Communication device and control program for the communication device

Abstract

This invention provides a communication device and a control program for the communication device that improve the accuracy of determining the location of wireless tags. [Solution] The communication device according to the embodiment comprises an antenna, a determination unit, and a processing unit. The antenna receives radio waves from a wireless tag. The determination unit determines, based on information from multiple radio waves received by the antenna, whether the wireless tag is in a first state where it is in a first region, or a second state where it is in a second region that does not include the first region, under multiple conditions where the relative positions of the wireless tag and the antenna are different. The processing unit outputs a processing result indicating whether the wireless tag is in the first state or the second state, based on multiple determination results from the determination unit regarding the wireless tag.

Description

【Technical Field】 【0001】 Embodiments of the present invention relate to a communication device and a control program for the communication device. 【Background Art】 【0002】 There is known a communication device that determines whether a wireless tag is within a predetermined range or outside the predetermined range by receiving radio waves transmitted from the wireless tag attached to an article with an antenna. 【Prior Art Documents】 【Patent Documents】 【0003】 【Patent Document 1】 Japanese Patent Application Laid-Open No. 2023-35625 【Summary of the Invention】 【Problems to be Solved by the Invention】 【0004】 ​​​​​​​​​​​​​​​[Figure 1] A block diagram showing an example configuration of a communication system according to the embodiment. [Figure 2] A block diagram showing an example configuration of a reading device according to the embodiment. [Figure 3] A block diagram showing an example configuration of a drive device according to an embodiment. [Figure 4] A schematic diagram showing an overview of the communication system according to the embodiment. [Figure 5] A plan view showing the first and second regions in the communication system according to the embodiment. [Figure 6] A flowchart illustrating the reading process of the communication device according to the embodiment. [Figure 7] A flowchart illustrating the tag data acquisition process of a communication device according to an embodiment. [Figure 8] A flowchart illustrating the determination process by the inference machine of the communication device according to the embodiment. [Figure 9] A flowchart illustrating the determination result evaluation process of a communication device according to an embodiment. [Figure 10] A flowchart illustrating the operation of the inference machine included in the communication device according to the embodiment. [Figure 11] A flowchart illustrating the phase difference determination process of a communication device related to a modified example. [Modes for carrying out the invention] 【0007】 The embodiments will be described below with reference to the drawings. In the description, components having substantially the same function and configuration will be denoted by the same reference numerals. Furthermore, the embodiments shown below are illustrative of the technical concept. The embodiments do not specify the material, shape, structure, arrangement, etc., of the components. Various modifications can be made to the embodiments. 【0008】 <Structure> Figure 1 is a block diagram showing an example configuration of a communication system according to an embodiment. The communication system 1 includes a communication device 10 and a plurality of articles 600, each with a wireless tag 700 attached. The communication system 1 is a system in which the communication device 10 and the wireless tag 700 communicate and determine whether the wireless tag 700 is within a predetermined area. In Figure 1, one article 600 with a wireless tag 700 attached is shown, but the communication system 1 includes a plurality of articles 600 with wireless tags 700 attached. 【0009】 The communication device 10 is a device that reads information from the wireless tag 700 and processes the read information. The communication device 10 can be used for picking up inventory in a warehouse, but the applications of the communication device 10 are not limited to this. The communication device 10 includes a reader 100, a drive unit 200, an antenna 300, a terminal 400, and an inference unit 500. 【0010】 The reader 100 controls the drive unit 200 and the antenna 300 to read information from the wireless tag 700. The reader 100 also inputs the information read from the wireless tag 700 to the inference unit 500 to obtain an inference result. The reader 100 then makes a judgment based on the inference result and outputs the judgment result to the terminal 400. Details of the reader 100 will be described later. 【0011】 The drive unit 200 is a device for moving the antenna 300. Details of the drive unit 200 will be described later. 【0012】 Antenna 300 transmits and receives radio waves to and from wireless tag 700. Antenna 300 converts the radio waves received from wireless tag 700 into a high-frequency signal and outputs the high-frequency signal to reader device 100. 【0013】 Terminal 400 is a terminal that transmits and receives information with the reader 100 and displays the judgment result to the user. Terminal 400 also receives input from the user and transmits the user's input to the reader 100. Terminal 400 is, for example, an information processing terminal such as a PC (Personal Computer), smartphone, or tablet. 【0014】 The inference machine 500 is a device that outputs an inference result based on the input information. The inference machine 500 includes, for example, an arithmetic circuit that performs inference by utilizing machine learning. The inference machine 500 estimates whether the wireless tag 700 is within a predetermined area based on the information input from the reading device 100. 【0015】 The article 600 is a commodity or the like. 【0016】 The wireless tag 700 is typically an RFID (Radio Frequency Identification) tag. The wireless tag 700 may be other wireless tags. The wireless tag 700 is a passive wireless tag that operates using a predetermined radio wave transmitted from the antenna 300 as an energy source. The wireless tag 700 transmits a signal including the information stored in the wireless tag 700 by performing backscatter modulation on an unmodulated signal. The information stored in the wireless tag 700 may include uniquely identifiable identification information. The information stored in the wireless tag 700 may include information regarding the article 600 to which the wireless tag 700 is attached. 【0017】 FIG. 2 is a block diagram showing a configuration example of a reading device according to an embodiment. The reading device 100 includes a processor 101, a ROM (Read Only Memory) 102, a RAM (Random Access Memory) 103, a storage 104, a first connection interface 105, a second connection interface 106, a third connection interface 107, a high-frequency front end 108, a digital amplitude modulation unit 109, a DA (Digital to Analog) conversion unit 110, an AD (Analog to Digital) conversion unit 111, a demodulation unit 112, and a bus 113. The bus 113 includes an address bus, a data bus, control signal lines, and the like. The bus 113 connects the processor 101, the ROM 102, the RAM 103, the storage 104, the first connection interface 105, the second connection interface 106, the third connection interface 107, the high-frequency front end 108, the digital amplitude modulation unit 109, the DA conversion unit 110, the AD conversion unit 111, and the demodulation unit 112 to each other. The connection of the processor 101, the ROM 102, the RAM 103, and the storage 104 by the bus 113 forms a computer of the reading device 100. 【0018】 The processor 101 corresponds to the central part of the above computer. The processor 101 controls each part to realize various functions as the reading device 100 according to an operating system or an application program. The processor 101 is a CPU (Central Processing Unit), an MPU (Micro Processing Unit), a SoC (System on a Chip), a DSP (Digital Signal Processor), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), or an FPGA (Field Programmable Gate Array), etc. The processor 101 may be a combination of a plurality of these. 【0019】 ROM102 is a non-volatile memory device. ROM102 stores pre-configured operating systems or application programs, control data, and the like. 【0020】 RAM103 is a volatile memory device. RAM103 is used as a work area where data is rewritten as needed by the processor 101. RAM103 is also used as a buffer memory for temporarily storing data. 【0021】 Storage 104 corresponds to the auxiliary storage portion of the computer described above. Storage 104 stores data used by the processor 101 in performing various processes, data created by the processing performed by the processor 101, etc. Storage 104 may also store the application programs described above. Storage 104 is, for example, EEPROM (registered trademark) (Electric Erasable Programmable Read Only Memory), HDD (Hard Disk Drive), SSD (Solid State Drive), etc. 【0022】 The first connection interface 105 is an interface for the reader 100 to communicate with the drive unit 200. 【0023】 The second connection interface 106 is an interface for the reader 100 to communicate with the terminal 400. 【0024】 The third connection interface 107 is an interface for the reader 100 to communicate with the inference machine 500. 【0025】 The high-frequency front-end 108 outputs a high-frequency signal to the antenna 300. The high-frequency front-end 108 receives a high-frequency signal from the antenna 300. 【0026】 The digital amplitude modulation unit 109 is a circuit that adds information to be transmitted to the wireless tag 700 to the carrier wave transmitted to the wireless tag 700. 【0027】 The DA conversion unit 110 is a circuit that converts a digital signal to an analog signal. The DA conversion unit 110 converts the digital signal modulated by the digital amplitude modulation unit 109 into an analog signal. The DA conversion unit 110 outputs a high-frequency signal to the antenna 300 via the high-frequency front end 108. 【0028】 The AD conversion unit 111 is a circuit that converts an analog signal into a digital signal. The AD conversion unit 111 converts the high-frequency signal input from the antenna 300 into a digital signal via the high-frequency front end 108. 【0029】 The demodulation unit 112 is a circuit that extracts various information from radio waves received from the wireless tag 700. For example, the demodulation unit 112 extracts a unique identification code stored in the wireless tag 700 from the digital signal converted by the AD conversion unit 111. Also, using known technology, when the antenna 300 receives radio waves from the wireless tag 700, the demodulation unit 112 outputs tag data of the wireless tag 700 in a time series from the digital signal converted by the AD conversion unit 111. The tag data is time series data based on the radio waves from the wireless tag 700 received by the antenna 300. The tag data includes phase data. Phase data is data indicating the phase of the radio waves from the wireless tag 700. The tag data includes radio wave reception strength (RSSI (Received Signal Strength Indicator)) data. Radio wave reception strength data is data indicating the reception strength of the radio waves from the wireless tag 700. The tag data may include both phase data and radio wave reception strength data. Furthermore, each wireless tag 700 may store radio wave reception strength data in its own memory when it receives radio waves transmitted from the antenna 300. In this example, the demodulation unit 112 may extract the radio wave reception strength data stored in the wireless tag 700 in chronological order from the digital signal converted by the AD conversion unit 111. 【0030】 The various parts implemented by the processor 101 will now be described. The processor 101 implements the determination unit 1011 and the processing unit 1012. The various parts implemented by the processor 101 can also be called various functions. The various parts implemented by the processor 101 can also be said to be implemented by a control unit including the processor 101, ROM 102, and RAM 103. 【0031】 The determination unit 1011 determines from multiple tag data whether the wireless tag 700 is within a predetermined area. 【0032】 The processing unit 1012 outputs a processing result indicating whether the wireless tag 700 is in the first state or the second state, based on the multiple determination results from the determination unit 1011. 【0033】 The information stored in storage 104 is described below. Storage 104 stores, for at least one of the multiple wireless tags 700, multiple tag data compiled for each measurement count, a judgment result associated with the judgment count, various flags, and processing results. The measurement count is a value indicating which measurement it is, when a series of operations to acquire tag data is considered one measurement, and will be described later. The judgment count is a value indicating which judgment it is, when one judgment is made based on the tag data obtained from one measurement to determine whether the tag is inside or outside the area, as described later. The judgment result is information obtained as a result of making the determination whether the tag is inside or outside the area, as described later. Various flags are, for example, the inside-area flag, the outside-area flag, and the outside-area confirmation flag, as described later. The processing result is information obtained based on multiple judgment results, indicating whether the tag is located inside or outside the area, as described later. 【0034】 The drive unit 200 will be described with reference to Figures 3 and 4. Figure 3 is a block diagram showing an example configuration of the drive unit according to the embodiment. The drive unit 200 includes a processor 201, a ROM 202, a RAM 203, a connection interface 204, a drive unit 205, a home position sensor 206, and a bus 207. The bus 207 includes an address bus, a data bus, and control signal lines, etc. The bus 207 connects the processor 201, the ROM 202, the RAM 203, the connection interface 204, the drive unit 205, and the home position sensor 206 to each other. The computer of the drive unit 200 is formed by connecting the processor 201, the ROM 202, and the RAM 203 via the bus 207. 【0035】 The processor 201 corresponds to the central part of the computer described above. The processor 201 controls each part to realize various functions as a drive unit 200 according to the operating system or application program. The processor 201 is a CPU, MPU, SoC, DSP, GPU, ASIC, PLD, or FPGA, etc. The processor 201 may be a combination of several of these. 【0036】 ROM202 is a non-volatile storage device. ROM202 stores pre-configured operating systems or application programs, as well as control data, etc. 【0037】 RAM203 is a volatile memory device. It is used as a work area where data is periodically rewritten by processor 201. RAM203 is also used as a buffer memory for temporarily storing data. 【0038】 The connection interface 204 is an interface for the drive unit 200 to connect with the reader unit 100. 【0039】 The drive unit 205 moves the antenna 300. For example, the drive unit 205 is a stepping motor. 【0040】 The home position sensor 206 is a sensor that detects whether or not the moving stage 213, which will be described later, is in the home position. 【0041】 Figure 4 is a schematic diagram showing an overview of the communication system according to the embodiment. As shown in Figure 4, the drive unit 200 and the antenna 300 are housed inside the case CAS. The case CAS is a rectangular parallelepiped housing, and at least the top surface is transparent to radio waves. In Figure 4, among the elements included in the drive unit 200, the drive unit 205, the rotating shaft 211, the rail 212, and the moving stage 213 are shown. 【0042】 The rotating shaft 211 transmits the driving force of the drive unit 205. Screw grooves are formed on the rotating shaft 211 and the rail 212. The screw grooves on the rotating shaft 211 and the screw grooves on the rail 212 are connected opposite each other. Therefore, when the drive unit 205 is driven to rotate, the rotating shaft 211 rotates, and the rail 212 rotates. A mobile stage 213 on which the antenna 300 is mounted is attached to the rail 212. 【0043】 The moving stage 213 is equipped with a ball screw nut, and moves horizontally when the rail 212 rotates due to the ball screw nut. That is, the moving stage 213 moves in the direction along the X-axis as shown in Figure 4. Also, if the rotation direction of the rail 212 is reversed, the moving stage 213 moves in the opposite direction. In this way, the drive device 200 moves the antenna 300 back and forth along the rail 212 in one direction along the X-axis. 【0044】 The configuration of the communication system 1 will now be described with reference to Figure 4. The communication system 1 is used, for example, mounted on a trolley. The example shown in Figure 4 shows a trolley including a chassis CHA, a handle HDL, and multiple wheels WHE. The chassis CHA is a rectangular, plate-shaped structural member and is the chassis of the trolley. Multiple wheels WHE are provided on the bottom surface of the chassis CHA. The wheels WHE are wheels. A handle HDL is provided at the end of the top surface of the chassis CHA. The handle HDL is a handle used by the user of the trolley to operate the trolley. 【0045】 Case CAS is placed on the loading surface of the trolley, i.e., the top surface of chassis CHA. Container CON is placed on top of case CAS. Container CON is a box for storing item 600. Container CON is made of a material that transmits radio waves. Item 600 with a wireless tag 700 attached is stored inside Container CON. 【0046】 Terminal 400 is installed on top of the Handle HDL. 【0047】 The first and second regions will now be described. Figure 5 is a plan view showing the first and second regions in the communication system according to the embodiment. Figure 5 is a plan view from above of the communication system 1 described with reference to Figure 4. 【0048】 The first region 81 and the second region 82 are regions separated horizontally. The first region 81 is the region set in the central part of the top surface of the case CAS. The first region 81 includes at least the area in which the container CON is placed. The second region 82 is the region set to surround the first region 81. The second region 82 can also be described as the region that is not the first region 81, the region outside the first region 81, etc. 【0049】 <Operation> The communication system 1 according to this embodiment is used, for example, in the pickup of inventory in a warehouse. The user pushes a cart equipped with the communication system 1 around a warehouse where shelves are lined with numerous items 600 with wireless tags 700 attached, and stores the desired items 600 in container CON. The communication system 1 identifies the picked-up items 600 by identifying the wireless tags 700 included in the first area 81. The operation of the communication device 10 of the communication system 1 used in this way will be described in detail with reference to Figures 6 to 10. In the following description, for the sake of simplicity, the processing of one wireless tag 700 will be described, but in actual operation, processing will be performed in parallel for multiple wireless tags 700 that can communicate with the communication device 10. 【0050】 Figure 6 is a flowchart showing the reading process of the communication device according to the embodiment. When a user operates the terminal 400 to start the reading process (start), the communication device 10 executes the tag data acquisition process (ACT10). In detail, the processor 101 of the reading device 100 executes the tag data acquisition process. Details of the tag data acquisition process will be explained with reference to Figure 7. 【0051】 Figure 7 is a flowchart illustrating the tag data acquisition process of the communication device according to the embodiment. When the tag data acquisition process is started (start), the communication device 10 acquires the antenna position (ACT 11). Specifically, the processor 101 of the reader device 100 controls the first connection interface 105 to query the drive device 200 for the position of the antenna 300. The processor 201 of the drive device 200 receives the query for the position of the antenna 300 via the connection interface 204. The processor 201 controls the home position sensor 206 to acquire the position of the antenna 300. The processor 201 controls the connection interface 204 to transmit the position of the antenna 300 to the reader device 100. The processor 101 of the reader device 100 acquires the position of the antenna 300 via the first connection interface 105. 【0052】 The communication device 10 determines whether the antenna position is the starting point (ACT12). Specifically, the processor 101 of the reading device 100 determines whether the position of the antenna 300 obtained in the ACT11 process is the starting point. If the position of the antenna 300 is the starting point (ACT12, Yes), the communication device 10 executes the process of ACT14. 【0053】 If the antenna 300 is not at the starting point (ACT12, No), the communication device 10 moves the antenna 300 to the starting point (ACT13). Specifically, the processor 101 of the reader 100 controls the first connection interface 105 to send a command to the drive unit 200 to move the antenna 300 to the starting point. The processor 201 of the drive unit 200 receives the command via the connection interface 204. The processor 201 controls the drive unit 205 to move the antenna 300 to the starting point. 【0054】 The communication device 10 starts transmitting radio waves (ACT 14). Specifically, the processor 101 of the reader 100 controls the high-frequency front end 108 to transmit radio waves from the antenna 300. 【0055】 The communication device 10 starts moving the antenna 300 (ACT 15). Specifically, the processor 101 of the reading device 100 controls the first connection interface 105 and sends a command to the drive device 200 to start moving the antenna 300. The processor 201 of the drive device 200 receives the command via the connection interface 204. The processor 201 controls the drive unit 205 to start moving the antenna 300. 【0056】 The communication device 10 determines whether tag data has been acquired (ACT16). Specifically, the processor 101 of the reader 100 controls the demodulation unit 112 to determine whether tag data has been acquired. If tag data has been acquired (ACT16, Yes), the communication device 10 saves the tag data (ACT17). Specifically, the processor 101 of the reader 100 controls the storage 104 to save the acquired tag data. After the processing of ACT17 is completed, the communication device 10 executes the processing of ACT18. If tag data was not acquired in the processing of ACT16 (ACT16, No), the communication device 10 executes the processing of ACT18. 【0057】 The communication device 10 determines whether the movement of the antenna 300 has finished (ACT 18). Specifically, the processor 101 of the reading device 100 controls the first connection interface 105 to query the drive device 200 whether the movement of the antenna 300 has finished. The processor 201 of the drive device 200 receives the query via the connection interface 204. The processor 201 checks how the drive unit 205 is being controlled and confirms whether the movement of the antenna 300 has finished. The processor 201 sends the query result to the reading device 100 via the connection interface 204. The processor 101 of the reading device 100 determines from the received result whether the movement of the antenna 300 has finished. 【0058】 If the movement of antenna 300 is not yet complete (ACT18, No), the communication device 10 executes the process of ACT16. That is, the communication device 10 repeats the processes of ACT16, ACT17, and ACT18 until the movement of antenna 300 is complete. In this way, the communication device 10 acquires multiple tag data while moving antenna 300. The acquisition of tag data performed from the start of antenna 300's movement until the end of antenna 300's movement corresponds to one measurement. 【0059】 In the processing of ACT18, if the movement of the antenna 300 has been completed (ACT18, Yes), the communication device 10 terminates the transmission of radio waves (ACT19). Specifically, the processor 101 of the reading device 100 controls the high-frequency front end 108 to terminate the transmission of radio waves from the antenna 300. 【0060】 Once the ACT19 process is complete, the tag data acquisition process shown in Figure 7 will also end (end). 【0061】 Returning to the explanation with reference to Figure 6, once the tag data acquisition process, which is the process of ACT10, is completed, the communication device 10 executes a determination process by the inference machine (ACT20). In detail, the processor 101 of the reading device 100 executes the determination process by the inference machine. Details of the determination process by the inference machine will be explained with reference to Figure 8. 【0062】 Figure 8 is a flowchart illustrating the determination process by the inference machine of the communication device according to the embodiment. When the determination process by the inference machine is executed (start), the communication device 10 transmits the tag data to the inference machine (ACT21). Specifically, the processor 101 of the reader device 100 transmits the tag data stored in the storage 104 to the inference machine 500 by controlling the third connection interface 107. In this process, multiple tag data corresponding to a single measurement are transmitted to the inference machine 500. 【0063】 The communication device 10 determines whether it has received a determination result (ACT22). Specifically, the processor 101 of the reading device 100 determines whether it has received a determination result from the inference machine 500 via the third connection interface 107. If it has not received a determination result (ACT22, No), the communication device 10 executes ACT22 again. That is, the processor 101 of the reading device 100 repeats the process of ACT22 until it receives a determination result from the inference machine 500. 【0064】 In the processing of ACT22, if a determination result is received (ACT22, Yes), the communication device 10 saves the determination result (ACT23). Specifically, the processor 101 of the reader device 100 controls the storage 104 to save the determination result. Here, the determination result is either a first state in which the wireless tag 700 is included in the first area 81, or a second state in which the wireless tag 700 is included in the second area 82. Hereafter, the first state in which it is included in the first area 81 will also be referred to as "in the area," and the second state in which it is included in the second area 82 will also be referred to as "out of the area." 【0065】 Once the ACT23 process is complete, the decision-making process by the inference machine shown in Figure 8 is terminated (end). 【0066】 Returning to the explanation with reference to Figure 6, once the inference machine's determination process, which is ACT20, is completed, the communication device 10 executes the determination result evaluation process (ACT30). In detail, the processor 101 of the reading device 100 executes the determination result evaluation process. The determination result evaluation process will be explained with reference to Figure 9. 【0067】 Figure 9 is a flowchart showing the determination result evaluation process of the communication device according to the embodiment. When the determination result evaluation process is executed (start), the communication device 10 determines whether it has performed determination two or more times (ACT31). In detail, the processor 101 of the reader device 100 determines whether the determination process by the inference machine has been performed two or more times for the wireless tag 700 to be evaluated. 【0068】 If the inference machine performs the determination process two or more times (ACT31, Yes), the communication device 10 compares the Nth determination result with the N+1th determination result (ACT32). Here, N is a natural number, and the latest determination result is set to correspond to the N+1th determination. Specifically, the processor 101 of the reading device 100 reads the determination result from the storage 104 and compares the Nth determination result with the N+1th determination result. 【0069】 The communication device 10 determines whether the judgment result is within both areas or outside both areas (ACT33). Specifically, the processor 101 of the reading device 100 determines whether the Nth judgment result and the N+1th judgment result, which were compared in the ACT32 process, are both within or outside both areas. 【0070】 If neither is within the region or neither is outside the region (ACT33, No), the communication device 10 determines whether the Nth result is within the region (ACT34). Specifically, the processor 101 of the reader 100 determines whether the Nth result, compared in the process of ACT32, is within the region. 【0071】 If the Nth attempt is not within the area (ACT34, No), the communication device 10 increments the area flag (ACT35). Specifically, the processor 101 of the reader 100 controls the storage 104 to increment and save the area flag for the wireless tag 700 currently being handled. The area flag is a variable that indicates the possibility that the wireless tag 700 is within the area. The area flag may also be called the first flag. 【0072】 In the processing of ACT34, if the Nth time the data was within the area (ACT34, Yes), the communication device 10 determines whether there was insufficient data on the N+1th time (ACT36). Specifically, the processor 101 of the reading device 100 controls the storage 104 to read the tag data corresponding to the N+1th determination result compared in the processing of ACT32, and determines whether there was insufficient data. 【0073】 If there is no data shortage on the N+1th attempt (ACT36, No), the communication device 10 increments the out-of-bounds flag (ACT37). Specifically, the processor 101 of the reader 100 controls the storage 104 to increment and save the out-of-bounds flag for the wireless tag 700 currently being handled. The out-of-bounds flag is a variable that indicates the possibility that the wireless tag 700 is outside the designated area. The out-of-bounds flag may also be called the second flag. 【0074】 In the processing of ACT36, if there is insufficient data on the N+1th attempt (ACT36, Yes), the communication device 10 clears the in-area flag and the out-of-area flag (ACT38). Specifically, the processor 101 of the reader device 100 controls the storage 104 to clear the in-area flag and the out-of-area flag to "0" for the wireless tag 700 currently being handled, and saves it. 【0075】 The communication device 10 sets an out-of-bounds confirmation flag (ACT39). Specifically, the processor 101 of the reader device 100 controls the storage 104 to enable and save the out-of-bounds confirmation flag for the wireless tag 700 currently being handled. The out-of-bounds confirmation flag is a variable that indicates there is a high probability that the wireless tag 700 is outside the designated area. When the out-of-bounds confirmation flag is enabled, the processing result in the subsequent processing is fixed as out of the designated area. 【0076】 The judgment result evaluation process shown in Figure 9 terminates (terminates) if the process of ACT31 has not been judged more than twice (ACT31, No), if the process of ACT33 is either within or outside both regions (ACT33, Yes), if the process of ACT35 is completed, if the process of ACT37 is completed, or if the process of ACT39 is completed. 【0077】 Returning to the explanation with reference to Figure 6, once the judgment result evaluation process, which is the process of ACT30, is completed, the communication device 10 determines whether there is an out-of-bounds confirmation flag (ACT41). In detail, the processor 101 of the reader device 100 controls the storage 104 to read the out-of-bounds confirmation flag for the wireless tag 700 currently being handled and determines whether the out-of-bounds confirmation flag is enabled. 【0078】 If there is no out-of-bounds confirmation flag (ACT41, No), the communication device 10 determines whether there is an out-of-bounds flag or an in-bounds flag (ACT42). Specifically, the processor 101 of the reader device 100 controls the storage 104 to read out the out-of-bounds flag and in-bounds flag for the wireless tag 700 currently being handled, and determines whether the out-of-bounds flag or the in-bounds flag is counted. 【0079】 If there is no out-of-bounds flag or in-bounds flag (ACT42, No), the communication device 10 determines the processing result as the judgment result (ACT43). Specifically, the processor 101 of the reader 100 controls the storage 104 to set the processing result for the currently handled wireless tag 700 to be equal to the most recent judgment result and saves it. 【0080】 In the processing of ACT42, if there is an out-of-bounds flag or an in-bounds flag (ACT42, Yes), the communication device 10 determines whether the in-bounds flag is greater than the out-of-bounds flag (ACT44). Specifically, the processor 101 of the reader device 100 controls the storage 104 to read the in-bounds flag and out-of-bounds flag for the wireless tag 700 currently being handled, and determines whether the count value of the in-bounds flag is greater than the count value of the out-of-bounds flag. 【0081】 If the in-area flag is greater than the out-of-area flag (ACT44, Yes), the communication device 10 determines the processing result to be within the area (ACT45). Specifically, the processor 101 of the reader device 100 controls the storage 104 to set and save the processing result for the currently handled wireless tag 700 within the area. 【0082】 If the out-of-bounds confirmation flag is present during the processing of ACT41 (ACT41, Yes), and if the in-bounds flag is not greater than the out-of-bounds flag during the processing of ACT44 (ACT44, No), the communication device 10 determines the processing result to be out of bounds (ACT46). Specifically, the processor 101 of the reader device 100 controls the storage 104 to set the processing result for the currently handled wireless tag 700 to out of bounds and save it. 【0083】 When the processing of ACT43 is completed, when the processing of ACT45 is completed, and when the processing of ACT46 is completed, the communication device 10 outputs the processing result to the terminal 400 (ACT47). Specifically, the processor 101 of the reading device 100 controls the storage 104 to read the processing result. Then, the processor 101 controls the second connection interface 106 to output the processing result to the terminal 400. 【0084】 The communication device 10 determines whether the exit button has been pressed (ACT48). Specifically, the processor 101 of the reading device 100 determines whether it has received information from the terminal 400 via the second connection interface 106 indicating that the exit button has been pressed. If the exit button has not been pressed (ACT48, No), the communication device 10 executes the process of ACT10. That is, the communication device 10 repeats the processes from ACT10 to ACT48 until the exit button on the terminal 400 is pressed. 【0085】 In the processing of ACT48, if the exit button is pressed (ACT48, Yes), the communication device 10 outputs an exit screen to the terminal (ACT49). Specifically, the processor 101 of the reading device 100 controls the second connection interface 106 and outputs a command to the terminal 400 to display the exit screen. 【0086】 Once the ACT49 process is complete, the reading process shown in Figure 6 is terminated (end). 【0087】 Figure 10 is a flowchart showing the operation of the inference machine included in the communication device according to the embodiment. When the reader 100 transmits tag data to the inference machine 500 (start), the inference machine 500 receives the tag data (ACT 51). The inference machine 500 determines the region based on the tag data and the learned model (ACT 51). If the tag data is insufficient, the inference machine 500 determines that it is outside the region. The inference machine 500 transmits the determination result (ACT 53). In detail, the inference machine 500 transmits the determination result to the reader 100. When the processing of ACT 53 is completed, the series of processes shown in Figure 10 is completed (end). 【0088】 <Effects> In a system that determines whether a wireless tag is within or outside a designated area, misidentification of the tag's location is possible if the tag is located near the boundary between the inside and outside of the area. If such a system is applied to picking up items in a warehouse, misidentification of the area may occur when reading a wireless tag near the shelves where the inventory is stored. 【0089】 According to the embodiment, the communication device 10 includes an antenna 300 that receives radio waves from the wireless tag 700, a determination unit 1011 that determines whether the wireless tag 700 is in a first state where it is in a first region or a second state where it is in a second region that does not include the first region, based on information from multiple radio waves received by the antenna 300 under multiple conditions where the relative positions of the wireless tag 700 and the antenna 300 are different, and a processing unit 1012 that outputs a processing result indicating whether the wireless tag 700 is in the first or second state based on multiple determination results from the determination unit 1011 regarding the wireless tag 700. For example, if the communication device 10 is used to pick up items in a warehouse, misjudgments may occur near shelves where inventory is stored, but if the measurement is performed again at a location away from the shelves where inventory is stored, it is conceivable that a correct determination result can be obtained. Therefore, the communication device 10 according to the embodiment can suppress the effects of misjudgments and output highly accurate processing results by deriving the final answer not only from a single determination result but also from multiple determination results. 【0090】 Furthermore, according to the embodiment, the processing unit 1012 fixes the processing result to the second state if the Nth (N is a natural number) determination result of the determination unit 1011 for the wireless tag 700 is the first state, and the N+1th determination result of the determination unit 1011 is the second state due to insufficient information based on radio waves. The fact that the wireless tag 700 is in the second state due to insufficient information based on radio waves suggests that the wireless tag 700 is in the second state with a high probability, and the first state obtained on the Nth attempt was a misdetermined state. Therefore, even if the communication device 10 according to the embodiment misdetermines the first state when measured near the inventory shelf where the article 600 with the wireless tag 700 attached is stored, if the measurement is performed away from the inventory shelf, the processing result for the wireless tag 700 that was misdetermined as the first state can be fixed to the second state. Thus, the communication device 10 according to the embodiment can suppress the effects of misdetermined states and output highly accurate processing results. 【0091】 Furthermore, according to the embodiment, the processing unit 1012 counts up the first flag when the Nth determination result of the determination unit 1011 is the first state and the N+1th determination result of the determination unit 1011 is the second state in which there is no shortage of information based on radio waves. It also counts up the second flag when the Nth determination result of the determination unit 1011 is the second state and the N+1th determination result of the determination unit 1011 is the first state. The processing unit 1012 compares the count value of the first flag with the count value of the second flag and outputs a processing result indicating the first state if the count value of the first flag is greater than the count value of the second flag. It outputs a processing result indicating the second state if the count value of the first flag is not greater than the count value of the second flag. As a result, even if the determination result differs each time a measurement is taken to determine whether the device is inside or outside the area, the communication device 10 according to the embodiment can output the state with the higher count value as the processing result, thereby suppressing the effects of misjudgment and outputting a highly accurate processing result. 【0092】 Furthermore, according to this embodiment, the determination unit 1011 uses machine learning to determine the state of the wireless tag 700. By actually acquiring a large amount of tag data at a site such as a warehouse, generating a learning model using this large amount of tag data, and making determinations using the generated learning model, highly accurate determinations can be made. 【0093】 <Other variations, etc.> In the above embodiment, the communication device 10 includes an inference unit 500, and it is determined whether the wireless tag 700 is within a predetermined area by inputting tag data to the inference unit 500. The determination of whether the wireless tag 700 is within a predetermined area may be performed by the reader device 100 without using the inference unit 500. For example, the processor 101 of the reader device 100 may execute a machine learning program to determine whether the wireless tag 700 is within a predetermined area. In this case, the third connection interface 107 of the reader device 100 and the inference unit 500 may be omitted from the communication device 10. 【0094】 Furthermore, the determination of whether the wireless tag 700 is within a predetermined area may be performed without using AI (Artificial Intelligence) technology such as machine learning. For example, the processor 101 of the reader 100 may determine whether the wireless tag 700 is within a predetermined area by comparing the phase difference of the tag data with a threshold. By replacing the ACT20 process in the process described with reference to Figure 6 with the phase difference determination process described below, a modified version can be constructed in which the determination is made by comparing the phase difference with a threshold. 【0095】 Figure 11 is a flowchart showing the phase difference determination process of a communication device according to a modified example. When the phase difference determination process is started (start), the communication device 10 determines whether there is insufficient data (ACT61). Specifically, the processor 101 of the reader device 100 reads the tag data related to the wireless tag 700 to be determined from the storage 104 and determines whether there is insufficient data. 【0096】 If there is no data shortage (ACT61, No), the communication device 10 determines whether the phase difference is greater than or equal to a threshold (ACT62). Specifically, the processor 101 of the reader 100 determines whether the phase difference obtained from the tag data is greater than or equal to a predetermined threshold. 【0097】 If the phase difference is greater than or equal to the threshold (ACT62, Yes), the communication device 10 determines that it is within the region (ACT63). 【0098】 If there is insufficient data during the processing of ACT61 (ACT61, Yes), and if the phase difference is not above the threshold during the processing of ACT62 (ACT62, No), the communication device 10 determines that it is outside the range (ACT64). 【0099】 When the processing of ACT63 is completed, and when the processing of ACT64 is completed, the communication device 10 saves the determination result (ACT65). Specifically, the processor 101 of the reading device 100 controls the storage 104 to save the determination result. 【0100】 Once the ACT65 process is complete, the phase difference determination process shown in Figure 11 is terminated (end). 【0101】 When the reading device 100 is configured to perform phase difference determination processing in this manner, the third connection interface 107 of the reading device 100 and the inference unit 500 of the communication device 10 can be omitted. In other words, by configuring the reading device 100 to perform phase difference determination processing, the reading process of the communication device 10 can be performed without a configuration for executing machine learning. Therefore, the cost of the communication device 10 can be reduced. 【0102】 Furthermore, the above embodiment described an example where tag data is acquired while moving one antenna 300. Other configurations are also acceptable as long as tag data can be acquired while changing the relative position between the antenna 300 and the wireless tag 700. For example, multiple antennas may be placed at different positions, and the system may be configured to acquire tag data using multiple antennas. Alternatively, for example, one antenna 300 may be fixed, and a container CON may be moved, and the system may be configured to acquire tag data while moving the container CON. 【0103】 Furthermore, the above embodiment was described as an example in which a user pushes a cart equipped with the communication system 1 around a warehouse where shelves containing many items 600 with wireless tags 700 attached are lined up, and stores the desired items 600 in container CON. The situations in which the communication system 1 is used are not limited to this. For example, the communication system 1 may be fixed to the floor, and the shelves containing many items 600 with wireless tags 700 attached may move. In this example, the user stands near the communication system 1 fixed to the floor and picks up the items 600 from the shelves that move close by. 【0104】 Furthermore, the above embodiment described the process by which the out-of-bounds confirmation flag is set. The communication device 10 may be configured to reset the out-of-bounds confirmation flag when a certain amount of time has elapsed since it was set, or when a certain number of measurements have been taken since it was set. 【0105】 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] 【0106】 1...Communication system, 10...Communication device, 100...Reader, 200...Driver, 300...Antenna, 400...Terminal, 500...Inference machine, 600...Item, 700...Wireless tag, 101...Processor, 102...ROM, 103...RAM, 104...Storage, 105...First connection interface, 106...Second connection interface, 107...Third connection interface, 108...High-frequency front end, 109...Digital amplitude modulation unit, 110...DA converter 111...AD conversion unit, 112...Demodulation unit, 113...Bus, 1011...Determination unit, 1012...Processing unit, 201...Processor, 202...ROM, 203...RAM, 204...Connection interface, 205...Drive unit, 206...Home position sensor, 211...Rotation axis, 212...Rail, 213...Moving stage, CHA...Chassis, WHE...Wheel, HDL...Handle, CAS...Case, CON...Container, 81...First area, 82...Second area.

Claims

[Claim 1] An antenna that receives radio waves from wireless tags, A determination unit determines, based on information from multiple radio waves received by the antenna, whether the wireless tag is in a first state where it is in a first region, or in a second state where it is in a second region that does not include the first region, under multiple conditions where the relative positions of the wireless tag and the antenna are different. A processing unit that outputs a processing result indicating whether the wireless tag is in a first state or a second state, based on multiple determination results from the determination unit regarding the wireless tag, A communication device equipped with the following features. [Claim 2] The communication device according to claim 1, wherein the processing unit fixes the processing result to the second state when the Nth determination result (where N is a natural number) of the determination unit for the wireless tag is the first state, and the N+1th determination result of the determination unit is the second state due to insufficient information based on radio waves. [Claim 3] The processing unit, with respect to the wireless tag, If the Nth determination result (where N is a natural number) from the determination unit is the first state, and the N+1th determination result from the determination unit is the second state, where there is no shortage of information based on radio waves, then the first flag is counted up. If the Nth determination result of the determination unit is the second state, and the N+1th determination result of the determination unit is the first state, the second flag is counted up. The count value of the first flag and the count value of the second flag are compared, and if the count value of the first flag is greater than the count value of the second flag, the processing result indicating the first state is output, and if the count value of the first flag is not greater than the count value of the second flag, the processing result indicating the second state is output. The communication device according to claim 1. [Claim 4] The communication device according to claim 1, wherein the determination unit uses machine learning to determine the state of the wireless tag. [Claim 5] The communication device according to claim 1, wherein the determination unit compares a phase difference calculated from the information based on the plurality of radio waves with a threshold value in determining the state of the wireless tag. [Claim 6] In the processor of the communication device, Under multiple conditions where the relative positions of the wireless tag and the antenna communicating with the wireless tag are different, the system determines, based on information derived from multiple radio waves received by the antenna, whether the wireless tag is in a first state where it is in a first region, or a second state where it is in a second region that does not include the first region. Based on the results of multiple determinations regarding the state of the wireless tag, the state of the wireless tag is determined. Control program for communication devices.

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