the wireless tag data demodulated by the demodulator 15 is fetched, the processing after ST23 is executed.

  In ST23, the wireless tag data demodulated by the demodulator 15 is overwritten in the pre-mask processing memory 22. Subsequently, the control part 17 performs a duplication check process as ST24. That is, the transmission buffer memory 21 is searched with the wireless tag data stored in the pre-mask processing memory 22 to determine whether or not the same data is already stored in the transmission buffer memory 21. As a result of the duplication check process, when it is determined that the data is not stored (NO in ST25), the control unit 17 adds the wireless tag data stored in the pre-mask process memory 22 to the transmission buffer memory 21 as ST26. To do. On the other hand, when it is determined that the data is stored (YES in ST25), the control unit 17 discards the wireless tag data in the pre-mask processing memory 22 as ST27.

  The control unit 17 executes the processes of ST23 to ST27 each time it receives the wireless tag data from the demodulation unit 15 in ST22. Then, when a predetermined time has passed without receiving the RFID tag data, the control unit 17 considers that reading of the RFID tag data has been completed in ST28. In this case, the control unit 17 sequentially transmits the wireless tag data stored in the transmission buffer memory 21 as ST29 to the relay device 100, and ends the current reading process.

  The control unit 104 of the relay apparatus 100 executes the relay process of the wireless tag data according to the procedure shown in the flowchart of FIG. That is, when receiving a tag reading start command from the client 200 via the third interface 103, the control unit 104 starts this processing.

  First, in step ST31, the control unit 104 transmits a tag inquiry command to the first reader / writer 1A and the second reader / writer 1B via transmission paths 3A and 3B, respectively. In ST32, it waits for the wireless tag data to be sent from the first reader / writer 1A and the second reader / writer 1B. Each time the wireless tag data is received from either one of the reader / writers 1A and 1B, the control unit 104 executes the processing after ST33.

  In ST33, the wireless tag data received via the first interface 101 or the second interface 102 is overwritten in the pre-mask processing memory 22. Next, the control unit 104 checks the flag memory 24 as ST34. Here, if the mask designation flag F of the flag memory 24 has been reset, the mask process is not executed, and the process proceeds to the process of ST38 to be described later.

  On the other hand, when the mask designation flag F is set, the control unit 104 executes a mask process. Specifically, the header data D1 is read from the wireless tag data stored in the pre-mask processing memory 22 as ST35. Then, the table memory 23 is searched as ST36, and the mask data M set corresponding to the header data D1 is acquired. Next, the control unit 104 reads the serial number D3 from the wireless tag data stored in the pre-mask processing memory 22 as ST37. Then, a mask process is performed on a part of the serial number D3 by calculating a logical product for each bit of the serial number D3 and the mask data M acquired in the process of ST36 (mask processing means). Thereafter, control unit 104 proceeds to the process of ST38.

  In ST38, control unit 104 executes duplication check processing. That is, if the mask designation flag F has been reset in ST34, the transmission buffer memory 21 is searched with the wireless tag data stored in the pre-mask processing memory 22, and the same data is already stored in the transmission buffer memory 21. It is determined whether it is stored. On the other hand, if the mask designation flag F is set, the transmission buffer memory 21 is searched for the RFID tag data masked in ST37, and the same data in the unmasked portion is stored in the transmission buffer memory 21. It is determined whether it has already been stored (duplication determination means).

  As a result of the duplication check process, when it is determined that the data is not stored (NO in ST39), the control unit 104 adds the wireless tag data stored in the pre-mask process memory 22 to the transmission buffer memory 21 as ST40. To do. On the other hand, when it is determined that the data is stored (YES in ST39), the control unit 104 discards the wireless tag data in the pre-mask processing memory 22 as ST41 (duplicate processing means).

  Control unit 104 executes the processes of ST33 to ST41 each time it receives the wireless tag data in ST32. Then, when a certain time has elapsed without receiving the wireless tag data, the control unit 104 regards that the reading of the wireless tag data has been completed as ST42. The predetermined time is sufficiently longer than the time when the control unit 17 of the reader / writer 1A, 1B determines that the reading is finished. If it is determined that the reading is completed, the control unit 104 transmits the wireless tag data stored in the transmission buffer memory 21 as ST43 to the client 2 (tag data transmission unit), and ends the current relay process.

  Now, the pallet 5 and the products 6a and 6b shown in FIG. 1 are placed between the first antenna 4A and the second antenna 4B, which are arranged to face each other, and a wireless tag reading command is transmitted from the client 200, so that the first reader It is assumed that the wireless tags 7a, 7c, 7d, 8a, and 8b are read by the writer 1A, and the wireless tags 7a, 7b, 7c, 9a, and 9b are read by the second reader / writer 1B.

  In this case, the data of each of the wireless tags 7a, 7c, 7d, 8a, and 8b is transmitted from the first reader / writer 1A to the relay device 100. Similarly, the wireless tags 7a, 7b, 7c, 9a, and 9b are transmitted from the second reader / writer 1B to the relay device 100.

  If the mask designation flag F is reset to “0”, the data of the wireless tags 7a and 7c are read by both the first reader / writer 1A and the second reader / writer 1B. Therefore, either one is selected and the other is discarded. Therefore, the data of each wireless tag 7a, 7b, 7c, 7d, 8a, 8b, 9a, 9b is transmitted to the client 200.

  On the other hand, when the mask designation flag F is set to “1”, any one of the four wireless tags 7a, 7b, 7c, and 7d attached to the pallet 5 is masked by the mask processing according to the present invention. Selected, others are discarded. One of the two wireless tags 8a and 8b attached to the product 6a is selected, and the other is discarded. Similarly, one of the two wireless tags 9a and 9b attached to the product 6b is selected and the other is discarded. Therefore, the client 200 includes one of the four wireless tags 7a, 7b, 7c, and 7d attached to the pallet 5, one of the two wireless tags 8a and 8b attached to the product 6a, and the product. A total of three data of one of the two wireless tags 9a and 9b attached to 6b are transmitted. Therefore, the same effect as the first embodiment can be obtained.

  In the third embodiment, the mask portion of the masked RFID tag data may be replaced with a fixed value and transmitted to the client 200 as in the second embodiment. .

  Note that the present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the constituent elements without departing from the spirit of the invention in the implementation stage.

  For example, in each of the above embodiments, the portion masked with the mask data M is the serial number D3 of the RFID tag data, but the portion to be masked is not limited to this. If a portion other than the masks of a plurality of wireless tags attached to the same object becomes the same by masking a part of the wireless tag data, any portion of the wireless tag data may be masked.

  Moreover, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, the constituent elements over different embodiments may be combined.

The block diagram of the system constructed | assembled in the 1st Embodiment of this invention by the distribution base side of a distribution management system. The schematic diagram for demonstrating the data structure of a radio | wireless tag in the said 1st Embodiment. The block diagram which shows the principal part structure of a reader / writer in the same 1st Embodiment. The schematic diagram which shows the main area | regions formed in the memory of a reader / writer in the said 1st Embodiment. 9 is a flowchart showing a main part processing procedure of a wireless tag reading process executed by a control unit of the reader / writer in the first embodiment. 9 is a flowchart showing a main part processing procedure of a wireless tag reading process executed by a control unit of a reader / writer in the second embodiment of the present invention. The block diagram of the system constructed | assembled in the 3rd Embodiment of this invention on the distribution base side of a distribution management system. The block diagram which shows the principal part structure of a relay apparatus in the said 3rd Embodiment. 9 is a flowchart showing a main part processing procedure of a wireless tag reading process executed by a control unit of a reader / writer in the third embodiment. The flowchart which shows the principal process procedure of the data relay process which the control part of a relay apparatus performs in the same 3rd Embodiment.

Explanation of symbols

  1, 1A, 1B: RFID tag reader / writer (reader / writer), 2,200 ... client, 3, 3A, 3B, 3C ... transmission path, 4, 4A, 4B ... antenna, 5 ... pallet, 6a, 6b ... commodity 7a, 7b, 7c, 7d, 8a, 8b, 9a, 9b ... wireless tag, 17, 104 ... control unit, 21 ... transmission buffer memory, 22 ... pre-mask processing memory, 23 ... table memory, 24 ... flag memory, 100: Relay device.

Claims (8)

In a wireless tag reader that reads data of a plurality of wireless tags by a tag reader and transmits the data to a host device,
Mask processing means for masking a part of each of the data of the plurality of wireless tags read by the tag reading means,
For each of the data of a plurality of wireless tags read by the tag reading means, duplication determination means for judging whether or not other than the portion masked by the mask processing means,
When there are a plurality of RFID tag data other than the portion masked by the duplication determination unit, a duplication processing unit that selects one of them and discards the rest,
Tag data transmission means for transmitting the RFID tag data selected by the duplication processing means to the host device;
A wireless tag reading apparatus comprising: The wireless tag data selected by the duplication processing means further comprises a data replacement means for replacing the portion masked by the mask processing means with a fixed value,
2. The wireless tag reader according to claim 1, wherein the tag data transmission means transmits the wireless tag data replaced by the data replacement means to the host device. A table that stores different mask data corresponding to the data for identifying the classification of the wireless tag data, and
The mask processing means identifies the classification of each of the plurality of RFID tag data read by the tag reading means from the RFID tag data, and reads out and masks the mask data corresponding to the classification from the table. The wireless tag reader according to claim 1 or 2. A plurality of tag readers each for reading data of a plurality of wireless tags, and a relay unit connected to each tag reader via communication means,
The relay unit is
Mask processing means for masking a part of each of the data of a plurality of wireless tags read by each tag reader,
For each of the data of a plurality of wireless tags read by each tag reader, duplication determination means for determining whether or not there is duplication other than the portion masked by the mask processing means,
When there are a plurality of RFID tag data other than the portion masked by the duplication determination unit, a duplication processing unit that selects one of them and discards the rest,
Tag data transmission means for transmitting the RFID tag data selected by the duplication processing means to the host device;
A wireless tag reading apparatus comprising: The wireless tag data selected by the duplication processing means further comprises a data replacement means for replacing the portion masked by the mask processing means with a fixed value,
5. The wireless tag reader according to claim 4, wherein the tag data transmitting means transmits the wireless tag data replaced by the data replacing means to a host device. The relay unit further includes a table storing different mask data corresponding to data for identifying the classification of the RFID tag data;
The mask processing means identifies the classification of each of the plurality of RFID tag data read by the tag reading means from the RFID tag data, and reads out and masks the mask data corresponding to the classification from the table. The wireless tag reader according to claim 4 or 5. A tag reading step for reading data of a plurality of wireless tags by wireless communication;
A mask processing step for masking a part of each of the data of the plurality of wireless tags read by the tag reading step,
For each of the data of the plurality of wireless tags read by the tag reading step, a duplication determination step for judging whether or not there is duplication other than the portion masked by the mask processing step;
When there are a plurality of wireless tag data other than the portion masked by this duplication determination step, a duplication processing step of selecting one of them and discarding the rest,
A tag data transmission step for transmitting the RFID tag data selected in this duplication processing step to the host device;
A wireless tag reading method comprising: A data replacement step for replacing the portion masked by the mask processing means with a fixed value for the RFID tag data selected by the duplication processing step,
8. The wireless tag reading method according to claim 7, wherein the tag data transmission step transmits the wireless tag data replaced in the data replacement step to a host device.

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