JP5685511B2 - RFID tag communication device - Google Patents

Description

  Embodiments described herein relate generally to an RFID tag communication apparatus that reads information from an RFID (Radio Frequency IDentification) tag in a contactless manner.

  Conventionally, a non-contact RFID tag communication apparatus can read a plurality of RFID tags at a time. Since this non-contact RFID tag communication apparatus can read a plurality of RFID tags, even when it is desired to read only one RFID tag from among a plurality of RFID tags, it is confirmed which RFID tag has been read. It may be difficult. In order to prevent this, there is an RFID tag communication device that identifies an RFID tag attached to a desired object in advance and links and registers the RFID tag, the object, and an image of the object.

Japanese Patent No. 3618801

  The problem to be solved by the present invention is to provide an RFID tag communication device that can easily and reliably match a target product and an RFID tag attached to the product even from a remote location.

In order to solve the above problems, the RFID tag communication apparatus of the embodiment, the radiator having a first opening formed in the first opening area, provided apart from the radiator, the first A ground plane having a second opening formed with a second opening area smaller than the opening area, an antenna having directivity having a maximum gain in a specific direction, and an optical axis in the maximum gain direction of the antenna An optical system having a laser pointer that coincides with the axis and emits visible light through the first opening after the second opening, a wireless unit that communicates with the RFID tag through the antenna, and the antenna is an RFID tag JP received signal level holding means for holding the received signal level when the response signal is received from the notification means the received signal level notifying information read up to the RFID tag, in that it comprises It is set to.

BRIEF DESCRIPTION OF THE DRAWINGS Schematic explanatory drawing which shows the usage example of the article | item management system in the article | item management warehouse using the RFID tag communication apparatus of one Embodiment. It is a figure showing an example of the receiving antenna structure of this embodiment, (a) is a top view, (b) is a side view. The figure showing an example of the directivity characteristic of the receiving antenna of this embodiment. The block diagram showing the outline of the RFID tag communication apparatus of 1st Embodiment. The block diagram for demonstrating the radio | wireless part of 1st Embodiment. The flowchart for demonstrating operation | movement of 1st Embodiment. The flowchart for demonstrating operation | movement of 2nd Embodiment. The block diagram showing the outline of the RFID tag communication apparatus of 3rd Embodiment. Explanatory drawing showing the rotation part of this embodiment. The flowchart for demonstrating operation | movement of 3rd Embodiment. The table showing an example of the 2nd storage part of a 3rd embodiment.

  Hereinafter, the RFID tag communication apparatus of this embodiment will be described with reference to the drawings.

<First Embodiment>
FIG. 1 is a schematic configuration diagram illustrating an example of use of an RFID tag communication apparatus 1 according to an embodiment.

  For example, RFID tags 5 are attached to a plurality of articles 3 arranged on the shelf 2. The RFID tag 5 stores information on the article 3.

  The portable terminal device 6 reads the tag information of the article 3, images the article, and manages it. The portable terminal device 6 includes, for example, a transmission antenna 15, a reception antenna 16, and a camera 20 that is an optical system. The user picks up an image while checking the article 3 with the mobile terminal device 6 to obtain information on the RFID tag 5.

  FIG. 2 shows an example of the configuration of the receiving antenna 16 and the camera 20. The receiving antenna 16 includes a radiator 41 having a radiator hole 42 in a substantially central portion, a ground plate 43 having a ground plate hole 44 in a substantially central portion, and a spacer 45 for fixing the radiator 41 and the ground plate 43. Radiator 41 and ground plane 43 are made of a metal plate such as iron or aluminum.

  A gap between the radiator 41 and the ground plane 43 separated by the spacer 45 is, for example, an air layer 46. The spacer 45 is made of a material that does not have an electrical action, such as polystyrene foam. The ground plane 43 is connected to the ground (GND) of the receiving antenna 16 of FIG. The feed point 47 of the radiator 41 is connected to the signal line of the antenna terminal 53.

  A casing 48 is provided to protect the receiving antenna 16. A housing hole 49 is formed at a portion where an axis passing through the radiator hole 42 and the main plate hole 44 intersects the housing 48.

  The camera 20 is installed so that an axis passing through the radiator hole 42, the ground plane hole 44, and the housing hole portion 49 coincides with the central optical axis α of the camera 20. A transparent member may be provided in each of the three holes, that is, the radiator hole 42, the base plate hole 44, and the housing hole 49.

  It is desirable that the diameter of the hole is the smallest in the main plate hole 44, and is increased in the order of the radiator hole 42 and the housing hole 49. By increasing the diameter of the hole as the distance from the camera 20 increases, the field of view obtained by the camera 20 can be widened.

  FIG. 3 is a diagram showing the directivity characteristics of the receiving antenna 16. Here, description will be made assuming that the direction of the central axis of the antenna 10 indicated by the arrow P is the maximum gain direction of the receiving antenna 16.

  The receiving antenna 16 has a directivity characteristic of S as shown in FIG. 3, and the maximum gain direction is the maximum gain direction axis P. The maximum gain direction axis P coincides with the approximate center of the radiator hole 42 and the approximate center of the main plate hole 44.

  The mobile terminal device 6 arranges the camera 20 behind the main plate hole 44, for example. The center optical axis α of the camera 20 is substantially coincident with the maximum gain direction axis P of the antenna 10. As a result, the reading direction of the RFID tag 5 and the center of the captured image of the camera 20 substantially coincide.

  Although the description has been given using the camera 20 as the optical device, the optical device is not limited to the imaging device, and may be a visible light irradiation device such as a laser pointer 22. Moreover, you may use both adjacently.

  The receiving antenna 16 may be provided with two feeding points 47 and a signal supplied to one feeding point may be shifted by a predetermined phase and supplied to the other feeding point, or a radiator 41 may be provided with a perturbing element. Thereby, the polarization characteristic of the receiving antenna 16 can be made circularly polarized.

  In the present embodiment, at least the configuration of the receiving antenna 16 only needs to be as shown in FIGS. 3 and 2, and the configuration of the transmitting antenna 15 is not limited.

  FIG. 4 is a schematic block diagram of the RFID tag communication apparatus 1 according to the first embodiment. A display unit 11 such as a display or a buzzer for notifying the user of a state, an input unit 12 for an operation input by the user, an interface unit 13 for communicating with an external device, and a camera for grasping a reading direction 20, there is a wireless unit 14 that communicates with the RFID tag 5. The display unit 11, the input unit 12, the interface unit 13, the wireless unit 14, and the camera 20 are all connected to the control unit 19. The radio unit 14 is also connected to the transmission antenna 15 and the reception antenna 16.

  The control unit 19 includes a CPU, a ROM, a RAM, and the like, and includes a transmission output setting unit 31 that sets a transmission output for transmitting radio waves to the wireless unit 14, and a received signal level when the response signal of the RFID tag 5 is received. Received signal level holding means 32, target discrimination holding means 33 for discriminating a target RFID tag 5 when reading a plurality of RFID tags 5, ID information of the read RFID tag 5 and an image obtained from the camera 20 A first storage unit 34 for storing information and the like, and a captured image holding unit 35 for holding a captured image are provided.

  FIG. 5 is a block diagram for explaining the configuration of the wireless unit 14. In the case of the RFID tag 5 having no battery, the transmission antenna 15 outputs an electromagnetic wave from the transmission unit 36 under the control of the control unit 19 to activate the RFID tag 5. The reflected wave signal of the RFID tag 5 is received by the receiving antenna 16. The detected electromagnetic wave signal is demodulated by the receiving unit 37 and input to the control unit 19.

  FIG. 6 is a schematic flowchart of the first embodiment. In the above configuration, the user images the mobile terminal device 6 in the direction of the article. The image of the article displayed on the display unit 11 and the information of the RFID tag 5 attached to the article 3 are confirmed. If they match, the image is stored in the first storage unit 34.

  When the user turns on the RFID tag communication apparatus 1 (S101), the control unit 19 operates the camera 20 to start imaging (S102).

  Still images are taken at predetermined intervals and transmitted to an external device via the display unit 11 or the interface unit 13. The transmitted image is displayed on the display unit 11. The user looks at the display image on the display unit 11 and confirms whether the reading direction of the RFID tag communication device 1 is the direction of the target article 3 and the RFID tag 5 attached thereto. When the laser pointer 22 is provided, the control unit 19 operates the laser pointer 22 to start visible light irradiation. Further, the user looks at the portion irradiated with visible light and confirms whether the reading direction of the RFID tag communication device 1 is the direction of the target article 3 and the RFID tag 5 attached thereto.

  When the user inputs reading start to the input unit 12, the control unit 19 sets a predetermined transmission output to the wireless unit 14 (S103).

  In step S104, when there is an RFID tag 5 reading start input (Yes in S104), the number of readings i of the RFID tag 5 is reset (S105). When there is no RFID tag 5 reading start input (No in S104), the RFID tag 5 The reading of the RFID tag 5 is started after waiting for the reading start input.

  In step S106, the read ID information of the RFID tag 5 is held, and the received signal level is held in the received signal level holding means 32. Further, the image captured by the camera 20 is retained in the captured image retaining means 35.

  After reading the RFID tag 5 for a predetermined time, the electromagnetic wave output is stopped and the reading is stopped (S107).

  When the number of readings of the RFID tag 5 is 0 (Yes in S108), 1 is added to the number of readings i (S109), and when the number of readings i of the RFID tag 5 has not reached n times, the process returns to Step S106. (No in S110). Alternatively, when the number of readings i of the RFID tag 5 has reached n times (Yes in S110), the number of readings of the RFID tag 5 and the fact that the reading has been performed correctly are displayed in step S111, and the series of operations is terminated.

  If the number of read RFID tags 5 is not zero, the process proceeds to step S112 (No in S108).

  When the number of read RFID tags 5 is one, the process proceeds to step S113 (Yes in S112). The reading of the RFID tag 5 attached to the target article 3 is determined, and the ID information of the read RFID tag 5 and the captured image are associated with each other and stored in the first storage unit 34. In step S111, the number of read RFID tags 5 and information indicating that the reading has been correctly performed are displayed, and the series of operations is terminated.

  If the number of RFID tags read is two or more, the process proceeds to step S114 (No in S112). The control unit 19 extracts the RFID tag 5 having the highest received signal level among the received signal level holding means 32. In step S115, the ID information read from the extracted RFID tag 5 and the captured image are associated with each other and stored in the first storage unit 34.

  In step S111, the number of read RFID tags 5 and information indicating that the reading has been correctly performed are displayed, and the series of operations is terminated.

  As described above, in the first embodiment, the RFID tag reading direction can be easily and accurately known by matching the central optical axis α of the camera 20 with the maximum gain direction axis P of the antenna 10. Usability is dramatically improved. Further, even when a plurality of RFID tags are read, the target RFID tag can be determined and detected.

<Second Embodiment>
Next, a second embodiment will be described with reference to FIG. The difference from the first embodiment is that the transmission output is increased or decreased according to the number of RFID tags 5 read. By increasing or decreasing the transmission output, an optimal transmission output can be obtained, and the target article 3 and the RFID tag 5 attached to the article 3 can be more accurately identified. Even when the RFID tag 5 cannot be read, the transmission output is increased or decreased and reading is performed up to n times. When the number of RFID tags 5 to be read is large, the one with the maximum received signal level can be selected.

  FIG. 7 is a flowchart. The same parts as those in the first embodiment are denoted by the same reference numerals and the description thereof is omitted.

  When there is an RFID tag 5 reading start input (Yes in S104), the output increase number i1 and output decrease number i2 of the RFID tag 5 are reset (S204), and reading of the RFID tag 5 is started (S205). When there is no RFID tag 5 reading start input (No in S104), reading of the RFID tag 5 is started after waiting for the RFID tag 5 reading start input (S205).

  The output increase number i1 and the output decrease number i2 of the RFID tag 5 are the number of times the transmission output is increased or decreased according to the number of readings of the RFID tag 5. The output increase number i1 indicates the number of times that the transmission output is sequentially increased when the RFID tag 5 cannot be read, and the output decrease number i2 indicates the number of times that the transmission output is sequentially decreased when a plurality of RFID tags 5 are read.

  In step S205, an electromagnetic wave is output to start reading the RFID tag 5, and the read received signal level and captured image are held.

  In step S206, after reading for a predetermined time, the output of electromagnetic waves is stopped.

  If the number of read RFID tags 5 is zero, the process proceeds to step S208 (Yes in S207). When the number of read RFID tags 5 is one or more, the process proceeds to step S215 (No in S207).

  In step S208, 1 is added to the output increase number i1, and the process proceeds to step S209. When the output increase number i1 of the RFID tag 5 reaches the maximum reading number n1 of the RFID tag 5, the process proceeds to step S210 (Yes in S209), and in step S210, the reading number of the target RFID tag 5 and the fact that the reading has been correctly performed are displayed. To do.

  When the output increase number i1 of the RFID tag 5 has not reached n times, the process proceeds to step S211 (No in S209). The number of RFID tags read is displayed on the display unit 11 (S211), and a message is displayed to ask the user whether to increase the transmission output (S212). If there is an input for requesting an increase in transmission output (Yes in S213), the transmission output is increased (S214), and the process returns to step S205 again. By the transmission output setting means 31, the control unit 19 increases the transmission output by a predetermined value and reads the RFID tag 5 again. The transmission output is increased up to n1 times.

  When the number of read RFID tags 5 is one or more, the process proceeds to step S215 (No in S207). If the number of read RFID tags 5 is one, the process proceeds to step S216 (Yes in S215).

  When the output increase number i1 of the RFID tag 5 reaches n1, the number of readings of the target RFID tag 5 and the fact that the reading is correctly performed are displayed in step S210.

  When the number of read RFID tags 5 is one, the process proceeds to step S216 (Yes in S215). In step S216, the ID information and image information of the read RFID tag 5 are associated with each other and stored in the first storage unit 34. In step S210, the number of read RFID tags 5 is displayed on the display unit 11, and the target information is displayed. The number of readings of the RFID tag 5 and the fact that the reading has been correctly performed are displayed, and the series of operations is terminated.

  If the number of read RFID tags 5 is two or more, the process proceeds to step S217 (No in S215), and 1 is added to the number of output reductions i2 of the RFID tag 5, and the process proceeds to step S218. When the number of output reductions i2 of the RFID tag 5 reaches the maximum n2 times, the process proceeds to step S219 (Yes in S218).

  In step S219, the RFID tag 5 having the maximum received signal level is extracted from the received signal level holding means. In step S220, the ID information read from the extracted RFID tag 5 and the captured image are associated with each other and stored in the first storage unit 34. In step S210, the number of RFID tags 5 read is displayed on the display unit 11. Further, a message indicating that the target RFID tag 5 has been read correctly is displayed, and the series of operations is terminated.

  When the number of output reductions i2 of the RFID tag 5 has not reached the maximum n2 times (No in S218), the number of reading of the RFID tag 5 is displayed (S221). In step S222, the display unit 11 is displayed asking whether to reduce the transmission output.

  In step S223, when there is an input to reduce the transmission output from the input unit 12, the process proceeds to step S224 (Yes in S223).

  The controller 19 lowers the transmission output by the transmission output setting means 31 and reads the RFID tag 5 again (S224). The transmission output is reduced up to n2 times.

  If there is no input for lowering the transmission output from the input unit 12 (No in S223), reading is started again without lowering the transmission output (S205).

  In FIG. 7, the user is inquired about the change of the transmission output, but may be automatically changed.

  Also in the second embodiment described above, by matching the central optical axis α of the camera 20 with the maximum gain direction axis P of the antenna 10, the RFID tag reading direction can be easily and accurately known, and the usability is greatly improved. Improve. Further, even when a plurality of RFID tags are read, the target RFID tag can be determined and detected.

  Further, by optimizing the transmission output in this way, the target article 3 and the tag attached to the article 3 can be more accurately identified.

<Third Embodiment>
Next, a third embodiment will be described with reference to FIGS. The third embodiment differs from the first embodiment in two points: the structure of the antenna and the movement of the antenna and the camera 20.

  FIG. 8 is a diagram illustrating an example of the configuration of the RFID tag communication apparatus 1 according to the third embodiment. The difference between FIG. 8 and FIG. 4 is that the antenna is a transmission / reception antenna 51 and includes a first rotating unit 62, a second rotating unit 63, and a second storage unit 71. The second storage unit 71 stores the read ID information, received signal level, and captured image of the RFID tag 5.

  The wireless unit 14 is connected to the transmission / reception antenna 51 via the directional coupler 52.

  FIG. 9 is a diagram illustrating an example of the rotating unit. The first rotating unit 62 rotates the transmission / reception antenna 51 around the vertical axis q of the transmission / reception antenna 51. The second rotating unit 63 rotates the transmission / reception antenna 51 and the camera 20 around the horizontal axis r of the transmission / reception antenna 51 and the camera 20. The first rotating unit 62 and the second rotating unit 63 are rotationally driven by a motor in order to detect a target article. It also has functions such as rotation angle detection.

  FIG. 10 is a diagram illustrating an example of a flowchart of the third embodiment. The same parts as those in the first and second embodiments are denoted by the same reference numerals, and the description thereof is omitted. The reading angles of the first rotating unit 62 and the second rotating unit 63 are denoted as φ1 and φ2, respectively.

  After the transmission output is set in step S103, the reading angles are reset to φ1 = 0 and φ2 = 0, respectively, in step S304.

  In step S305, an electromagnetic wave is output, and reading of the RFID tag 5 is started when both φ1 and φ2 are 0 degrees. When the RFID tag 5 is read, the ID information, the received signal level, and the captured image of the read RFID tag 5 are stored in the second storage unit 71.

  In step S306, after the RFID tag 5 is read for a predetermined time, the electromagnetic wave output is stopped.

  In steps S307 to S310, the reading angles φ1 and φ2 are both changed by 5 degrees, and the RFID tag 5 is read up to 180 degrees for both φ1 and φ2. The second storage unit 71 stores data such as the example of FIG. Although not shown, the captured image may be captured at an angle that is half the angle at which the reading operation is performed.

  When φ1 reaches 180 degrees (Yes in S307), φ1 is reset (S308).

  When φ2 reaches 180 degrees (Yes in S309), φ2 is reset (S310).

  Until φ1 reaches 180 degrees in step S307 (No in S307), φ1 is increased by 5 degrees (S313). Thereafter, the process returns to step S305.

  Until φ2 reaches 180 degrees in step S309 (No in S309), φ2 is increased by 5 degrees (S314). Thereafter, the process returns to step S305.

  Steps S313 and S314 are repeated until both φ1 and φ2 are 180 degrees or more. When both φ1 and φ2 are 180 degrees or more, the process proceeds to step S311.

  In step S311, the control unit 19 detects the maximum reception level from the reception levels stored in the second storage unit 71 for each read RFID tag 5, and determines φ1 and φ2 at the maximum reception level as the first reception level. 1 storage unit 34. If there are a plurality of angles at which the maximum reception level is detected, the central angle is calculated and stored. For example, for the RFID tag with RFID tag ID = ID1 in FIG. 11, the control unit 19 detects from the data in the second storage unit 71 that the received signal level is the maximum value when φ1 = φ1a and φ2 = φ2a. Then, it is determined that the RFID tag with ID = ID1 is in this direction. Further, an image is captured by the camera 20, and an image when φ1 = φ1a and φ2 = φ2a is associated with an RFID tag with ID = ID1. The RFID tag with ID = ID1 and the article 3 to which the RFID tag is attached are determined to be the article 3 having an image near the center of the image. These pieces of information are stored in the second storage unit 71.

  Similarly, for the RFID tag with RFID tag ID = ID2 in FIG. 11, the control unit 19 determines from the data in the second storage unit 71 that φ1 = φ1b1, φ2 = φ2b, and φ1 = φ1b2, φ2 = φ2b. Sometimes, it is detected that the received signal level is the maximum value, and the RFID tag with ID = ID1 is determined to be in the direction of φ1 = (φ1b1 + φ1b2) / 2, φ2 = φ2b, and the image at this time and ID = ID2 It is tied with the RFID tag. If an image with an angle of φ1 = (φ1b1 + φ1b2) / 2 and φ2 = φ2b is not captured, an image with an angle of φ1 = φ1b1, φ2 = φ2b, or an image with an angle of φ1 = φ1b2, φ2 = φ2b It may be tied.

  In step S312, the number of RFID tags 5 read, the ID information of the read RFID tags 5, and φ1 and φ2 at the detected maximum reception level are displayed on the display unit 11 or from the interface unit 13 to the external device. To end the series of operations.

  As a result, the ID information, the received signal level, and the captured image of the RFID tag 5 that has been read are stored in the first storage unit 34 for each angle of φ1 and φ2. Although not shown, the captured image may be captured at an angle that is half the angle at which the reading operation is performed.

  The control unit 19 detects the maximum reception level from the reception levels stored in the second storage unit 71 for each read RFID tag 5, and first stores φ1 and φ2 at the maximum reception level. Stored in the unit 34. If there are a plurality of angles at which the maximum reception level is detected, the central angle is calculated and stored. FIG. 11 shows the received signal level of the RFID tag 5 with ID = ID1 at each angle, with the vertical item in the table as φ1 and the horizontal item in the table as φ2 for the RFID tag 5 with ID ID1. It is. The received signal level value is a relative value and has no unit. The larger the received signal level value, the higher the received signal level. In FIG. 11, the angle column in which the RFID tag 5 with ID = ID1 could not be read is blank (or 0). In FIG. 11, an example is similarly shown for the RFID tag 5 with ID = ID2 and the RFID tag 5 with ID = ID3.

  In FIG. 11, when the ID of the RFID tag 5 is ID1, the control unit 19 detects from the data in the second storage unit 71 that the received signal level is the maximum value when φ1 = φ1a and φ2 = φ2a. . In step S312, it is determined from the detection result that the RFID tag 5 with ID = ID1 is in the direction of φ1 = φ1a and φ2 = φ2a, and the image when φ1 = φ1a and φ2 = φ2a and the RFID with ID = ID1 Linking with tag 5 is performed. The RFID tag 5 of ID = ID1 and the article 3 to which the RFID tag 5 is attached are determined to be the article 3 of the image near the center of the image, and the information is stored in the first storage unit 34.

  In the above description, the example in which the RFID tag 5 is read by the transmission / reception antenna 51 and the captured image is captured by the camera 20 for each angle of φ1 and φ2 is shown. However, the direction of the RFID tag 5 of each ID, that is, the maximum reception level is shown. After detecting φ1 and φ2 at the time, the camera 20 may be rotated in the direction of the RFID tag 5 to capture an image and capture the captured image.

  As described above, the third embodiment can detect the reception level at the angles of φ1 and φ2 for each read RFID tag, know the position of the RFID tag, and an article with the RFID tag attached thereto. 3 images can be linked, and usability is greatly improved.

  In addition, regarding the detected RFID tag 5, the control unit 19 sets the angles to φ1 and φ2 by the first rotating unit 62 and the second rotating unit 63, and captures the ID information of the RFID tag 5, φ1, φ2, and the camera 20. By displaying the obtained image on the display unit 11, in addition to the ID information of the RFID tag 5, the user can be informed of the direction, position, and image of the article 3 to which the RFID tag 5 is attached. In addition to displaying on the display unit 11, these pieces of information may be transmitted to the external device via the interface unit 13 and displayed on the external device. Further, the laser pointer 22 may be irradiated with visible light to notify the user of the direction and position.

  As described above, by matching the optical axis of imaging or visible light irradiation with the maximum gain direction axis P of the antenna, the target product and the RFID tag attached to the product can be easily and reliably matched even from a remote location. It is possible to improve the usability. Further, even when a plurality of RFID tags are read, the target RFID tag can be determined and detected.

  Although several embodiments have been described above, these embodiments are presented as examples, and are not intended to limit the scope of the invention. The novel embodiment can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1 ... RFID tag communication apparatus 5 ... RFID tag 6 ... Portable terminal device 10 ... Antenna 11 ... Display part 12 ... Input part 13 ... Interface part 14 ... Wireless part 15 ... Transmission antenna 16 ... Reception antenna 19 ... Control unit 20 ... Camera 22 ... Laser pointer 31 ... Transmission output setting means 32 ... Reception signal level holding means 33 ... Object discriminating / holding means 34 ... first storage unit 35 ... captured image holding means 36 ... transmitting unit 37 ... receiving unit 38 ... transmitting antenna terminal 39 ... receiving antenna terminal 51 ... Transmission / reception antenna 52 ... Directional coupler 53 ... Antenna terminal 61 ... Rotating part 62 ... First rotating part 63 ... Second rotating part 71 ... Second storage part P・ ・ Maximum gain direction axis S ・ ・ ・ Directional characteristic α ・ ・Central optical axis q · · · vertical axis r · · · horizontal axis

Claims (5)

A radiator having a first opening formed with a first opening area, and a second opening formed with a second opening area that is spaced apart from the radiator and is smaller than the first opening area An antenna with directivity having a maximum gain in a specific direction,
An optical system having a laser pointer whose optical axis coincides with the axis of the maximum gain direction of the antenna and irradiates visible light through the first aperture next to the second aperture ;
A wireless unit that communicates with the RFID tag via the antenna;
Received signal level holding means for holding a received signal level when the antenna receives a response signal from the RFID tag;
Notification means for notifying the read information of the RFID tag having the maximum received signal level;
RFID tag communication apparatus comprising:   The RFID tag communication apparatus according to claim 1, wherein the optical system further includes an imaging unit. The target determination storage means for storing in association with the first storage unit read information and the image information of the imaging unit prior Symbol received signal level is largest RFID tag,
The RFID tag communication apparatus according to claim 2, further comprising: A rotating part for rotating the antenna;
A second storage unit that associates and stores the rotation angle of the antenna, RFID tag information read by the antenna, and the received signal level of the antenna;
A direction detection unit that detects a rotation angle of the antenna for which the received signal level is maximum for each RFID tag read by the antenna;
The RFID tag communication device according to claim 1, further comprising: The optical system includes an imaging unit;
A third storage unit that associates and stores the read information of the RFID tag, the rotation angle detected by the direction detection unit, and imaging information at the rotation angle detected by the direction detection unit; The RFID tag communication device according to claim 4 .

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