JP4859020B2 - Wireless tag device - Google Patents

Description

  The present invention relates to a wireless tag device including an antenna unit that transmits and receives data in a contactless manner using electromagnetic waves.

  A wireless tag device including an IC that can store information and an antenna that transmits and receives data without contact by electromagnetic waves can transmit and receive data by radio waves with a wireless device called a reader / writer. Such a wireless tag device is disclosed in Patent Document 1. A wireless tag device that uses a radio wave frequency of 300 MHz or more and does not have an internal power source has a long communicable distance with a reader / writer and is relatively inexpensive. A wireless tag device for barcode replacement is disclosed in Patent Document 2.

  When the wireless tag device does not have a power source, a voltage is obtained by converting radio waves from the reader / writer into direct current using a diode or capacitor inside the IC. When the wireless tag device has a power source, a button-type battery, a film-like battery, and a large-capacity capacitor are used as an IC driving power source.

  The radio wave used for communication between the wireless tag device and the reader / writer can increase the communication distance between the wireless tag and the reader / writer as the transmission power increases, and the propagation loss in the air decreases as the communication frequency decreases. Therefore, the communication distance can be increased. However, the frequency of radio waves that can be used and the output level of radio waves are constrained by the regulatory values set for each country, and the radio wave frequency and radio wave transmission power that provide the maximum effect within the restricted range are selected. A communication system between the RFID tag device and the reader / writer is designed.

  FIG. 3 is a perspective view showing an example of a conventional wireless tag device. The wireless tag device 1 is formed by forming the antenna 3 made of a conductor on the non-conductive substrate 4 and mounting the IC chip 2. The IC chip 2 and the antenna 3 are electrically connected. The antenna 3 is designed so that the input impedance can be matched with the impedance of the IC chip 2 and the frequency used for communication.

  The RFID tag device is used by being affixed to an article for purposes such as inventory management of articles and receipt / shipment history management, and connected to the article with a string. Data such as an identification number and receipt / shipment history information is held in the IC chip of the RFID tag device. In addition, taking advantage of the fact that it is difficult to falsify the identification number, a wireless tag device has been used in recent years for the purpose of authenticating a high-quality product and recycling management using history information.

  However, when a product with a wireless tag device is sold and the product is delivered to the customer, the wireless tag device is tracked by a third party in the state where the wireless tag device is attached. In the case of a wireless tag device having a long distance, there are problems in privacy and security. If the RFID tag device itself is removed from the article in order to avoid this problem, there is a problem in that authentication information and history information cannot be fully utilized.

  In addition to the problem of reading distance, the frequency used for communication is regulated by country or region, causing problems of radio interference with other communication systems, and it is not possible to emit the desired frequency that can communicate with the wireless tag device There was also a problem that there was.

Japanese Patent No. 2555361 JP 2002-298106 A

  The present invention has been made to solve the above-mentioned problems, and its technical problem is to take into account privacy and security, to fully utilize the stored information, and to avoid the influence of radio wave regulation and radio wave interference Is to provide a device.

According to a first aspect of the present invention for achieving the above object, there is provided a wireless tag device comprising: an antenna part having at least an IC chip for storing data; and an antenna for transmitting and receiving the data in a contactless manner by electromagnetic waves. The antenna pattern is formed in a meander shape, and an impedance adjustment object in which a conductor is formed is installed so as to cover the entire antenna at a position where it abuts on the antenna portion, and the radio frequency used for communication is changed. The wireless tag device is characterized.

A second invention for achieving the above object is a wireless tag device in which the impedance adjustment object is installed at a position in contact with the antenna portion via an adhesive member, and a radio frequency used for communication is changed.

  According to the present invention, in a wireless tag device including at least an IC chip that stores data and an antenna unit that transmits and receives data by electromagnetic waves in a non-contact manner, another object is installed at a position in contact with the wireless tag, or the wireless tag By installing another object through the adhesive member at the position where it abuts, using the characteristics of other objects such as dielectric constant, permeability, conductivity, etc., changing the impedance of the antenna, it is possible to communicate The radio frequency to be used can be changed.

  Further, the wireless tag device is used for inventory management in a warehouse or a store, shipping history management in physical distribution, etc. without installing other objects. When another product is installed on the wireless tag device when the product is sold, and the product reaches the customer, the communication frequency changes. In this case, the data of the RFID tag device cannot be read from a distance, but the data can be read at a short distance. Data such as authentication information and shipping history information is not lost, and by removing other objects as necessary, the communication frequency can be changed again so that it can be read over a long distance.

  Furthermore, there was an example of an imported product in which the communication frequency of the wireless tag device used in the producing country cannot be used in the importing country. By the present invention, communication frequency with the wireless tag device can be used in the importing country. .

  As a result, in consideration of privacy and security, it is possible to provide a wireless tag device that makes full use of retained information and avoids the effects of radio wave regulation and radio wave interference.

  A wireless tag device according to the best mode for carrying out the present invention will be described below in detail with reference to the drawings.

  FIG. 1 is a perspective view showing Embodiment 1 of the present invention. FIG. 2 is a perspective view showing Embodiment 2 of the present invention.

  The wireless tag device according to the best mode for carrying out the present invention includes an IC chip 2 and an antenna 3 electrically connected to the IC chip 2. The antenna 3 is designed so that the frequency of the radio wave used for communication and the impedance of the IC chip 2 can be matched. The impedance of the antenna 3 is changed by installing another object (hereinafter referred to as an impedance adjustment object 7) made of a dielectric, a magnetic material, a conductor, or a composite thereof at a position in contact with the wireless tag. As a result, the wireless tag device 1 is designed so that it can be matched with the IC chip 2 in a radio frequency band different from the state before the impedance adjustment object 7 is installed.

  In the best mode of the present invention, the antenna 3 of the RFID tag device 1 is made of a glass epoxy substrate, PET (polyethylene terephthalate), a substrate such as polyimide, or a base material 4 made of paper, such as copper, aluminum, or silver. It is formed by a general antenna forming means such as an etching method or printing using a conductor. The antenna 3 and the IC chip 2 are electrically connected by a general mounting technique such as wire bonding or flip chip mounting.

  In the best mode of the present invention, it is preferable to punch holes 5 in the substrate 4 on which the antenna 3 and the IC chip 2 are mounted, and attach them to an article to be managed through the string 6 or provide an adhesive layer in advance. When the adhesive layer 10 is provided, it is preferably attached or attached to an article to be managed by using a double-sided tape or an adhesive.

  Further, as shown in FIG. 2, an adhesive layer 10 or the like is provided in advance on the impedance adjustment object 7 of the present invention and pasted into an adhesive member, or a screw hole 13 is installed in the article 12 to be managed by the wireless tag device 1. It is also a preferable installation method of the impedance adjusting object 7 to fix the screw 14.

  As shown in FIG. 1, the RFID tag device 1 forms an antenna 3 by printing a conductive paste made of silver as a main component on a base material 4 made of paper, and the IC chip 2 is flip-chip mounted. The antenna 3 is electrically connected. A string 6 is passed through the base material 4 on which the punch holes 5 are formed, and attached to the management object. The antenna impedance is changed by attaching the impedance adjustment object 7 to the wireless tag device 1 from above. The conductor 9 is formed on the base material 8 made of polyethylene terephthalate to produce the impedance adjusting object 7. The impedance adjustment object 7 in the best mode of the present invention may be any object that has any of dielectric constant, magnetic permeability, and electrical conductivity and can affect the impedance.

  The conductor 9 is formed by etching after bonding aluminum on the substrate 8. The conductor 9 and the antenna 3 of the RFID tag device 1 cause radio wave interference, whereby the impedance of the antenna 3 changes and the radio frequency that can be matched with the IC chip 2 also changes, so that the communication frequency can be changed. Here, the pattern of the conductors 9 is designed so that matching can be achieved at a desired communication frequency after pasting.

  In the wireless tag device 1 according to the first embodiment, the frequency used for communication is designed as a 950 MHz band. The antenna is shaped like a meander so that the impedance is easily changed under the influence of the impedance adjustment object 7. In the case of a dipole antenna, the total length of the antenna is required to be about one half of the wavelength of the communication frequency, and is about 16 mm in the case of a communication frequency of 950 MHz. In the first embodiment, the antenna length is shortened by making the antenna pattern meander, and the total length of the antenna portion is about 10 cm.

  When communication was actually performed with the wireless tag device 1 of the first embodiment, the communicable distance was 5 m. Thereby, it turns out that it becomes the radio | wireless tag apparatus 1 suitable for an inventory management use. Further, when the impedance adjustment object 7 is attached to the wireless tag device 1 from above, communication at 2450 MHz becomes possible. At that time, the communicable distance is significantly shortened to 20 cm, and at the same time, communication becomes impossible at the communication frequency of 950 MHz before the pasting. Furthermore, when the pasted impedance adjustment object 7 is removed, communication can be performed at the same 950 MHz as before pasting, and the communication distance is not changed from before pasting.

  As shown in FIG. 2, in the wireless tag device 1 according to the second embodiment of the present invention, the antenna 3 is formed on a base material 4 made of polyimide by etching copper. The IC chip 2 is electrically connected to the antenna 3 by wire bonding. An adhesive layer 10 is formed on the substrate 4, and is adhered to the management target article 12 by the adhesive layer 10. The impedance adjusting object 7 is composed of the base material 8 made of a material in which an epoxy resin and ceramics are mixed and the through holes 11a and 11b. The relative dielectric constant of the material constituting the substrate 8 is 20.

  A screw hole 13 is formed in the management target article 12, and the impedance adjustment object 7 is attached to the management target article 12 to which the wireless tag device 1 is attached by the screw 14 through the through hole 11 b. A through hole 11a is formed so as not to damage the IC chip 2 when the impedance adjustment object 7 is attached. Since the relative permittivity of the base material 8 constituting the impedance adjustment object 7 is high, the impedance of the antenna 3 of the wireless tag device 1 in the second embodiment changes, and the communication frequency can be changed. Although the communication frequency of the wireless tag device 1 in the second embodiment is 400 MHz, the communication frequency becomes 300 MHz when the impedance adjustment object 7 is attached.

  According to the present invention described above, the wireless tag device of the present invention is used for inventory management in a warehouse or store, shipping history management in physical distribution, etc., without installing other objects. When another product is installed in the RFID tag device of the present invention at the time of sale of the product and the product reaches the customer, the communication frequency changes. In this case, the data of the RFID tag device of the present invention cannot be read from a distance, but the data can be read at a short distance.

  In addition, the wireless tag device of the present invention is such that data such as authentication information and shipping history information is not lost, and other objects are removed as necessary, so that the communication frequency can be changed again and reading can be performed over a long distance. Can be set.

  In addition, the communication frequency of the wireless tag device used in the producing country is an example of an imported product that cannot be used in the importing country. However, the wireless tag device of the present invention can be set to a communication frequency that can be used in the importing country. As a result, according to the present invention, it is possible to provide a wireless tag device that takes into consideration privacy and security, fully utilizes the stored information, and avoids the effects of radio wave regulation and radio wave interference.

The perspective view which shows Embodiment 1 of this invention. The perspective view which shows Embodiment 2 of this invention. The perspective view which shows an example of the conventional wireless tag apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 RFID tag apparatus 2 IC chip 3 Antenna 4 Base material 5 Punch hole 6 String 7 Impedance adjustment object 8 Base material 9 Conductor 10 Adhesive layer 11a, 11b Through-hole 12 Management object 13 Screw hole 14 Screw

Claims (2)

In a wireless tag device including an antenna unit in which at least an IC chip for storing data and an antenna for transmitting and receiving the data by electromagnetic waves in a contactless manner are arranged on a base material, the antenna pattern is formed in a meander shape, and the antenna unit A wireless tag device, wherein an impedance adjusting object on which a conductor is formed is installed so as to cover the entire antenna at a position in contact with the antenna, and a radio frequency used for communication is changed. The wireless tag device according to claim 1, wherein the impedance adjusting object is installed via an adhesive member at a position in contact with the antenna unit, and a radio frequency used for communication is changed.

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