JP5158574B2 - Wireless communication system, wireless communication system, RFID label printer, and RFID inspection system - Google Patents

Description

  The present invention relates to a wireless communication system, a wireless communication system, an RFID label printer, and an RFID inspection system that can perform good wireless communication by combining the polarization planes of both antennas when performing wireless communication between two antennas.

  When performing wireless communication between two antennas, it is conventionally known that good communication performance can be obtained if communication is performed with the polarization planes (or polarization directions) of both antennas being matched. Therefore, even in RFID systems that have been used in recent years in the manufacturing industry, logistics industry, etc., that is, systems that perform communication using electromagnetic waves between a reader / writer and an RFID tag, communication is performed with the same polarization plane between the reader / writer and the RFID tag. Is desirable for good communication.

  In this RFID system, there is a situation in which a reader / writer is placed at an arbitrary position for communication (reading and writing) with respect to the RFID tag. However, due to the polarization characteristics of the electromagnetic wave, the antenna on the reader / writer side and the RFID tag When a linear (linear) polarization antenna is used as the antenna, there is a problem that the communication distance varies greatly depending on the arrangement of the reader with respect to the RFID tag (angle between the antennas). Therefore, conventionally, the above problem has been solved by employing a circularly polarized antenna as the reader / writer side antenna (for example, see Patent Document 1).

  However, as described above, when a circularly polarized antenna is used as the reader / writer side antenna, the antenna becomes relatively large and requires a large area for installation. A new problem arises. In particular, in a printer capable of printing on a label incorporating an RFID tag (referred to herein as “RFID label printer”, see Patent Document 2), it is desirable to reduce the size of the reader / writer part. It is preferable to employ a linearly polarized antenna such as a dipole antenna.

  Even when a linearly polarized antenna such as a dipole antenna is employed, if communication can be performed with the polarization planes of both antennas on the RFID tag and reader / writer sides being matched, good communication performance can be obtained. Conventionally, however, no effort has been made to communicate with the plane of polarization.

JP 2007-208536 A

JP 2005-328259 A

  The present invention relates to a wireless communication system, a wireless communication system, and an RFID label printer that can perform wireless communication by adjusting the polarization planes of the two antennas so that the polarization planes of the two antennas are matched. And an RFID inspection system.

The present invention, in the first antenna and a wireless communication method for performing wireless communication with the second antenna, is disposed a slotted conductive member in the vicinity of the second antenna, the slotted conductive member By aligning the direction of the slot with the plane of polarization of the first antenna, it acts to match the plane of polarization of the first antenna and the second antenna.

The wireless communication system according to the present invention includes a first antenna, a second antenna, and a slotted conductive member disposed in the vicinity of the second antenna. By aligning the direction of the slot in the member with the polarization plane of the first antenna, it acts to match the polarization planes of the first antenna and the second antenna.

In addition, the RFID label printer according to the present invention includes a conveyance unit that conveys a plurality of RFID labels, a printing unit that prints on each RFID label, a second antenna included in each RFID label, and a wireless communication between the second antenna and the second antenna. A first antenna that performs communication; and a slotted conductive member that is disposed in the vicinity of the second antenna, and the direction of the slot in the slotted conductive member is offset from the first antenna. By matching with the wavefront, the polarization planes of the first antenna and the second antenna can be matched.

In addition, the RFID inspection system according to the present invention includes a transport unit that transports a plurality of RFID labels or a plurality of RFID inlets, and a first antenna that performs radio communication with a second antenna of each RFID label or each RFID inlet. have, an RFID test system for a communication inspection of RFID labels or RFID inlets, arranged a slotted conductive member in the vicinity of the second antenna, of the slots in the slotted conductive member By adjusting the direction to the polarization plane of the first antenna, the polarization planes of the first antenna and the second antenna can be matched.

  The slotted conductive member may be a metal plate or may be detachably disposed.

  Here, the description of the first antenna and the second antenna is merely a convenient expression for distinguishing both antennas. For example, when the first antenna is a transmitting antenna that transmits radio waves. The second antenna is a receiving antenna that receives the radio wave, but the transmission / reception relationship may be reversed.

  That is, the wireless communication system, the wireless communication system, the RFID label printer, and the RFID inspection system of the present invention perform wireless communication via the slotted conductive member when the polarization planes of the two antennas do not match. Thus, good wireless communication can be performed with the polarization planes of both antennas being combined.

  Here, polarization refers to a state in which radio waves have a specific vibration direction. When the wave of the electric field (the space of electric force generated between + and-due to voltage) is oscillating in the horizontal direction with respect to the ground, the horizontally oscillating wave is vertically polarized, The polarization plane is the direction of vibration when radio waves are radiated from the antenna. If the planes of polarization of ideal antennas deviate by 45 degrees, the reception level decreases by 3 db, and if they deviate by 90 degrees, they cannot be received. As described above, performing communication in a state where the plane of polarization is shifted causes a decrease in reception level and communication failure.

  As a method of matching the planes of polarization, it is conceivable to simply rotate one of the antennas physically so that the plane of polarization matches the antenna on the other side. However, this method requires a rotating mechanism, and this method cannot cope with the case where the direction of the antenna cannot be changed due to the installation space of the antenna.

  Therefore, the present inventor has found the present invention as a result of diligent research, and has enabled "polarization plane matching between antennas" by a simpler and less expensive method than the above physical method.

  That is, the greatest feature of the present invention is that the plane of polarization between the two antennas can be matched only by disposing a slotted conductive member in the vicinity of the second antenna. With this configuration, there is no need to rotate the antenna itself, and no special rotation mechanism is required. In addition, by simply introducing a slotted conductive member into the existing system, the polarization plane between the antennas It is very simple and inexpensive.

  Here, the slotted conductive member is a conductive member in which a slot which is an elongated hole is formed. What is necessary is just to arrange | position so that the slot direction (direction of the width direction of a slot) of this electroconductive member containing a slot may match the polarization plane of a 1st antenna. Specifically, for example, even if the polarization plane of the first antenna (transmission antenna) is in the vertical direction and the polarization plane of the second antenna (reception antenna) is in the horizontal direction, the slotted conductivity between both antennas. By arranging and communicating with the member slot oriented in the vertical direction, the polarization plane on the second antenna side acts to match the polarization plane on the first antenna side. As a result, even if the polarization planes between the two antennas are physically different, the polarization plane is adjusted and good communication can be performed with the polarization planes matched.

  The slotted conductive member may be a metal plate. The material of the slotted conductive member needs to be conductive at a minimum, but may be plated, for example. Further, the slotted conductive member may be detachably disposed. When the polarization planes of the first antenna and the second antenna are matched, it is not necessary to use the slotted conductive member. On the other hand, if the slotted conductive member is permanently installed, if the plane of polarization is matched between the two antennas, the slotted conductive member is rather harmful, that is, the plane of polarization between the two antennas is matched. Despite this, it will act so as not to match. Therefore, in the case where the slotted conductive member is permanently installed, the direction of the slot of the slotted conductive member is changed so that good communication can be performed even when the polarization planes between the two antennas are matched. A mechanism is required. However, if the slotted conductive member is detachably disposed, for example, manually disposed and removed, the above-described mechanism is not necessary.

  According to the present invention, when the planes of polarization of the first antenna and the second antenna do not match, the slotted conductive member is disposed in the vicinity of the second antenna, and the slotted conductive member The first antenna and the second antenna are configured to act so as to match the polarization planes. As a result, even if the planes of polarization between the two antennas are physically different, the plane of polarization between the two antennas can be adjusted easily and inexpensively, and good communication can be performed with the planes of polarization matched. Yes.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the wireless communication system and wireless communication system of the present invention can be realized as one function of the following RFID label printer and RFID inspection system. Therefore, in the following, individual descriptions of the wireless communication system and wireless communication system of the present invention will be given. Is omitted.

<One Embodiment of RFID Label Printer of the Present Invention>
An embodiment of the RFID label printer of the present invention will be described with reference to FIGS. FIG. 1 is an explanatory diagram for explaining the structure of an RFID label printer of the present invention, FIG. 2 is a block diagram showing electrical connection of each part of the RFID label printer of the present invention, and FIG. 3 is a polarization plane in the present invention. It is explanatory drawing for demonstrating conversion of these.

[RFID label printer structure]
The RFID label printer 1 shown in FIG. 1 is roughly configured as follows. That is, predetermined print information is printed on the surfaces of the RFID labels L1, L2, L3,... Temporarily attached to the base material D1 at predetermined intervals. At the same time, predetermined wireless tag information generated on the RFID label printer 1 side corresponding to the print information is sequentially written into an IC chip (not shown) provided in the RFID tag T using the reader / writer 7.

  More specifically, referring to FIG. 1, the RFID label printer 1 includes a reel 2, a platen roller 3, a thermal head 4 (printing means), an ink ribbon supply roller 5, an ink ribbon take-up roller 6, and a reader / writer 7. The first antenna 7a and the slotted metal plate 8 are included.

  The reel 2 is a support member that supports the RFID label original fabric D, in which the base material D1 temporarily attached with RFID labels L1, L2, L3,... . The platen roller 3 is a roller that rotates by driving a stepping motor 15 (conveying means), which will be described later, and functions to feed the substrate D1 in the conveying direction. The thermal head 4 is a print head that prints predetermined items on the RFID labels L1, L2, L3,..., And selectively heats a large number of resistance heating elements (not shown) arranged on the line. A predetermined matter is printed on the RFID labels L1, L2, L3,... By melting or sublimating the ink of the ribbon R.

  The ink ribbon supply roller 5 is a roller that supports the ink ribbon R wound in a roll shape so that the ink ribbon R can be fed out, and the ink ribbon take-up roller 6 is the ink ribbon R that has been fed out and that has been printed. It is a roller which supports so that winding is possible. The ink ribbon R fed out from the ink ribbon supply roller 5 is disposed so as to be in pressure contact with the thermal head 4.

  The RFID labels L1, L2, L3,... Are configured to include a second antenna 9 and an IC chip (not shown). As will be described later, the reader / writer 7 includes a first antenna 7a and a communication control unit 7b. The reader / writer 7 is configured to be able to perform wireless communication with the second antenna 9, and the predetermined tag information described above is provided to the IC chip. It is configured to be readable and writable.

  The slotted metal plate 8 is a conductive metal plate in which a slot S which is an elongated hole is formed, and is detachably disposed in the vicinity of the second antenna 9. In the present embodiment, the slotted metal plate 8 is used, but the present invention is not limited to this, and other shapes and materials can be applied including other conductive members. In addition, the slotted metal plate 8 is detachable, but it is not always necessary to be detachable. For example, if the structure is such that the direction of the slot of the slotted metal plate 8 can be changed, it is a fixed type. May be. In the present embodiment, the slotted metal plate 8 is disposed between the first antenna 7a and the second antenna 9 and on the surface side of the substrate D1, but the slotted metal plate If 8 is the vicinity of the 2nd antenna 9, it may be arrange | positioned in the back surface side of the base material D1 in FIG.3 (c), for example.

  When the slotted metal plate 8 is disposed in the RFID label printer 1, the direction of the width S of the slot S (see FIG. 3C) (hereinafter simply referred to as “the direction of the slot S”) varies. It is configured to be settable. Further, the slotted metal plate 8 is disposed in the vicinity of each RFID tag L1, L2, L3,. By disposing the slotted metal plate 8 in this manner, even when the polarization planes of the first antenna 7a and the second antenna 9 are different, the slotted metal plate 8 results in the polarization planes of both antennas. Are configured to communicate with each other. Details thereof will be described later with reference to FIG.

[Electrical connection of each part of RFID label printer]
Next, with reference to FIG. 2, the electrical connection of each part constituting the RFID label printer will be described. FIG. 2 is a block diagram showing the electrical connection of each part constituting the RFID label printer 1, and the electrical connection state is as shown below.

  That is, as shown in FIG. 2, the RFID label printer 1 includes a CPU 11, a ROM 13, a RAM 14, a stepping motor 15, a thermal head 4, a communication I / F 16, and a reader / writer 7 (abbreviated as R / W in FIG. 2). Are connected by a bus 12 from the CPU 11.

  The CPU 11 functions to comprehensively control each unit connected by the bus. The ROM 13 is a storage medium in which various programs for operating the RFID label printer 1 are stored. For example, the ROM 13 includes a flash memory. The RAM 14 is a storage unit that functions as various work areas such as developing various programs stored in the ROM 13. The stepping motor 15 is a motor for rotating the platen roller 3 to feed out the base material D1 from the RFID label original fabric D and to feed out a predetermined amount of ink ribbon R from the roll-shaped ink ribbon R. The communication I / F 16 is an interface for inputting print data output from an external device (not shown) and tag information stored in the RFID tag T.

[Basic operation of RFID label printer]
Next, basic operation processing by the RFID label printer 1 will be described. Under the overall control of the CPU 11, the stepping motor 15 is driven, and a predetermined amount of the substrate D1 is fed out from the RFID label original fabric D. The amount of feeding is stored in advance in the ROM 13 or the like, or is determined by detecting the leading edge of the RFID labels L1, L2, L3,. That's fine.

  The RFID labels L1, L2, L3,... Temporarily attached to the substrate D1 at the same time when the base material D1 is fed out are also fed out, and the fed out RFID labels L1, L2, L3,. In *, writing processing and printing processing are performed. These processes will be described using the RFID label L1 as an example.

  First, the fed RFID label L1 is written by the reader / writer 7. That is, a radio wave (with tag information) transmitted from the first antenna 7a of the reader / writer 7 is radiated toward the second antenna 9 of the RFID tag T included in the RFID label L1. At this time, good communication cannot be performed unless the planes of polarization of the first antenna 7a and the second antenna 9 are matched. Therefore, when the planes of polarization of the antennas 7a and 9 are not matched, a slotted metal plate is used. By attaching 8 to a predetermined place, the plane of polarization can be matched. Details thereof will be described later.

  Next, the RFID label L <b> 1 is printed by the thermal head 4. That is, in the thermal head 4, a predetermined location of the RFID label L1 is disposed immediately below, and the print information input via the communication I / F 16 is printed at the location. Specifically, under the control of the CPU 11, in the thermal head 4, resistance heating elements (not shown) arranged in a line are selectively energized and heated to melt or sublimate the ink on the ink ribbon R. Then, printing in the main scanning direction (width direction of the substrate D1) is performed on the RFID label L1. On the other hand, printing in the sub-scanning direction with respect to the RFID label L1, that is, the conveyance direction of the RFID label L1, is performed by rotating the platen roller 3 by driving the stepping motor 15 and feeding the substrate D1. At the time of this printing process, at the same time, a predetermined amount of the ink ribbon R is fed out from the ink ribbon R wound in a roll shape, and the ink ribbon R after printing is taken up by the ink ribbon take-up roller 6. It becomes.

[Polarization plane conversion processing]
Next, the polarization plane conversion process will be described with reference to FIG. FIG. 3 schematically shows the writing process to the RFID labels L1, L2, L3,... By the reader / writer 7. Furthermore, the relationship of the polarization plane in the case of performing wireless communication between the first antenna 7a and the second antenna 9 is shown, and FIG. (B) shows that the planes of polarization are not matched, and (c) shows that the planes of polarization of both antennas 7a and 9 are not matched, but the plane of polarization between the antennas 7a and 9 is matched by the slotted metal plate 8. Show the case.

  In the RFID label printer 1, the same type of RFID label original fabric D only needs to be set on the reel 2 each time, but sometimes a different type of RFID label original fabric D may be set on the reel 2. The polarization planes of the first antenna 7a and the second antenna 9 may not match. Specifically, as shown in FIG. 3A, when the first antenna 7a is set to have a polarization plane in the direction (R / W polarization plane) illustrated, each RFID label L1 to be conveyed If the planes of polarization of L2, L3,... Are in the direction shown in the figure (label plane of polarization), the planes of polarization between the antennas 7a and 9 match, so that good communication can be performed.

  On the other hand, as shown in FIG. 3B, the polarization plane of the first antenna 7a is the same as the direction shown in FIG. 3A, but the deviation of the RFID labels L1, L2,. When the wavefront is in the direction shown in the figure (label polarization plane), that is, in the direction of the RFID labels L1, L2,..., The polarization plane between the two antennas 7a, 9 is orthogonal and does not match. Communication cannot be performed, and communication may be disabled in some cases. In such a case, as a method of adjusting the plane of polarization, there is a method of simply changing the direction of the first antenna 7a. However, the RFID label printer 1 is downsized, and the direction of the first antenna 7a is changed. In many cases, it cannot be changed.

  Therefore, in the present invention, the polarization planes of both antennas 7a and 9 can be matched by a simple and inexpensive method even under the situation as shown in FIG. That is, as shown in FIG. 3C, the slotted metal plate 8 is simply disposed in the vicinity of the second antenna 9 so that the plane of polarization of the first antenna 7a and the plane of polarization of the second antenna 9 As a result, good communication can be performed in a state where the planes of polarization between the two antennas are matched.

  More specifically, as shown in FIG. 3C, the slotted metal plate 8 is disposed in the vicinity of the second antenna 9. At that time, the direction of the slot S of the slotted metal plate 9 is adjusted to the R / W polarization plane which is the polarization plane of the first antenna 7a. In this state, wireless communication is performed between the first antenna 7a and the second antenna 9. Then, as shown in FIG. 3C, the slot polarization plane of the slotted metal plate 8 and the label polarization plane are integrated to form a new adjustment polarization plane, which is an R / W polarization. Since the polarization plane is matched between the wavefront and the adjustment polarization plane, as a result, good communication can be performed with the polarization plane between the two antennas matched.

[Polarization conversion simulation]
As described above, in the RFID label printer 1 according to the present invention, the polarization plane is adjusted by the slotted metal plate 8 even when the polarization planes of the first antenna 7a and the second antenna 9 are different. However, since the present inventor actually performed a simulation using the product, the method and result will be described below with reference to FIGS.

  FIG. 4 is an explanatory diagram for explaining an example of a polarization plane conversion simulation using the slotted metal plate 8. FIG. 4A is an explanatory diagram of a coordinate system in the RFID inlet I1, and FIG. FIG. 5A is a view showing a state in which a slotted metal plate is added to the RFID inlet I1 described in FIG. 5A. FIG. 5A is an RFID inlet I1 without a slotted metal plate, and FIG. 5B is a slotted metal plate added. FIG. 6 is an explanatory diagram for explaining another embodiment of a simulation of polarization plane conversion using a slotted metal plate. FIG. 6 is a polar chart showing respective gains of the arrow A component in the case of the RFID inlet I1. (A) is explanatory drawing of the coordinate system in RFID inlet I2, (b) adds a slotted metal plate to RFID inlet I2 described in (a). FIGS. 7A and 7B show states of the arrow A component in the case of the RFID inlet I2 to which the slotted metal plate is not added, and FIG. 7B shows the gain of the arrow A component in the case of the RFID inlet I2 to which the slotted metal plate is added. It is a polar chart. In this simulation, the same slotted metal plate 8 was used for both the RFID inlet I1 and the RFID inlet I2.

  In both simulations of the RFID inlet I1 and the RFID inlet I2, the state where the RFID inlets I1 and I2 are set as shown in FIG. 4A or 6A, respectively, and FIG. As shown in FIG. 6B, when the slotted metal plate 8 is added and set to each of the RFID inlets I1 and I2, radio waves are transmitted from the reader / writer antenna (first antenna 7a), and the reflected waves The reception sensitivity was compared. This reception sensitivity was measured by the gain of the arrow A component in the ZY plane of FIG. 4 (a) or 6 (a). The results are shown in FIGS. 5A and 5B or FIGS. 7A and 7B. FIG. 5A shows the case of the RFID inlet I1 alone, and FIG. 5B shows the RFID inlet I1. When the slotted metal plate 8 is added, FIG. 7A shows a case where the RFID inlet I2 is used alone, and FIG. 7B shows a case where the slotted metal plate 8 is added to the RFID inlet I2. 5 and 7, Frequency is frequency, Main lobe magnitude is the main beam intensity, Main lobe direction is the main beam direction, and Angular width is the half-value angle. The half-value angle is an angle formed by a point where the intensity (power) becomes half (−3 dB) around the point where the radio wave is the strongest, and indicates the sharpness of directivity. Becomes higher.

  As a result, in the RFID inlet I1, the maximum gain when measured with the RFID inlet I1 alone is −31.3 dBi, and in this state, there is no polarization plane between the antennas, which may cause communication failure or communication failure. There is a risk of becoming a condition. On the other hand, when the slotted metal plate 8 is added, the maximum gain is -3.4 dBi, and by adding the slotted metal plate 8, the gain is improved by about 28 dBi. Thus, by adding the slotted metal plate 8, the polarization plane is adjusted and the communication performance can be improved.

  Similarly, in the RFID inlet I2, the maximum gain in the case of the RFID inlet I1 alone is -30.8 dBi, but when the slotted metal plate 8 is added, it becomes 4.1 dBi, and the gain is improved by about 35 dBi. Even in the case of the RFID inlet I2 having a shape different from that of the RFID inlet I1, it is possible to improve the communication performance by adding the slotted metal plate 8. In this simulation, the same metal plate 8 with slot is used for the RFID inlet I1 and RFID inlet I2. However, the size of the metal plate 8 with slot, the length of S, and the size of S are matched to each inlet. The communication performance can be further improved by adjusting the length.

<One Embodiment of RFID Inspection System of the Present Invention>
Next, an embodiment of the RFID inspection system of the present invention will be described with reference to FIGS. FIG. 8 is an explanatory diagram for explaining an RFID inspection system of the present invention, and FIG. 9 is a flowchart for explaining an inspection process in the RFID inspection system of the present invention.

  The RFID inspection system 10 of the present invention is a system for inspecting communication failure of the RFID tag T in each of the RFID labels L1, L2, L3,. Specifically, as shown in FIG. 8, the RFID inspection system 10 has the base material D1 attached to the RFID labels L1, L2, L3,... Temporarily attached to the base material D1 at a predetermined interval. This is a system for performing a communication inspection such as a communication inspection, whether communication performance is good or communication is impossible by an inspection BOX installed on the back side. In the communication inspection, radio waves are transmitted to the second antennas 9 included in the RFID labels L1, L2, L3,... Conveyed from the first antenna 7a disposed in the inspection BOX, and this transmission is performed. The reflected wave from the second antenna 9 with respect to the received radio wave is received by the first antenna 7a, and the reception sensitivity is inspected.

  In this RFID inspection system 10 as well as the RFID label printer 1, there are various types of RFID labels L1, L2, L3,... Conveyed, and sometimes the polarization plane of the second antenna 9 and the first The polarization plane of the antenna 7a may not match. Even in this case, as in the case of the RFID label printer 1, the orientation of the first antenna 7a may not be changed due to the installation space or the structure.

  Specifically, as shown in FIG. 8A, when the first antenna 7a is set to have a polarization plane in the direction (R / W polarization plane) shown, each RFID label L1 to be conveyed If the polarization planes of the second antennas 9, L2, L3,... Are in the direction shown in the figure (label polarization plane), the polarization planes between the two antennas 7a and 9 match, so that good communication can be performed. On the other hand, as shown in FIG. 8B, the polarization plane of each second antenna 9 of each RFID label L1, L2, L3,. When the direction is orthogonal to the / W polarization plane, the polarization plane of the first antenna 7a and the polarization plane of the second antenna 9 are different, so that it is impossible to perform good communication or communication is impossible depending on the case. In some cases.

  Therefore, in the present invention, the polarization planes of both antennas 7a and 9 can be matched by a simple method even under the situation as shown in FIG. The technique is as shown in FIG. That is, like the RFID label printer 1, the slot S of the slotted metal plate 8 is set so as to match the polarization plane of the first antenna 9, and the slotted metal plate is located in the vicinity of the second antenna 9. 8 is disposed. Since other detailed description is the same as that of the RFID label printer 1, the description thereof is omitted.

  Next, inspection processing in the RFID inspection system 10 configured as described above will be described with reference to FIG. FIG. 9 is a flowchart for explaining inspection processing in the RFID inspection system of the present invention. The inspection process described below is a process executed using a CPU, RAM, and the like by a program stored in advance in a ROM (not shown). Note that the RFID inspection system of the present invention enables good communication by using a slotted metal plate even when the plane of polarization is different between the two antennas as described above. The inspection processing described below is one example, and the present invention is not limited to this, and various other inspection processing methods can be applied.

  First, when the inspection processing program is activated, the first antenna 7a is instructed to transmit radio waves (S100), and a motor (not shown) is activated to convey each RFID label L1, L2,. Processing is started (S101). Thereafter, tip detection processing of the RFID labels L1, L2,... Is performed by a sensor (not shown) (S102). When the sensor detects (Y in S102), a reflected wave reception detection process is performed on the first antenna 7a to determine whether or not a reflected wave is received from the second antenna 9 (S103). Is received (Y in S103), the communication quality of whether the reception sensitivity of the next received reflected wave is good or not is checked (S104). As a result, if it is determined that the reception sensitivity is good (Y in S104), the inspection result is paired with identification information stored in advance on each RFID label L1, L2,. Stored (S106).

  On the other hand, if no reflected wave is received as a result of the reflected wave detection process (N in S103), or if the received wave is received but the reception sensitivity is poor (N in S104), defective product processing is performed. (S105), the result is stored in a storage medium (not shown) together with the identification information of each of the RFID labels L1, L2,.

  Whether the reception sensitivity is good or not is determined as “reception sensitivity good” if the electric field strength of a preset radio wave is a threshold value and the power intensity of the received reflected wave is equal to or greater than this threshold value. On the other hand, if it is lower than the threshold value, it is determined as “bad”. In addition, for the above-described defective product processing, for example, various processing such as removing a defective RFID label or attaching an NG mark can be applied.

  The above process is performed on all RFID labels temporarily attached to the substrate D1, and when it is determined that the above process has been performed on all RFID labels (Y in S107), the RFID label inspection process ends. The embodiment of the present invention is not limited to the above-described embodiment, and various modifications and changes can be made within the same or equivalent range as the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory diagram for explaining the structure of an RFID label printer of the present invention. The block diagram which shows the electrical connection of each part of the RFID label printer of this invention. Explanatory drawing for demonstrating conversion of the polarization plane in this invention. Explanatory drawing for demonstrating one Example of the simulation of the conversion of the polarization plane which applied the metal plate with a slot. (A) is a polar chart showing the gain in the case of the RFID inlet I1 without a slotted metal plate, and (b) is the polar chart showing the gain in the case of the RFID inlet I1 with a slotted metal plate added. Explanatory drawing for demonstrating the other Example of the simulation of the conversion of the polarization plane which applies the metal plate with a slot. (A) is a polar chart showing the gain in the case of the RFID inlet I2 without a slotted metal plate, and (b) is a polar chart showing the gain in the case of the RFID inlet I2 with a slotted metal plate added. Explanatory drawing for demonstrating the RFID test | inspection system of this invention. The flowchart for demonstrating the inspection process in the RFID inspection system of this invention.

Explanation of symbols

1 RFID label printer 2 Reel 3 Platen roller 4 Thermal head (printing means)
5 Ink Ribbon Supply Roller 6 Ink Ribbon Take-up Roller 7 Reader / Writer 7a First Antenna 7b Communication Control Unit 8 Slotted Metal Plate (Slotted Conductive Member)
9 Second antenna 10 RFID inspection system 11 CPU
12 bus 13 ROM
14 RAM
15 Stepping motor (conveying means)
16 Communication I / F
D RFID label original fabric D1 base material I1, I2 RFID inlet L1, L2, L3, ... RFID label R Ink ribbon S Slot T RFID tag

Claims (12)

A wireless communication system for performing wireless communication between a first antenna and a second antenna,
A slotted conductive member is disposed in the vicinity of the second antenna, and the direction of the slot in the slotted conductive member is matched to the plane of polarization of the first antenna. A wireless communication system characterized by acting so as to match the polarization plane of the second antenna.   The wireless communication system according to claim 1, wherein the slotted conductive member is a metal plate.   The wireless communication system according to claim 1, wherein the slotted conductive member is detachably disposed. A first antenna;
A second antenna;
A slotted conductive member disposed in the vicinity of the second antenna,
By adjusting the direction of the slot in the slotted conductive member to the plane of polarization of the first antenna, it acts to match the plane of polarization of the first antenna and the second antenna. Wireless communication system.   The wireless communication system according to claim 4, wherein the slotted conductive member is a metal plate.   The wireless communication system according to claim 4, wherein the slotted conductive member is detachably disposed. Conveying means for conveying a plurality of RFID labels;
Printing means for printing on each RFID label;
A second antenna for each RFID label;
A first antenna in wireless communication with the second antenna;
A slotted conductive member disposed in the vicinity of the second antenna,
By adjusting the direction of the slot in the slotted conductive member to the plane of polarization of the first antenna, it acts to match the plane of polarization of the first antenna and the second antenna. RFID label printer.   The RFID label printer according to claim 7, wherein the slotted conductive member is a metal plate.   The RFID label printer according to claim 7, wherein the slotted conductive member is detachably disposed. Conveying means for conveying a plurality of RFID labels or a plurality of RFID inlets;
An RFID inspection system that includes a first antenna that performs wireless communication with a second antenna of each RFID label or each RFID inlet, and performs a communication inspection of the RFID label or the RFID inlet,
A slotted conductive member is disposed in the vicinity of the second antenna, and the direction of the slot in the slotted conductive member is matched to the plane of polarization of the first antenna. An RFID inspection system characterized by acting so as to match the polarization plane of the second antenna.   The RFID inspection system according to claim 10, wherein the slotted conductive member is a metal plate.   The RFID inspection system according to claim 10, wherein the slotted conductive member is detachably disposed.

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