Wireless tag communication device and wireless tag communication program

Abstract

The objective is to provide a wireless tag communication device that prevents a decrease in the accuracy of inferring the placement area of ​​wireless tags due to anti-collision. [Solution] The wireless tag communication device according to the embodiment includes an antenna that receives radio waves transmitted from a wireless tag, a relative position changing unit that changes the relative position of the antenna with respect to the wireless tag, a reading unit that reads the tag data of the wireless tag at multiple relative positions of the antenna with respect to the wireless tag based on the radio waves received by the antenna, an inference unit that infers the placement area of ​​the wireless tag from the tag data, and a speed setting unit that sets the speed of change of the relative position of the antenna with respect to the wireless tag.

Description

Technical Field

[0001] Embodiments of the present invention relate to a wireless tag communication device and a wireless tag communication program.

Background Art

[0002] In recent years, the use of wireless tags for accounting processes, inspection processes, etc. has been increasing. In such a system, a wireless tag is attached to an article or a product, and the wireless tag communication device detects the wireless tag and reads information from the wireless tag. When the wireless tag receives irradiation of radio waves from the wireless tag communication device, it transmits radio waves in response. The wireless tag communication device detects the wireless tag and reads information from the wireless tag by radiating radio waves from an antenna and receiving the radio waves transmitted from the wireless tag that responds thereto with the antenna.

[0003] Furthermore, the wireless tag communication device performs radio wave transmission and reception while changing the relative position of the antenna with respect to the wireless tag, and infers the arrangement area of the wireless tag by reading information from the wireless tag at a plurality of relative positions of the antenna with respect to the wireless tag. As a method for inferring the arrangement area of the wireless tag, a method based on a phase difference that is a change in phase, a method using a learned model by machine learning, etc. are known.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] Generally, wireless tag communication employs anti-collision to avoid communication collisions. When there are many items, anti-collision prevents wireless tags from responding simultaneously, resulting in a smaller amount of data being obtained from each wireless tag. This reduces the accuracy of inferring the placement area of ​​the wireless tags.

[0006] The problem that this invention aims to solve is to provide a wireless tag communication device and a wireless tag communication program that prevent a decrease in the accuracy of inferring the placement area of ​​wireless tags due to anti-collision. [Means for solving the problem]

[0007] The wireless tag communication device according to this embodiment includes an antenna, a relative position changing unit, a reading unit, an inference unit, and a speed setting unit. The antenna receives radio waves transmitted from the wireless tag. The relative position changing unit changes the relative position of the antenna with respect to the wireless tag. The reading unit reads the tag data of the wireless tag at multiple relative positions of the antenna with respect to the wireless tag based on the radio waves received by the antenna. The inference unit infers the placement area of ​​the wireless tag from the tag data. The speed setting unit sets the speed at which the relative position of the antenna with respect to the wireless tag changes. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a block diagram showing an example configuration of a wireless tag communication device according to an embodiment. [Figure 2] Figure 2 shows an example of the configuration of the relative position change section shown in Figure 1. [Figure 3] Figure 3 shows another example of the relative position change section shown in Figure 1. [Figure 4] Figure 4 shows another example of the relative position change section shown in Figure 1. [Figure 5] Figure 5 shows the hardware configuration of the computer that makes up the reading unit, inference unit, relative position change unit, and terminal shown in Figure 1. [Figure 6]Figure 6 is a flowchart showing an example of the operation of a wireless tag communication device according to an embodiment. [Figure 7] Figure 7 is a flowchart showing an example of the operation of the speed setting process shown in Figure 6. [Figure 8] Figure 8 shows an example of the user interface screen displayed during the speed setting process shown in Figure 7. [Figure 9] Figure 9 is a flowchart showing another example of the speed setting process shown in Figure 6. [Figure 10] Figure 10 is a flowchart showing yet another example of the speed setting process shown in Figure 6. [Figure 11] Figure 11 is a schematic diagram illustrating an example of a picking operation to which the speed setting process shown in Figure 10 is applied. [Figure 12] Figure 12 is a flowchart showing an example of the operation of the reading process shown in Figure 6. [Figure 13] Figure 13 is a flowchart showing an example of the inference process shown in Figure 6. [Figure 14] Figure 14 is a flowchart showing another example of the inference process shown in Figure 6. [Modes for carrying out the invention]

[0009] The embodiments will be described below with reference to the drawings. For illustrative purposes, some components in the drawings may be omitted or simplified as appropriate.

[0010] (Wireless tag communication device) First, with reference to Figure 1, the wireless tag communication device 10 according to the embodiment will be described. Figure 1 is a block diagram showing an example of the configuration of the wireless tag communication device 10 according to the embodiment.

[0011] The wireless tag communication device 10 reads tag data from the wireless tag 90 attached to the item 80 such as a product, infers the placement area of ​​the wireless tag 90 from the read tag data, and performs processing on each wireless tag 90 in the inferred placement area according to its purpose.

[0012] FIG. 1 shows, for the sake of convenience, one article 80 and one wireless tag 90, but this is not intended to indicate the number of articles 80 and wireless tags 90. The number of articles 80 and wireless tags 90 may be one or plural, and generally, there are often plural. One wireless tag 90 is attached to one article 80.

[0013] The wireless tag communication device 10 includes an antenna 20, a relative position changing unit 30, a reading unit 40, an inference unit 50, a terminal 60, and a speed setting unit 70.

[0014] <K The antenna 20 is a device for communicating with the wireless tag 90. The antenna 20 radiates radio waves. Also, the antenna 20 receives radio waves transmitted from the wireless tag 90 that responds to the radio wave radiation. The antenna 20 converts the radio waves received from the wireless tag 90 into a high-frequency signal and outputs the high-frequency signal to the reading unit 40.

[0015] The relative position changing unit 30 changes the relative position of the antenna 20 with respect to the wireless tag 90. A configuration example of the relative position changing unit 30 will be described later.

[0016] The reading unit 40 controls the antenna 20 and the relative position changing unit 30 to read the tag data of the wireless tag 90 based on the radio waves transmitted from the wireless tag 90 and received by the antenna 20. Specifically, the reading unit 40 reads the tag data of the wireless tag 90 at a plurality of relative positions of the antenna 20 with respect to the wireless tag 90.

[0017] The inference unit 50 infers the placement area of ​​the wireless tag 90 from the tag data of the wireless tag 90 at multiple relative positions of the antenna 20 with respect to the wireless tag 90 read by the reading unit 40. For example, the inference unit 50 infers whether the wireless tag 90 is inside or outside one placement area. The number of placement areas is not limited to one. That is, the inference unit 50 may infer whether the wireless tag 90 is inside or outside each of multiple placement areas. The inference unit 50 performs inference, for example, using a trained model obtained by machine learning, or based on the phase difference of the received radio waves.

[0018] Terminal 60 is a device that serves as an interface with the user (i.e., a user interface). Terminal 60 receives instructions from the user to the wireless tag communication device 10. Terminal 60 also presents the user with the processing results from the wireless tag communication device 10, such as the reading results from the reading unit 40 and the inference results from the inference unit 50.

[0019] Furthermore, terminal 60 processes the reading results from reading unit 40 and the inference results from inference unit 50. In one example, terminal 60 is a cash register terminal for accounting. In another example, terminal 60 is a portable terminal used for picking during inspection. However, terminal 60 is not limited to these examples and may be any terminal that processes the reading results from reading unit 40 and the inference results from inference unit 50 according to its purpose.

[0020] The speed setting unit 70 controls the relative position change unit 30 to set the rate of change of the relative position of the antenna 20 with respect to the wireless tag 90 to an appropriate speed. Here, an appropriate speed is a speed at which a sufficient amount of data can be obtained from a single wireless tag 90 even if the number of responses from wireless tags 90 decreases due to anti-collision. For this reason, the speed setting unit 70 sets the speed lower when there are many wireless tags 90 compared to when there are few wireless tags 90.

[0021] The item 80 is, for example, a product displayed in a store for sale, or a product stored in a warehouse or similar place during distribution before shipment or after delivery. However, the item 80 is not limited to these, and may be any item managed using the wireless tag 90.

[0022] The wireless tag 90 is, for example, an RFID (radio frequency identification) tag. However, it is not limited to this, and the wireless tag 90 may be any other type of wireless tag. For example, the wireless tag 90 is a passive wireless tag that operates using radio waves transmitted from the antenna 20 as an energy source. The wireless tag 90 transmits a signal containing the tag data stored in the wireless tag 90 by performing backscatter modulation on an unmodulated signal. The tag data stored in the wireless tag 90 includes uniquely identifiable identification tag data. For example, the tag data stored in the wireless tag 90 includes an identification code for the item 80 to which the wireless tag 90 is attached.

[0023] (Example of the configuration of the relative position change section) Next, with reference to Figure 2, an example of the configuration of the relative position changing unit 30 will be described. Figure 2 is a diagram showing an example of the configuration of the relative position changing unit 30 of the wireless tag communication device 10.

[0024] In the example configuration of the relative position changing unit 30 shown in Figure 2, the antenna 20 has one antenna 211. The antenna 20 is installed under the table 81 on which the item 80 to which the wireless tag 90 is attached is placed.

[0025] The relative position changing section 30 has a moving mechanism 310 for moving the antenna 211. The moving mechanism 310 is a linear motion mechanism for moving the antenna 211 in a straight line. The moving mechanism 310 has a stage 311, a guide rail 312, and a drive unit 316. The stage 311 holds the antenna 211. The guide rail 312 holds the stage 311 so that it can move in a straight line. The guide rail 312 has a ball screw 313 inside. The ball screw 313 has a rotatable screw shaft 314 and a nut 315 that can move along the screw shaft 314 as the screw shaft 314 rotates. The nut 315 holds the stage 311. The drive unit 316 rotates the screw shaft 314. The rotational motion of the screw shaft 314 is converted into the linear motion of the nut 315. Therefore, by rotating the screw shaft 314 with the drive unit 316, the antenna 211 held on the stage 311 is moved in a straight line.

[0026] The drive unit 316 is controlled by the speed setting unit 70. The drive unit 316 is, for example, a stepping motor. The speed setting unit 70 sets the speed of change of the relative position of the antenna 211 with respect to the wireless tag 90, i.e., the linear movement speed, to an appropriate speed by setting the rotational speed of the stepping motor, which is the drive unit 316.

[0027] (Another example of the relative position change section configuration) Next, with reference to Figure 3, another example of the relative position change unit 30 configuration will be described. Figure 3 is a diagram showing another example of the relative position change unit 30 of the wireless tag communication device 10.

[0028] In the example configuration of the relative position changing unit 30 shown in Figure 3, the antenna 20 has two antennas 221 and 222. The antennas 221 and 222 are installed under the table 81 on which the item 80 to which the wireless tag 90 is attached is placed.

[0029] The relative position changing unit 30 has a moving mechanism 320 for moving the antennas 221 and 222. The moving mechanism 320 is a rotation mechanism that rotates the antennas 221 and 222 around a rotation center axis 324. The moving mechanism 320 has a stage 321, a holding part 322, and a drive unit 323. The stage 321 holds the antennas 221 and 222. The holding part 322 rotatably holds the stage 321. The drive unit 323 rotates the holding part 322 around the rotation center axis 324. Therefore, by rotating the holding part 322 that holds the stage 321 with the drive unit 323, the antennas 221 and 222 held on the stage 321 are rotated around the rotation center axis 324.

[0030] The drive unit 323 is controlled by the speed setting unit 70. The drive unit 323 is, for example, a stepping motor. The speed setting unit 70 sets the rotational speed of the stepping motor, which is the drive unit 323, to an appropriate speed, thereby setting the rate of change in the relative position of the antennas 221 and 222 with respect to the wireless tag 90, i.e., the rotational speed.

[0031] (Another example of the relative position change section configuration) Next, with reference to Figure 4, another example of the relative position change unit 30 configuration will be described. Figure 4 is a diagram showing yet another example of the relative position change unit 30 of the wireless tag communication device 10.

[0032] In the example configuration of the relative position changing unit 30 shown in Figure 4, the antenna 20 has multiple antennas, for example, seven antennas 231 to 237. Antennas 231 to 237 are installed under the table 81 on which the item 80 to which the wireless tag 90 is attached is placed. The number of antennas 231 to 237 is not limited to this, and any number is acceptable, but a larger number is preferable.

[0033] The relative position changing unit 30 has a switching unit 330 that switches between antennas 231 to 237. For example, the switching unit 330 switches the transmission and reception functions of antennas 231 to 237 on and off. In other words, the switching unit 330 can transmit and receive radio waves using any of the antennas 231 to 237.

[0034] The switching unit 330 is controlled by the speed setting unit 70. For example, the speed setting unit 70 controls the switching unit 330 to transmit and receive radio waves using one of the antennas 231 to 237 at a time, and to switch the antennas performing the radio wave transmission and reception as time progresses. For example, the speed setting unit 70 controls the switching unit 330 to switch the antennas performing the radio wave transmission and reception along the order of antennas 231 to 237. By setting the time interval for switching the antennas performing the radio wave transmission and reception, the speed setting unit 70 sets the rate of change of the relative position of antennas 231 to 237 with respect to the wireless tag 90, i.e., the switching speed, to an appropriate speed.

[0035] (Hardware configuration) The reading unit 40, inference unit 50, terminal 60, and speed setting unit 70 of the wireless tag communication device 10 are composed of, for example, a computer. The computer includes, for example, a personal computer, a server computer, a tablet, etc.

[0036] In one example, the reading unit 40, the inference unit 50, the terminal 60, and the speed setting unit 70 are all comprised of a single computer. The reading unit 40, the inference unit 50, the terminal 60, and the speed setting unit 70 may each be comprised of a single computer. For example, the terminal 60 may be comprised of a single computer and communicate wirelessly with the other computers comprising the reading unit 40, the inference unit 50, and the speed setting unit 70.

[0037] The following describes an example of the hardware configuration of the computer 100, which comprises the reading unit 40, the inference unit 50, the terminal 60, and the speed setting unit 70, with reference to Figure 5. Figure 5 is a block diagram showing an example of the hardware configuration of the computer 100, which comprises the reading unit 40, the inference unit 50, the terminal 60, and the speed setting unit 70.

[0038] The computer 100 includes a control device 120, an input device 140, and an output device 150.

[0039] The control device 120 controls the entire computer 100. The control device 120 includes a processor 121, a ROM (Read Only Memory) 122, a RAM (Random Access Memory) 123, and an auxiliary storage device 124.

[0040] The processor 121, ROM 122, RAM 123, auxiliary storage device 124, input device 140, and output device 150 are electrically connected to each other via the bus 130, enabling them to send and receive data.

[0041] The processor 121 is composed of a general-purpose hardware processor, such as a CPU (Central Processing Unit) and a GPU (Graphical Processing Unit). The processor 121 executes various functions of the computer 100 by running programs loaded into the RAM 123.

[0042] ROM122 is a non-volatile memory that constitutes part of the main memory. ROM122 non-temporarily stores the startup program necessary for starting up the computer 100. The processor 121 starts up the computer 100 by loading the startup program from ROM122 into RAM123 and executing it. ROM122 is, for example, composed of EPROM (Erasable Programmable Read Only Memory) and can store various startup settings in addition to the startup program.

[0043] RAM123 is a volatile memory that constitutes part of the main memory. RAM123 temporarily stores the programs necessary for processing by the processor 121 and the data necessary for executing those programs. In other words, RAM123 functions as a workspace for the processor 121.

[0044] The auxiliary storage device 124 consists of non-volatile memory such as an HDD (Hard Disk Drive) or SSD (Solid State Drive). The auxiliary storage device 124 can non-temporarily store various programs executed by the processor 121 and the data necessary for the execution of those programs. The processor 121 executes various functions of the computer 100 by loading the programs in the auxiliary storage device 124 into the RAM 123 and executing them.

[0045] The input device 140 is a device for the user to input information or instructions, and accepts the input of information or instructions. The input device 140 includes a keyboard, a pointing device, etc. The pointing device includes a mouse, a trackpad, a touchscreen, etc. The input device 140 also includes sensors. The sensors include a position sensor, a camera, etc. For example, the position sensor includes a home position sensor that detects when the antennas 211, 221, and 222 are in their initial position (home position) when the relative position change unit 30 has the configuration example shown in Figures 2 and 3.

[0046] The output device 150 is a device that outputs information in order to provide information to the user. The output device 150 is, for example, a display device that displays characters, images, etc. on a screen. For example, the output device 150 is a liquid crystal display, an organic EL display, a plasma display, etc. The output device 150 is also, for example, an audio output device and includes a speaker that outputs sound. The output device 150 is also, for example, a light-emitting device that communicates abnormalities by light and includes various light-emitting elements such as LEDs.

[0047] The input device 140 and the output device 150 may be composed of an input / output device having both functions. Such an input / output device may be composed of, for example, a touch panel display.

[0048] Furthermore, the input device 140 may also include devices that take in information or data from external sources. For example, the input device 140 may include wired or wireless interfaces and receiving devices.

[0049] Furthermore, the output device 150 may also include devices that output information or data to the outside. For example, the output device 150 may include wired or wireless interfaces or transmitting devices.

[0050] Furthermore, the input device 140 may also include a device that reads data from a computer-readable recording medium 160 on which data such as programs is stored non-temporarily. For example, the recording medium 160 includes disks such as flexible disks, optical disks (CD-ROM, CD-R, DVD-ROM, DVD-R, etc.), magneto-optical disks (MO, etc.), and semiconductor memory. The input device 140 includes drives and readers for these.

[0051] The program stored in the auxiliary storage device 124 is provided to the computer 100, for example, via the recording medium 160. Alternatively, the program may be stored on a server on a network and provided to the computer 100 by downloading it.

[0052] For example, when the computer 100 starts up, the processor 121 executes the startup program in the ROM 122 to start the operating system (OS). Under the control of the OS, the processor 121 monitors instruction inputs and the connection of external devices. Also, under the control of the OS, the processor 121 sets up a program area and a data area in the RAM 123.

[0053] In response to a program startup instruction input, the processor 121 reads the program from the auxiliary storage device 124 into the program area of ​​the RAM 123, and also reads the data necessary for the execution of the program from the auxiliary storage device 124 into the data area of ​​the RAM 123. The processor 121 performs calculations on the data in the data area according to the program and writes the calculation results to the data area.

[0054] Through this operation, the processor 121, RAM 123, and auxiliary storage device 124 work together to perform at least some of the functions of the control device 120. In addition, the control device 120, input device 140, and output device 150 work together to perform at least some of the functions of the computer 100.

[0055] The program stored non-temporarily in the auxiliary storage device 124 includes a program that causes the processor 121 to execute at least a portion of the functions of the control device 120. In other words, the processor 121 executes at least a portion of the functions of the control device 120 by executing this program.

[0056] For example, a program stored non-temporarily in the auxiliary storage device 124 includes a wireless tag communication program that causes the computer 100 to execute at least some of the functions of the reading unit 40, inference unit 50, terminal 60, and speed setting unit 70 of the wireless tag communication device 10. By the processor 121 executing the wireless tag communication program, the control device 120, in cooperation with the input device 140 and the output device 150, executes at least some of the functions of the reading unit 40, inference unit 50, terminal 60, and speed setting unit 70 of the wireless tag communication device 10.

[0057] (Example of operation of a wireless tag communication device) Next, an example of the operation of the wireless tag communication device 10 will be described with reference to Figure 6. Figure 6 is a flowchart showing an example of the operation of the wireless tag communication device 10. The flowchart shown in Figure 6 is initiated, for example, by inputting an operation start instruction to the terminal 60.

[0058] In ACT11, prior to the reading unit 40 reading the wireless tag 90, the speed setting unit 70 performs a speed setting process. The speed setting unit 70 controls the relative position change unit 30 to set the rate at which the relative position of the antenna 20 with respect to the wireless tag 90 changes. The method for setting the rate of change of relative position will be described later. The relative position change unit 30 changes the relative position of the antenna 20 with respect to the wireless tag 90 at the rate set by the speed setting unit 70.

[0059] In ACT12, the reading unit 40 performs a reading process. The reading unit 40 reads tag data from the wireless tag 90 while the relative position of the antenna 20 with respect to the wireless tag 90 is changed by the relative position change unit 30. As a result, the reading unit 40 reads the tag data of the wireless tag 90 at multiple relative positions of the antenna 20 with respect to the wireless tag 90. The reading unit 40 transmits the read tag data of the wireless tag 90 to the inference unit 50.

[0060] In ACT13, the inference unit 50 performs inference processing. The inference unit 50 infers the placement area of ​​each wireless tag 90 from the tag data of the wireless tag 90 read by the reading unit 40. For example, the inference unit 50 infers whether each wireless tag 90 is inside or outside the placement area. The inference method will be described later. The inference unit 50 transmits the inference result to the terminal 60.

[0061] In ACT14, terminal 60 performs terminal processing. For example, terminal 60 reads and displays the product code and other information from the tag data of the wireless tag 90 that the inference unit 50 has inferred to be within the placement area. For example, if terminal 60 is a cash register terminal, it reads price data and other information in addition to the product code to perform accounting processing. Also, if terminal 60 is a terminal for picking operations, it performs processing such as matching with the delivery schedule list and the shipping schedule list.

[0062] (Example of speed setting process operation) Next, an example of the operation of the speed setting process by the speed setting unit 70 will be described with reference to Figures 7 and 8. This example shows how to present a user interface (UI) screen to the user and set the relative position change rate in response to operations on the UI screen. Figure 7 is a flowchart of this example of the speed setting process. Figure 8 is a diagram showing an example of the UI screen displayed during the speed setting process.

[0063] In ACT21, the speed setting unit 70 instructs the terminal 60 to display a UI screen for speed setting.

[0064] Terminal 60 displays a UI screen for speed settings in ACT22, and waits for user input on the UI screen in ACT23.

[0065] Figure 8 shows an example of the UI screen displayed on terminal 60. For example, the UI screen shown in Figure 8 displays icons A, B, and C for three speed options. The user can select the speed corresponding to icon A, B, or C by clicking on any of the icons. For example, if the speeds corresponding to icons A, B, and C are Va, Vb, and Vc respectively, then Va > Vb > Vc.

[0066] The UI screen shown in Figure 8 is merely an example, and the number of icons is not limited to three; it could be two, four or more, or any number of icons.

[0067] Terminal 60 continues to wait for an operation while no operation is performed on the UI screen (while "No" is displayed in ACT23).

[0068] When an operation is performed on the UI screen (if the answer is Yes in ACT23), terminal 60 sends the result of the operation on the UI screen to speed setting unit 70 in ACT24.

[0069] In ACT25, the speed setting unit 70 sets the setting speed of the relative position change unit 30 to a speed corresponding to the operation result on the UI screen. That is, the speed setting unit 70 controls the relative position change unit 30 so that the relative position of the antenna 20 with respect to the wireless tag 90 changes at a speed corresponding to the operation result on the UI screen.

[0070] In this example, the speed at which the relative position of the antenna 20 relative to the wireless tag 90 changes due to the relative position changing unit 30 is selected by the user. Preferably, the user selects a high speed when the number of wireless tags 90 is small and a low speed when the number of wireless tags 90 is large. Also, in picking operations where the number of wireless tags 90 gradually increases, the user selects a high speed at the beginning of the operation and gradually switches to a low speed as the operation progresses.

[0071] (Another example of speed setting process operation) Next, with reference to Figure 9, another example of the speed setting process by the speed setting unit 70 will be described. This example shows how to set the relative position change rate according to the number of wireless tags 90 read. Figure 9 is a flowchart showing this example of the speed setting process.

[0072] In ACT31, the speed setting unit 70 reads a change speed table that shows the relationship between the number of wireless tags 90 read and the change speed. For example, the change speed table records multiple ranges of the number of wireless tags 90 read and the speed for each range. In the change speed table, the speed for ranges with a small number of wireless tags 90 reads is high, and the speed for ranges with a large number of wireless tags 90 reads is low.

[0073] In ACT32, the reading unit 40 transmits radio waves via the antenna 20 and receives radio waves transmitted from the wireless tag 90 in response to the transmitted radio waves. The reading unit 40 transmits the reception result to the speed setting unit 70.

[0074] In ACT33, the speed setting unit 70 counts the number of wireless tags 90 read from the reception results.

[0075] Next, in ACT34, the speed setting unit 70 sets the set speed of the relative position change unit 30 to a speed corresponding to the number of wireless tags 90 read. Specifically, the speed setting unit 70 refers to the change speed table, identifies a range that includes the number of wireless tags 90 read, and sets the speed for that range to the set speed of the relative position change unit 30.

[0076] In this example, the speed setting unit 70 sets the rate at which the relative position of the antenna 20 relative to the wireless tags 90 changes, according to the number of wireless tags 90 read, by the relative position change unit 30. The speed setting unit 70 also sets the rate at which the relative position of the antenna 20 changes to an appropriate high speed when the number of wireless tags 90 is small, and to an appropriate low speed when the number of wireless tags 90 is large. For example, when the number of wireless tags read is a second number, which is greater than a first number, the speed setting unit 70 sets the rate at which the relative position of the antenna 20 changes to a second rate, which is slower than the first rate at which the number of wireless tags read is a first number. Furthermore, during picking operations, each time a wireless tag 90 is read, the speed setting unit 70 sets the rate at which the relative position of the antenna 20 changes to an appropriate speed. For example, the speed setting unit 70 sets the rate at which the change is made this time to a rate that is slower than the rate at which the change was made the previous time.

[0077] (Another example of speed setting process operation) Next, with reference to Figures 10 and 11, another example of the speed setting process by the speed setting unit 70 will be described. This example shows how to set the relative position change rate during each reading at the end of each picking operation. It also shows how the number of readings in the picking operation is set in advance. Figure 10 is a flowchart of this example of the speed setting process. Figure 11 is a schematic diagram showing an example of a picking operation.

[0078] In ACT41, the speed setting unit 70 determines whether the number of reads has been set. If the number of reads has not been set (if No in ACT41), the process proceeds to the read count setting process in ACT42. If the number of reads has been set (if Yes in ACT41), the process of setting the read count in ACT42 is skipped, and the process proceeds to the read count check process in ACT43.

[0079] If the number of reads has not been set (if it is No in ACT41), ACT42 performs the process of setting the number of reads. The process of setting the number of reads is performed, for example, by displaying a UI screen for setting the number of reads on terminal 60 and having the user input the number of reads on the UI screen.

[0080] In the example picking operation shown in Figure 11, an item is taken from shelf 1, placed on the wireless tag communication device 10 for reading, then moved to shelf 2. Subsequently, an item is taken from shelf 2, placed on the wireless tag communication device 10 for reading, then moved to shelf 3. Subsequently, an item is taken from shelf 3, placed on the wireless tag communication device 10 for reading. In this case, the number of readings is 3.

[0081] When terminal 60 receives input from the user regarding the number of reads on the UI screen, it transmits the read count information to speed setting unit 70. Upon receiving the read count information, speed setting unit 70 checks the read count in ACT43 and sets the rate of change of the relative position of antenna 20 with respect to wireless tag 90 to a speed corresponding to the read count in ACT44.

[0082] For example, if the rate of change during the first reading is V1, the rate of change during the second reading is V2, and the rate of change during the third reading is V3, the speed setting unit 70 sets the rate of change to V1 > V2 > V3.

[0083] (Example of reading process operation) Next, an example of the operation of the reading process by the reading unit 40 will be described with reference to Figure 12. Figure 12 is a flowchart showing an example of the operation of the reading process by the reading unit 40.

[0084] First, the reading unit 40 performs initial setup processing in ACT 51 if necessary. For example, the initial setup processing includes setting antennas 211, 221, and 222 to their initial positions when the relative position change unit 30 has a configuration example that includes, for example, a moving mechanism 310 for moving antenna 211 as shown in Figure 2, and a moving mechanism 320 for moving antennas 221 and 222 as shown in Figure 3.

[0085] Next, in ACT52, the reading unit 40 starts transmitting radio waves via the antenna 20, and in ACT53, the relative position changing unit 30 changes the relative position of the antenna 20 with respect to the wireless tag 90 at the change speed set by the speed setting unit 70.

[0086] If the reading unit 40 is able to read the tag data of the wireless tag 90 in ACT 54 (if the answer is Yes in ACT 54), then in ACT 55, it stores the tag data of the wireless tag 90 that it has read.

[0087] If the reading unit 40 can read the tag data of the wireless tag 90 (if the result is Yes in ACT54), it stores the tag data. Alternatively, if the reading unit 40 cannot read the tag data of the wireless tag 90 (if the result is No in ACT54), in ACT56, the relative position change unit 30 determines whether the change in the relative position of the antenna 20 with respect to the wireless tag 90 is complete. Until the change in the relative position of the antenna 20 with respect to the wireless tag 90 is complete (if the result is No in ACT56), the reading unit 40 repeatedly performs the processes of ACT54 and ACT55.

[0088] Once the relative position of the antenna 20 with respect to the wireless tag 90 has finished changing (if Yes in ACT56), the reading unit 40 terminates the transmission of radio waves in ACT57 and transmits the read tag data to the inference unit 50 in ACT58.

[0089] (Example of inference process operation) Next, with reference to Figure 13, an example of the operation of the inference processing by the inference unit 50 will be described. Figure 13 is a flowchart showing an example of the operation of the inference processing by the inference unit 50. This example uses a pre-trained model obtained by machine learning to infer whether the wireless tag 90 is inside or outside the deployment area.

[0090] In ACT61, the inference unit 50 receives tag data from the wireless tag 90 from the reading unit 40.

[0091] In ACT62, the inference unit 50 uses a machine learning-trained model to infer whether each wireless tag 90 is inside or outside the deployment area from the tag data at multiple relative positions of each received wireless tag 90.

[0092] The inference unit 50 repeatedly performs the inference in ACT62 until the inference is completed for all wireless tags 90 (while the result in ACT63 is "No").

[0093] Once inference is complete for all wireless tags 90 (if Yes in ACT63), the inference unit 50 transmits the inference results to the terminal 60 in ACT64.

[0094] (Another example of inference processing behavior) Next, with reference to Figure 14, another example of the inference processing by the inference unit 50 will be described. Figure 14 is a flowchart showing another example of the inference processing by the inference unit 50. This example infers whether the wireless tag 90 is inside or outside the deployment area based on the phase difference of the radio waves received from the wireless tag 90.

[0095] In ACT71, the inference unit 50 receives tag data from the wireless tag 90 from the reading unit 40.

[0096] In ACT72, the inference unit 50 calculates the phase difference, which is the change in the phase of the tag data in response to the change in relative position at multiple relative positions of each received wireless tag 90, and determines whether the phase difference is greater than or equal to a threshold.

[0097] If the phase difference is greater than or equal to a threshold (Yes in ACT72), then in ACT73, the inference unit 50 infers that the wireless tag 90 is within the placement area.

[0098] Conversely, if the phase difference is less than the threshold (No in ACT72), then in ACT74, the inference unit 50 infers that the wireless tag 90 is outside the deployment area.

[0099] The inference unit 50 repeatedly performs the inferences in ACT72 to ACT74 until the inference is completed for all wireless tags 90 (while the result is "No" in ACT75).

[0100] Once inference is complete for all wireless tags 90 (if Yes in ACT75), the inference unit 50 transmits the inference results to the terminal 60 in ACT76.

[0101] (Example of terminal processing operation) As mentioned above, for example, terminal 60 reads and displays the product code and other information from the tag data of the wireless tag 90 that the inference unit 50 has inferred to be within the placement area. For example, if terminal 60 is a cash register terminal, it reads price data and other information in addition to the product code to perform accounting processing. Also, if terminal 60 is a terminal for picking operations, it performs processing such as matching with the delivery schedule list and the shipping schedule list.

[0102] (effect) In the embodiment of the wireless tag communication device 10, prior to the reading unit 40 reading the wireless tag 90, the speed setting unit 70 sets the rate of change of the relative position of the antenna 20 with respect to the wireless tag 90 to an appropriate speed, that is, a speed at which a sufficient amount of data can be acquired even if the number of responses from the wireless tag 90 decreases due to anti-collision. This prevents a decrease in the accuracy of inferring the placement area of ​​the wireless tag due to anti-collision.

[0103] The program according to this embodiment may be transferred while stored on an electronic device, or it may be transferred while not stored on an electronic device. In the latter case, the program may be transferred via a network, or it may be transferred while stored on a storage medium. The storage medium is a non-temporary tangible medium. The storage medium is a computer-readable medium. The storage medium can be any medium that is capable of storing a program and is readable by a computer, such as a CD-ROM or memory card, and its form is not limited.

[0104] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of Symbols]

[0105] 10...Wireless tag communication device, 20...Antenna, 30...Relative position change unit, 40...Reading unit, 50...Inference unit, 60...Terminal, 70...Speed ​​setting unit, 80...Item, 81...Table, 90...Wireless tag, 100...Computer, 120...Control device, 121...Processor, 122...ROM, 123...RAM, 124...Auxiliary storage device, 130...Bus, 140...Input device, 150...Output device, 160...Recording medium, 211...Antenna, 310...Moving mechanism, 311...Stage, 312...Guide rail, 313...Ball screw, 314...Screw shaft, 315...Nut, 316...Drive unit, 221, 222...Antenna, 320...Moving mechanism, 321...Stage, 322...Holding unit, 323...Drive unit, 324...Rotation center axis, 231~237...Antenna, 330...Switching unit.

Claims

1. An antenna that receives radio waves transmitted from a wireless tag, A relative position changing unit that changes the relative position of the antenna with respect to the wireless tag, A reading unit reads the tag data of the wireless tag at multiple relative positions of the antenna to the wireless tag based on the radio waves received by the antenna. An inference unit that infers the placement area of ​​the wireless tag from the tag data, A speed setting unit that sets the rate of change of the relative position of the antenna with respect to the wireless tag, A wireless tag communication device having the following features.

2. When the number of wireless tags read by the reading unit is a second number greater than the first number, the speed setting unit sets the speed to a second rate of change that is slower than the first rate of change when the number of wireless tags is the first number. The wireless tag communication device according to claim 1.

3. The speed setting unit sets the current rate of change to a lower rate of change than the previous rate of change. The wireless tag communication device according to claim 1.

4. The aforementioned relative position changing unit is The antenna has a moving mechanism for moving the aforementioned antenna, The speed setting unit controls the drive unit of the moving mechanism. The wireless tag communication device according to claim 1.

5. The aforementioned relative position changing unit is Multiple antennas, It has a switching unit that switches the receiving function of the multiple antennas on and off, The speed setting unit controls the switching unit. The wireless tag communication device according to claim 1.

6. On the computer, A function to read the tag data of the wireless tag at multiple relative positions of the antenna to the wireless tag, based on radio waves transmitted from the wireless tag and received by the antenna, A function to infer the placement area of ​​the wireless tag using the aforementioned tag data, A function to set the rate of change of the relative position of the antenna with respect to the wireless tag, A wireless tag communication program that enables this operation.

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