Wireless tag reader and program

Abstract

To provide a wireless tag reading apparatus and a program capable of performing notification when there is an external factor affecting the reading of a wireless tag.SOLUTION: A wireless tag reading apparatus comprises: a radio wave transmitting / receiving section that transmits a radio wave and receives a response wave from a wireless tag to the radio wave; a signal acquisition section that acquires, as a time series signal, the response wave received by the radio wave transmitting / receiving section moving with time; an information acquisition section that acquires information included in the response wave and registered in the wireless tag on condition that it is determined that the time series signal acquired by the signal acquisition section is the response wave from the wireless tag attached to an article housed in a housing section placed at a predetermined position; an environment recognition section that detects at least movement of the housing section or the article; and a notification section that performs notification on condition that the environment recognition section detects at least the movement of the housing section or the article while the radio wave transmitting / receiving section transmits the radio wave.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] An embodiment of the present invention relates to a wireless tag reader and a program. [Background technology]

[0002] BACKGROUND ART Conventionally, there has been known a wireless tag reader that reads information from a wireless tag attached to an item contained in a basket (for example, Patent Document 1).

[0003] Such wireless tag readers have the problem that if the product or the basket containing the product is moved while reading the wireless tag attached to the product, the correct information cannot be read. Also, if a person moves around the wireless tag reader, the radio wave environment changes, which can affect the results of reading the wireless tag. Summary of the Invention [Problem to be solved by the invention]

[0004] The problem to be solved by the present invention is to provide a radio tag reader and a program that can notify the user when there is an external factor that affects the reading of a radio tag. [Means for solving the problem]

[0005] The RFID tag reading device of the embodiment includes a radio wave transmitting / receiving unit, a movement control unit, a signal acquiring unit, a determination unit, an information acquiring unit, an environment recognition unit, and a notification unit. The radio wave transmitting / receiving unit transmits radio waves and receives response waves from the RFID tag in response to the radio waves. The movement control unit moves the position of the radio wave transmitting / receiving unit over time. The signal acquiring unit acquires the response waves received by the radio wave transmitting / receiving unit moved by the movement control unit as a time-series signal. The determination unit determines whether the time-series signal acquired by the signal acquiring unit is a response wave from a RFID tag attached to an item stored in a storage unit placed at a predetermined position. The information acquiring unit acquires information registered in the RFID tag that is included in the response wave, on the condition that the determination unit determines that the time-series signal acquired by the signal acquiring unit is a response wave from a RFID tag attached to an item stored in a storage unit placed at a predetermined position. The environment recognition unit detects at least the movement of the storage unit or the movement of the item. The notification unit issues a notification on the condition that the environment recognition unit detects at least movement of the storage unit or movement of the article while the radio wave transmitting / receiving unit is transmitting radio waves. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a perspective view showing an example of an external appearance of a wireless tag reading device according to an embodiment. [Figure 2] FIG. 2 is a top view showing an example of a main configuration around the antenna of the wireless tag reader according to the embodiment. [Figure 3] FIG. 3 is a hardware block diagram showing an example of the hardware configuration of the wireless tag reading device according to the embodiment. [Figure 4] FIG. 4 is a diagram showing an example of information that the wireless tag reader acquires from the RFID tag. [Figure 5A] FIG. 5A is a top view and a side view showing an example of how the wireless tag reader reads information from an RFID tag attached to an item in a basket. [Figure 5B] FIG. 5B is a diagram illustrating the RSSI value and the phase value. [Figure 6]FIG. 6 is a diagram illustrating a method for determining whether an RFID tag is inside or outside a basket. [Figure 7] FIG. 7 is a diagram illustrating a method for recognizing whether or not there is any movement of a basket, product, or person from an image captured by a surveillance camera. [Figure 8] FIG. 8 is a diagram illustrating an example of a notification method performed by the wireless tag reading device according to the embodiment. [Figure 9] FIG. 9 is a functional block diagram illustrating an example of a functional configuration of the wireless tag reading device according to the embodiment. [Figure 10] FIG. 10 is a flowchart showing an example of the flow of processing performed by the wireless tag reading device according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0007] An embodiment in which the present invention is applied to a radio tag reader 10 will be described with reference to the drawings.

[0008] (General configuration of a wireless tag reader) The schematic configuration of a radio tag reader 10 will be described with reference to Figures 1 and 2. Figure 1 is an external perspective view showing an example of a radio tag reader according to an embodiment. Figure 2 is a top view showing an example of a main configuration around an antenna of the radio tag reader according to an embodiment.

[0009] The RFID tag reader 10 is installed, for example, at a self-checkout register. As shown in FIG. 1 , the RFID tag reader 10 moves a pair of antennas 14 and 15 installed on a moving stage 18 along the Y axis below a basket 13 placed on a table 12 and containing a product 22 purchased by a customer. The pair of antennas 14 and 15 are installed below the table 12 along the X axis. The pair of antennas 14 and 15 are installed tilted relative to each other around the Y axis toward the position where the basket 13 will be placed. The basket 13 is placed at a predetermined position on the table 12, for example, inside a placement position marker 16 attached to the table 12. A plurality of products 22 are stored in the basket 13. The basket 13 is an example of a storage section in the present disclosure. The product 22 is an example of an article in the present disclosure. The product 22 may also be placed directly inside the placement position marker 16 on the table 12. That is, the basket 13 may not be necessary.

[0010] As shown in FIG. 2, the moving stage 18 moves in the Y-axis direction, ie, the direction of arrow A, along rails 21 by the rotational driving force of a driving motor 20 .

[0011] The antennas 14 and 15 transmit radio waves (transmission waves) for reading information (tag information) registered in the RFID tag 24 attached to the product 22 in a time-division manner while moving in the Y-axis direction. The antennas 14 and 15 also receive radio waves (response waves) from the RFID tag 24. The wireless tag reading device 10 repeatedly transmits and receives such radio waves at predetermined time intervals.

[0012] Since the RFID tag 24 has directionality, the wireless tag reader 10 is provided with two antennas 14, 15 and sends transmission waves from different directions, thereby being able to reliably detect the response waves from the RFID tag 24 regardless of the arrangement of the RFID tag 24 inside the cage 13. The number of antennas is not limited to two.

[0013] The RFID (Radio Frequency IDentification) tag 24 is an example of a wireless tag in the present disclosure. The RFID tag 24 is equipped with an antenna and receives transmission waves transmitted from the antennas 14 and 15 via short-range wireless communication. The RFID tag 24 also transmits information stored in a storage medium of the RFID tag 24 as a response wave to the transmission waves. The RFID tag 24 stores tag information in the storage medium. The tag information is, for example, a product code (e.g., an EPC (Electronic Product Code)) that can identify the product 22 to which the RFID tag 24 is attached. When the RFID tag 24 receives radio waves from the antennas 14 and 15 to read out information stored in the storage medium, it transmits the product code and the like stored in the storage medium.

[0014] As shown in Fig. 1, a surveillance camera 26 is installed above the platform 12, facing the platform 12. The surveillance camera 26 monitors the platform 12 and its surrounding area, for example, the range of the angle of view ω in Fig. 1. The wireless tag reader 10 analyzes the video captured by the surveillance camera 26 while the antennas 14 and 15 are moving, and determines whether the basket 13, the product 22, or a person is moving. This will be described in more detail later. The surveillance camera 26 is an example of an imaging unit in the present disclosure.

[0015] The radio tag reader 10 may be provided with a shield on the mounting base 12 that blocks radio waves and surrounds the basket 13 in order to prevent the radio wave environment from being disturbed by external foreign objects.

[0016] (Hardware configuration of wireless tag reader) The hardware configuration of the wireless tag reader 10 will be described with reference to Fig. 3. Fig. 3 is a hardware block diagram showing an example of the hardware configuration of the wireless tag reader of the embodiment.

[0017] The RFID tag reader 10 includes a control unit 31 for controlling each unit of the RFID tag reader 10. The control unit 31 includes a CPU (Central Processing Unit) 32, a ROM (Read Only Memory) 33, and a RAM (Random Access Memory) 34. The CPU 32 is connected to the ROM 33 and the RAM 34 via an internal bus 35 such as an address bus and a data bus. The CPU 32 loads various programs stored in the ROM 33 and the storage unit 36 ​​into the RAM 34. The CPU 32 controls the operation of the RFID tag reader 10 by operating in accordance with the various programs loaded into the RAM 34. In other words, the control unit 31 has the configuration of a typical computer.

[0018] The control unit 31 is connected to a storage unit 36 ​​, a transmission / reception controller 37 , a motor driver 38 , a camera driver 39 , a display device 40 , an operation device 41 , and a communication interface 42 via an internal bus 35 .

[0019] The control unit 31 functions as a reader that reads information registered in the RFID tag 24 by working in cooperation with the transmission / reception controller 37, the antenna 14, and the antenna 15. The control unit 31 may also function as a writer that writes information to the RFID tag 24.

[0020] The control unit 31 acquires information for identifying the antennas 14 and 15, the time when the reply wave was received, the EPC read from the RFID tag 24, the RSSI value, and the phase value in association with each other. The RSSI value (Received Signal Strength Indicator) is a value that represents the strength of the reply wave returning from the RFID tag 24. The phase value is a value that represents the phase difference between the transmitted wave and the reply wave returning from the RFID tag 24. Based on the phase value, the distance between the antenna 14 and the RFID tag 24 or the distance between the antenna 15 and the RFID tag 24 can be estimated. The RSSI value and the phase value will be described in detail later (see FIG. 5B).

[0021] The storage unit 36 ​​is a storage device equipped with a non-volatile storage medium such as a hard disk drive (HDD) or a solid state drive (SSD), etc. The storage unit 36 ​​stores various programs and various data related to the operation of the RFID tag reading device 10.

[0022] The storage unit 36 ​​stores a control program P, read data D, a tag position estimation model Ma, an object recognition model Mb, and a skeleton model Mc.

[0023] The control program P is a program for operating the RFID tag reader 10.

[0024] The read data D is time-series data obtained from the RFID tag 24 while the antennas 14 and 15 are moving. The contents of the read data D will be described in detail later (see FIG. 4).

[0025] The tag position estimation model Ma is a learning model that estimates the location of an RFID tag 24 that has received a response wave. The tag position estimation model Ma is a model that has been trained to output the location of the RFID tag 24 in response to the input of a response wave from the RFID tag 24 by placing an RFID tag 24, in which known data has been registered, at a plurality of predetermined positions and storing the results of reading the response wave with the RFID tag reader 10. More specifically, the tag position estimation model Ma is generated based on the RSSI value and phase value of the response wave from the RFID tag 24. The tag position estimation model Ma will be described in detail later (see FIG. 6).

[0026] The object recognition model Mb is a model for recognizing the product 22 and the basket 13 from the image captured by the monitoring camera 26.

[0027] The skeleton model Mc is a model representing a human skeleton for detecting a human being from an image captured by the surveillance camera 26.

[0028] The transmission / reception controller 37 transmits and receives radio waves between the control unit 31 and the antennas 14 and 15 .

[0029] The motor driver 38 is a controller for the drive motor 20 that drives the moving stage 18. The motor driver 38 controls the drive motor 20 in accordance with the movement instructions for the antennas 14 and 15 output by the control unit 31.

[0030] The camera driver 39 receives instructions from the control unit 31 and controls the imaging operation of the monitoring camera 26 .

[0031] The display device 40 displays a screen generated in response to an instruction from the control unit 31. The display device 40 is configured with a device such as an LCD (Liquid Crystal Display) or an organic EL (Electro-Luminescence) display. The display device 40 is an example of a display unit in the present disclosure.

[0032] The operation device 41 acquires an input operation from an operator and transmits it to the control unit 31. The operation device 41 is configured with devices such as a touch panel and a keyboard, for example.

[0033] The communication interface 42 is an interface for communicating with external devices such as a POS terminal and a store server (not shown) via a network, etc. The wireless tag reading device 10 outputs the reading result of the RFID 24 to these external devices.

[0034] (Explanation of information acquired by wireless tag readers) The contents of the read data D that the wireless tag reader 10 acquires from the RFID tag 24 will be described with reference to Fig. 4. Fig. 4 is a diagram showing an example of information that the wireless tag reader acquires from the RFID tag.

[0035] The read data D is stored by associating antenna identification information Da, time information Db, EPC (Dc), RSSI value Dd, and phase value De.

[0036] The antenna identification information Da is information for identifying whether the information is received by the antenna 14 or the information is received by the antenna 15.

[0037] The time information Db is information indicating the time when the response wave from the RFID tag 24 is received. The time information Db is measured by the control unit 31. Instead of the time information Db, position information indicating the position of the antenna 14 or the position of the antenna 15 when the response wave from the RFID tag 24 is received may be stored. The positions of the antennas 14, 15 are identified, for example, by detecting that the moving stage 18, which is located at a predetermined home position, has moved in a direction defined by the rotation direction of the drive motor 20 by the number of rotations of the drive motor 20.

[0038] The EPC(Dc) is a product code that can identify the product 22. The EPC(Dc) is, for example, a JAN code.

[0039] The RSSI value Dd is a value that indicates the strength of the response wave returning from the RFID tag 24 .

[0040] The phase value De represents the phase difference between the transmitted wave and the response wave returning from the RFID tag 24. The phase value De varies between 0° and 359°. When the phase difference between the transmitted wave and the response wave changes from 359° to 360°, the phase value again indicates 0°. Therefore, the phase value acquired by the RFID tag reading device 10 is discontinuous between 359° and 0°. Therefore, the RFID tag reading device 10 performs a process to correct the acquired phase value. Specifically, when the phase value changes from 359° to 0°, the phase value after the change is corrected to 360°. When the phase value changes from 0° to 359°, the phase value after the change is corrected to -1°. As a result, the phase value Df acquired by the RFID tag reading device 10 exhibits a characteristic of continuously changing with time.

[0041] The wireless tag reader 10 performs the reading process of the RFID tag 24 in session 1 (S1), session 2 (S2), or session 3 (S3). Therefore, once the RFID tag 24 has responded, it will not respond again for a predetermined period of time.

[0042] (RSSI and phase values ​​explained) The RSSI value Dd and phase value Df acquired by the wireless tag reader 10 will be described with reference to Figures 5A and 5B. Figure 5A is a top view and a side view showing an example of the wireless tag reader reading information from an RFID tag attached to an item in a basket. Figure 5B is a diagram for explaining the RSSI value and the phase value.

[0043] 5A, the wireless tag reading device 10 transmits radio waves from the antennas 14 and 15 to the basket 13 in a time-sharing manner while moving the antennas 14 and 15 along the Y axis below the basket 13 placed in a fixed position. Then, the antennas 14 and 15 receive response waves from the RFID tags 24 attached to the products 22 in response to the transmission waves transmitted by the antennas 14 and 15.

[0044] Since the transmission of radio waves and the reception of reply waves are performed at predetermined time intervals while the antennas 14 and 15 are moving, the RFID tag reader 10 acquires time-series data of RSSI values ​​and phase values ​​shown in FIG. 5B.

[0045] 5B indicates the time t at which the response wave is acquired by the RFID tag reader 10. The horizontal axis of FIG. 5B may also be considered to indicate the positions of the antennas 14 and 15 in the Y-axis direction.

[0046] The time-series data of the RSSI value indicates a larger value when the antenna 14 or 15 is located closer to the RFID tag 24 that returned the response wave. Also, the time-series data of the RSSI value indicates a smaller value when the antenna 14 or 15 is located farther from the RFID tag 24 that returned the response wave. Therefore, as shown in FIG. 5B, the RSSI value indicates a larger value when the antenna 14 or 15 is located closer to the cage 13.

[0047] The time-series data of the phase values ​​indicates values ​​according to the distance between the antenna 14 or 15 and the RFID tag 24 that returned the reply wave. Fig. 5B shows an example in which the phase value increases as the distance between the antenna 14 or 15 and the RFID tag 24 that returned the reply wave decreases. Note that the phase values ​​shown in Fig. 5B indicate the results of correcting the discontinuously changing phase values ​​so that they change continuously.

[0048] (Explanation of how to estimate the location of an RFID tag) A method in which the wireless tag reader 10 estimates the position of the RFID tag 24 will be described with reference to Fig. 6. Fig. 6 is a diagram illustrating a method for determining whether the RFID tag is inside or outside the basket.

[0049] The time-series change patterns of the RSSI values ​​and phase values ​​acquired by the wireless tag reading device 10 (see FIG. 5B) correspond approximately one-to-one to the positions of the RFID tags 24. FIG. 6 shows an overview of the time-series change patterns of the RSSI values ​​and phase values ​​acquired by the wireless tag reading device 10 when the same RFID tag 24 is placed at multiple positions inside and outside the basket 13.

[0050] When a product 22 with an RFID tag 24 attached is inside the basket 13, the time series change patterns of the RSSI value and phase value acquired by the RFID tag reading device 10 exhibit characteristics with sharp peaks for both the RSSI value and the phase value, as shown in Figure 5B.

[0051] Assume that a product 221 with an RFID tag 24 attached is located outside the basket 13 at the same position as the product 22 in the X-axis direction, but offset in the Y-axis direction to the negative side. In this case, the time-series change pattern of the RSSI value and phase value acquired by the RFID tag reader 10 exhibits a characteristic in which both the RSSI value and the phase value monotonically decrease as the antennas 14 and 15 move in the positive direction of the Y-axis. In this case, no peaks occur in the RSSI value and the phase value.

[0052] Assume that a product 222 with an RFID tag 24 is located outside the basket 13 at the same position as the product 22 in the X-axis direction, but offset in the Y-axis direction to the positive side. In this case, the time-series change pattern of the RSSI value and phase value acquired by the RFID tag reader 10 exhibits a characteristic in which both the RSSI value and the phase value monotonically increase as the antennas 14 and 15 move in the Y-axis positive direction. In this case, no peaks occur in the RSSI value and the phase value.

[0053] Assume that a product 223 with an RFID tag 24 attached is located outside the basket 13, at the same position in the Y-axis direction as the product 22, but offset in the X-axis direction to the negative side. In this case, the time-series change pattern of the RSSI value and phase value acquired by the RFID tag reading device 10 has peaks in both the RSSI value and the phase value, but the peaks that occur are gentler than when the RFID tag 24 is inside the basket 13.

[0054] In this way, the time-series change patterns of the RSSI values ​​and phase values ​​acquired by the RFID tag reading device 10 correspond approximately one-to-one to the positions of the RFID tags 24. The tag position estimation model Ma stored in the RFID tag reading device 10 is a model in which the time-series change patterns of the RSSI values ​​and phase values ​​acquired from each of the RFID tags 24 placed at a plurality of known positions are stored in association with the positions of the RFID tags 24. The tag position estimation model Ma is trained so as to output the estimated position of the RFID tag 24 when the time-series change patterns of the RSSI values ​​and phase values ​​are input.

[0055] (Explanation of how to detect the movement of baskets, products, and people) A method by which the wireless tag reading device 10 detects the movements of the basket 13, the product 22, and the person 60 will be described with reference to Fig. 7. Fig. 7 is a diagram illustrating a method for recognizing whether there is any movement of the basket, the product, or the person from the video captured by the surveillance camera.

[0056] The surveillance camera 26 captures a surveillance image I(t) shown in Fig. 7 at predetermined time intervals at least while the wireless tag reading device 10 is transmitting radio waves. The surveillance image I(t) shows a person 60 who is shopping and is near the basket 13, the stand 12, the basket 13, and the product 22.

[0057] The RFID tag reader 10 extracts the person 60, the basket 13, and the commodity 22 from the monitoring image I(t) by performing predetermined image processing on the monitoring image I(t).

[0058] The RFID tag reader 10 detects a person 60 in the surveillance image I(t) by using, for example, a skeleton detection method using well-known deep learning. Next, the posture of the person detected in the person detection process is estimated by utilizing a technique called posture estimation, which detects a person's skeleton data. The estimated posture of the person 60 is recognized as a skeleton 62 shown in FIG. 7. The RFID tag reader 10 tracks the detected person 60 in the surveillance image I(t) captured at a predetermined time interval. In this way, the RFID tag reader 10 determines whether the detected person 60 is moving. In particular, if a movement such as moving a hand held over the mounting table 12 is detected, the RFID tag reader 10 issues an alert because this may affect the reading result of the RFID tag 24.

[0059] The tracking process of the person 60 can be realized by, for example, performing image classification using deep learning. Specifically, at least one feature of the person 60 is extracted by using, for example, a convolutional layer of a convolutional neural network (CNN) as a feature extractor. Then, by comparing the features extracted from different surveillance images I(t) with each other using a nearest neighbor method or the like, it is possible to determine whether or not they represent the same person, and track the same person.

[0060] The wireless tag reading device 10 also detects the basket 13 from within the monitoring image I(t). Because the shape and size of the basket 13 when viewed from directly above are fixed, the wireless tag reading device 10 performs a process of detecting an area of ​​a known shape and size from within the monitoring image I(t). Alternatively, the basket 13 may be detected by performing template matching using an image of the basket 13 viewed from directly above as a template. A basket position 61 may be drawn at the position of the detected basket 13, for example, as shown in FIG. 7.

[0061] The wireless tag reader 10 tracks the detected basket 13 in the monitoring image I(t) captured at a predetermined time interval. The tracking process can be performed in the same way as the tracking of the person 60 described above. In this way, the wireless tag reader 10 determines whether the detected basket 13 is moving. If it is detected that the basket 13 is moving, the wireless tag reader 10 issues an alert because this may affect the reading result of the RFID tag 24.

[0062] The RFID tag reader 10 also detects the product 22 by performing, for example, object recognition on the surveillance image I(t). Furthermore, the RFID tag reader 10 tracks the detected product 22 on the surveillance image I(t) captured at predetermined time intervals. The tracking process can be performed in the same manner as the tracking of the person 60 described above. This allows the RFID tag reader 10 to determine whether the detected product 22 is moving. For example, by working in conjunction with the posture estimation described above, it is also possible to detect a state in which the person 60 is holding and moving a product 65 with his or her right hand 63 and left hand 64.

[0063] The RFID tag reading device 10 may include a distance measurement sensor (not shown) in addition to the surveillance camera 26. The distance measurement sensor is, for example, a TOF (Time Of Flight) sensor. The RFID tag reading device 10 may recognize the movement of the basket 13, the product 22, or the person 60 by using distance information acquired by the distance measurement sensor in addition to the surveillance image I(t). The distance measurement sensor is an example of a distance measurement unit in the present disclosure.

[0064] Furthermore, the movement of the basket 13 may be detected by, for example, incorporating a weight sensor in the mounting base 12 and monitoring fluctuations in the output of the weight sensor. That is, if the output of the weight sensor fluctuates while the wireless tag reading device 10 is transmitting radio waves, it may be determined that the basket 13 has moved.

[0065] If the basket 13, product 22, or person 60 moves while the wireless tag reader 10 is reading the RFID tag 24, the RSSI value Dd and phase value De acquired from the RFID tag 24 by the wireless tag reader 10 will fluctuate, and there is a possibility that the location of the RFID tag 24 cannot be accurately estimated. Therefore, the wireless tag reader 10 issues an alert if the basket 13, product 22, or person 60 moves while the wireless tag reader 10 is reading the RFID tag 24.

[0066] (Method of notifying movement of baskets, products, or people) 8, a method of notification performed when the movement of the basket 13, the product 22, or the person 60 is detected while the wireless tag reading device 10 is reading the RFID tag 24 will be described. Fig. 8 is a diagram showing an example of a method of notification performed by the wireless tag reading device of the embodiment.

[0067] When the wireless tag reader 10 detects movement of the basket 13, the product 22, or the person 60 while reading the RFID tag 24, the wireless tag reader 10 displays a warning screen 70 on the display device 40 (see FIG. 3).

[0068] The warning screen 70 includes a message 71 and a reread button 72. The message 71 is a message notifying that movement of the basket 13, the product 22, or the person 60 has been detected while reading the RFID tag 24. The reread button 72 is a button for instructing the wireless tag reading device 10 to reread the RFID tag 24.

[0069] The notification method is not limited to the example shown in Fig. 8. For example, a voice message may be output from a speaker not shown in Fig. 3.

[0070] Also, although not shown in Figure 8, when movement of the basket 13, product 22, or person 60 is detected, the wireless tag reading device 10 may display a message on the warning screen 70 urging the user to re-read the product 22 using another reading device such as a barcode reader.

[0071] In addition, when movement of the basket 13, product 22, or person 60 is detected, the wireless tag reading device 10 may display the identification information acquired by the tag information acquisition unit 55 on the display device 40 on the warning screen 70, allowing the customer to confirm that the read information is correct.

[0072] (Functional configuration of the wireless tag reader) The functional configuration of the wireless tag reading device 10 will be described with reference to Fig. 9. Fig. 9 is a functional block diagram showing an example of the functional configuration of the wireless tag reading device of the embodiment.

[0073] The control unit 31 of the wireless tag reading device 10 deploys the control program P in the RAM 34 and runs it, thereby realizing the tag information reading unit 50, the environment recognition unit 56, and the notification unit 57 shown in Figure 9 as functional units.

[0074] The tag information reading unit 50 irradiates the RFID tag 24 with radio waves and detects the response wave. The tag information reading unit 50 also determines from the detected response wave whether the RFID tag 24 is in a predetermined area (inside the basket 13). The tag information reading unit 50 also acquires information registered in the RFID tag 24 that is contained in the response wave from the RFID tag 24 that is in the predetermined area. The tag information reading unit 50 includes a radio wave transmitting / receiving unit 51, an antenna movement control unit 52, a response wave acquisition unit 53, a tag position determination unit 54, and a tag information acquisition unit 55.

[0075] The radio wave transmitting / receiving unit 51 transmits radio waves and receives response waves from the RFID tag 24 in response to the radio waves.

[0076] The antenna movement control unit 52 moves the position of the radio wave transmitting and receiving unit 51 over time. The antenna movement control unit 52 is an example of a movement control unit in the present disclosure.

[0077] The reply wave acquisition unit 53 acquires, as a time-series signal, the reply wave received by the radio wave transmission / reception unit 51, which is moved by the antenna movement control unit 52. The reply wave acquisition unit 53 is an example of a signal acquisition unit in the present disclosure.

[0078] The tag position determination unit 54 determines whether the time series signal acquired by the response wave acquisition unit 53 is a response wave from the RFID tag 24 attached to the product 22 contained in the basket 13 placed at a predetermined position. The tag position determination unit 54 is an example of a determination unit in the present disclosure.

[0079] The tag information acquisition unit 55 acquires information contained in the response wave and registered in the RFID tag 24, on the condition that the tag position determination unit 54 determines that the time series signal acquired by the response wave acquisition unit 53 is a response wave from the RFID tag 24 attached to the product 22 contained in the basket 13 placed at a predetermined position. The tag information acquisition unit 55 is an example of an information acquisition unit in the present disclosure.

[0080] The environment recognition unit 56 detects at least the movement of the basket 13 or the movement of the product 22 while the radio wave transmitting / receiving unit 51 is transmitting radio waves. The environment recognition unit 56 also detects the movement of a person 60 in the vicinity of the basket 13.

[0081] The notification unit 57 issues a notification on the condition that the environment recognition unit 56 detects at least the movement of the basket 13 or the movement of the product 22 while the radio wave transmitting / receiving unit 51 is transmitting radio waves.

[0082] Furthermore, the notification unit 57 may prompt the customer to re-read the product 22 using a different reading device, provided that the environment recognition unit 56 detects movement of at least the basket 13 or the product 22 while the radio wave transmitting / receiving unit 51 is transmitting radio waves. The different reading device may be, for example, a barcode reader that reads the barcode attached to the product 22. Furthermore, the RFID tag reading device 10 may fix the antennas 14, 15 and re-read the RFID tag 24 attached to the product 22.

[0083] In addition, the alarm unit 57 may display the identification information acquired by the tag information acquisition unit 55 on the display device 40 to prompt the customer to confirm it, provided that the environment recognition unit 56 detects at least the movement of the basket 13 or the movement of the product 22 while the radio wave transmission / reception unit 51 is transmitting radio waves.

[0084] (Processing flow performed by a wireless tag reader) The flow of processing performed by the RFID tag reading device 10 will be described with reference to Fig. 10. Fig. 10 is a flowchart showing an example of the flow of processing performed by the RFID tag reading device of the embodiment.

[0085] First, we will explain the flow of processing performed by the tag information reading unit 50. First, the antenna movement control unit 52 moves the antennas 14 and 15 to the start positions (step S11).

[0086] The radio wave transmitting / receiving unit 51 transmits radio waves from one of the antennas (for example, the antenna 14) (step S12).

[0087] The radio wave transmitting / receiving unit 51 receives the reply wave (step S13).

[0088] The radio wave transmitting / receiving unit 51 transmits radio waves from the other antenna (for example, antenna 15) (step S14).

[0089] The radio wave transmitting / receiving unit 51 receives the reply wave (step S15).

[0090] The reply wave acquisition unit 53 acquires the time at which the reply wave was received, and the EPC, RSSI value, and phase value contained in the reply wave (step S16).

[0091] The antenna movement control unit 52 determines whether the movement of the antennas 14 and 15 is complete (step S17). If it is determined that the movement of the antennas 14 and 15 is complete (step S17: Yes), the process proceeds to step S18. On the other hand, if it is not determined that the movement of the antennas 14 and 15 is complete (step S17: No), the process proceeds to step S19.

[0092] If it is determined in step S17 that the movement of the antennas 14 and 15 has not been completed, the antenna movement control unit 52 moves the antennas 14 and 15 by a predetermined amount (step S19), and then returns to step S12 to repeat the above-described processing.

[0093] On the other hand, if it is determined in step S17 that the movement of antennas 14 and 15 has been completed, antenna movement control unit 52 outputs antenna movement completion information indicating that the movement of antennas 14 and 15 has been completed to environment recognition unit 56 (step S18).

[0094] The tag position determination unit 54 determines whether the RFID tag 24 that returned the response wave is inside the basket 13 based on the RSSI value and the phase value acquired in step S16 (step S20).

[0095] Next, the tag information acquisition unit 55 reads the EPC acquired from the RFID tag 24 determined to be inside the basket 13 in step S20 (step S21).

[0096] Next, the tag information reading unit 50 determines whether movement of the basket 13, the product 22, or the person 60 has been detected while reading (step S22). If it is determined that movement of the basket 13, the product 22, or the person 60 has been detected (step S22: Yes), the process proceeds to step S23. On the other hand, if it is not determined that movement of the basket 13, the product 22, or the person 60 has been detected (step S22: No), the process proceeds to step S24.

[0097] If it is determined in step S22 that movement of the basket 13, the product 22, or the person 60 has been detected, the tag information reading unit 50 instructs the alarm unit 57 to execute an alarm (step S23). After that, the tag information reading unit 50 ends the processing of FIG. 10.

[0098] On the other hand, if it is determined in step S22 that movement of the basket 13, product 22, or person 60 has not been detected, the tag information acquisition unit 55 confirms the information read in step S21 (step S24). Thereafter, the tag information reading unit 50 ends the processing of Fig. 10. The confirmed reading result is sent to a POS terminal, a higher-level server, or the like, where the product is processed for accounting and settlement.

[0099] Next, the flow of processing performed by the environment recognition unit 56 will be described. First, the environment recognition unit 56 determines whether the radio wave transmitting and receiving unit 51 is transmitting radio waves (step S31). If it is determined that the radio wave transmitting and receiving unit 51 is transmitting radio waves (step S31: Yes), the process proceeds to step S32. On the other hand, if it is not determined that the radio wave transmitting and receiving unit 51 is transmitting radio waves (step S31: No), the process repeats the determination in step S31.

[0100] When it is determined in step S31 that the radio wave transmitting / receiving unit 51 is transmitting radio waves, the environment recognition unit 56 detects the cage 13 from the monitoring image I(t) captured by the monitoring camera 26 (step S32).

[0101] Furthermore, the environment recognition unit 56 detects the product 22 from the monitored image I(t) (step S33).

[0102] Furthermore, the environment recognition unit 56 detects a person 60 from the monitoring image I(t) (step S34).

[0103] The environment recognition unit 56 tracks the cage 13 detected in step S32 from among a plurality of monitoring images I(t) captured over time (step S35).

[0104] Furthermore, the environment recognition unit 56 tracks the product 22 detected in step S33 from among a plurality of monitoring images I(t) captured over time (step S36).

[0105] Furthermore, the environment recognition unit 56 tracks the person 60 detected in step S34 from among the multiple monitoring images I(t) captured over time (step S37).

[0106] The environment recognition unit 56 determines whether movement of the basket 13, the product 22, or the person 60 has been detected based on the tracking results of the basket 13, the product 22, and the person 60 (step S38). If it is determined that movement of the basket 13, the product 22, or the person 60 has been detected (step S38: Yes), the process proceeds to step S39. On the other hand, if it is not determined that movement of the basket 13, the product 22, or the person 60 has been detected (step S38: No), the process proceeds to step S40.

[0107] If it is determined in step S38 that the movement of the basket 13, the product 22, or the person 60 has been detected, the environment recognition unit 56 notifies the tag information reading unit 50 that the movement of the basket 13, the product 22, or the person 60 has been detected (step S39). Thereafter, the environment recognition unit 56 ends the processing of FIG. 10.

[0108] If it is determined in step S38 that movement of the basket 13, the product 22, or the person 60 has not been detected, the environment recognition unit 56 determines whether antenna movement completion information indicating that movement of the antennas 14, 15 has been completed has been acquired from the antenna movement control unit 52 (step S40). If it is determined that antenna movement completion information has been acquired (step S40: Yes), the environment recognition unit 56 ends the processing in Fig. 10. On the other hand, if it is not determined that antenna movement completion information has been acquired (step S40: No), the process returns to step S35 and the above-described processing is repeated.

[0109] Next, the flow of processing performed by the notification unit 57 will be described. First, the notification unit 57 determines whether or not a notification instruction has been received from the tag information reading unit 50 (step S51). If it is determined that a notification instruction has been received from the tag information reading unit 50 (step S51: Yes), the process proceeds to step S52. On the other hand, if it is not determined that a notification instruction has been received from the tag information reading unit 50 (step S51: No), the process proceeds to step S53.

[0110] In step S51, when it is determined that a notification instruction has been received from the tag information reading unit 50, the notification unit 57 performs notification, such as displaying the warning screen 70 shown in Fig. 8 (step S52). After that, the notification unit 57 ends the processing in Fig. 10.

[0111] On the other hand, if it is determined in step S51 that an instruction to notify has not been received from the tag information reading unit 50, the notifying unit 57 determines whether antenna movement completion information indicating that the movement of the antennas 14, 15 has been completed has been acquired from the antenna movement control unit 52 (step S53). If it is determined that the antenna movement completion information has been acquired (step S53: Yes), the notifying unit 57 ends the processing in Fig. 10. On the other hand, if it is not determined that the antenna movement completion information has been acquired (step S53: No), the processing returns to step S51 and the above-described processing is repeated.

[0112] (Effects of the embodiment) As described above, the wireless tag reading device 10 of this embodiment includes a radio wave transmitting / receiving unit 51 that transmits radio waves and receives response waves from the RFID tags 24 (wireless tags) in response to the radio waves, a response wave acquiring unit 53 (signal acquiring unit) that acquires the response waves received by the radio wave transmitting / receiving unit 51 that moves with time as a time-series signal, a tag position determining unit 54 (determining unit) that determines whether the time-series signal acquired by the response wave acquiring unit 53 is a response wave from an RFID tag 24 attached to a commodity 22 (item) contained in a basket 13 (container) placed at a predetermined position, and The system includes a tag information acquisition unit 55 (information acquisition unit) that acquires information included in the response wave and registered in the RFID tag 24 on the condition that the time series signal acquired by the response wave acquisition unit 53 is determined to be a response wave from the RFID tag 24 attached to the product 22 contained in the basket 13 placed at a predetermined position, an environment recognition unit 56 that detects at least the movement of the basket 13 or the product 22, and an alarm unit 57 that issues an alarm on the condition that the environment recognition unit 56 detects the movement of the basket 13 or the product 22 while the radio wave transmission / reception unit 51 is transmitting radio waves. Therefore, an alarm can be issued if there is an external factor that affects the reading of the RFID tag 24. The environment recognition unit 56 may also detect the movement of a person 60 while the radio wave transmission / reception unit 51 is transmitting radio waves.

[0113] Furthermore, in the wireless tag reading device 10 of this embodiment, the time-series signal includes identification information for identifying the product 22 (item) registered in the RFID tag 24 (wireless tag), the RSSI value Dd of the reply wave, and the phase value De of the reply wave. Therefore, information regarding the location of the product 22 can be obtained.

[0114] Furthermore, in the wireless tag reading device 10 of this embodiment, the notification unit 57 further prompts another reading device to read the product 22 (article) again on the condition that the environment recognition unit 56 detects movement of the basket 13 or the product 22 while the radio wave transmitting / receiving unit 51 is transmitting radio waves. Therefore, if the reliability of the reading result is low, it is possible to prompt another reading device to read the product 22 again.

[0115] Furthermore, in the wireless tag reading device 10 of this embodiment, the notification unit 57 further displays the identification information acquired by the tag information acquisition unit 55 (information acquisition unit) on the display device 40 (display unit) to prompt the customer to check it, on the condition that the environment recognition unit 56 detects the movement of the basket 13 or the product 22 while the radio wave transmitting / receiving unit 51 is transmitting radio waves. Therefore, if the reliability of the reading result is low, the customer can be prompted to check it.

[0116] Furthermore, in the RFID tag reading device 10 of this embodiment, the environment recognition unit 56 detects the movement of the basket 13 (storage unit) or the product 22 (item) based on the image captured by the monitoring camera 26 (imaging unit) or the distance information measured by the distance measurement sensor (distance measurement unit). Therefore, the movement of the basket 13 or the product 22 can be easily detected.

[0117] Although the embodiments of the present invention have been described above, these embodiments are merely examples and are not intended to limit the scope of the invention. This novel embodiment can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the inventions and their equivalents as defined in the claims. [Explanation of symbols]

[0118] 10. Radio tag reader 12 Mounting table 13 Basket (storage area) 14,15 Antenna 16 Placement position marker 18 Moving Stage 20 Drive motor 21 Rail 22,221,222,223,65 Goods (goods) 24 RFID tags (wireless tags) 26 Surveillance camera (imaging unit) 40 Display device (display unit) 50 Tag information reading unit 51 Radio wave transmitting and receiving unit 52 Antenna movement control unit (movement control unit) 53 Response wave acquisition unit (signal acquisition unit) 54 Tag position determination unit (determination unit) 55 Tag information acquisition unit (information acquisition unit) 56 Environmental recognition department 57 Information Department 60 people 61 Basket position 70 Warning Screen 71 Messages 72 Reread button D Read data Da Antenna Identification Information Db time information DC EPC Dd RSSI value De phase value Ma tag location estimation model Mb object recognition model Mc skeletal model I(t) Monitoring image [Prior art documents] [Patent documents]

[0119] [Patent Document 1] Patent No. 7007170

Claims

1. a radio wave transmitting / receiving unit that transmits radio waves and receives response waves from the wireless tag in response to the radio waves; a movement control unit that moves the position of the radio wave transmitting and receiving unit over time; a signal acquisition unit that acquires, as a time-series signal, a response wave received by the radio wave transmitting / receiving unit that is moved by the movement control unit; a determination unit that determines whether the time series signal acquired by the signal acquisition unit is a response wave from a wireless tag attached to an item stored in a storage unit placed at a predetermined position; an information acquisition unit that acquires information registered in the wireless tag, which is included in the response wave, on the condition that the determination unit determines that the time series signal acquired by the signal acquisition unit is a response wave from a wireless tag attached to an item stored in a storage unit placed at a predetermined position; an environment recognition unit that detects at least a movement of the storage unit or a movement of the item; and a notification unit that issues a notification when the environment recognition unit detects at least a movement of the storage unit or the item while the radio wave transmitting / receiving unit is transmitting radio waves. Radio tag reader.

2. the time series signal includes identification information for identifying the item registered in the wireless tag, an RSSI value of the reply wave, and a phase of the reply wave; 2. The wireless tag reader according to claim 1.

3. The notification unit further prompts another reader to read the item again, on condition that the environment recognition unit detects a movement of at least the storage unit or the item while the radio wave transmitting / receiving unit is transmitting the radio waves.

2. The wireless tag reader according to claim 1.

4. The notification unit further displays the identification information acquired by the information acquisition unit on a display unit to prompt confirmation, on condition that the environment recognition unit detects movement of at least the storage unit or the item while the radio wave transmission / reception unit is transmitting radio waves.

3. The wireless tag reader according to claim 2.

5. The environment recognition unit detecting movement of the storage unit or movement of the article based on an image captured by an imaging unit or distance information measured by a distance measuring unit; The wireless tag reader according to any one of claims 1 to 4.

6. Computer, a radio wave transmitting / receiving unit that transmits radio waves and receives response waves from the wireless tag in response to the radio waves; a movement control unit that moves the position of the radio wave transmitting and receiving unit over time; a signal acquisition unit that acquires, as a time-series signal, a response wave received by the radio wave transmitting / receiving unit that is moved by the movement control unit; a determination unit that determines whether the time series signal acquired by the signal acquisition unit is a response wave from a wireless tag attached to an item stored in a storage unit placed at a predetermined position; an information acquisition unit that acquires information registered in the wireless tag, which is included in the response wave, on the condition that the determination unit determines that the time series signal acquired by the signal acquisition unit is a response wave from a wireless tag attached to an item stored in a storage unit placed at a predetermined position; an environment recognition unit that detects at least a movement of the storage unit or a movement of the item; a notification unit that issues a notification when the environment recognition unit detects a movement of the storage unit or a movement of the item while the radio wave transmitting / receiving unit is transmitting radio waves; A program that makes it work.

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