JP2010102445A - Radio communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radio communication system that uses a radio IC device implementing a small, simple structure, low manufacturing costs, a low power consumption and a high information transmission rate. <P>SOLUTION: The radio communication system includes: the radio IC device including an electromagnetic coupling module 1 comprising a radio IC chip 5 and a feeder circuit board 10, and a radiator 20 adapted to couple with the electromagnetic coupling module 1 when in proximity thereto; and a reader/writer. For example, the electromagnetic coupling module 1 is fixed on a door and the radiator 20 is fixed on a frame member of the door. When the door is closed, the electromagnetic coupling module 1 and the radiator 20 are proximate and coupled to enable communication with the reader/writer. When the door is opened, both are decoupled to disable communication with the reader/writer. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a wireless communication system, and more particularly to a wireless communication system using an RFID (Radio Frequency Identification) system using a wireless IC device and a reader / writer.

  Conventionally, as an article management system, a reader / writer that generates an induction electromagnetic field and an IC chip (also referred to as an IC tag or a wireless IC chip) that stores predetermined information attached to an article or a container are communicated in a non-contact manner. RFID systems that transmit information have been developed. The IC chip can be communicated with a reader / writer by being coupled with an antenna, that is, a radiation plate.

  On the other hand, it is also considered to use a RFID system to construct a security system that detects opening and closing of doors, windows, and the like, and it is conceivable to use the sensor switch described in Patent Document 1 as this type of sensor. This sensor switch includes an antenna coil connected to an opening / closing element and an IC module that operates with electric power from the antenna coil and wirelessly communicates with the outside.

However, this sensor switch requires an opening / closing element separately from the IC module and is expensive, and requires electric power to operate the opening / closing element. Therefore, the antenna coil is enlarged. In order to read information from the IC module after being written in the module, there is a problem that transmission of the opening / closing information is slow.
Japanese Patent Laying-Open No. 2005-086415

  SUMMARY OF THE INVENTION An object of the present invention is to provide a wireless communication system using a wireless IC device which is small in size and can be manufactured at low cost, is a power saving type, and has a high information transmission speed.

The wireless communication system according to the first aspect of the present invention is:
An electromagnetic coupling module comprising: a wireless IC that processes a predetermined wireless signal; and a feeder circuit board having a feeder circuit coupled to the wireless IC;
By being close to the electromagnetic coupling module, the power supply circuit is coupled to the power supply circuit by an electric field, a magnetic field, or an electromagnetic field, and a transmission signal supplied from the power supply circuit is radiated, and a reception signal is received and supplied to the power supply circuit. A radiation plate,
A wireless IC device comprising:
A reader / writer that exchanges signals with the wireless IC device;
A wireless communication system comprising:
The electromagnetic coupling module is fixed to the first object, the radiation plate is fixed to the second object, and the proximity / separation between the electromagnetic coupling module and the radiation plate is caused by the proximity / separation of the first object and the second object. Detecting by the reader / writer,
It is characterized by.

  The wireless communication system according to the first embodiment includes two independent members, an electromagnetic coupling module and a radiation plate, which are electromagnetically coupled by being close to each other. A power / information transmission path called IC is formed. The radiation plate receives a signal from the reader / writer, and this received signal is supplied to the wireless IC through a power feeding circuit. The wireless IC emits a response signal, and this response signal is transmitted to the radiation plate via the power feeding circuit and radiated to the reader / writer. Such communication is possible when the first object and the second object are close to each other, for example, when a door or window is closed, and if the door or window is opened, communication is impossible. Become. Thus, the security of the room can be managed.

The wireless communication system according to the second aspect of the present invention is
An electromagnetic coupling module comprising: a wireless IC that processes a predetermined wireless signal; and a feeder circuit board having a feeder circuit coupled to the wireless IC;
By being close to the electromagnetic coupling module, the power supply circuit is coupled to the power supply circuit by an electric field, a magnetic field, or an electromagnetic field, and a transmission signal supplied from the power supply circuit is radiated, and a reception signal is received and supplied to the power supply circuit. A first radiation plate and a second radiation plate;
A wireless IC device comprising:
A reader / writer that exchanges signals with the wireless IC device;
A wireless communication system comprising:
The first radiation plate is fixed to a first object, the second radiation plate is fixed to a second object, the electromagnetic coupling module is fixed to a third object, and the first object and the second object of the second object are fixed. Detecting the proximity / separation between the first radiation plate and the second radiation plate and the electromagnetic coupling module accompanying the proximity / separation with respect to the three objects by the reader / writer;
It is characterized by.

  In the wireless communication system according to the second embodiment, the wireless IC device can communicate with the reader / writer by bringing the first radiation plate and the second radiation plate close to the electromagnetic coupling module. For example, the first object and the second object to which the first radiation plate and the second radiation plate are fixed are windows, fences, shojis, or doors that are closed with overlapping portions, and the electromagnetic coupling module is fixed. The third object is a window, a fence, a shoji, or a window frame member, and can manage the security of the room.

  According to the present invention, it is possible to construct a security system using the fact that the wireless IC device establishes / not establishes communication with the reader / writer due to the proximity / separation of the electromagnetic coupling module and the radiation plate. Moreover, the wireless IC device has a simple configuration of an electromagnetic coupling module and a radiation plate, can be manufactured at low cost, and can save power by using a signal from a reader / writer as power. In addition, since the signal is exchanged directly with the wireless IC, the information transmission speed is extremely rapid.

  Embodiments of a wireless communication system according to the present invention will be described below with reference to the accompanying drawings. In addition, in each figure, the same code | symbol is attached | subjected to a common component and part, and the overlapping description is abbreviate | omitted.

(Wireless IC device, see FIGS. 1 to 3)
First, a wireless IC device used in the wireless communication system according to the present invention will be described. FIG. 1 shows a wireless IC device. The wireless IC device includes an electromagnetic coupling module 1 including a wireless IC chip 5 that processes a transmission / reception signal having a predetermined frequency and a power supply circuit board 10 on which the wireless IC chip 5 is mounted, and a base material 21 such as a PET film. It is comprised with the radiation plate 20 formed in this.

  The radiation plate 20 is bent in a meander shape, and the electromagnetic coupling module 1 is disposed close to the center of the radiation plate 20 so as to be electromagnetically coupled to the power feeding circuit 11 built in the power feeding circuit board 10. The radiation plate 20 is formed by attaching a metal thin plate made of a conductive material such as aluminum foil or copper foil on the base material 21 and patterning it, or conductive paste such as Al, Cu or Ag on the base material 21. Or by patterning a film provided by plating.

  As shown in FIG. 2 as an equivalent circuit, the feeder circuit board 10 includes resonance elements L1 and L2 having inductance values different from each other and magnetically coupled in opposite phases to each other (indicated by a mutual inductance M). A power supply circuit 11 having a circuit / matching circuit (details will be described below with reference to FIG. 3) is provided.

  The wireless IC chip 5 includes a clock circuit, a logic circuit, a memory circuit, and the like. Necessary information is stored, and a pair of input / output terminal electrodes and a pair of mounting terminal electrodes (not shown) are provided on the back surface. The input / output terminal electrodes are electrically connected to the power supply terminal electrodes 42a and 42b formed on the power supply circuit board 10, and the mounting terminal electrodes are electrically connected to the mounting electrodes 43a and 43b via metal bumps or the like.

  The inductance elements L1 and L2 included in the power feeding circuit 11 are magnetically coupled in opposite phases, resonate at a frequency processed by the wireless IC chip 5, and are electromagnetically coupled to the radiation plate 20. The power feeding circuit 11 matches the impedance of the wireless IC chip 5 (usually 50Ω) and the impedance of the radiation plate 20 (space impedance 377Ω).

  Accordingly, the power feeding circuit 11 transmits a transmission signal having a predetermined frequency transmitted from the wireless IC chip 5 to the radiation plate 20 and selects a reception signal having a predetermined frequency from the signal received by the radiation plate 20. To the wireless IC chip 5. Therefore, in this wireless IC device, the wireless IC chip 5 is operated by a signal received by the radiation plate 20, and a response signal from the wireless IC chip 5 is emitted from the radiation plate 20 to the outside.

  As described above, in the wireless IC device, since the resonance frequency of the signal is set by the power feeding circuit 11 provided on the power feeding circuit board 10, the radio IC device operates as it is even when the radiation plate 20 is attached to various articles. Variations in characteristics are suppressed, and there is no need to change the design of the radiation plate 20 or the like for each individual article. The frequency of the transmission signal radiated from the radiation plate 20 and the frequency of the reception signal supplied to the wireless IC chip 5 substantially correspond to the resonance frequency of the power feeding circuit 11 in the power feeding circuit board 10. Since the frequency of the transmission / reception signal is determined in the power supply circuit board 10, the frequency characteristics change regardless of the shape, size, arrangement, etc. of the radiation plate 20 even if the radiation plate 20 is rounded or sandwiched between dielectrics, for example. Stable frequency characteristics can be obtained without doing so.

  Here, the configuration of the feeder circuit board 10 will be described with reference to FIG. The feeder circuit board 10 is obtained by laminating, pressing and firing ceramic sheets 41a to 41h made of a dielectric or magnetic material. On the uppermost sheet 41a, power supply terminal electrodes 42a and 42b, mounting electrodes 43a and 43b, and via-hole conductors 44a, 44b, 45a, and 45b are formed. In the second to eighth sheets 41b to 41h, wiring electrodes 46a and 46b constituting inductance elements L1 and L2 are formed, and via hole conductors 47a, 47b, 48a and 48b are formed as necessary. ing.

  By laminating the above sheets 41a to 41h, the inductance element L1 in which the wiring electrode 46a is spirally connected by the via-hole conductor 47a is formed, and the inductance in which the wiring electrode 46b is spirally connected by the via-hole conductor 47b. Element L2 is formed. Further, a capacitance is formed between the wiring electrodes 46a and 46b.

  The end 46a-1 of the wiring electrode 46a on the sheet 41b is connected to the power supply terminal electrode 42a via the via hole conductor 45a, and the end 46a-2 of the wiring electrode 46a on the sheet 41h is connected via the via hole conductors 48a and 45b. Connected to the power supply terminal electrode 42b. The end 46b-1 of the wiring electrode 46b on the sheet 41b is connected to the power supply terminal electrode 42b via the via hole conductor 44b, and the end 46b-2 of the wiring electrode 46b on the sheet 41h is connected via the via hole conductors 48b and 44a. Connected to the power supply terminal electrode 42a.

  In the above power feeding circuit 11, since the inductance elements L1 and L2 are wound in opposite directions, the magnetic fields generated by the inductance elements L1 and L2 are canceled out. Since the magnetic field cancels out, it is necessary to lengthen the wiring electrodes 46a and 46b to some extent in order to obtain a desired inductance value. As a result, the Q value is lowered, so that the steepness of the resonance characteristics is lost, and the bandwidth is increased in the vicinity of the resonance frequency.

(Wireless communication system, see FIGS. 4 to 10)
A wireless communication system according to an embodiment communicates information with a reader / writer using the wireless IC device. That is, the electromagnetic coupling module 1 and the radiation plate 20 constituting the wireless IC device are separated, fixed to different first and second objects, and electromagnetic coupling accompanying the proximity / separation of the first object and the second object. The proximity / separation between the module 1 and the radiation plate 20 is detected by a reader / writer.

  Specifically, as shown in FIG. 4, a reader / writer 52 that interlocks with the computer 51 is provided in the room 50, and wireless IC devices are attached to the doors 61 and 62, the window 71, the safe 81, and the figurine 85. The reader / writer 52 includes an antenna 53 for transmission / reception.

  As shown in FIG. 5, the electromagnetic coupling module 1 is fixed to a door 61 that is opened and closed with a hinge 64 as a fulcrum, and the radiation plate 20 is fixed to a frame member 63. As shown in FIG. 5A, when the door 61 is closed, the electromagnetic coupling module 1 and the radiation plate 20 are close to each other, and can communicate with the reader / writer 52 by electromagnetic coupling. On the other hand, as shown in FIG. 5B, when the door 61 is opened, the electromagnetic coupling module 1 and the radiation plate 20 are separated from each other, and communication with the reader / writer 52 becomes impossible.

  Therefore, if the wireless IC device responds to the signal from the reader / writer 52, the computer 51 determines that the door 61 is closed. On the other hand, if the wireless IC device does not respond, the computer 51 determines that the door 61 has been opened. Thus, the security of the room 50 can be managed. The same applies to the door 62.

  FIG. 6 shows another embodiment, in which the radiation plate 20 is fixed to the door 61 and the electromagnetic coupling module 1 is fixed to the frame member 63. In addition, the electromagnetic coupling module 1 and the radiation plate 20 may be attached to arbitrary locations that are close to / separated by opening / closing the door 61 other than the locations shown in FIGS. 5 and 6. Further, by changing the electrode shape of the coupling portion of the feeder circuit board 10 with the radiation plate 20 and the configuration of the feeder circuit, the coupling between the feeder circuit and the radiation plate 20 can be changed to only an electric field or only a magnetic field.

  FIG. 7 shows a state where the wireless IC device is attached to the window 71. The window 71 has window glasses 72 and 73 that can be opened and closed in an overlapping manner, the electromagnetic coupling module 1 is fixed to the sash 72a, and the radiation plate 20 is fixed to the sash 73a. When the window glasses 72 and 73 are closed, the electromagnetic coupling module 1 and the radiation plate 20 are close to each other, and can communicate with the reader / writer 52 by electromagnetic coupling. On the other hand, when the window glasses 72 and 73 are opened, the electromagnetic coupling module 1 and the radiation plate 20 are separated from each other, and communication with the reader / writer 52 becomes impossible.

  FIG. 8 shows a form in which the electromagnetic coupling module 1 is fixed to the lever 76 of the lock mechanism 75 of the window glasses 72 and 73 and the radiation plate 20 is fixed to the sash 72a. The lever 76 can be moved to the lock position X1 and the release position X2. When the lever 76 is at the lock position X1, the electromagnetic coupling module 1 and the radiation plate 20 are close to each other, and can communicate with the reader / writer 52 by electromagnetic coupling. . On the other hand, when the lever 76 moves to the release position X2, the electromagnetic coupling module 1 and the radiation plate 20 are separated from each other, and communication with the reader / writer 52 becomes impossible.

  In addition, regarding the window 71, you may fix the electromagnetic coupling module 1 and the radiation plate 20 to a glass sash and a window frame, respectively.

  With respect to the safe 81, the electromagnetic coupling module 1 and the radiation plate 20 are normally attached to the safe 81 and its table 82 in an electromagnetically coupled state. When the safe 81 is moved, this coupled state is released, and the wireless IC The device stops working. The figurine 85 is the same.

  As shown in FIG. 9, if the reed ridges 91 and 92 are the same (the same applies to a shoji screen or the like), the radiation plates 20 a and 20 b divided in half are fixed to the upper sides of the ridges 91 and 92, The electromagnetic coupling module 1 may be fixed to a duck that does not. When the flanges 91 and 92 are closed, the radiation plates 20a and 20b are close to each other, and the electromagnetic coupling module 1 is electromagnetically coupled close to the ends of the radiation plates 20a and 20b. When the eaves 91 and 92 are opened, this coupled state is released and the wireless IC device does not operate.

  As shown in FIG. 10, in the case of double doors 95 and 96, the radiation plates 20a and 20b divided in half are fixed to the upper limit portions of the doors 95 and 96, and the electromagnetic coupling module 1 is attached to a frame member (not shown). It may be fixed. When the doors 95 and 96 are closed, the radiation plates 20a and 20b are close to each other, and the electromagnetic coupling module 1 is electromagnetically coupled close to the ends of the radiation plates 20a and 20b. When the doors 95 and 96 are opened, this coupled state is released and the wireless IC device does not operate. A wireless IC device used in the embodiment shown in FIGS. 9 and 10 is shown in FIG. By electrically disposing the capacitive electrodes 12a and 12b in the feeder circuit board 10 at the ends of the two radiation plates 20a and 20b so as to face each other, both can be electric field coupled. The power feeding circuit 11 includes three inductance elements.

(Other examples)
In addition, the radio | wireless communications system which concerns on this invention is not limited to the said Example, It can change variously within the range of the summary.

  For example, the electromagnetic coupling module 1 and the radiation plate 20 can be fixed to various types other than those shown in the above embodiment, and the coupling / release can be detected by a reader / writer. Also, regarding the wireless IC device, the power supply circuit board and the like are merely examples, and the power supply circuit can employ various configurations. The wireless IC may be manufactured as an element in the power supply circuit board. By forming the wireless IC part in the power supply circuit board, the parasitic component in the connection part between the wireless IC part and the power supply circuit can be eliminated, and the characteristics of the wireless IC device can be improved. Also, the height of the electromagnetic coupling module can be reduced. Furthermore, an impedance matching circuit can be added to the power feeding circuit as a form of the electromagnetic coupling module. Further, the frequency of the transmission / reception signal may be determined by the radiation plate, or may be determined by the feeding circuit and the radiation plate.

Explanatory drawing which shows an example of the radio | wireless IC device used by this invention. FIG. 3 is an equivalent circuit diagram showing a power feeding circuit provided on a power feeding circuit board constituting the wireless IC device. The top view which shows the laminated structure of the said electric power feeding circuit board. BRIEF DESCRIPTION OF THE DRAWINGS Explanatory drawing which shows the radio | wireless communications system which is one Example of this invention. 1A and 1B show a form in which a wireless IC device is attached to a single door, in which FIG. 4A is a plan view in a closed state, and FIG. The top view which shows the other form which attached the wireless IC device to the single door. The front view which shows one form which attached the wireless IC device to the sliding window. The other form which attached the wireless IC device to the sliding window is shown, (A) is a side view, (B) is a front view. The perspective view which shows one form which attached the wireless IC device to the sliding hook. The top view which shows the form which attached the wireless IC device to the double doors. The schematic block diagram of the radio | wireless IC device shown in FIG.9 and FIG.10.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Electromagnetic coupling module 5 ... Wireless IC chip 10 ... Power feeding circuit board 11 ... Power feeding circuit 52 ... Reader / writer

Claims (8)

An electromagnetic coupling module comprising: a wireless IC that processes a predetermined wireless signal; and a feeder circuit board having a feeder circuit coupled to the wireless IC;
By being close to the electromagnetic coupling module, the power supply circuit is coupled to the power supply circuit by an electric field, a magnetic field, or an electromagnetic field, and a transmission signal supplied from the power supply circuit is radiated, and a reception signal is received and supplied to the power supply circuit. A radiation plate,
A wireless IC device comprising:
A reader / writer that exchanges signals with the wireless IC device;
A wireless communication system comprising:
The electromagnetic coupling module is fixed to the first object, the radiation plate is fixed to the second object, and the proximity / separation between the electromagnetic coupling module and the radiation plate is caused by the proximity / separation of the first object and the second object. Detecting by the reader / writer,
A wireless communication system.   The wireless communication system according to claim 1, wherein the first object is a door frame or a door, and the second object is a door or a door frame.   2. The wireless communication system according to claim 1, wherein the first object and the second object are a window, a fence, a shoji, or a door that has an overlapping portion and is closed.   2. The wireless communication system according to claim 1, wherein the first object is a lever that can move between a lock position and a release position, and the second object is a sash that contacts and separates the lever. An electromagnetic coupling module comprising: a wireless IC that processes a predetermined wireless signal; and a feeder circuit board having a feeder circuit coupled to the wireless IC;
By being close to the electromagnetic coupling module, the power supply circuit is coupled to the power supply circuit by an electric field, a magnetic field, or an electromagnetic field, and a transmission signal supplied from the power supply circuit is radiated, and a reception signal is received and supplied to the power supply circuit. A first radiation plate and a second radiation plate;
A wireless IC device comprising:
A reader / writer that exchanges signals with the wireless IC device;
A wireless communication system comprising:
The first radiation plate is fixed to a first object, the second radiation plate is fixed to a second object, the electromagnetic coupling module is fixed to a third object, and the first object and the second object of the second object are fixed. Detecting the proximity / separation between the first radiation plate and the second radiation plate and the electromagnetic coupling module accompanying the proximity / separation with respect to the three objects by the reader / writer;
A wireless communication system.   The first object and the second object are windows, fences, shojis, or doors that are closed with overlapping portions, and the third object is a frame member of the window, fence, shojis, or doors. The wireless communication system according to claim 5, characterized in that:   The radio communication system according to any one of claims 1 to 6, wherein a frequency of a signal transmitted / received by the radiation plate is substantially determined by a resonance frequency of the power feeding circuit.   8. The wireless communication system according to claim 1, wherein the power supply circuit board is a multilayer board made of ceramic or resin.

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