JP2003150916A - Wireless communication device and control method thereof, storage medium, and computer program - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To prevent interference between wireless tag reader / writers. SOLUTION: By adding a function equivalent to a wireless tag to a wireless tag reader / writer, the wireless tag reader / writer itself behaves as a wireless tag in response to a request from another wireless tag reader / writer. Can be. Further, when a sleep request is received from an external wireless tag reader / writer, the wireless tag reader / writer is disabled in conjunction with prohibiting passive signal transmission in the wireless tag.
By prohibiting the active signal transmission in the writer, the interference of the request signal with another wireless tag reader / writer can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless communication device that operates in a relatively short-distance wireless communication area, a control method therefor, a storage medium, and a computer program. The present invention relates to a wireless communication device that performs contactless communication using a wireless tag having an operation characteristic of transmitting a radio wave corresponding to identification information or stored information, a control method therefor, a storage medium, and a computer program.

More specifically, the present invention relates to a wireless communication device equipped with a wireless tag and a wireless tag reader / writer function, a control method therefor, a storage medium, and a computer program, and a plurality of wireless communication devices are provided in the same wireless communication area. The present invention relates to a wireless communication device for preventing interference between wireless tag readers / writers in a mixed environment of wireless tags and wireless tag readers / writers, a control method therefor, a storage medium, and a computer program.

[0003]

2. Description of the Related Art Currently, a non-contact type radio frequency identification device (radio tag) is used in a system for managing entry and exit, an item identification system in physical distribution, a fee clearing system in a cafeteria, a CD or software. It is used in many systems, such as the unauthorized removal prevention system at retail stores.

A wireless tag is a device that includes unique identification information and a readable / writable storage area, and emits radio waves corresponding to the identification information and stored information in response to reception of radio waves of a specific frequency. It is possible to specify what it is by reading the identification information of the RFID tag or the information written in the storage area on the side of the reading device. Therefore, in the system using the identification information of the RFID tag and the information written in the storage area, the unique ID and other information written in the system can be used to determine the article or the owner. You can

For example, Japanese Unexamined Patent Publication No. 6-123773 discloses a radio frequency identification device which is manufactured in a small size by packaging an IC chip having transmission / reception and memory functions, a drive source for the chip, and an antenna. Has been done. According to this radio frequency identification device, various data relating to articles and the like are transmitted to the receiving means of the IC chip via the antenna, the output thereof is stored in the memory, and the data in the memory is read as necessary. , Can be supplied to the outside wirelessly via the antenna. Therefore, it is possible to quickly and easily confirm or track the existence or position of an article or the like.

By the way, such a wireless tag system is basically designed on the assumption that there is only one device for reading or writing to the wireless tag in the same wireless communication area. Therefore, in an environment where a plurality of wireless tags and wireless tag readers / writers coexist in the same wireless communication area, they interfere with each other and good wireless communication cannot be performed.

For example, a plurality of wireless tags respond to an access from one wireless tag reader / writer, or a plurality of wireless tag readers / writers try to access the same wireless tag. There is a possibility of getting stuck.

[0008] For example, in Japanese Patent Publication No. 2000-513841, in order to solve the problem that a plurality of RF / ID tags collide with each other when responding to a call from one RF / ID reader, a bit Deactivate a tag having a bitwise response different from a predetermined response of Wise, and selectively activate a tag having a predetermined response of bitwise. Due to
Disclosed is a method and apparatus for radio frequency identification tags that allows them to be unambiguously obtained from multiple tags.

As proposed in the above publication, when the wireless tag reader / writer deactivates or sleeps the wireless tag that is not the access partner, the responses from the wireless tags interfere with each other. Can be avoided.

However, in the case of the wireless tag with the reader / writer function as described above, even if it is possible to avoid the situation where the wireless tag goes into the sleep state and the responses interfere with each other, the reader / writer function thereof is avoided. There is still a problem that the request from the device interferes with other readers / writers.

The problem of communication interference in the same wireless communication area will be applicable to IC cards and IC card reader / writers known as contactless communication systems. The IC card performs communication by amplitude-modulating the signal appearing in the receiving circuit of the reader / writer by changing the load between its own antennas according to the response signal to the inquiry signal from the reader / writer.

[0012]

SUMMARY OF THE INVENTION An object of the present invention is to use a wireless tag having an operation characteristic of transmitting a radio wave corresponding to identification information or stored information in response to reception of a radio wave of a specific frequency. The present invention provides an excellent wireless communication device for performing non-contact communication by means of the above, a control method thereof, a storage medium, and a computer program.

A further object of the present invention is to provide an excellent wireless communication device which is equipped with both a wireless tag and a wireless tag reader / writer function and can operate favorably in a wireless communication area, a control method therefor, and a storage medium, And to provide a computer program.

A further object of the present invention is to prevent interference between wireless tag readers / writers in an environment where a plurality of wireless tags and wireless tag readers / writers coexist in the same wireless communication area. To provide an excellent wireless communication device and its control method, a storage medium, and a computer program.

[0015]

The present invention has been made in consideration of the above problems, and a first aspect thereof is a wireless communication device for transmitting and receiving wireless data, which is requested from the outside. A passive communication unit that receives a signal and returns a response signal to the signal, and an active communication unit that transmits a request signal to the outside and receives a response signal to the outside, and the passive communication unit has received the sleep request signal. The wireless communication device is characterized by falling into a sleep state in response to, and not responding to a request signal from the outside.

Further, a second aspect of the present invention is that a passive communication unit for receiving a request signal from the outside and returning a response signal thereto, and an active unit for transmitting the request signal to the outside and receiving a response signal thereto. With a communication unit,
A method of controlling a wireless communication device for transmitting and receiving wireless data, comprising the step of responding to the reception of a sleep request signal, wherein the passive communication unit falls into a sleep state and does not respond to a request signal from the outside. Is a method of controlling a wireless communication device.

According to the wireless communication device or the control method thereof according to the first or second aspect of the present invention, the same is true even when a plurality of wireless communication devices are mixed in the same wireless communication area. It is possible to avoid interference of response signals from the plurality of passive communication units with respect to the request signal.

The passive communication unit releases the sleep state in response to the reception of the sleep release request signal in the sleep state and resumes the response to the request signal from the outside.

While the passive communication unit is in the sleep state, the active communication unit is prohibited from transmitting the request signal. Therefore, even when a plurality of wireless communication devices coexist in the same wireless communication area, it is possible to prevent the request signals from the active communication units from interfering with each other.

Here, the active communication unit can be configured as a wireless tag reader which modulates a request signal and sends it out as a radio wave of a predetermined transmission frequency. Further, the passive communication unit can be configured as a wireless tag that recognizes a request signal received from the outside in a non-contact state.

That is, by adding a function equivalent to that of the wireless tag to the wireless tag reader, the wireless tag reader itself can behave as a wireless tag in response to a request from another wireless tag reader. . In such a case, the wireless communication device according to the first aspect of the present invention, when receiving a sleep request from an external wireless tag reader,
In conjunction with prohibiting passive signal transmission in the wireless tag, also prohibits active signal transmission in the wireless tag reader, thereby reducing interference of request signals with other wireless tag readers. be able to.

Alternatively, the active communication section can be configured as an IC card reader that receives a response signal by modulating a signal appearing according to a load variation between antennas in the passive communication section. Further, the passive communication unit can be configured as an IC card that changes a load between its own antennas according to a response signal to a request signal from the outside.

In such a case, the wireless communication device according to the first aspect of the present invention prohibits passive signal transmission in the IC card when a sleep request is received from an external IC card reader. By interlocking with this, by prohibiting the active signal transmission in the IC card reader, it is possible to reduce the interference of the request signal with other IC card readers.

Further, a third aspect of the present invention is that a passive communication unit for receiving a request signal from the outside and returning a response signal thereto, and an active unit for transmitting the request signal to the outside and receiving a response signal thereto. A storage medium that physically stores computer software in a computer-readable format that is described to execute control of a wireless communication device having a communication unit on a computer system, and the computer software is a sleep medium. In response to receiving the request signal, the passive communication unit falls into a sleep state and stops responding to an external request signal, and the passive communication unit sleeps in response to receiving the sleep release request signal. Releasing the state and restarting the response to the request signal from the outside, and the passive communication unit sleeps. During the state, which is a storage medium which is characterized by comprising the steps of prohibiting the transmission of the request signal by the active communication unit.

The storage medium according to the third aspect of the present invention is a medium for providing computer software in a computer-readable format to a general-purpose computer system capable of executing various program codes, for example. Such a medium is, for example, a DVD (Digital Vers
atile Disc), CD (Compact Disc), FD (FloppyDi)
sk), MO (Magneto-Optical disc), and other removable and portable storage media. Alternatively, it is technically possible to provide computer software to a specific computer system via a transmission medium such as a network (whether the network is wireless or wired).

The storage medium according to the third aspect of the present invention is a structural or functional cooperation between the computer software and the storage medium for realizing the function of predetermined computer software on a computer system. It defines the physical relationship. In other words, by installing the predetermined computer software in the computer system via the storage medium according to the third aspect of the present invention, the cooperative action is exerted on the computer system, and the first aspect of the present invention is achieved. It is possible to obtain the same effects as those of the wireless communication device or the control method thereof according to the first and second aspects.

Further, a fourth aspect of the present invention is to provide a passive communication unit for receiving a request signal from the outside and returning a response signal thereto, and an active unit for transmitting the request signal to the outside and receiving a response signal thereto. A computer program written to execute control of a wireless communication device having a communication unit on a computer system, wherein the passive communication unit is put into a sleep state in response to receiving a sleep request signal. A step of falling and not responding to a request signal from the outside, a step of restarting the response to the request signal from the outside by canceling the sleep state by the passive communication unit in response to receiving the sleep release request signal, Inhibiting the transmission of a request signal by the active communication unit while the passive communication unit is in a sleep state,
It is a computer program characterized by comprising.

A computer according to the fourth aspect of the present invention
The program defines a computer program written in a computer-readable format so as to realize a predetermined process on a computer system. In other words, by installing the computer program according to the fourth aspect of the present invention in the computer system, a cooperative action is exerted on the computer system, and each of the first and second aspects of the present invention. It is possible to obtain the same effects as those of the wireless communication device or the control method thereof.

Further objects, features and advantages of the present invention are as follows.
It will be apparent from the embodiments of the present invention described later and the more detailed description based on the accompanying drawings.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows a state of a wireless communication area in which the present invention is realized. In this wireless communication area, a plurality of wireless tags and a plurality of reader / writer devices are mixed. In the figure, reference numerals 1 and 2 are wireless tags, and reference numerals 3 and 4 are wireless tag readers / readers.
A writer. Hereinafter, when simply referred to as a “wireless tag reader / writer”, it is assumed to be a wireless communication device having both a wireless tag and a reader / writer function.

In the example shown in FIG. 1, the wireless tag reader / writer 3 sends a read or write request to the wireless tags 1 and 2 and the wireless tag reader / writer 4 existing in the same wireless communication area. , Showing how the response is being received. In this case, when viewed from the wireless tag reader / writer 3, the wireless tag reader / writer 4 behaves similarly to the wireless tags 1 and 2. That is, the wireless tag reader / writer 3 also recognizes the wireless tag reader / writer 4 as one of the wireless tags.

Further, in the example shown in the figure, in order to reduce interference with the RFID tag reader / writer 3,
As a reader / writer, the reader / writer 4 is restrained from sending an active transmission signal.

FIG. 2 schematically shows a hardware configuration of a wireless communication device 100 having both functions of a wireless tag and a reader / writer. Hereinafter, each part will be described with reference to FIG.

Reference numeral 101 is a non-volatile storage area, for example, an EEPROM (Electrically Erasable and
It is composed of a writable non-volatile memory device such as a programmable ROM) and an external storage device such as a hard disk device. The non-volatile storage area 101 is a control software storage area that holds a program code for controlling the operation of the wireless communication device 100, and the wireless communication device 100 behaves as a wireless tag (or other passive communication device). It has a virtual tag storage area that is sometimes used and other storage areas that can be used for general purposes.

Reference numeral 102 is a display unit having an output screen, which is composed of, for example, a liquid crystal display (LCD), and is used to display the operation and status of the wireless communication device 100.

Reference numeral 103 is a central processing unit (CPU) that centrally controls the operation of the entire wireless communication apparatus 100.
Processing Unit). Further, the reference number 104 is
A temporary storage area 104, which is a RAM (Random Access Me
mory) and rewritable volatile memory device. The CPU 103 executes the program code loaded from the control software storage area of the non-volatile storage area 101 onto the temporary storage area 104, and temporarily saves work data during program execution in the temporary storage area 104.

Reference numeral 105 is an input unit for the user to input operation commands, data and the like. Input section 1
Reference numeral 05 denotes, for example, a plurality of keys or buttons, or a touch panel superimposed on the display screen of the display unit 102.

Reference numeral 106 is a wireless communication unit, which is C
A functional module that performs wireless communication with the outside according to a command from the PU 103, and transmits a signal to and from a baseband block and a predetermined RF frequency signal to the antenna 10
An RF block for transmitting and receiving via 7 is provided. The wireless communication unit 106 is, for example, an FPGA (Field Programmable).
It can be configured by a general-purpose logic device such as a gate array) that allows the user to change the internal logic by a program after the completion of the IC.

In this embodiment, the wireless communication section 106 has a passive communication function for receiving a request signal from the outside and returning a response signal, and an active communication for transmitting the request signal to the outside and receiving the response signal from the outside. It has functions and. However, these details will be described later.

Reference numeral 108 is an external interface, which can be used to connect the wireless communication device 100 to a computer, other information equipment, and an information processing terminal. The external interface is, for example, Ether
rnet, RS232C, USB (Universal Serial B
us), IrDA, Bluetooth, IEEE 80
It can be configured with a standard interface such as 2.11b.

FIG. 3 schematically shows a functional configuration of the wireless communication section 106. As shown in the figure, the passive communication unit 106A that receives a request signal from the outside and returns a response signal
And an active communication unit 106B that transmits a request signal to the outside and receives a response signal from the outside.

The passive communication section 106A can receive request signals such as a sleep request and a sleep release request as well as a read request and a write request from the outside. When the read request is received, the request data stored in the virtual tag storage area of the nonvolatile storage area 101 is returned. When the write request is received, the request data is written in the virtual tag storage area of the nonvolatile storage area 101.

Further, the passive communication section 106A falls into the sleep state in response to the reception of the sleep request. In the sleep state, it does not respond to external read or write requests. For example, when a plurality of passive communication units 106A coexist in the same wireless communication area, the response from the passive communication unit 106A interferes with each other by setting a sleep state other than the specific passive communication unit 106A. The problem can be avoided. The sleep state continues until the sleep release request is received and the sleep is released.

The passive communication unit 106A holds its own state, that is, the sleep state or the sleep release state in the state holding unit 106C. Active communication unit 10
B can access the state holding unit 106C of the passive communication unit 106A.

On the other hand, the active communication section 106B can transmit request signals such as a sleep request and a sleep release request in addition to a read request and a write request to the outside, and can receive a response signal to this. By transmitting the sleep request, the passive communication unit 106A of the other party can transit to the sleep state, and by transmitting the sleep release request, the sleep state can be released.

Before transmitting the request signal, the active communication section 10B refers to the state holding section 106C in the passive communication section 106A to determine whether or not the passive communication section 106A is in the sleep state. Then, in the sleep state, the transmission of the request signal is disabled. This can avoid the problem that the request signals interfere with each other when a plurality of active communication units 10B coexist in the same wireless communication area.

As an example of a combination of the passive communication function and the active communication function, a radio tag having an operation characteristic of transmitting a radio wave corresponding to identification information or stored information in response to reception of a radio wave of a specific frequency. , Wireless tag reader / writer.

Here, a mechanism in which the wireless tag reader / writer as the active communication unit performs a read / write operation with respect to the wireless tag as the passive communication unit will be described with reference to FIG. In the illustrated example, an electromagnetic transfer system is used for wireless transmission and reception.

In the figure, reference numeral 11 is a wireless tag, which is composed of a tag chip 12 and an antenna 13.

The antenna 13 has a half-wavelength dipole
An antenna etc. is used. Also, the tag chip 12
Is a modulation unit 20, a rectification / demodulation unit 22, and a memory unit 23.
Composed of. The memory unit 23 corresponds to the virtual tag storage area (described above).

The radio wave fo transmitted from the RFID tag reader / writer 10 is received by the antenna 13 and input to the rectification / demodulation unit 22. Here, the radio wave fo is rectified and converted into a DC power source, and at the same time, the power source activates a demodulation function, and it is recognized that it is a read signal to the wireless tag 11. The generated power is stored in the memory unit 23.
It is also supplied to the modulator 20.

The memory section 23 reads information such as an ID stored in advance inside and sends it to the modulation section 20 as transmission data. The modulator 20 includes a diode switch 2
1, the diode switch 21 repeats the on / off operation depending on the transmission data. That is, when the data is 1, it is turned on and the antenna 13 is
It is terminated with an impedance (eg 50 ohms).

At this time, the wireless tag reader / writer 10
The radio wave from is absorbed by the wireless tag 11 side. Data is 0
In the case of, the switch is turned off, the diode switch 21 is opened, and at the same time, the terminal of the antenna 13 is also opened. At this time, the radio wave from the tag reader / writer 10 is reflected and returns to the transmission source.

Such a communication method is called a "back scatter method". In this way, the wireless tag 11 can send internal information to the wireless tag reader / writer 10 without power supply.

One of the RFID tag reader / writer 10 is
The tag reading module 14 and the antenna 15 connected to the tag reading module 14 are used and are connected to the host device 16 for use. The host device 16 is
For example, the CPU 103 in the wireless communication device 100, a personal computer or a PDA (Personal Digital Assis) connected via the external interface 108, and the like.
tant) and other information terminals, and provides a user interface for the user to perform interactive input.

The host device 16 first notifies the communication control unit 30 of the instruction to read the RFID tag 11 via the host interface unit 31.

The baseband processing unit 29 includes the communication control unit 3
When the tag read command from 0 is received, the transmitted data is edited and filtered, and then ASK is performed.
(Amplitude Shift Keying) Sends a baseband signal to the modulator 27. The ASK modulator 27 performs ASK modulation at the frequency fo of the frequency synthesizer 26.

The frequency setting of the frequency synthesizer 26 is
It is performed by the communication control unit 30. Generally, a wireless tag 1
The transmission frequency to the wireless tag 11 is used by hopping in order to reduce the standing wave and multipath of the signal from 1. This communication hopping instruction is also given by the communication control unit 30. The transmission signal that has been ASK-modulated passes through the circulator 24 and is transmitted from the antenna 15 to the wireless tag 11
Is emitted toward.

As described above, the reflected signal from the wireless tag 11 returned by the back scatter method has the same frequency as the signal transmitted from the wireless tag reader / writer 10. This signal is sent to the RFID tag reader / writer 10
The signal is received by the antenna 15 and input to the mixer 25.

Since the same local frequency fo as that at the time of transmission is input to the mixer 25, a signal modulated on the wireless tag 11 side appears at the output of the mixer 25.

The demodulator 28 demodulates this signal into 1/0 data and sends it to the baseband processor 29. The baseband processing unit 29 decodes the data and extracts the data stored in the memory unit 23 in the wireless tag 11. This data, according to the instruction of the communication control unit 30,
It is transferred from the host interface unit 31 to the host device 16.

As described above, the wireless tag reader / writer 10 can read the information in the wireless tag 11. Further, the wireless tag reader / writer 10 can perform the write operation to the wireless tag 11 by the same operation as described above. In this case, the designated data on the host device 16 side can be written in the memory unit 23 (that is, the virtual tag storage area) in the wireless tag 11.

As another example of the combination of the passive communication function and the active communication function, the load of the reader / writer is changed by changing the load between the antennas of the reader / writer according to the response signal to the request signal from the reader / writer. A non-contact IC card and an IC card reader / writer that perform communication by applying amplitude modulation to a signal appearing in a circuit can be mentioned.

Wireless communication between the IC card and the IC card reader / writer is realized, for example, based on the principle of electromagnetic induction. FIG. 5 shows an IC card and an IC based on electromagnetic induction.
It conceptually illustrates the wireless communication mechanism of the card reader / writer. The IC card reader / writer includes an antenna L _RW composed of a loop coil, and a current I _{RW is} passed through the antenna L _RW to generate a magnetic field around it. On the other hand, on the IC card side, a loop coil L _c is electrically formed around the IC card. An induced voltage is generated at the end of the loop coil L _c on the IC card side by the magnetic field generated by the loop antenna L _c on the side of the IC card reader / writer, and the terminal of the IC card connected to the end of the loop coil L _c is generated. Is entered.

The antenna L _RW on the IC card reader / writer side and the loop coil L _c on the IC card side form a single transformer as a system, although the degree of coupling varies depending on their positional relationship. The read / write operation of the IC card can be modeled as shown in FIG.

On the IC card reader / writer side, by modulating the current I _RW flowing through the antenna L _RW , the voltage V _O induced in the loop coil L _c on the IC chip is modulated, and Utilizing this, the IC card reader / writer can send data to the IC card.

Further, the IC card has a function (Load Switchin) of varying the load between the terminals of the loop coil L _c in accordance with the data to be returned to the IC card reader / writer.
g). When the load between the terminals of the loop coil L _c fluctuates, the impedance between the antenna terminals on the IC card reader / writer side changes, which appears as fluctuations in the passing current I _RW and the voltage V _RW of the antenna L _RW. . By demodulating this fluctuation, the IC card reader / writer can receive the return data of the IC card.

That is, the IC card changes the load between its own antennas according to the response signal to the request signal from the IC card reader / writer, thereby amplitude-modulating the signal appearing in the receiving circuit on the card reading / writing device side. It is possible to communicate by spending time.

FIG. 7 shows a signal reception processing operation in radio communication apparatus 100 in the form of a flowchart.
This operation enables the wireless communication device to behave as a passive communication function such as an ordinary wireless tag (or IC card). For example, the CPU 103 executes control software stored in the nonvolatile storage area 101. It is realized in the form of execution. Alternatively, it can be realized by a logic implemented in a baseband block in the wireless communication unit 106 configured by FPGA or the like. Hereinafter, the signal reception process in the wireless communication device 100 will be described with reference to this flowchart.

When the signal receiving process is activated in the wireless communication device 100, first, in step S1, the sleep state is initialized to off. Then, after this, step S
At 2, the signal waits.

In the signal reception waiting state, the wireless communication device 100 receives a response signal from a passive communication function such as an external wireless tag (or IC card), or a wireless tag reader / writer (or IC card reader / writer). When a request signal is received from an active reception function such as a writer), the process proceeds to step S3 and the sleep state is determined.

When it is determined in the decision block S3 that the sleep state is ON, the process proceeds to step S4, and it is further determined whether or not the received signal is a sleep release request. If the signal is a signal other than the sleep release request, the wireless communication device 100 in the sleep returns to step S2 without performing any processing and waits for the next signal reception.

On the other hand, if it is determined in step S4 that the request is a sleep release request, the process proceeds to the next step S5 to set the sleep state to OFF, and then to step S2.
Return to and wait for the next signal.

When the processing in step S5 is performed, the wireless communication device 100 is released from the sleep state and is ready to respond to various requests as a passive communication function such as a wireless tag (or IC card). Wireless tag reader / writer (or IC card
As a reader / writer, it becomes ready to send various requests.

If it is determined in decision block S3 that the sleep state is off, step S
The signal received in step 6 is a request signal from an active communication function such as another wireless tag reader / writer (or IC card reader / writer), or another wireless tag (or IC card) It is determined whether it is a response signal from a passive communication function such as.

If it is determined in the decision block S6 that the request signal is from an active communication function such as another RFID tag reader / writer (or IC card reader / writer), the operation proceeds to step S7. Further, it is determined whether or not the received signal is a sleep request.

When it is determined in the decision block S7 that the sleep request is issued, the sleep state is set to ON in the next S8, and then the process returns to the step S2 to wait for the next signal reception.

When the processing of step S8 is performed, the wireless communication device 100 does not respond to various requests as a passive communication function of a wireless tag (or IC card) until the sleep state is released, and Wireless tag reader / writer (or IC card reader /
It does not send various requests as an active communication function such as a writer).

If it is determined in the decision block S7 that the received signal is other than the sleep request, the process proceeds to step S10, where the wireless communication section 106 has a passive communication function such as a wireless tag (or IC card). Behavior, that is, request reception processing is performed. Then, it returns to step S2 and waits for the next signal reception. Regarding the request receiving process in step S10, due to space limitations, a separate description will be given.
This will be described with reference to FIG.

In decision block S6, the received signal is
Other wireless tag reader / writer (or IC card
When it is determined that it is not a request signal from an active communication function such as a reader / writer, that is, when it is determined that it is a response signal from a passive communication function such as another wireless tag (or IC card) , Go to step S9,
It behaves as an active communication function of a wireless tag reader / writer (or IC card reader / writer), that is, a response reception process. Then, it returns to step S2 and waits for the next signal reception. The response reception process in step S9 will be described separately with reference to FIG. 8 due to space limitations.

FIG. 8 shows, in the form of a flowchart, the procedure of the response receiving process in step 9 in the flowchart shown in FIG. In this response reception process, the wireless communication device 100 performs wireless tag reader / writer (or I
This corresponds to the behavior as an active communication function of a C card reader / writer). This response reception process is, for example,
It is realized in a form in which the CPU 103 executes the control software stored in the non-volatile storage area 101.
Alternatively, it can be realized by a logic implemented in a baseband block in the wireless communication unit 106 configured by FPGA or the like. Hereinafter, the response reception process of the wireless communication device 100 will be described with reference to this flowchart.

After starting the response signal receiving process, the radio communication device 100 creates a response result, returns the process to the procedure of the caller (step S21), and ends the response receiving process.

Further, FIG. 9 shows, in the form of a flowchart, the procedure of the request receiving process in step 10 in the flowchart shown in FIG. This request reception process corresponds to the behavior of the wireless communication device 100 as a passive communication function such as a wireless tag (or IC card).
The request receiving process is realized, for example, in a form in which the CPU 103 executes the control software stored in the non-volatile storage area 101. Alternatively, it can be realized by a logic implemented in a baseband block in the wireless communication unit 106 configured by FPGA or the like. The request reception process of the wireless communication device 100 will be described below with reference to this flowchart.

First, in step S31, it is determined whether or not the received request is an ID identification request. If it is an ID identification request, the process proceeds to step S32 to execute the ID identification processing. The ID identification process is to read the ID of the passive communication function such as the wireless tag. In this embodiment, the ID is read from the virtual tag storage area of the non-volatile storage area 101 and sent to the request source.

If the received request is not the ID identification request, then in step S34, it is determined whether or not the request is a write request. If it is a write request,
In step S35, the writing process is executed. The writing process in this embodiment is to write the requested information at the requested position in the virtual tag storage area in the nonvolatile storage area 101 shown in FIG.

If the received request is not a write request, then in step S36, it is determined whether or not it is a read request. If the request is a read request, the process proceeds to step S37 to execute the read process. The reading process in this embodiment is to read the information held in the virtual tag storage area in the non-volatile storage area 101 shown in FIG. 2 from the requested position in the requested size.

After processing these received requests,
In step S33, a response signal is transmitted to the request source, and the entire processing routine ends.

Further, FIG. 10 shows, in the form of a flowchart, a processing procedure for the radio communication apparatus 100 to perform a signal transmission process. According to this processing procedure,
When acting as an active communication function of a reader / writer (or IC card reader / writer), etc., depending on the state of passive communication function of a wireless tag (or IC card) (that is, whether it is in sleep state or not) The active request signal transmission processing is restricted.

This processing procedure is realized, for example, in the form that the CPU 103 executes the control software stored in the non-volatile memory area 101. Or FP
It can also be realized by a logic implemented in a baseband block in the wireless communication unit 106 configured by GA or the like. The signal transmission process in the wireless communication device 100 will be described below with reference to this flowchart.

The wireless communication device 100 has a nonvolatile storage area 1
When various request signals are transmitted by the operation of the control software stored in 01, it is first determined in step S41 whether the passive communication function unit 106A such as a wireless tag (or IC card) is in a sleep state. Determine.

If it is determined that the request signal is not in the sleep state, there is no concern that the request signals will interfere with other wireless communication devices, and the process proceeds to step S42 and the request signal transmission is executed as it is.

On the other hand, in decision block S41, the passive communication function unit 10 such as a wireless tag (or IC card) is used.
If 6A is determined to be in the sleep state, in order to limit signal transmission and avoid interference with other request signals, the process proceeds to step S43, the response result is set to sleep, and The processing routine ends.

Table 1 below summarizes the request signals used between the wireless communication devices composed of the wireless tag and the wireless tag reader / writer device. The wireless communication device 100 according to the above-described embodiment of the present invention needs to have at least a function of transmitting these request signals. Request signals other than those shown here may be added or changed as necessary.

[0095]

[Table 1]

Table 2 below summarizes response signals used between wireless communication devices composed of a wireless tag and a wireless tag reader / writer device. The wireless communication device 100 in the above-described embodiment of the present invention needs to have at least a function of transmitting these response signals. Response signals other than those shown here may be added or changed as necessary.

[0097]

[Table 2]

[Supplement] The present invention has been described in detail with reference to the specific embodiments. However, it is obvious that those skilled in the art can modify or substitute the embodiments without departing from the scope of the present invention. That is, the present invention has been disclosed in the form of exemplification, and the contents of this specification should not be construed in a limited manner. In order to determine the gist of the present invention, the section of the claims described at the beginning should be taken into consideration.

[0099]

As described above in detail, according to the present invention,
An excellent wireless communication device and its control for performing non-contact communication using a wireless tag having an operating characteristic of transmitting a radio wave corresponding to identification information or stored information in response to reception of a radio wave of a specific frequency A method, a storage medium, and a computer program can be provided.

Further, according to the present invention, an excellent wireless communication device equipped with both a wireless tag and a wireless tag reader / writer function and capable of suitably operating in a wireless communication area, a control method thereof, a storage medium, Also, a computer program can be provided.

Further, according to the present invention, it is possible to prevent interference between wireless tag readers / writers in an environment where a plurality of wireless tags and wireless tag readers / writers coexist in the same wireless communication area. It is possible to provide an excellent wireless communication device and its control method, a storage medium, and a computer program.

According to the present invention, the wireless tag and the wireless tag
In a wireless communication system including a reader / writer, by adding a function equivalent to that of a wireless tag to a wireless tag reader / writer, the wireless tag reading / writing device itself is a wireless tag in response to a request from another wireless tag reading / writing device. Can behave as. In addition, when a sleep request is received from an external RFID tag reader / writer, the passive signal transmission of the RFID tag is prohibited, and the active signal transmission of the RFID tag reader / writer is also prohibited. By doing so, it is possible to reduce the interference of the request signals with other RFID tag readers / writers.

Further, according to the present invention, the above effect can be obtained without making any particular change in the wireless standard between the wireless tag and the wireless tag / reader / writer, so that the mounting cost can be greatly reduced. .

[Brief description of drawings]

FIG. 1 is a diagram showing a state of a wireless communication area in which the present invention is realized.

FIG. 2 is a diagram schematically showing a hardware configuration of a wireless communication device 100 having both functions of a wireless tag and a reader / writer.

FIG. 3 is a block diagram schematically showing a functional configuration of a wireless communication unit 106.

FIG. 4 is a diagram for explaining a mechanism in which a wireless tag reader / writer as an active communication unit performs a read / write operation on a wireless tag as a passive communication unit.

FIG. 5 is a diagram conceptually showing a mechanism of wireless communication between an IC card and an IC card reader / writer based on electromagnetic induction.

FIG. 6 is a diagram modeling a read / write operation of an IC card.

FIG. 7 is a diagram showing a signal reception processing operation in the wireless communication device 100 in the form of a flowchart.

8 is a flowchart showing a procedure of a response receiving process in step 9 in the flowchart shown in FIG.

FIG. 9 is a step S1 in the flowchart shown in FIG.
6 is a flowchart showing a procedure of a request receiving process in 0.

FIG. 10 is a flowchart showing a processing procedure for the wireless communication device 100 to perform signal transmission processing.

[Explanation of symbols]

100 ... Wireless communication device 101 ... Nonvolatile storage area 102 ... Display unit 103 ... CPU 104 ... Temporary storage area 105 ... Input section 106 ... Wireless communication unit 107 ... antenna 108 ... External interface

Claims (12)

[Claims] 1. A wireless communication device for transmitting and receiving wireless data, comprising: a passive communication unit that receives a request signal from the outside and returns a response signal to the request signal; and a passive communication unit that transmits the request signal to the outside and a response signal to the outside. A wireless communication device, comprising: an active communication unit for receiving, wherein the passive communication unit falls into a sleep state in response to receiving a sleep request signal and does not respond to a request signal from the outside. 2. The wireless communication system according to claim 1, wherein the passive communication unit releases the sleep state and resumes a response to a request signal from the outside in response to receiving the sleep release request signal. Communication device. 3. The wireless communication device according to claim 1, wherein the active communication unit is prohibited from transmitting a request signal while the passive communication unit is in a sleep state. 4. The active communication unit is a wireless tag reader that modulates a request signal and sends it as a radio wave of a predetermined transmission frequency, and the passive communication unit receives a request signal received from the outside in a non-contact state. The wireless communication device according to claim 1, wherein the wireless communication device is a wireless tag to be recognized. 5. The active communication section is an IC card reader that receives a response signal by modulating a signal that appears according to a load variation between antennas in the passive communication section, and the passive communication section is an external device. The wireless communication device according to claim 1, wherein the wireless communication device is an IC card that changes a load between its own antennas according to a response signal to a request signal from the device. 6. Wireless data, comprising: a passive communication unit that receives a request signal from the outside and returns a response signal to the request signal; and an active communication unit that sends the request signal to the outside and receives a response signal to the request signal. A method of controlling a wireless communication device for transmitting and receiving a wireless communication device, comprising the step of: in response to receiving a sleep request signal, the passive communication unit falls into a sleep state and does not respond to a request signal from the outside. A method for controlling a wireless communication device. 7. The method according to claim 6, further comprising the step of releasing the sleep state and restarting a response to a request signal from the outside by the passive communication unit in response to receiving the sleep release request signal. A method for controlling a wireless communication device according to claim 1. 8. The method of controlling a wireless communication device according to claim 6, further comprising the step of prohibiting transmission of a request signal by the active communication unit while the passive communication unit is in a sleep state. 9. The active communication unit is a wireless tag reader that modulates a request signal and sends it as a radio wave of a predetermined transmission frequency, and the passive communication unit receives a request signal received from the outside in a non-contact state. The wireless communication device control method according to claim 6, wherein the wireless communication device is a wireless tag to be recognized. 10. The active communication unit is an IC card reader that receives a response signal by modulating a signal that appears according to a load variation between antennas in the passive communication unit, and the passive communication unit is an external device. 7. The method of controlling a wireless communication device according to claim 6, wherein the IC card is an IC card that changes a load between its own antennas according to a response signal to a request signal from the device. 11. A wireless communication apparatus comprising: a passive communication unit that receives a request signal from the outside and returns a response signal to the request signal; and an active communication unit that transmits the request signal to the outside and receives a response signal to the outside. A storage medium physically storing in a computer-readable format computer software written to perform the control of a computer system in response to receiving a sleep request signal. The passive communication unit falls into a sleep state and does not respond to a request signal from the outside, and the passive communication unit releases the sleep state and receives an external request in response to receiving a sleep release request signal. Restarting a response to a signal, and the active communication unit while the passive communication unit is in a sleep state. Storage medium characterized by comprising the steps of prohibiting the transmission of the request signal by. 12. A wireless communication device comprising: a passive communication unit that receives a request signal from the outside and returns a response signal to the request signal; and an active communication unit that transmits the request signal to the outside and receives a response signal to the request signal. Is a computer program written to execute control of the above in a computer system, wherein the passive communication unit falls into a sleep state in response to receiving a sleep request signal and responds to an external request signal. During the sleep state, the passive communication unit releases the sleep state and resumes a response to a request signal from the outside in response to receiving the sleep release request signal; And a step of prohibiting transmission of a request signal by the active communication unit. Grams.