JP2018097666A - Reading device and reading method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reading device which recognizes identification information assigned to an ID tag by using a reflected wave from the ID tag, and recognizes identification information without using an ID tag having an arithmetic operation capability or a special function, even when the ID tag is attached to an obstacle.SOLUTION: The reading device including antennae, irradiates an electromagnetic wave to an ID tag 1a attached to a substantially flat surface of an obstacle 4 to detect the level of reception power of a reflected wave from the ID tag 1a with respect to the electromagnetic wave. The reading device irradiates an electromagnetic wave to the ID tag 1a from a region inclined by 10 to 60 degrees to a direction properly facing the ID tag 1a in a predetermined direction by a transmission antenna 11a when recognizing an ID assigned to the ID tag 1a on the basis of the resonance peak of the reception power, and receives a reflected wave with respect to the electromagnetic wave by a reception antenna 11b within a region from a region inclined by 10 degrees to the direction properly facing the ID tag 1a in the opposite direction to the predetermined direction to the region where the electromagnetic wave is irradiated.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a reading apparatus and a reading method for recognizing identification information attached to an ID tag having a conductive antenna, and in particular, the identification information can be recognized even when the ID tag is attached to an obstacle. Regarding technology.

  In recent years, with the progress of the information society, information is recorded on labels and tags attached to products and the like, and products and the like are managed using the labels and tags. In information management using such a label or tag, a non-contact type IC label or non-contact type in which an IC chip capable of writing or reading information in a non-contact state with respect to the label or tag is mounted. Discriminators using RFID technology such as type IC tags are rapidly spreading due to their excellent convenience.

An ID tag using such RFID technology is not limited to an IC chip mounted as described above, but has a plurality of antennas having different resonance peak frequencies, and a plurality of antennas without using an IC chip. A device that can recognize an ID by a combination of antennas is also considered. For example, the shape of the dielectric element and the capacitor element constituting the plurality of antennas may be different, or the shape and direction of the plurality of antennas may be different to change the resonance peak frequency for each of the plurality of antennas. Japanese Patent Application Laid-Open No. H10-228688 discloses a technique that enables IDs to be expressed in combination. If this technology is used, if the number of antennas is N, two information of “1” and “0” can be given depending on the presence / absence of one antenna, and there is no case where all antennas are not present. Thus, (2 ^N −1) IDs can be expressed in a recognizable manner. When such an ID tag is used, a transmitting antenna that radiates electromagnetic waves and a receiving antenna that receives reflected waves from the ID tag with respect to the electromagnetic waves are separated, and the ID tag is irradiated with electromagnetic waves from the transmitting antenna. By receiving the reflected wave from the ID tag with respect to the reception antenna and detecting the resonance peak in the reflected wave, the ID assigned to the ID tag is recognized. Thus, the reception sensitivity can be improved by separating the transmission antenna that radiates electromagnetic waves from the reception antenna that receives the reflected waves from the ID tag with respect to the electromagnetic waves.

  By the way, an ID tag using the RFID technology as described above is often used by being attached to an obstacle such as a product managed using the ID tag. In that case, the electromagnetic wave irradiated to detect the resonance peak of the ID tag is reflected and received not only by the ID tag but also by an obstacle to which the ID tag is attached.

  FIG. 13 is a diagram illustrating frequency characteristics of reflected waves when an electromagnetic wave is irradiated to an ID tag attached to an obstacle.

  When an ID tag provided with an antenna having a resonance peak in the vicinity of 6.8 GHz as shown by the solid line in FIG. 13 is attached to the cardboard box, the reflected wave is generated from the cardboard box as shown by the broken line in FIG. It is buried in the reflection of the ID tag, and the received power of the reflected wave from the ID tag cannot be detected. Further, even when an ID tag provided with an antenna having a frequency characteristic indicated by a solid line in FIG. 13 is attached to a pattern, the reflected wave is buried in the reflection from the pattern as shown by a one-dot chain line in FIG. As a result, the received power of the reflected wave from the ID tag cannot be detected.

  Here, a plurality of receiving antenna elements are provided so as to be able to receive reflected waves having different polarization planes, whereby a wireless tag communication device that realizes highly sensitive communication regardless of the relative positional relationship with the ID tag, It is disclosed in Patent Document 2. However, even if such a technique is used, when the ID tag is attached to an obstacle, the phenomenon that the reflected wave from the ID tag is buried in the reflected wave from the obstacle cannot be solved.

  Therefore, Non-Patent Document 1 discloses a method of removing unnecessary reflected waves other than the ID tag by arithmetic processing. According to the technique disclosed in Non-Patent Document 1, the ID tag is obtained by subtracting the reflected wave in a state where the ID tag is not attached to the obstacle from the reflected wave in a state where the ID tag is attached to the obstacle. Only the level of the received power of the reflected wave from can be detected.

  Also, Non-Patent Document 2 discloses a technique for providing a polarization conversion function to an ID tag. According to the technique disclosed in Non-Patent Document 2, the ID tag is an obstacle by converting the polarization side of the reading device to vertical polarization and the reception side to horizontal polarization and converting the polarization by the ID tag. Even when the obstacle is attached, it is possible to take out only the reflected wave from the ID tag by utilizing the fact that the obstacle does not have a polarization conversion function.

Japanese Patent Publication No. 7-80386 JP 2005-223730 A

F. Costa, S. Genovesi and A. Monorchio, "Normalization-Free Chipless RFIDs by Using Dual-Polarized Interrogation", IEEE Trans. Microw. Theory Tech., Vol. 64, no. 1, 310-318. Jan. 2016 . A. Vena, E. Perret and S. Tedjni. "A Depolarizing Chipless RFID Tag for Robust Detection and Its FCC Compliant UWB Reading System", IEEE Trans. Microw. Theory Tech., Vol. 61, no. 8, 2982-2994 Aug. 2013.

  However, in the technique disclosed in Non-Patent Document 1, the environment other than the ID tag such as an obstacle to which the ID tag is attached needs to be consistent between the case where the ID tag exists and the case where the ID tag does not exist. There is a problem that it is practically difficult to do it outside the system.

  Further, the technique disclosed in Non-Patent Document 2 has a problem that only an ID tag having a polarization conversion function can be used.

  SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems of the related art, and recognizes identification information given to an ID tag using a reflected wave from the ID tag and a reading method. The purpose of the present invention is to provide a reading apparatus and a reading method capable of recognizing identification information without using an ID tag having arithmetic processing or a special function even when the ID tag is attached to an obstacle. .

In order to achieve the above object, the present invention provides:
Identification information provided to the ID tag using a reflected wave from the ID tag with respect to the electromagnetic wave, which is provided with a conductive antenna and irradiates an electromagnetic wave to the ID tag attached to a substantially flat surface of the obstacle. A reader for recognizing and recognizing
A transmitter that generates electromagnetic waves;
A transmission antenna for irradiating the ID tag with the electromagnetic wave generated by the transmission unit;
A receiving antenna that receives a reflected wave of electromagnetic waves emitted from the transmitting antenna;
A receiving unit that detects a level of received power of a reflected wave received by the receiving antenna;
A processing unit that detects a resonance peak of the reflected wave based on the level of received power detected by the receiving unit and recognizes identification information given to the ID tag based on the resonance peak. ,
The transmission antenna is disposed in a region inclined at a predetermined direction from 20 degrees to 60 degrees with respect to a direction facing the ID tag at a timing of reading the identification information,
The receiving antenna is arranged between a region inclined by 10 degrees in a direction opposite to the predetermined direction with respect to a direction facing the ID tag at a timing of reading the identification information to a region where the transmitting antenna is arranged. ing.

In addition, an electromagnetic wave is applied to an ID tag that is provided with a conductive antenna and is mounted on a substantially flat surface of an obstacle, and a level of received power of a reflected wave from the ID tag with respect to the electromagnetic wave is detected. A reading method for recognizing identification information given to the ID tag based on a resonance peak of power,
Irradiating the ID tag with electromagnetic waves from a region inclined by 20 to 60 degrees in a predetermined direction with respect to the direction facing the ID tag;
A reflected wave with respect to the electromagnetic wave is received in a region between a region inclined by 10 degrees in a direction opposite to the predetermined direction with respect to a direction facing the ID tag and a region to which the electromagnetic wave is irradiated.

  In the present invention configured as described above, when an electromagnetic wave is applied to an ID tag attached to a substantially flat surface of an obstacle, the reflected wave from the ID tag has a received power level that is normal to the ID tag. On the other hand, the reflected wave from the obstacle becomes larger in the direction to the reflected wave, and the electromagnetic wave applied to the obstacle reflects the substantially flat surface of the obstacle like a mirror, so that the received power level becomes substantially flat. When the identification information given to the ID tag is recognized using the reflected wave from the ID tag, using the fact that the incident angle and the reflection angle of the electromagnetic wave are larger in the direction where the incident angle and the reflection angle are equal to the facing direction. An electromagnetic wave is applied to the ID tag from a region inclined 20 degrees to 60 degrees in a predetermined direction with respect to the direction facing the ID tag, and 10 degrees in a direction opposite to the predetermined direction with respect to the direction facing the ID tag. Irradiate electromagnetic waves from tilted area By receiving a reflected wave with respect to the electromagnetic wave in the area between the up regions that, so that the reflected waves from the ID tag at the reflected wave is hardly state received from the obstacle with respect to the electromagnetic wave is received. Thereby, even when the ID tag is attached to the obstacle, the identification information can be recognized without using an ID tag having a calculation process or a special function.

  In this case, since the level of the received power of the reflected wave from the ID tag increases in the direction facing the ID tag, the level from the region inclined 10 degrees in the predetermined direction with respect to the region facing the ID tag It is preferable to receive a reflected wave with respect to the electromagnetic wave in a region up to a region inclined by 10 degrees in a direction opposite to the predetermined direction.

  According to the present invention, when the identification information given to the ID tag is recognized using the reflected wave from the ID tag, the region is inclined from 20 to 60 degrees in a predetermined direction with respect to the direction facing the ID tag. An electromagnetic wave is irradiated to the ID tag, and a reflected wave with respect to the electromagnetic wave is generated in a region between a region inclined by 10 degrees in a direction opposite to the predetermined direction with respect to a direction facing the ID tag and a region irradiated with the electromagnetic wave. By receiving, the reflected wave from the ID tag is received in a state in which the reflected wave from the obstacle to the electromagnetic wave is difficult to be received, so that even when the ID tag is attached to the obstacle, the arithmetic processing is performed. The identification information can be recognized without using an ID tag having a special function.

  In this case, since the level of the received power of the reflected wave from the ID tag increases in the direction facing the ID tag, the level from the region inclined 10 degrees in the predetermined direction with respect to the region facing the ID tag It is preferable to receive a reflected wave with respect to the electromagnetic wave in a region up to a region inclined by 10 degrees in a direction opposite to the predetermined direction.

It is a figure which shows the structural example of the ID tag by which ID is recognized by the reader of this invention. It is a block diagram which shows one Embodiment of the reader of this invention. It is a figure for demonstrating the characteristic of the reflected wave of the electromagnetic wave irradiated from the reader | leader shown in FIG. 2, (a) is a figure which shows the characteristic of the reflected wave at the time of irradiating an electromagnetic wave to an obstruction, (b) is It is a figure which shows the characteristic of the reflected wave at the time of irradiating electromagnetic waves to the ID tag shown in FIG. It is a figure which shows the arrangement position of the transmitting antenna and receiving antenna in the reader | leader shown in FIG. FIG. 3 is a diagram illustrating a level of received power of a reflected wave detected by the reader when the arrangement positions of the transmission antenna and the reception antenna in the reader illustrated in FIG. 2 are changed. FIG. 3 is a diagram illustrating a level of received power of a reflected wave detected by the reader when the arrangement positions of the transmission antenna and the reception antenna in the reader illustrated in FIG. 2 are changed. FIG. 3 is a diagram illustrating a level of received power of a reflected wave detected by the reader when the arrangement positions of the transmission antenna and the reception antenna in the reader illustrated in FIG. 2 are changed. FIG. 3 is a diagram illustrating a level of received power of a reflected wave detected by the reader when the arrangement positions of the transmission antenna and the reception antenna in the reader illustrated in FIG. 2 are changed. FIG. 3 is a diagram illustrating a level of received power of a reflected wave detected by the reader when the arrangement positions of the transmission antenna and the reception antenna in the reader illustrated in FIG. 2 are changed. FIG. 3 is a diagram illustrating a level of received power of a reflected wave detected by the reader when the arrangement positions of the transmission antenna and the reception antenna in the reader illustrated in FIG. 2 are changed. FIG. 3 is a diagram illustrating a level of received power of a reflected wave detected by the reader when the arrangement positions of the transmission antenna and the reception antenna in the reader illustrated in FIG. 2 are changed. It is a figure which shows one Embodiment of ID reading system using the reader | leader shown in FIG. 2, (a) is an external appearance perspective view, (b) is a top view. It is a figure which shows the frequency characteristic of the reflected wave at the time of irradiating electromagnetic waves with respect to the ID tag affixed on the obstruction.

  Embodiments of the present invention will be described below with reference to the drawings.

  First, an ID tag whose ID is recognized by the reading device of the present invention will be described.

  FIG. 1 is a diagram showing a configuration example of an ID tag whose ID is recognized by the reading device of the present invention.

  As shown in FIG. 1, the ID tags in this example are ID tags 1a to 1c each having five antenna regions 2a to 2e to which bases 2 made of an insulating material such as resin are assigned different frequencies. is there. In the ID tag 1a, a conductive antenna 3c is formed in only one antenna region 2c among the five antenna regions 2a to 2e. In the ID tag 1b, conductive antennas 3a, 3c, and 3e are formed only in three antenna regions 2a, 2c, and 2e among the five antenna regions 2a to 2e. In the ID tag 1c, conductive antennas 3a to 3e are formed in all of the five antenna regions 2a to 2e.

  The antennas 3a to 3e formed in each of the antenna regions 2a to 2e have a rectangular outer shape, a shape in which a slit enters the longitudinal direction from one of the short sides, and have the same width. However, due to the difference in the length in the longitudinal direction, there is a resonance peak at the frequency assigned to the antenna regions 2a to 2e.

  The ID tags 1a to 1c configured as described above are assigned IDs as identification information, and the antenna regions 2a to 2e are connected to the antennas 3a to 3e according to the IDs assigned to the ID tags 1a to 1c. Is formed. The IDs assigned to the ID tags 1a to 1c are the antennas 3a to 3e formed in the antenna regions 2a to 2e, respectively, in the reflected wave when the ID tags 1a to 1c are irradiated with electromagnetic waves. It will be recognized by whether or not the resonance peak is detected.

  Specifically, a 5-bit ID is assigned to each of the ID tags 1a to 1c, and the value of each of the 5 bits is determined depending on whether or not the antennas 3a to 3e are formed in the five antenna regions 2a to 2e. To do. The first bit of the ID consisting of 5 bits assigned to the ID tags 1a to 1c becomes “1” when the resonance peak due to the antenna 3a formed in the antenna region 2a is detected, and the resonance peak due to the antenna 3a is detected. If not, it will be “0”. Further, the second bit of the ID consisting of 5 bits assigned to the ID tags 1a to 1c becomes “1” when the resonance peak due to the antenna 3b formed in the antenna region 2b is detected, and the resonance peak due to the antenna 3b. If no is detected, it becomes “0”. The third bit of the 5-bit ID assigned to the ID tags 1a to 1c is “1” when the resonance peak due to the antenna 3c formed in the antenna region 2c is detected, and the resonance peak due to the antenna 3c. It is “0” when it is not detected. Further, the fourth bit of the 5-bit ID assigned to the ID tags 1a to 1c becomes “1” when the resonance peak due to the antenna 3d formed in the antenna region 2d is detected, and the resonance peak due to the antenna 3d. If no is detected, it becomes “0”. The fifth bit of the ID consisting of 5 bits assigned to the ID tags 1a to 1c becomes “1” when the resonance peak due to the antenna 3e formed in the antenna region 2e is detected, and the resonance peak due to the antenna 3e. If no is detected, it becomes “0”. By configuring the IDs assigned to the ID tags 1a to 1c in this way, when the electromagnetic waves are irradiated to the ID tags 1a to 1c, using the resonance peak detected by the reflected waves, ID “00100” is determined for the ID tag 1a, ID “10101” is determined for the ID tag 1b, and ID “11111” is determined for the ID tag 1c.

  Next, a reading device that recognizes the IDs of the ID tags 1a to 1c configured as described above will be described.

  FIG. 2 is a block diagram showing an embodiment of the reading apparatus of the present invention.

  As shown in FIG. 2, the reader according to the present embodiment irradiates the ID tag 1a attached to the obstacle 4 such as a delivery item with an electromagnetic wave, and receives the reflected wave to the ID tag 1a. It is a reader 10 that reads and recognizes the assigned ID, and includes a transmission antenna 11 a, a reception antenna 11 b, a transmission unit 12, a reception unit 13, a processing unit 14, and a control unit 15. 2 shows only the ID tag 1a among the ID tags 1a to 1c shown in FIG. 1, but the ID tags 1b and 1c are similarly attached to the obstacle. Thus, the electromagnetic wave is irradiated and the reflected wave is received.

  The obstacle 4 is composed of a cardboard box or the like having a substantially flat surface, and the ID tag 1a is affixed with the substantially flat surface as a pasting surface.

  The transmission unit 12 generates an electromagnetic wave including a frequency assigned to the antenna regions 3a to 3e and irradiates it through the transmission antenna 11a.

  The receiving unit 13 receives a reflected wave from the ID tag 1a with respect to the electromagnetic wave irradiated from the transmitting unit 12 via the transmitting antenna 11a via the receiving antenna 51b, and detects the level of received power of the reflected wave.

  The processing unit 54 detects the resonance peak in the ID tag 1a based on the level of received power detected by the receiving unit 53, and the resonance peak is detected among the frequencies assigned to the antenna regions 3a to 3e. The individual ID for the frequency is set to “1”, the individual ID for the frequency for which no resonance peak is detected is set to “0”, and these “1” and “0” are arranged in the order of the frequencies, whereby the ID tag 1a The ID assigned to is recognized.

  The transmission antenna 11a is arranged in a region inclined in a predetermined direction with respect to the direction facing the ID tag 1a at the timing of irradiating the electromagnetic wave, and irradiates the ID tag 1a with the electromagnetic wave.

  The receiving antenna 11b is arranged in a direction facing the ID tag 1a at the timing of receiving the reflected wave, and receives the reflected wave from the ID tag 1a.

  The control unit 55 controls the irradiation of electromagnetic waves in the transmission unit 52 and each process in the processing unit 54.

  When using the reader 10 configured as described above and recognizing the IDs assigned to the ID tags 1a to 1c, the transmitter 12 generates electromagnetic waves having frequencies assigned to the antenna regions 2a to 2e, While sweeping the frequency band assigned to the antenna regions 2a to 2e, the electromagnetic waves in the frequency band are irradiated to the ID tags 1a to 1c via the transmission antenna 11a.

  Then, the reflected waves from the ID tags 1a to 1c are received by the receiving unit 13 via the receiving antenna 11b, and the level of the received power of the reflected waves is detected, and the processing unit 14 detects the received power level. A resonance peak is detected based on the received power level.

  For the frequencies assigned to the antenna regions 2a to 2e, the individual ID for the frequency where the resonance peak is detected is “1”, and the individual ID for the frequency where the resonance peak is not detected is “0”. The IDs assigned to the ID tags 1a to 1c are recognized by arranging the binary information “1” and “0”, for example, in order of decreasing frequency.

  Here, the characteristics of the reflected wave when the obstacle 4 is irradiated with electromagnetic waves and the reflected wave when the ID tags 1a to 1c are irradiated with electromagnetic waves will be described.

  FIG. 3 is a diagram for explaining the characteristic of the reflected wave of the electromagnetic wave irradiated from the reader 10 shown in FIG. 2, and (a) shows the characteristic of the reflected wave when the obstacle 4 is irradiated with the electromagnetic wave. FIGS. 2B and 2B are diagrams showing the characteristics of reflected waves when the ID tags 1a to 1c shown in FIG. 1 are irradiated with electromagnetic waves.

  With respect to the obstacle 4 as shown in FIG. 2, the reader 10 from a direction inclined by an angle α in a predetermined direction with respect to the direction facing the sticking surface of the ID tag 1 a as shown in FIG. When the electromagnetic wave is irradiated, the irradiated electromagnetic wave is reflected like a mirror on the sticking surface of the obstacle 4, and the level of the received power of the reflected wave is relative to the direction facing the sticking surface of the obstacle 4. It increases in a direction inclined by the same reflection angle α as the incident angle α in a direction opposite to the predetermined direction.

  On the other hand, with respect to the ID tags 1a to 1c shown in FIG. 1, the reader 10 is moved from a direction inclined by an angle α in a predetermined direction with respect to the direction facing the ID tags 1a to 1c as shown in FIG. When the electromagnetic wave is irradiated, the level of the received power of the reflected wave of the irradiated electromagnetic wave increases in the direction facing the ID tags 1a to 1c.

  The arrangement positions of the transmission antenna 11a and the reception antenna 11b were examined using the difference in the reflection directivity of electromagnetic waves between the obstacle 4 and the ID tags 1a to 1c.

  FIG. 4 is a diagram illustrating arrangement positions of the transmission antenna 11a and the reception antenna 11b in the reader 10 illustrated in FIG.

  As shown in FIG. 4, when the electromagnetic wave is irradiated from the transmitting antenna 11a to the ID tag 1a attached to the sticking surface of the obstacle 4 and the reflected wave is received via the receiving antenna 11b, the ID tag 1a The transmitting antenna 11a is arranged at a position inclined by an angle θ1 in the left direction in the figure with respect to the direction directly facing the ID, and at a position inclined by an angle θ2 in the left direction in the figure with respect to the direction facing the ID tag 1a. An experiment was conducted to determine whether or not the resonance peak of the ID tag 1a is detected at the time when the receiving antenna 11b is arranged and these θ1 and θ2 are changed.

  5 to 11 are diagrams illustrating received power levels of reflected waves detected by the reader 10 when the arrangement positions of the transmission antenna 11a and the reception antenna 11b in the reader 10 illustrated in FIG. 2 are changed. .

  First, an experiment was conducted to determine whether the resonance peak of the ID tag 1a is detected by the reader 10 with the angle θ1 for arranging the transmitting antenna 11a being 20 ° and the angle θ2 for arranging the receiving antenna 11b being 0 °.

  Then, as shown in FIG. 5, the resonance peak due to the ID tag 1a can be detected in the level of the received power of the reflected wave received by the receiving antenna 11b in the reflected wave of the obstacle 4. This is because, when the angle θ1 at which the transmitting antenna 11a is disposed is 20 °, the level of the received power of the reflected wave due to the electromagnetic wave irradiated from the transmitting antenna 11a is different from the pasting surface of the obstacle 4 as described above. The reflected wave increases in a direction inclined by 20 °, the same as the incident angle, in the direction opposite to the transmitting antenna 11a with respect to the direction facing the sticking surface of the obstacle 4, while the reflected wave from the ID tag 1a. , The receiving antenna 11b is arranged in the direction facing the ID tag 1a and the receiving antenna 11b because the receiving antenna 11b is arranged in the direction facing the ID tag 1a. This is because the level of the received power becomes smaller in the reflected wave from the sticking surface of the obstacle 4 and becomes larger in the reflected wave from the ID tag 1a. By detecting this resonance peak, the ID assigned to the ID tag 1a can be recognized.

  Next, an experiment was conducted to determine whether the resonance peak of the ID tag 1a is detected by the reader 10 by setting the angle θ1 at which the transmitting antenna 11a is disposed to 10 ° and the angle θ2 at which the receiving antenna 11b is disposed to be 0 °. .

  Then, as shown in FIG. 6, at the level of the received power of the reflected wave received by the receiving antenna 11b, the resonance peak due to the ID tag 1a is buried in the reflected wave of the obstacle 4 and detected. I can't. This is because, when the angle θ1 at which the transmitting antenna 11a is disposed is 10 °, the level of the received power of the reflected wave due to the electromagnetic wave irradiated from the transmitting antenna 11a is as follows in the reflected wave from the ID tag 1a. Is larger in the direction facing the ID tag 1a, while the reflected wave from the sticking surface of the obstacle 4 is opposite to the transmitting antenna 11a in the direction facing the sticking surface of the obstacle 4, Although it increases in the direction inclined by 10 °, the same as the incident angle, at about 10 °, the level of the received power of the reflected wave from the sticking surface of the obstacle 4 does not become so small that the resonance peak by the ID tag 1a can be detected. Because. Therefore, the ID assigned to the ID tag 1a cannot be recognized.

  Next, an experiment was conducted to determine whether the resonance peak of the ID tag 1a is detected by the reader 10 by setting the angle θ1 at which the transmitting antenna 11a is disposed to 30 ° and the angle θ2 at which the receiving antenna 11b is disposed to be 0 °. .

  Then, as shown in FIG. 7, the resonance peak due to the ID tag 1a can be detected in the level of the reception power of the reflected wave received by the receiving antenna 11b in the reflected wave of the obstacle 4. This is because, when the angle θ1 at which the transmitting antenna 11a is disposed is 30 °, the level of the received power of the reflected wave due to the electromagnetic wave irradiated from the transmitting antenna 11a is different from the pasting surface of the obstacle 4 as described above. The reflected wave increases in the direction inclined by 30 °, which is the same as the incident angle, in the direction opposite to the transmitting antenna 11a with respect to the direction facing the sticking surface of the obstacle 4, while the reflected wave from the ID tag 1a. , The receiving antenna 11b is arranged in the direction facing the ID tag 1a and the receiving antenna 11b because the receiving antenna 11b is arranged in the direction facing the ID tag 1a. In the reflected wave from the sticking surface of the obstacle 4, the received power level becomes even smaller than when the angle θ 1 at which the transmission antenna 11 a is disposed is set to 20 °. This is because the increase in reflected waves from 1a. By detecting this resonance peak, the ID assigned to the ID tag 1a can be recognized.

  Next, an experiment was conducted to determine whether the resonance peak of the ID tag 1a is detected by the reader 10 with the angle θ1 at which the transmitting antenna 11a is disposed as 60 ° and the angle θ2 at which the receiving antenna 11b is disposed as 0 °. .

  Then, as shown in FIG. 8, the resonance peak due to the ID tag 1a can be detected in the level of the received power of the reflected wave received by the receiving antenna 11b in the reflected wave of the obstacle 4. This is because when the angle θ1 at which the transmission antenna 11a is disposed is 60 °, the level of the received power of the reflected wave due to the electromagnetic wave irradiated from the transmission antenna 11a is as follows from the sticking surface of the obstacle 4 as described above. The reflected wave becomes larger in the direction inclined by 60 °, the same as the incident angle, in the direction opposite to the transmitting antenna 11a with respect to the direction facing the sticking surface of the obstacle 4, while the reflected wave from the ID tag 1a. , The receiving antenna 11b is arranged in the direction facing the ID tag 1a and the receiving antenna 11b because the receiving antenna 11b is arranged in the direction facing the ID tag 1a. In the reflected wave from the sticking surface of the obstacle 4, the received power level becomes even smaller than when the angle θ 1 at which the transmitting antenna 11 a is disposed is set to 30 °. This is because the increase in reflected waves from 1a. By detecting this resonance peak, the ID assigned to the ID tag 1a can be recognized.

  Next, an experiment was conducted to determine whether the resonance peak of the ID tag 1a is detected by the reader 10 by setting the angle θ1 at which the transmitting antenna 11a is disposed to 30 ° and the angle θ2 at which the receiving antenna 11b is disposed to 10 °. .

  Then, as shown in FIG. 9, the resonance peak due to the ID tag 1a can be detected in the level of the received power of the reflected wave received by the receiving antenna 11b in the reflected wave of the obstacle 4. This is because, when the angle θ1 at which the transmission antenna 11a is disposed is 30 °, the level of the received power of the reflected wave from the electromagnetic wave irradiated from the transmission antenna 11a is about the reflected wave from the pasting surface of the obstacle 4. As described above, the receiving antenna 11b becomes larger in a direction inclined by 30 °, which is the same as the incident angle, in the direction opposite to the transmitting antenna 11a with respect to the direction facing the sticking surface of the obstacle 4. 4 and the level of the received power received by the receiving antenna 11b is such that the obstruction 4 is attached to the surface of the obstacle 4 by being arranged at a position that is inclined only 10 ° with respect to the direction facing the ID tag 1a. This is because the reflected wave from the surface becomes small. On the other hand, in the reflected wave from the ID tag 1a, the level of the received power of the reflected wave due to the electromagnetic wave irradiated from the transmitting antenna 11a increases in the direction facing the ID tag 1a as described above. This is because the level of the received power of the reflected wave from the ID tag 1a does not become so small when the arrangement position of 11b is tilted by 10 ° with respect to the direction facing the ID tag 1a. Furthermore, since the arrangement position of the receiving antenna 11b is tilted toward the transmitting antenna 11a with respect to the direction facing the ID tag 1a, the level of the received power of the reflected wave by the obstacle 4 is reduced, so that the ID tag It becomes easy to detect the resonance peak of 1a. By detecting this resonance peak, the ID assigned to the ID tag 1a can be recognized.

  Next, the angle θ1 at which the transmitting antenna 11a is arranged is 30 °, and the angle θ2 at which the receiving antenna 11b is arranged is −10 °, that is, 10 in the direction opposite to the transmitting antenna 11a with respect to the direction facing the ID tag 1a. An experiment was conducted to determine whether or not the resonance peak of the ID tag 1a is detected by the reader 10 by arranging the receiving antenna 11b at a tilted position.

  Then, as shown in FIG. 10, the resonance peak due to the ID tag 1a can be detected in the level of the received power of the reflected wave received by the receiving antenna 11b in the reflected wave of the obstacle 4. This is because, when the angle θ1 at which the transmission antenna 11a is disposed is 30 °, the level of the received power of the reflected wave from the electromagnetic wave irradiated from the transmission antenna 11a is about the reflected wave from the pasting surface of the obstacle 4. As described above, the receiving antenna 11b becomes larger in a direction inclined by 30 °, which is the same as the incident angle, in the direction opposite to the transmitting antenna 11a with respect to the direction facing the sticking surface of the obstacle 4. 4 and the level of the received power received by the receiving antenna 11b is such that the obstruction 4 is attached to the surface of the obstacle 4 by being arranged at a position that is inclined only 10 ° with respect to the direction facing the ID tag 1a. This is because the reflected wave from the surface becomes small. On the other hand, in the reflected wave from the ID tag 1a, the level of the received power of the reflected wave due to the electromagnetic wave irradiated from the transmitting antenna 11a increases in the direction facing the ID tag 1a as described above. This is because the level of the received power of the reflected wave from the ID tag 1a does not become so small when the arrangement position of 11b is tilted by 10 ° with respect to the direction facing the ID tag 1a. By detecting this resonance peak, the ID assigned to the ID tag 1a can be recognized.

  Next, the angle θ1 at which the transmitting antenna 11a is disposed is 30 °, and the angle θ2 at which the receiving antenna 11b is disposed is −20 °, that is, 20 in the direction opposite to the transmitting antenna 11a with respect to the direction facing the ID tag 1a. An experiment was conducted to determine whether or not the resonance peak of the ID tag 1a is detected by the reader 10 by arranging the receiving antenna 11b at a tilted position.

  Then, as shown in FIG. 11, at the level of the received power of the reflected wave received by the receiving antenna 11b, the resonance peak due to the ID tag 1a is buried in the reflected wave of the obstacle 4 and detected. I can't. This is because, in the reflected wave from the ID tag 1a, the level of the received power of the reflected wave due to the electromagnetic wave irradiated from the transmission antenna 11a is as described above even when the angle θ1 for arranging the transmission antenna 11a is 30 °. In addition, although it increases in the direction facing the ID tag 1a, the arrangement position of the receiving antenna 11b is inclined 20 ° to the opposite side of the transmitting antenna 11a with respect to the direction facing the ID tag 1a. This is because the level of the received power of the reflected wave from 1a becomes small. As for the reflected wave from the sticking surface of the obstacle 4, the level of the received power of the reflected wave due to the electromagnetic wave irradiated from the transmitting antenna 11 a is in the direction facing the sticking surface of the obstacle 4 as described above. In the direction opposite to the transmitting antenna 11a and in the direction inclined by 30 °, which is the same as the incident angle, the receiving antenna 11b is a transmitting antenna with respect to the direction facing the sticking surface of the obstacle 4 and the ID tag 1a. Although tilted by 20 ° in the opposite direction to 11a, at about 10 °, the level of the received power of the reflected wave from the obstacle 4 is the resonance peak due to the reflected wave from the ID tag 1a with the received power level being reduced. This is because it is not so small that it can be detected. Therefore, the ID assigned to the ID tag 1a cannot be recognized.

  In view of the above experimental results, in the transmission antenna 11a, from a position inclined 20 ° in one direction to a position inclined 60 ° in the same direction with respect to the direction facing the sticking surface of the obstacle 4 and the ID tag 1a. It can be seen that the ID assigned to the ID tag 1a can be recognized when the ID tag 1a is placed. The receiving antenna 11b is given to the ID tag 1a when the receiving antenna 11b is arranged at a position inclined by 10 ° in the opposite direction to the transmitting antenna 11a with respect to the direction facing the sticking surface of the obstacle 4 and the ID tag 1a. If the received ID can be recognized and is disposed on the transmitting antenna 11a side from that position, the level of the received power of the reflected wave from the obstacle 4 is decreasing, so the ID assigned to the ID tag 1a is recognized. it can.

  That is, when recognizing the ID assigned to the ID tag 1a using the reflected wave from the ID tag 1a, the ID is identified from a region inclined 20 degrees to 60 degrees in one direction with respect to the direction facing the ID tag 1a. Irradiate the electromagnetic wave to the tag, and reflect the reflected wave to the electromagnetic wave in a region between the region inclined 10 degrees in the direction opposite to the transmitting antenna 11a with respect to the direction facing the ID tag 1a to the region irradiated with the electromagnetic wave. By receiving, the reflected wave from the ID tag 1a is received in a state in which the reflected wave from the obstacle 4 with respect to the electromagnetic wave is difficult to be received, and thereby the ID tag 1a is attached to the obstacle 4 However, the ID can be recognized without using an ID tag having arithmetic processing or a special function. At that time, the receiving antenna 11b is preferably arranged in a direction facing the sticking surface of the obstacle 4 and the ID tag 1a rather than the transmitting antenna 11a, and the transmitting antenna 11a with respect to a region facing the ID tag 1a. It is preferable to be disposed in a region between a region tilted 10 degrees in the direction in which it is disposed and a region tilted 10 degrees in the opposite direction.

  If the receiving antenna 11b is arranged between the area facing the obstruction 4 and the ID tag 1a and the area inclined 10 degrees in the opposite direction to the transmitting antenna 11a, the ID tag 1a When detecting the level of the received power of the reflected wave, it is possible to make it difficult for the ID tag 1a to receive interference due to the electromagnetic wave irradiated.

  Hereinafter, an ID reading system using the above-described reader 10 will be described.

  FIGS. 12A and 12B are diagrams showing an embodiment of an ID reading system using the reader 10 shown in FIG. 2, wherein FIG. 12A is an overall perspective view, and FIG. 12B is a top view.

  As shown in FIG. 12, in the reading system according to this embodiment, the reader 10 shown in FIG. 2 is configured as a tunnel-type reader for line work. The tunnel type reader 10 is arranged so as to straddle the conveyor 20 on which the obstacles 4a to 4d to which the ID tags 1a to 1d are affixed are conveyed, and a transmitting antenna 11a and a receiving antenna 11b are provided on one inner wall surface thereof. Is attached.

  The obstacles 4a to 4d are arranged on the conveyor 20 so that the affixed ID tags 1a to 1d face the inner wall surface to which the transmission antenna 11a and the reception antenna 11b are attached when the obstacles 4a to 4d pass through the reader 10. It is placed on and transported.

  As shown in FIG. 12B, the transmission antenna 11a and the reception antenna 11b are attached to a region facing an obstacle to which an ID tag to be read of ID is attached. And the angle with respect to the sticking surface of ID tag 1a-1d of the obstructions 4a-4d conveyed on the conveyor 20, and ID tag 1a-1d of each of the transmission antenna 11a and the reception antenna 11b, and transmission is as above-mentioned. In the antenna 11a, the antenna 11a is disposed in a region inclined 20 degrees to 60 degrees on the upstream side in the transport direction of the obstacle 4 with respect to the direction facing the ID tags 1a to 1d to be read, and in the receiving antenna 11b, It is arranged between a region inclined 10 degrees downstream of the obstacle 4 in the conveyance direction with respect to the direction facing the ID tags 1a to 1d as ID reading targets to a region where the transmission antenna 11a is arranged.

  In the reading system configured as described above, the ID tags attached to the obstacles 4a to 4d at the timing when the obstacles 4a to 4d conveyed on the conveyor 20 face the transmission antenna 11a and the reception antenna 11b. Since the ID is read and recognized by the reader 10 from 1a to 1d, the transmission antenna 11a is directed to the direction facing the ID tags 1a to 1d at the timing of reading the ID from the ID tags 1a to 1d. The receiving antenna 11b is arranged in an area inclined 20 degrees to 60 degrees upstream of the obstacle 4 in the conveyance direction, and is directed to the direction facing the ID tags 1a to 1d at the timing of reading the ID from the ID tags 1a to 1d. Between the area inclined 10 degrees downstream of the obstacle 4 in the conveyance direction and the area where the transmission antenna 11a is arranged It will have been location.

  According to the reading system configured in this way, as described above, the ID assigned to the ID tags 1a to 1d attached to the obstacles 4a to 4d conveyed on the conveyor 20 is accurately determined by the reader 10. Can be recognized.

  In the reading system according to the present embodiment, the transmission antenna 11a is inclined by 20 degrees to 60 degrees on the upstream side in the conveyance direction of the obstacle 4 with respect to the direction facing the ID tags 1a to 1d that are ID reading targets. An area where the transmission antenna 11a is arranged from an area where the reception antenna 11b is inclined 10 degrees downstream in the conveyance direction of the obstacle 4 with respect to the direction facing the ID tags 1a to 1d which are ID reading targets. Although the transmission antenna 11a is disposed between the ID tag 1a to 1d as the ID reading target, the transmission antenna 11a is inclined 20 degrees to 60 degrees on the downstream side in the conveyance direction of the obstacle 4 The transmission antenna 11 from a region where the reception antenna 11b is inclined 10 degrees upstream of the direction in which the obstacle 4 is conveyed with respect to the direction facing the ID tags 1a to 1d that are ID reading targets. There may be disposed between the up placement area. Further, the transmission antenna 11a is arranged in a region inclined 20 degrees to 60 degrees upward with respect to the direction facing the ID tags 1a to 1d that are ID reading targets. In the receiving antenna 11b, the ID reading target is It may be arranged between the area inclined 10 degrees downward from the direction facing the ID tags 1a to 1d to the area where the transmission antenna 11a is arranged, and conversely, the transmission antenna 11a is The receiving antenna 11b is arranged in a region tilted downward by 20 to 60 degrees with respect to the direction facing the ID tags 1a to 1d to be read IDs, and the receiving antenna 11b is directly connected to the ID tags 1a to 1d to be read IDs. You may arrange | position between the area | region where the transmission antenna 11a is arrange | positioned from the area | region inclined 10 degree | times upwards with respect to the direction.

  Further, as shown in FIG. 1, the ID tag whose ID is read by the reader of the present invention is not limited to one having a plurality of antenna areas to which different frequencies are assigned, and has one antenna area. Then, an antenna having a resonance peak corresponding to the ID assigned to the ID tag may be formed in this antenna region.

1a to 1d ID tag 2 base substrate 2a to 2e antenna area 3a to 3e antenna 4, 4a to 4d obstacle 10 reader 11a transmission antenna 11b reception antenna 12 transmission unit 13 reception unit 14 processing unit 15 control unit 20 conveyor

Claims (4)

Identification information provided to the ID tag using a reflected wave from the ID tag with respect to the electromagnetic wave, which is provided with a conductive antenna and irradiates an electromagnetic wave to the ID tag attached to a substantially flat surface of the obstacle. A reader for recognizing and recognizing
A transmitter that generates electromagnetic waves;
A transmission antenna for irradiating the ID tag with the electromagnetic wave generated by the transmission unit;
A receiving antenna that receives a reflected wave of electromagnetic waves emitted from the transmitting antenna;
A receiving unit that detects a level of received power of a reflected wave received by the receiving antenna;
A processing unit that detects a resonance peak of the reflected wave based on the level of received power detected by the receiving unit and recognizes identification information given to the ID tag based on the resonance peak. ,
The transmission antenna is disposed in a region inclined at a predetermined direction from 20 degrees to 60 degrees with respect to a direction facing the ID tag at a timing of reading the identification information,
The receiving antenna is arranged between a region inclined by 10 degrees in a direction opposite to the predetermined direction with respect to a direction facing the ID tag at a timing of reading the identification information to a region where the transmitting antenna is arranged. The reading device. The reading device according to claim 1.
The receiving antenna has a timing at which the identification information is read, between a region inclined by 10 degrees in the predetermined direction with respect to a region facing the ID tag and a region inclined by 10 degrees in a direction opposite to the predetermined direction. Arranged reading device. An electromagnetic wave is applied to an ID tag that is provided with a conductive antenna and is mounted on a substantially flat surface of an obstacle, and the level of received power of a reflected wave from the ID tag with respect to the electromagnetic wave is detected. A reading method for recognizing identification information given to the ID tag based on a resonance peak,
Irradiating the ID tag with electromagnetic waves from a region inclined by 20 to 60 degrees in a predetermined direction with respect to the direction facing the ID tag;
A reading method in which a reflected wave with respect to the electromagnetic wave is received in a region between a region inclined by 10 degrees in a direction opposite to the predetermined direction with respect to a direction directly facing the ID tag and a region irradiated with the electromagnetic wave. The reading method according to claim 3.
Read a reflected wave with respect to the electromagnetic wave in a region between a region inclined 10 degrees in the predetermined direction and a region inclined 10 degrees in the opposite direction to the predetermined direction with respect to the region facing the ID tag. Method.

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