JP2006081105A - Individual object recognition wireless device and system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive and low power consumption type solid-state object recognition wireless device and system without the need for linking databases under network environment. <P>SOLUTION: A tag 1 is worn by a recognized object and used for recognition of the recognized object. The tag 1 comprises first communicating means 111-114, a memory 115, second communicating means 127-129, and a battery 125. The first communicating means 111-114 are a passive type communicating means for transmitting/receiving information to and from an external reader/writer by 2.45GHz short-distance bidirectional radio communications. The storage content of the memory 115 is rewritten by means of the first communicating means. The second communicating means 127-129 transmits data continuously to an external apparatus by 300MHz broad band unidirectional radio communications, based on the storage content of the memory 115. The Battery 125 supplies electric power to the second communicating means and the memory at least. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a tag-like or label-like solid-state recognition radio apparatus (RFID) and system mounted on an object to be identified, and more particularly to an RFID apparatus and system having both passive and active functions. .

  Conventionally, this type of RFID device is mounted on an identification object in the form of a wireless IC tag, for example, and used for logistics management, station entrance / exit management, and the like. RFID devices are roughly classified into a passive type and an active type.

  A passive RFID device does not have a built-in battery, generates electric power required internally by radio waves from an external reader / writer, and communicates with the reader / writer in response to a call from the reader / writer. Although the communication range cannot be made large and is about 1 m, it can be downsized and the operation can be made permanent.

  On the other hand, an active RFID device incorporates a battery inside and transmits information to an external receiver. Because it has a built-in battery, the communication range is as wide as 10 to 20m, but it has a drawback in that it cannot be downsized because it has a built-in battery, and there is a life of the battery. Various applications can be considered by using the functions well.

Patent Document 1 is a prior art of passive RFID, and Patent Document 2 is a prior art of active RFID.
JP-T-2004-506907, paragraphs 0003 and 0004 JP 2003-226434 A, paragraph 0014

  When an attempt is made to construct a zone detection type RFID system, use of an active type RFID is generally considered. However, if a transmission / reception circuit is mounted so as to be readable and writable in an active type, the circuit scale and power consumption increase, so that the battery life is shortened and the cost is increased.

  On the other hand, considering the use of a passive type capable of reading and writing, the communication range between the passive type interrogator (reader / writer) and the responder (tag) is a few meters long, so the target (responder) is asked to The interrogator must always search in some way to see if it is in the communication area with the instrument, and the interrogator must be spread over the entire zone to be detected, or the zone must be detected with strong radio waves There are many elements that are impossible in reality.

  Therefore, considering the sharing of the passive type and the active type, since each has a different ID system, the database must be associated in the network environment.

  The present invention has been made in view of such problems, and it is an object of the present invention to provide a solid-state recognition wireless device and system that are inexpensive and have low power consumption without the need for database linkage in a network environment. To do.

  A solid-state recognition wireless device according to the present invention is used for identification of an identification target, and is a passive type first device that transmits and receives information to and from an external reader / writer by bidirectional wireless communication in a first frequency band. 1 communication means, a rewritable memory whose contents are rewritten by the first communication means, and data is continuously transmitted to an external device by unidirectional wireless communication in the second frequency band based on the storage contents of the memory. Active type second communication means for transmitting the power, and power supply means for supplying power to at least the second communication means and the memory.

  The power supply means is, for example, a rechargeable battery. In this case, a charging means for charging the battery by radio waves of bidirectional wireless communication by the first communication means may be provided. However, the power supply means in the present invention is not limited to such a rechargeable battery, and may be, for example, a primary battery, a large-capacity capacitor, or an AC adapter that introduces power from the outside.

  The solid-state recognition wireless system according to the present invention performs solid-state wireless communication with the solid-state recognition wireless device mounted on the identification target as described above, and the first communication unit of the solid-state recognition wireless device to store the memory in the memory. A reader / writer for writing information necessary for communication by the second communication means; a receiving means for receiving data transmitted by the second communication means; and the identification object based on the data received by the receiving means And an information processing device for identifying the device.

  According to the present invention, an inexpensive device with low power consumption can be constructed by merging a passive type and an active type and making the receiving side passive. Further, by sharing the memory between the transmission / reception side and the transmission side, it is not necessary to perform database linkage in a network environment, and prompt operation is possible.

  In addition, if a rechargeable power source is built in, it can be appropriately charged from the first communication means side, so that the battery life that has been a problem of the active type identification device can be made semi-permanent.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram showing a configuration of an identification system using an RFID device according to an embodiment of the present invention.

  This identification system includes a tag 1 as an RFID device that is mounted on a recognition target, for example, a pallet for conveying goods or goods, and a first frequency band for this tag 1, for example, several GHz. A reader / writer 2 for reading / writing information by 45 GHz wireless communication, a terminal device 3 connected to the reader / writer 2, and information transmitted from the tag 1 in a second frequency band, for example, several KHz to several The receiver 4 is configured to include a receiver 4 that receives radio communication of 100 MHz, more preferably UHF band, in this example, 300 MHz, and a terminal device 5 connected to the receiver 4.

  As shown in FIG. 2, the tag 1 is composed of a 2.45 GHz transceiver 11 constituting a passive RFID and a 300 MHz transmitter 12 constituting an active RFID.

  The 2.45 GHz transceiver 11 is configured as follows. A first antenna 111 and a second antenna 112 are provided for transmitting and receiving with the external reader / writer 2 in the form of, for example, a loop-shaped printed circuit. An analog / transmission function for performing data communication with the reader / writer 2 via these antennas 111 and 112, and a power supply function for generating a constant voltage by rectifying and boosting 2.54 GHz radio waves. A front end (hereinafter referred to as “AFE”) circuit 113 is provided. Data received via the AFE circuit 113 is stored in the memory 115 via the controller 114. The memory 115 is a rewritable nonvolatile storage medium such as a flash memory, for example, and necessary information such as transmission data from the transmitter 12 and transmission control information (information such as transmission interval, transmission time, transmission stop condition). Remember. The controller 114 controls not only data exchange between the AFE circuit 113 and the memory 115 but also data exchange between the memory 115 and the transmitter 12. Here, the antennas 111 and 112, the AFE circuit 113, and the controller 114 constitute a first communication unit. The power supply circuit 116 has a function of switching power to be supplied to the controller 114 and the memory 115 between a period in which the antennas 111 and 112 receive 2.45 GHz radio waves and a non-reception period.

  The 300 MHz transmitter 12 is configured as follows. The voltage supplied from the power supply circuit 116 during the period of receiving the 2.45 GHz radio wave on the transceiver 11 side is supplied to the power supply circuit 122 via the diode 121, and the 2.45 GHz radio wave is supplied on the transceiver 11 side. During a period of no reception, the power supply voltage from the power supply circuit 116 is supplied to the power supply circuit 116 on the transceiver 11 side via the diode 123. The switch circuit (P_OUT) 124 has a function of switching the power supply in this way. A rechargeable battery 125 is connected to the power supply circuit 122. When power is supplied from the transceiver 11 side, the battery 125 is charged. When power is not supplied, the battery 125 is charged. The power supply voltage from 125 is supplied to the transceiver 11 side. On the transmitter 12 side, a controller 127, an analog front end (AFE) circuit 128, and an antenna 129 are also provided. The controller 127 communicates with the controller 114 on the transceiver 11 side, reads the data stored in the memory 115, and transmits the data to the external receiver 4 via the AFE circuit 128 and the antenna 129. Here, the controller 127, the AFE circuit 128, and the antenna 129 constitute second communication means.

  In addition, by configuring the transmitter / receiver 11 and the transmitter 12 as passive RFID and active RFID, respectively, existing individual circuits can be used as they are, but the controllers 114 and 127 are Needless to say, it may be configured as one controller.

Next, the operation of the identification system according to this embodiment configured as described above will be described.
(1) When the tag 1 is in the communication range of the reader / writer 2 FIG. 3 is an operation flowchart of the transceiver 11 when the tag 1 is in the communication range with the reader / writer 2, and FIG. 12 is an operation flowchart of the machine 12.

  At this time, the transceiver 11 detects the 2.45 GHz radio wave transmitted from the reader / writer 2 (S11). The AFE circuit 113, for example, rectifies and boosts the radio wave detected on the antenna 112 side, makes it constant voltage, supplies it to the AFE circuit 113, the controller 114, and the memory 115 to make them operable, and sets the power circuit 116 to Power is supplied to the power supply circuit 122 on the transmitter 12 side. The power supply circuit 122 constantly monitors the voltage from the transmitter / receiver 116 side. When the monitored voltage exceeds a predetermined voltage, the power supply circuit 122 turns off the switch circuit 124 and stops supplying the power supply voltage to the transmitter / receiver 11 side (S21). ).

  The radio wave from the reader / writer 2 is, for example, ASK modulated, and the AFE circuit 113 demodulates the received signal by the internal detection circuit and simultaneously extracts the clock. A transmission frame from the reader / writer 2 includes, for example, a frame pulse, a command frame pulse, a command completion, and a response frame pulse. The command frame pulse includes loading to various registers in the controller 114, a sleep command, and reading from the register. And a program for instructing writing to the memory 115. The controller 114 decodes the command frame pulse, and the response is returned with a response on the reflected wave in the response frame pulse portion. For example, the antenna 111 may be responsible for returning this response, and the antenna 112 may be responsible for the reception side and the power generation side. FSK modulation and PSK modulation may be used for the modulation from the reader / writer 2 and the modulation used for the response of the tag 1. As described above, in the passive type transceiver 11, communication is always performed following transmission from the reader / writer 2 and returning a response thereto.

  If a program command for instructing writing is received (S12), the controller 114 writes the data (transmission data, transmission control information, etc.) in the memory 115 (S13). The data to be written includes transmission data transmitted from the transmitter 12 side, data specifying the transmission interval, and the like.

On the other hand, while the transmitter 12 is detecting the 2.45 GHz radio wave, the sleep state is maintained (S22, S23, S24). If the 2.45 GHz radio wave is not detected, the switch circuit 124 is turned on. The power supply voltage Vcc from the battery 125 is supplied to the transceiver 11 side in the on state (S25).
(2) When the tag 1 is outside the communication range of the reader / writer 2 FIG. 5 is an operation flowchart of the transmitter 12 when the tag 1 is outside the communication range with the reader / writer 2.

  First, the circuit 124 is turned on to supply the power supply voltage Vcc from the battery 125 to the transceiver 11 side (S31). Thereby, the operations of the controller 114 and the memory 115 on the transceiver 11 side are ensured via the power supply circuit 116. Next, the controller 127 communicates with the controller 114 and reads the transmission data stored in the memory 115 (S32). Similarly to the transmission frame transmitted from the reader / writer 2 to the controller 114, the transmission frame transmitted from the controller 127 to the controller 114 may be composed of a frame pulse, a command frame pulse, a command completion, and a response frame pulse. it can. Data read from the memory 115 is superimposed on the command completion pulse and sent to the controller 127 side. Subsequently, after the switch circuit 124 is turned off and the power supply to the transceiver 11 is stopped (S33), the data to be transmitted among the read data is transmitted via the AFE circuit 128 and the antenna 129. It is transmitted to the outside (S34). The transmission signal is a 300 MHz ASK, FSK or PSK modulated signal having a communication range of about 10 m. The receiver 4 can receive transmission data from the tag 1 over a relatively wide range.

  After that, if the 2.45 GHz radio wave is not detected (S35, S36), the sleep state is maintained until the transmission interval set in the memory 115 expires (S37), and when the transmission interval expires, data transmission is performed again. Is repeated (S38, S34). If a 2.45 GHz radio wave is detected in this state (S35, S36), the process proceeds to the transceiver 11 side.

  As described above, when the transmitter 12 is transmitting data stored in the memory 115, communication on the side of the transmitter / receiver 11 is suppressed, and functions necessary for the electric field strength detection operation at 2.45 GHz in the AFE 113 circuit. The functions other than the function of reading from the memory 115 are not operated. This is because the transmitter / receiver 11 that has received the 2.45 GHz radio wave starts a write operation to the memory 115 while the transmitter 12 is transmitting data, and the 2.45 GHz signal collides with the 300 MHz signal. This is to prevent the data writing from being abnormally terminated and the stored contents of the memory 115 from being destroyed.

  According to the identification system according to the present embodiment, every time the tag 1 enters the communication range of the reader / writer 2, the transmission data can be updated and transmitted to the outside in real time. It is possible to construct an advanced identification system that detects other information in real time on the center side.

  In addition, since a rechargeable power source is built in and can be appropriately charged from the transceiver 11 side, the battery life that has been a problem of the active tag can be made semi-permanent.

It is a figure which shows the structure of the identification system which concerns on one Embodiment of this invention. It is a block diagram of the tag used with the identification system. It is a flowchart which shows the operation | movement of the transmitter / receiver within the reader / writer communication range in the tag. It is a flowchart which shows operation | movement of the transmitter within the reader / writer communication range in the same tag. It is a flowchart which shows operation | movement of the transmitter out of the reader / writer communication range in the same tag.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Tag, 2 ... Reader / writer, 3, 5 ... Terminal device, 4 ... Receiver, 11 ... Transmitter / receiver, 12 ... Transmitter, 111, 112, 129 ... Antenna, 113, 128 ... Analog front end ( AFE) circuit, 114, 127 ... controller, 115 ... memory, 116, 122 ... power supply circuit, 125 ... battery.

Claims (7)

A passive first communication means for transmitting / receiving information to / from an external reader / writer by two-way wireless communication in a first frequency band;
A rewritable memory whose stored contents are rewritten by the first communication means;
Active second communication means for continuously transmitting data to an external device by unidirectional wireless communication in a second frequency band based on the storage content of the memory;
Power supply means for supplying power to at least the second communication means and the memory,
A solid-state recognition wireless device used for identification of an identification target.   2. The fixed recognition wireless device according to claim 1, wherein the first wireless communication unit performs short-range wireless communication, and the second wireless communication unit performs wide-area wireless communication. The power supply means is a rechargeable battery,
3. The solid-state recognition wireless device according to claim 1, further comprising charging means for charging the battery by radio waves of bidirectional wireless communication by the first communication means.   The solid-state recognition wireless device according to any one of claims 1 to 3, wherein the first frequency band and the second frequency band are different from each other. The second communication means monitors whether the first communication means is receiving a signal of the first frequency band;
When the first communication means is receiving the signal of the first frequency band, the second communication means is put into a dormant state, and the first communication means is a signal of the first frequency band. Is not received, the first communication unit is put into a dormant state, and the second communication unit is configured to supply power necessary for communication in the second communication unit from the power supply unit. The solid-state recognition wireless device according to any one of claims 1 to 4, wherein the communication is performed by the wireless communication device.   The solid-state recognition wireless device according to any one of claims 1 to 5, wherein the storage content of the memory includes transmission data and transmission control information of the second communication unit. The solid recognition wireless device according to any one of claims 1 to 6, which is attached to the identification target;
A reader / writer that performs wireless communication with the first communication unit of the solid-state recognition wireless device and writes information necessary for communication by the second communication unit to the memory;
Receiving means for receiving data transmitted by the second communication means;
A solid-state recognition wireless system comprising: an information processing device that identifies the identification target based on data received by the receiving means.

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