JP2001127672A - Data communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a data communication system that enriches the function of a data carrier not having a battery. SOLUTION: A relay reader/writer 14 is provided in a case 16 that contains the data carrier 10 removably. The relay reader/writer 14 has a power source and can read/write data to/from the data carrier 10 and data communication is attained between the data carrier 10 and a main body reader/writer via the relay reader/writer 14 to extend the communication distance. Furthermore, the relay reader/writer 14 has an LCD 63 and a ten-key 62 for a display function and an input function.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data communication system for performing non-contact data communication between a data carrier having a non-volatile memory and operated by a voltage induced by a received signal and a main body reader / writer.

[0002]

2. Description of the Related Art A conventional data communication system is shown in FIG. In the figure, 10 is a data carrier and 12 is a main body reader / writer. The data carrier 10 includes a transmitting / receiving coil L1, a capacitor C1 forming a resonance circuit with the transmitting / receiving coil L1, a transmitting / receiving circuit 22 having an amplifier, a power supply circuit 23, a demodulator 24, a modulator 25, a control circuit 26, and a memory 27. I have. The main body reader / writer 12 includes a transmission coil L2, a reception coil L3,
Capacitors C2 and C3, amplifiers 35 and 36, modulator 3
7, a demodulator 38, and a control circuit 39. The control circuit 39 is connected to a host computer 40.

A signal modulated at the carrier frequency f1 from the main body reader / writer 12 is guided from the transmission coil L2 to the transmission / reception coil L1 of the data carrier 10, and the power supply circuit 2
3, the rectified and smoothed DC power is obtained. At the same time, demodulator 2
4 demodulates the received signal, and the control circuit 26 performs processing such as reading data at a predetermined address stored in the memory 27 or writing data to the predetermined address in accordance with a command included in the signal. The data read from the memory 27 is modulated by the modulator 25 at a carrier frequency of (1/2) · f1 and applied to the transmission / reception coil L1. This modulated signal is received by the receiving coil L3 of the main body reader / writer 12, and is received by the demodulator 38.
And transmitted to the host computer 40 via the control circuit 39. The memory 27 is a non-volatile memory such as an EEPROM, and retains data even when no DC power is generated.

As described above, the conventional data carrier does not have a power source such as a battery, but operates by using the voltage induced in the transmitting / receiving coil L1 as a DC voltage by the power supply circuit 23. Therefore, the distance between the main body reader / writer 12 and the data carrier 10 is sufficiently close, so that a sufficient voltage can be induced as a power supply in the data carrier 10 and a transmission signal of sufficient strength can be transmitted. Thus, data communication between the two can be normally performed.

[0005]

However, the conventional data carrier 10 and the main body reader / writer 12
In the data communication between the two, there is a limit to the power that can be induced by the data carrier 10, and there is a problem that the communication distance cannot be increased due to the power consumption. Also, it is difficult to provide the data carrier 10 with various functions, for example, a display function and an input function, or there is a limit even if there is a case where the memory capacity in the data carrier 10 needs to be expanded.

On the other hand, by providing a power source such as a battery in the data carrier itself, the communication distance can be extended,
Alternatively, a solution for providing various functions such as a display function is also conceivable. However, if the data carrier is provided with a battery, it is necessary to replace the battery when the battery is exhausted, which is inconvenient for practical use. In addition, securing a storage space for the battery in a small data carrier becomes a problem. Alternatively, it is conceivable that the battery can not be replaced by being integrated into the data carrier, but there is a problem that the life of the data carrier is shortened, and it is difficult to mount the battery.

The present invention has been made in view of the above problems, and provides a data communication system using a data carrier capable of expanding and enhancing the functions of the data carrier while taking advantage of the characteristic of a data carrier that does not require a battery. That is its purpose.

[0008]

According to one aspect of the present invention, there is provided a data carrier having a non-volatile memory and operated by a voltage induced by a received signal, and a non-contact type data carrier. A data communication system having a main body reader / writer that performs data communication with the data carrier, wherein a relay reader / writer having a power supply and capable of reading or writing data in the non-volatile memory of the data carrier is provided in the data carrier more than the main body reader / writer. , So that data communication can be performed between the data carrier and the main body reader / writer via a relay reader / writer.

Since the data communication between the main body reader / writer and the data carrier can be performed via the relay reader / writer having the power supply, the communication distance can be made longer. Alternatively, a relay reader / writer having a power supply can be provided with a display function, an input function, and an extended memory function, so that the application range of the data carrier can be expanded. As the data carrier, for example, a non-volatile memory for storing data, a control unit for inputting / outputting data to / from the non-volatile memory, a command or data from the outside demodulated and sent to the control unit and read out from the non-volatile memory Transmitting and receiving means for modulating the output data and outputting the modulated data to the outside. Further, as the main body reader / writer, for example, a control unit connected to a computer that outputs a command or data to be transmitted to a data carrier, a command or data transmitted from the control unit is modulated, transmitted, and transmitted from the data carrier. And transmission / reception means for demodulating the received data. Further, as the relay reader / writer, for example, a computer means for outputting a command or data to be sent to a data carrier, and modulating and transmitting the command or data sent from the computer means and demodulating the data sent from the data carrier And transmission / reception means that perform the communication.

[0010] The relay reader / writer can be provided in a case for accommodating the data carrier so that it can be taken out.
Thereby, the relay reader / writer and the data carrier can be used integrally, or when the relay reader / writer is unnecessary, the relay reader / writer can be taken out of the case and used alone. Further, the relay reader / writer may be provided with switch means for turning off the power of the relay reader / writer when the data carrier is not accommodated in the case. This saves power consumption of the relay reader / writer when the relay reader / writer is not used. Furthermore, to the relay reader / writer,
A photo sensor for detecting the intensity of visible light may be provided, and switch means for turning off the power of the relay reader / writer when the light intensity detected by the photo sensor is smaller than a predetermined value may be provided. Thereby, when the relay reader / writer is not used, the power consumption of the relay reader / writer is saved.

[0011] The relay reader / writer may be provided with display means. Thereby, for example, the data content stored in the nonvolatile memory of the data carrier can be confirmed using the display means. Alternatively, the display means may display, when the data stored in the nonvolatile memory of the data carrier satisfies the search condition transmitted from the main body reader / writer, that fact. When the data carrier satisfies a predetermined search condition, the display means of the relay reader / writer corresponding to the data carrier displays the fact so that the data carrier satisfying the desired search condition can be quickly specified. Become. As the display means, for example, an LED, an LCD, or the like can be used.

Further, it is preferable that the main body reader / writer can directly read and write data in the nonvolatile memory of the data carrier. Since the main body reader / writer and the data carrier can directly communicate data without using the relay reader / writer, more various data carriers can be used.

Further, the relay reader / writer is provided with carrier sense means, and when the signal reception level of the signal from the main body reader / writer detected by the carrier sense means becomes equal to or higher than a predetermined level, the relay reader / writer transmits the data carrier. Access can be stopped. Thus, when the distance between the main body reader / writer and the data carrier is short and the relay reader / writer does not need to relay, the relay reader / writer automatically stops accessing the data carrier and the communication between the main body reader / writer and the data carrier. Data communication between them.

[0014]

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

(First Embodiment) FIG. 1 is a block diagram showing a first embodiment of the present invention. In the figure, 10 is a data carrier, 12 is a main body reader / writer for performing data communication with the data carrier 10 in a non-contact manner, and its basic configuration is the same as that shown in FIG. I do.

A relay reader / writer 14 is provided between the data carrier 10 and the main body reader / writer 12. The relay reader / writer 14 is the main body reader / writer 12
The data carrier 10 is disposed closer to the data carrier 10 than the data carrier 10 can read or write data, and can perform data communication between the data carrier 10 and the main body reader / writer 12 via the relay reader / writer 14. It has become.

More specifically, the relay reader / writer 1
4 is a card-shaped data carrier 1 as shown in FIG.
0 is provided integrally with a case 16 that removably accommodates it. FIG. 3 shows a block diagram of the relay reader / writer 14. In the figure, a relay reader / writer 14 includes a transmitting / receiving coil L4, a capacitor C4, amplifiers 43 and 44, a DPSK demodulator 45,
It has a DPSK modulator 46. For transmission and reception with the main body reader / writer 12, a transmission coil L5, a reception coil L6, capacitors C5 and C6, a resistor R, an amplifier 5
5, 56, a DPSK modulator 58, a DPSK demodulator 59,
CPU 60, frequency oscillator 61, numeric keypad 62 as input means, LCD 63 as display means, memory (EE
PROM) 64, battery 65 as power supply, switch 70
have. The switch 70 includes, for example, a mechanical sensor or a magnetic sensor and a contact. When the data carrier 10 is inserted into the case 16, the contact is turned on to supply the voltage of the battery 65 to the CPU 60 and the like. Can be used.

The relay reader / writer 14 of this example transmits / receives data to / from the data carrier 10 at a carrier frequency f1 (eg, 13.56 MHz) and receives a signal from the main body reader / writer 12 at a carrier frequency f2 (eg, 125 kHz). And the carrier frequency f2 / 2 (for example, 62.5 k
(Hz) to the main body reader / writer 12.

The operation of the relay reader / writer 14 is performed as follows. First, when the data carrier 10 is inserted into the case 16, the switch 70 is turned on and the battery 6 is turned on.
5 is connected to the CPU 60, and the CPU 60 starts operating. Then, by electromagnetic induction coupling between the transmission / reception coil L4 and the transmission / reception coil L1, data communication is performed with the data carrier 10 accommodated in the case 16, and the data in the memory 27 of the data carrier 10 is relayed via the CPU 60. The data is loaded into the memory 64 of the reader / writer 14. The content configuration of the memory 64 is exactly the same as the content configuration of the memory 27. When the loading is completed, the communication with the data carrier 10 ends, and the carrier signal of the frequency f1 stops.

Next, the CPU 60 is in a state of waiting for reception of a signal including a command from the main body reader / writer 12 at the frequency f2. When the relay reader / writer 14 detects the carrier signal of the frequency f2 from the main body reader / writer 12,
Demodulation is performed to read or write data on the data carrier 10 stored in the memory 64 depending on whether a command from the main body reader / writer 12 is a read command (read command) or a write command (write command). In the case of a read command, based on the designated address sent together with the read command, the data of the address of the corresponding memory 64 is read out, modulated by the modulator 58, and the frequency (１ ／) is transmitted from the transmission coil L5.
Transmission is performed using the carrier signal of f2. In the case of a write command, based on the specified address sent with the write command, the data sent with the write command is written to the corresponding address of the memory 64. After the writing is completed and the communication with the main body reader / writer 12 is completed, the communication with the data carrier 10 is performed again, and the address is changed to the address in the memory 27 of the data carrier 10 corresponding to the changed address. Write data.

Since the relay reader / writer 14 has the battery 65, normal communication can be performed even if the communication with the main body reader / writer 12 extends over a long distance.

Further, data can be directly written to the relay reader / writer 14 or data at a predetermined address can be read using the numeric keypad 62 and the LCD 63 provided on the relay reader / writer 14. The data written in the relay reader / writer 14 is transferred to the memory 27 of the data carrier 10 after the writing is completed.

In this way, it is possible to realize, via the relay reader / writer 14, a display function and an input function which are difficult to be realized by the data carrier 10 having no battery alone. The relay reader / writer 14 is different from the data carrier 10 in that
Because the space can be given a degree of freedom, the battery 6
5. The LCD 63 and the numeric keypad 62 can be provided relatively freely. Further, the replacement of the battery 65 can be performed relatively easily.

The main body reader / writer 12 operates at the frequency f2
In addition, by enabling transmission and reception to and from the data carrier 10 at the frequency f1, the data carrier 10 and the main body reader / writer 12 can be directly in data communication as in the related art. Therefore, for example, when the data carrier 10 and the main body reader / writer 12 are close to each other or when it is not necessary to attach a display function or a data input function to the data carrier 10, the data carrier 10 is detached from the case 16 and used. can do. An application example utilizing this feature is shown in FIG.

FIG. 7 shows a case where the main body reader / writer 12 is installed near the door D in order to manage entry / exit of a specific room.
It is connected to the. The main body reader / writer 12 reads out the ID data stored in the data carrier 10 held by the passerby, and the ID data is a specific ID for which entry into the room is permitted.
It is determined whether the number is a specific ID number, and if the ID number is a specific ID number, the locking device 18 is driven to unlock the door. Otherwise, the door is kept locked. As shown in FIG. 7A, when the passer-by causes the main body reader / writer 12 to read the ID data of the data carrier 10 owned by the passerby, the passerby places the data carrier 10 in the case 16.
And the case 16 is passed through the main body reader / writer 12 with the case 16 in a pocket or bag.
Data communication can be performed between the relay reader / writer 14 and the main body reader / writer 12 provided in the computer. Further, as shown in FIG. 7B, some passers-by remove the data carrier 10 from the case 16 and approach the main body reader / writer 12 so that the data carrier 10 is directly transferred between the main body reader / writer 12 and the data carrier 10. Can be read. In this way, the data carrier 10 can be used in a variety of ways.

(Second Embodiment) Next, FIG. 5 shows a second embodiment of the present invention.
1 shows an embodiment. Relay reader / writer 14 of this embodiment
-1 has transmission / reception coils L5 and L6, and the transmission / reception coil L6 has a data carrier 1 having a carrier frequency f2.
0 and both reception from the main body reader / writer 12 and transmission / reception coil L5
Both the reception from the data carrier 10 and the transmission to the main body reader / writer 12 are performed. Along with this,
A switch circuit 80 for switching between transmission and reception of the relay reader / writer 14 and a carrier sense circuit 94 for detecting the strength of a received carrier are provided.

As shown in FIG. 6, the switch circuit 80
A plurality of switches 82-1 to 82-8 switched by a switch control signal from the PU 60, capacitors C7 to C10, resistors R7 to R10, a driver 84,
It comprises a filter 86, amplifiers 88 and 89, an OR gate 90 and the like. At the time of data communication with the data carrier 10, the switches 82-1, 82-3, 82-5, 82-7
Are turned on, and during data communication with the main body reader / writer 12, the switches 82-2, 82-4, 82-6, 82-8
Becomes conductive. The switch control of the switch circuit 80 is performed, for example, from the start of signal transmission to the data carrier 10 to the lapse of a predetermined time period during which a reply from the data carrier 10 can be reliably obtained. 3, 82-5 and 82-7 are conducted,
Otherwise, the switches 82-2, 82-4, 82-6,
82-8 is conducted. Alternatively, a switch control signal may be generated by the CPU 60 at another timing or by switching a manual switch (not shown).

According to this embodiment, as in the first embodiment, even if the distance between the data carrier 10 and the main body reader / writer 12 is long, the relay reader / writer 14-
1 can be communicated. Further, the data carrier 10 and the main body reader / writer 12 are close to each other, and the transmission / reception coil L1 of the data carrier 10 and the transmission coil L2 and the reception coil L3 of the main body reader / writer 12 are at a distance sufficient to perform electromagnetic induction coupling. In some cases, the main body reader / writer 1 detected by the carrier sense circuit 94
2, the reception level of the carrier signal of frequency f2 is equal to or higher than a predetermined value. When the carrier sense circuit 94 detects that the level is equal to or higher than the predetermined level and outputs the signal to the CPU 60, the CPU 60 stops communication with the data carrier 10. This allows direct data communication between the main body reader / writer 12 and the data carrier 10 without interfering with the relay reader / writer 14-1. Also in this embodiment, the data carrier 10 is the case 1
6, it is possible to perform data communication directly with the main body reader / writer 12, and it can be used for the application as shown in FIG. Further, a plurality of relay reader / writers 14-1 may be interposed between the main body reader / writer 12 and the data carrier 10. FIG. 8 shows an application example. In this example, the relay reader / writer 14-
1 and another relay reader / writer 14-1 ′
It is used not as an integral part but as an auxiliary for the main body reader / writer 12. For example, a small auxiliary relay reader / writer 14-1 'for the main body reader / writer 12 is 1 m.
It is placed below the main body reader / writer 12 at a distance. Thus, when a short child or an elderly person passes, the data carrier 10 (or the relay reader / writer 14-1 provided in the case 16 accommodating the data carrier 10) carried by the short child or the elderly is passed. The auxiliary relay reader / writer 14-1 ′ is arranged closer than the main body reader / writer 12. Thus, the data carrier 10
(Or the relay reader / writer 14 provided in the case 16)
-1) passes closer by the auxiliary relay reader / writer 14-1 'than the main body reader / writer 12, the data is transmitted via the auxiliary relay reader / writer 14-1' and the relay reader / writer 14-1. Data communication between the carrier 10 and the main body reader / writer 12 is performed.

This auxiliary relay reader / writer 14-1 '
Can be added later independently of the main body reader / writer 12. At this time, since connection with the main body reader / writer 12 by a cable or the like is not necessary, interior installation work is unnecessary and installation can be easily performed. The auxiliary relay reader / writer 14-1 ′ has a power supply and can induce strong electromagnetic induction. Therefore, even if the coils are not opposed to the main body reader / writer 12, the auxiliary relay reader / writer Data communication can be performed.

(Third Embodiment) FIG. 9 is a block diagram showing a third embodiment of the present invention. The relay reader / writer 14-2 of this embodiment includes a receiving coil L5 and a transmitting / receiving coil L6.
And a carrier frequency f2 at the transmitting / receiving coil L6.
To the data carrier 10 and the main body reader / writer 1
2-1 for both transmission and reception, and the reception coil L
In step 5, reception is performed from the data carrier 10 having the carrier frequency f2 / 2. Accordingly, a switch circuit 100 for switching between transmission and reception of the relay reader / writer 14-2 is newly provided. Further, the main body reader / writer 12-1 of this embodiment
Has one transmission / reception coil L7 and additionally has a switch circuit 112 for switching between transmission and reception.

As shown in FIG.
Are a plurality of switches 102-1 to 102-switched by a switch control signal from the CPU 60.
4, capacitors C11 to C13, resistors R11 to R12,
Driver 104, filter 106, amplifiers 108 and 10
9, an OR gate 110 and the like. During data communication with the data carrier 10, the switches 102-1, 10
2-3 conducts. During data communication with the main body reader / writer 12-1, the switches 102-1 and 12-1 are transmitted at the time of transmission.
02-3 conducts, and switches 102-2, 102-2
2-4 conducts. The switch control of the switch circuit 100 is performed, for example, during the period from the start of signal transmission to the data carrier 10 to the lapse of a predetermined time period during which a reply from the data carrier 10 is reliably obtained, and at the time of transmission to the main body reader / writer 12-1. , Switches 102-1 and 102-
3 are turned on, and switches 102-2 and 102
-4 is conducted.

The switch circuit 112 of the main body reader / writer 12-1 includes a plurality of switches 1 as shown in FIG.
13-1, 113-2, 113-3, and 113-4 switch between transmission and reception.

In this embodiment, both the main body reader / writer 12-1 and the data carrier 10 have IDs respectively.
Have a number. Then, an ID number is always incorporated in a command at the time of communication and a response to this command, and communication is performed by identifying the main body reader / writer 12-1 and the data carrier 10. The main body reader / writer 12-1 or data carrier 10 having a different ID number does not respond to the relay reader / writer 14-2.

Thus, the main body reader / writer 12-1
Can be transmitted and received by one transmission / reception coil L7.

(Fourth Embodiment) Next, FIG. 11 shows a fourth embodiment of the present invention. The relay reader / writer 14-3 of this embodiment includes a receiving coil L5 and a transmitting / receiving coil L6.
And the carrier frequency f3 at the transmitting / receiving coil L6.
To the data carrier 10 and the main body reader / writer 1
2-1 for both transmission and reception, and the reception coil L
In step 5, transmission to the data carrier 10 at the carrier frequency 2f3 is performed. Also, a new switch switching signal generator 7
2, a switch 74 and a photo sensor 68,
Switch 70 including photo sensor 68 and magnetic sensor
Is sent to the switch switching signal generator 72. The switch 70 sends the signal to the switch switching signal generator 72 when the data carrier 10 is accommodated in the case 16, and
Numeral 8 is for sending a signal to the switch switching signal generator 72 when a predetermined amount of visible light is received. When receiving signals from both the photo sensor 68 and the switch 70, the switch switching signal generator 72 generates a switching signal, turns on the switch 74, and supplies the voltage of the battery 65 to the CPU 60. This reduces the current consumption of the battery 65 when the case 16 is in the dark, when the user is not active at midnight, and when the data carrier 10 is not housed in the case 16, and consumes the battery 65. Is preventing.

In this embodiment, the relay reader / writer 14-3 further includes the LEDs 120 and 121,
The relay reader / writer 14-3 and the data carrier 10 receive a search command from the main body reader / writer 12-1, and the LEDs 120 and 121 emit light when a search condition included in the search command is satisfied. Things. Figure 1 shows an application example using this search function.
It is shown in FIG.

FIG. 12 shows a relay reader / writer 14- integrated with a case 16 accommodating the data carrier 10.
3 shows an example where 3 is attached to a document file F. The data carrier 10 is stored in the memory 27 of the data carrier 10.
The file information such as the file name of the document file F to which the case 16 accommodating the document is attached and the document name in the file F are stored.

With reference to FIG. 13, an example of a search processing procedure in the main body reader / writer 12-1 and the relay reader / writer 14-3 when searching for a desired document file from a large number of document files F will be described. First, data carrier 1
When 0 is inserted into the case 16 and the photo sensor 68 detects external light, the switch 74 is turned on by the switch switching signal generator 72, and the voltage of the battery 65 is supplied to the CPU 60 of the relay reader / writer 14-3. . Then
The CPU 60 outputs a switch control signal to the switch circuit 100 'and waits for a signal from the main body reader / writer 12-1. The main body reader / writer 12-1
A signal is generated with the file data of the document file being searched together with the search command, and this signal is modulated at the carrier frequency f3 and transmitted (FIG. 13 (a)). This signal is transmitted and received by the transmission / reception coil L6 of the relay reader / writer 14-3.
Is input to the CPU 60 via the filter circuit and the amplifier included in the switch circuit 100 '. The relay reader / writer 14-3 immediately transfers the received search command and data to the data carrier 10 from the transmission coil L5 at the carrier frequency 2f3 with a delay of one element (1 bit) (FIG. 13B )). After the transfer, the CPU 60 of the relay reader / writer 14-3 temporarily stores the file data sent from the main body reader / writer 12-1 in a buffer register in the CPU 60 (FIG. 13D). On the other hand, the relay reader / writer 14-
When the signal transferred from 3 is received by the transmission / reception coil L1 of the data carrier 10, it is input to the control circuit 26 via the transmission / reception circuit 22 and the demodulator 24. When interpreting the search command, the control circuit 26 reads out the file data at a predetermined address in the memory 27 in which the file data is stored in advance, creates a response including the file data, and transmits the response through the modulator 25 and the transmission / reception circuit 22. A response is returned from the transmitting / receiving coil L1 at the carrier frequency f3 (FIG. 13C). When the response from the data carrier 10 is normally received, the relay reader / writer 14-3
Turns on the red LED 120 and externally displays that the search command has been received (FIG. 13E). Next, it is compared whether or not the file data temporarily stored in the buffer memory matches the data sent from the data carrier 10 (FIG. 13D).
The ED 120 is changed to a blue LED 121, and the fact that the search data has been found is displayed externally (FIG. 13E). At this time, the relay reader / writer 14-3
No response is returned to 2-1 (FIG. 13 (f)).

As described above, by turning on the LED 121 which is a display means provided in the relay reader / writer 14-3, it is possible to confirm that the data carrier 10 matches the search condition output from the main body reader / writer 12-1. Since it is displayed, the searcher can immediately find the desired document file F. Further, the main body reader / writer 12-1 can search from a distance (30 cm or more) away from the document file F, and find a desired document file F from the document file F to which a large number of data carriers 10 are attached at one time. be able to. FIG. 14 is a timing chart illustrating a processing procedure when a read command or a write command other than the search command is transmitted from the main body reader / writer 12-1 to the data carrier 10. When a command is sent from the main body reader / writer 12-1 at the carrier frequency f3 (FIG. 14A), the relay reader / writer 14-3
Then, the command is transferred to the data carrier 10 at the carrier frequency 2f3 with a delay of one element (one bit), and a response from the data carrier 10 is waited (FIG. 1).
4 (b)). When reading or writing of data in the memory 27 is completed in response to a command in the data carrier 10 and a response is output at the carrier frequency f3.
(FIG. 14C), the relay reader / writer 14-3 temporarily stores the response (FIG. 14E), and then transfers the response to the main body reader / writer 12-1 at the carrier frequency f3 (FIG. 14E). FIG. 14D). In this example, since the transmission frequency from the data carrier 10 and the transmission frequency to the main body reader / writer 12-1 are the same, the relay reader / writer 14-3 temporarily responds to the data carrier 10 so as not to overlap. I remember. The transmission data from the main body reader / writer 12-1 is transferred to the relay reader / writer 14-.
3 is received, all bits are temporarily transferred to the relay reader / writer 1
After storing the data in 4-3, the data may be transmitted to the data carrier 10, and the communication frequency with the data carrier 10 may be set to a frequency f4 higher than f3, and high-speed bit rate communication transfer may be performed.

In the above-described embodiment, the card-like data carrier is taken as an example. However, the present invention is not limited to this, and it goes without saying that a tag-like data carrier is also applicable. is there.

[0041]

As described above, according to the present invention,
Since data communication between the main body reader / writer and the data carrier can be performed via a relay reader / writer having a power supply, the communication distance can be made longer, and the applicable range of the data carrier can be expanded. Become like Therefore, there is no need to provide a battery in the data carrier.

Further, a relay reader / writer having a power supply can be provided with, for example, a display function and an input function, so that the applicable range of the data carrier can be expanded.

[Brief description of the drawings]

FIG. 1 is an overall block diagram showing a data communication system of the present invention.

FIG. 2 is a perspective view illustrating an example of a relay reader / writer integrally provided in a case of the present invention.

FIG. 3 is a block diagram of a relay reader / writer, a reader main unit, and a data carrier according to the first embodiment of the present invention.

FIG. 4 is a block diagram of a conventional data communication system including a main body reader / writer and a data carrier.

FIG. 5 is a block diagram of a relay reader / writer, a reader main unit, and a data carrier according to a second embodiment of the present invention.

FIG. 6 is a circuit diagram of a switch circuit of the relay reader / writer in FIG. 5;

FIGS. 7A and 7B are explanatory diagrams showing an application example of a data communication system using a relay reader / writer.

FIG. 8 is an explanatory diagram showing an application example of a data communication system using a relay reader / writer.

FIG. 9 is a block diagram of a relay reader / writer, a reader main unit, and a data carrier according to a third embodiment of the present invention.

FIG. 10 is a circuit diagram of a switch circuit of the relay reader / writer of FIG. 9;

FIG. 11 is a block diagram of a relay reader / writer, a reader main unit, and a data carrier according to a fourth embodiment of the present invention.

FIG. 12 is an explanatory diagram showing an application example using a search function of a data communication system using a relay reader / writer.

FIG. 13 is a timing chart illustrating a search processing procedure in the data communication system of the present invention.

FIG. 14 is an example of a timing chart illustrating a normal processing procedure other than a search in the data communication system of the present invention.

[Explanation of symbols]

Reference Signs List 10 Data carrier 27 Non-volatile memory 12, 12-1 Main body reader / writer 14, 14-1, 14-1 ', 14-2, 14-3 Relay reader / writer 16 Case 63 LCD (display means) 65 Battery (power supply) 68 Photosensor 70 Switch 74 Switch 94 Carrier sense circuit 121 LED (display means)

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5B058 CA17 5K012 AA01 AA03 AB05 AB18 AC06 AC08 AC09 AC10 AC11 AC12 AE13 BA02 BA07

Claims (8)

[Claims] 1. A data communication system comprising: a data carrier having a non-volatile memory and operated by a voltage induced by a received signal; and a main body reader / writer for performing data communication with the data carrier in a non-contact manner. A relay reader / writer capable of reading or writing data in the nonvolatile memory of the data carrier is arranged closer to the data carrier than the main body reader / writer, and the data carrier and the main body reader / writer are connected via the relay reader / writer. A data communication system that enables data communication with the device. 2. The relay reader / writer according to claim 1, wherein the relay reader / writer is provided in a case accommodating the data carrier so that the data carrier can be taken out.
A data communication system as described. 3. The relay reader / writer has a switch unit for turning off the power of the relay reader / writer when the data carrier is not accommodated in the case.
A data communication system as described. 4. The relay reader / writer further includes a photo sensor for detecting the intensity of visible light, and when the light intensity detected by the photo sensor is smaller than a predetermined value, the power of the relay reader / writer is turned off. 4. The data communication system according to claim 2, further comprising switch means for switching. 5. The data communication system according to claim 1, wherein said relay reader / writer has a display unit. 6. The data according to claim 5, wherein said display means displays, when data stored in a nonvolatile memory of said data carrier satisfies a search condition transmitted from said main body reader / writer. Communications system. 7. The data communication system according to claim 1, wherein said main body reader / writer can directly read and write data in said nonvolatile memory of a data carrier. 8. The relay reader / writer includes a carrier sensing unit, and when a reception level of a signal from the main body reader / writer detected by the carrier sensing unit becomes equal to or higher than a predetermined level, the relay reader / writer is activated. The data communication system according to claim 7, wherein access to the data carrier is stopped.