JP2002083277A - Data carrier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a data carrier, capable of solving the problem that conventionally there is a possibility of disconnection between an antenna and an IC or malfunctions of the IC to lower reliability of the data carrier, because one antenna and one IC are mounted to a label-shaped or card-shaped base material having a comparatively thin and flexible structure, in the data carrier. SOLUTION: At least two ICs 3, 4 are integrated in the data carrier, and the ICs are connected to the antenna 1. By integrating two ICs 3, 4 in the data carrier, if one IC becomes faulty, or even if there is a fault with its connection to the antenna, the other will work as a back-up.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data carrier (RF-ID tag, RF-ID tag, etc.) for returning a response signal to an inquiry signal from an interrogator using electromagnetic waves or light as a communication medium and storing data sent from the interrogator. In particular, the present invention relates to a data carrier which improves the reliability of stored data and can easily cope with a shortage of memory.

[0002]

2. Description of the Related Art In recent years, a data carrier system composed of an interrogator and a data carrier has been actively researched and developed, and has been put to practical use in various fields. Of these, as a data carrier serving as a data storage medium, a base material having a relatively thin and flexible structure such as a label or card shape is often used.

An antenna such as a dipole antenna or a loop is embedded in the label or card-shaped data carrier.
C (semiconductor integrated circuit) is embedded. This IC is
Using an electromagnetic wave or light as a communication medium, it operates to return the stored data in response to the interrogation signal from the interrogator and to write the data sent from the interrogator.

Since the interrogator and the data carrier are not in contact with each other, a power source for driving an IC in the data carrier uses energy of a communication medium transmitted from the interrogator after converting it into electric power, or uses an IC. The battery buried together is used.

FIG. 10 is a diagram showing an example of the configuration of a conventional data carrier. A data carrier (RF-ID) for communicating data with an interrogator in a non-contact manner using electromagnetic waves as a communication medium.
Tag). In FIG. 10, capacitors 10 constituting a resonance circuit are provided at both ends of a coiled antenna 101.
2 are connected, and IC 1 is connected to both ends of the antenna 101.
The terminal a of No. 03 is connected to a terminal Vss (ground terminal), and power is supplied to the IC 103 by electromagnetic induction by a high-frequency electromagnetic field transmitted from the interrogator. The intermediate terminal m of the coil-shaped antenna 101 is the terminal b of the IC 103.
It is connected to the. And the internal circuit of the IC 103 is
Turn on / off the FET (field effect transistor) / Tr connected between the terminal b and the terminal Vss, and
It is configured to change the inductance of the coil 01 and return a response signal to the interrogator.

As shown in this example, in a conventional data carrier, one antenna 101 and one IC 103 are embedded in a label or card-shaped base material.

[0007]

As described in the section of the prior art, a data carrier often uses a base material having a relatively thin and flexible structure such as a label or a card, and one antenna is included in the base material. And one IC was mounted.

For this reason, when an external force or impact is applied to the data carrier, the data carrier is easily deformed, and the line connecting the antenna 101 and the IC 103 is disconnected,
In some cases, a failure such as breakage of the C103 itself occurred. Once a failure occurs, the data carrier is no longer usable and needs to be replaced.

However, regarding the exchange of the data carrier, for example, when the data carrier is used for managing piping embedded in the wall of a building and the data carrier itself is embedded in the wall, It becomes a troublesome problem. In other words, when replacing a failed data carrier, crushing the part of the wall where the data carrier is embedded, then replacing the data carrier, and then repairing the wall, etc. This is because it requires expense.

Also, depending on the required specifications of the application, the memory capacity of the IC used for the data carrier may be insufficient. In such a case, it is sufficient to design an IC with a newly increased memory capacity. However, designing a new IC is enormously expensive and time-consuming, cannot be easily executed, and makes good use of existing ICs. There has been a demand for the development of a data carrier that solves the problem of insufficient memory.

In view of the above problems, a first object of the present invention is to significantly improve the reliability of a data carrier having a relatively flexible structure of a label or a card and to provide a data carrier in a place where repair and replacement are difficult. It is also to provide a usable data carrier.

A second object of the present invention is to provide a new IC
An object of the present invention is to provide a data carrier capable of solving a memory shortage problem by effectively utilizing an existing IC without developing the IC.

[0013]

According to a first aspect of the present invention, there is provided a data carrier for transmitting storage data designated by a read command from an interrogator and writing data from the interrogator. The data carrier storing the data transmitted from the interrogator according to the present invention is characterized in that at least two ICs for executing a write command and a read command from the interrogator are incorporated.

According to a second aspect of the present invention, the data carrier transmits, using electromagnetic waves as a communication medium, storage data designated by a read command from the interrogator, and data transmitted from the interrogator by a write command from the interrogator. In the data carrier to be stored, at least two ICs for executing a write command and a read command from an interrogator are incorporated, and the plurality of ICs are connected to one common antenna.

According to a third aspect of the present invention, the data carrier transmits, using electromagnetic waves as a communication medium, storage data designated by a read command from the interrogator, and data transmitted from the interrogator by a write command from the interrogator. In the data carrier to be stored, a plurality of antennas are built in, and a plurality of ICs for executing a write command and a read command from an interrogator are built in. Each antenna has
At least one of the ICs is connected.

According to a fourth aspect of the present invention, there is provided a data carrier according to the third aspect, wherein the plurality of antennas are arranged at or near a position where their mutual interference is minimized.

According to a fifth aspect of the present invention, in the data carrier according to any one of the first to fourth aspects, a data storage area of each of the plurality of ICs includes:
A data area for writing ID information for identifying each mounted IC is provided, and data is written and read in accordance with a command from an interrogator using the ID information as an index.

According to a sixth aspect of the present invention, in the data carrier according to any one of the first to fifth aspects, a data storage area of each of the plurality of ICs includes:
A data area is provided for writing ID information for identifying a tag on which those ICs are mounted and ID information for identifying each of the mounted ICs. Using these ID information as indices, data is written and written according to a command from an interrogator. Reading is performed.

A data carrier according to claim 7 is the data carrier according to any one of claims 1 to 6, wherein each of the plurality of ICs has a data storage area,
A data area is provided for writing information on a data configuration order used when a plurality of ICs share and store data, and data is written and read in response to a command from an interrogator using the information on the data configuration order as an index. Is performed.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] FIG. 1 is a diagram showing a circuit configuration of a first embodiment of the present invention.
FIG. 3 is a diagram showing an actual connection state according to the first embodiment of the present invention. This is an example in which one antenna coil and two ICs are mounted on a label-shaped or card-shaped base material.

In FIGS. 1 and 2, reference numeral 1 denotes a coiled antenna, 2 denotes a capacitor forming a resonance circuit with the antenna 1, and 3 and 4 denote ICs. The symbol Tr in the ICs 3 and 4 indicates a switching FET.

In this example, the antenna 1 has a coil shape formed by a pattern of a printed circuit board, and has an outer shape 50.
mm and 5 turns. Its inductance is about 3 μH, and a 46 pF chip capacitor 2 is connected in parallel with the coil forming the antenna 1 so as to resonate at 13.56 MHz. Two ICs 3 and 4 are connected in parallel to this coil to form a data carrier (hereinafter, this data carrier is simply referred to as a “tag”).

That is, both ends of the coil of the antenna 1 and I
The a terminal of C3, 4 and the Vss terminal (ground terminal) are connected, an intermediate tap m is taken out from the position of the first turn from the Vss terminal side of the coil of the antenna 1, and this is connected to the IC
Connect to terminals 3 and 4. The copper foil at the connection part of the antenna is subjected to strike plating of gold having a thickness of 1 nm to have a diameter of 25 mm.
After connecting with an aluminum wire of nm, the resultant was sealed by resin potting.

Next, the operation of this tag will be described.
When the tag is placed in a 13.56 MHz magnetic field, the antenna 1
A voltage is induced in the resonance circuit composed of the coil and the capacitor 2, and this voltage is applied between the terminals a and Vss of the ICs 3 and 4. When this voltage exceeds a certain value, IC
The internal circuits 3 and 4 start operating. When the internal circuits of the ICs 3 and 4 start operating, the ICs 3 and 4 transmit data corresponding to the contents of the internal memory (capacity 160 bits) to the interrogator as a Manchester code at a data rate of 80 kbs. FIG. 3 shows an example of the Manchester code.

After the transmission, a standby state of about 80 to 120 msec is reached, and the operation of transmitting the data again is repeated as long as power is supplied. Specifically, data transmission is performed by an FET Tr having a drain and a source connected between the b terminal and the Vss terminal inside the ICs 3 and 4, respectively.
This is performed by applying ON and OFF voltages to the gate terminal.

Since the coil serving as the transmitting antenna of the interrogator and the coil serving as the antenna 1 of the tag are magnetically coupled, the FETs / Tr of the ICs 3 and 4 in the tag are turned ON and OFF.
By performing FF, the inductance of the antenna 1 on the tag side changes, and the change in the inductance is extracted as a change in impedance as viewed from the antenna side of the interrogator, and the tag data is read.

Next, two ICs each having two built-in ICs
A case where data is read from two tags (tag A and tag B) will be described. In this example, tag A contains
IC # 1 and IC # 2 are built in.
This is an example in which C # 3 and IC # 4 are built in and two tags enter the electromagnetic field of the interrogator at the same time.

FIG. 4 is a diagram showing an example 1 of a configuration of memory data in an IC, and shows an example of a configuration of data in a data storage area in the IC. Memory address 0
7 bits are a data header, and all ICs (IC
“FF” is commonly written for # 1 to IC # 4). The 8 to 39 bits of the memory address are a unique chip ID (identification code) for each IC,
This makes it possible to identify that the data is from different ICs. Bits 40 to 47 of the memory address are the ID of the tag
(Identification code), and it is possible to identify which tag the data is transmitted from the IC embedded. Bits 48 to 159 of the memory address are an arbitrary data area used according to the application.

FIG. 5 is a diagram showing the data transmission timing. Each IC (IC # 1, IC # 2, IC # 3, IC #
It is the figure which showed the timing which the data from 4) transmitted. Actually, a packet having a width of about 2 msec is about 8
Although the data is transmitted at an interval of 0 to 120 msec, FIG. 5 shows the data transmission interval shorter than the actual time scale in order to make the drawing easier to see.

That is, when two tags A and B enter the magnetic field of the interrogator at the same time, each IC (IC # 1, I # 1)
C # 2, IC # 3, IC # 4) are simultaneously turned on,
Since each IC transmits data packets at the same time, the first packets all collide and cannot be successfully received by the interrogator. However, since the waiting time until the next packet transmission differs depending on each IC, it is possible to receive data from all ICs after a certain time has elapsed.

Also, the computer placed inside the interrogator can compare the chip ID of the received data packet and the ID of the tag, and arrange the data from the same tag in the order of writing.

Here, by writing exactly the same data in an arbitrary data area in the IC shown in FIG. 4, even if a failure occurs in the function of one IC or the connection with the antenna, the other IC is used. Thus, the interrogator can receive data.

The interrogator has the same tag ID and the chip I
If D receives different data, it can be seen that multiple ICs are operating in the same tag. When writing exactly the same data to the IC, it is not necessary to identify each IC, and therefore, it is possible to use an IC that does not have a unique chip ID.

Also, different values are written in the "arbitrary data" portion, and the data writing order according to the size of the IC chip ID is defined in advance, so that after reading, the same tag ID is used as an index. It is possible to reproduce the order in which the data was written by identifying whether the data is from the same tag or not, and rearranging the data based on the chip ID of the IC for the data determined to be from the same tag. By this operation, an effect similar to that of increasing the memory capacity can be obtained in principle.

It is not easy to manage the chip ID of each IC, write data in that order, and mount the data on the tag in terms of manufacturing process management. In such a case, for example, FIG. As shown in FIG. 2 showing a configuration example 2 of memory data in an IC, information indicating the order of data is written in two bits of memory addresses 40 and 41, thereby managing the order of up to four ICs. be able to. In this case, since a chip ID for identifying the order of data is unnecessary, an IC having no chip ID can be used, which is advantageous in manufacturing management.

If it is desired to further improve the reliability of data reading, a third example of the data structure in the IC shown in FIG.
As shown in (1), by setting the address 42 and 43 bits as an information area of the number of ICs included in the tag, errors such as skipping of data can be prevented. This method can also be applied to the case of the first configuration example of the memory data shown in FIG.

As described above, various combinations of the above-described configuration examples of the memory data, for example, a configuration in which a tag containing a plurality of ICs incorporates four ICs, two of which have the same data. For example, various combinations can be selected according to the application.

[Second Embodiment] In the first embodiment, a case where one coil-shaped antenna 1 is built in one tag and two ICs 3 and 4 are connected to this is described. However, as shown in FIG. 8 showing the second embodiment of the present invention, two coils 1
It is also possible to include a built-in resonance circuit composed of the capacitors 1 and 21 and the capacitors 12 and 22, and to connect one or more ICs to the resonance circuit. In the example of FIG.
In this example, two ICs 13 and 14 are connected, and two ICs 23 and 24 are connected to the antenna 21.

In this case, the arrangement of the coils is basically arbitrary. In particular, if the coils of the two antennas are arranged such that the coupling coefficient between the coils can be regarded as substantially zero, the independence increases. As a specific example, FIG. 9 is a diagram illustrating an example of the arrangement of the antennas. The ratio of the area S2 of the overlapping portion of the two antennas 31 and 32 to the area S1 of the non-overlapping portion is S1: S2 = 2. : 1 to 8: 1 gives good results.

In the case where a plurality of antennas are provided and arranged independently as described above, there are advantages described below.

In general, when an interrogator writes data to an IC, the transmitted high frequency is, for example, amplitude-modulated to superimpose a signal on a high frequency serving as an energy source for driving the IC and transmit the signal. However, in the configuration of the first embodiment, since each IC shares an antenna, while one IC is transmitting data, the other IC receives a signal from the interrogator. It is not possible. For this reason,
Writing data from the interrogator to the IC must be performed on both ICs.
It cannot be executed until after the data transmission is completed.

On the other hand, when two antennas are arranged in the tag such that the magnetic coupling coefficient becomes substantially 0 as in the second embodiment, the connection to one of the antennas is made. Since the IC connected to the other antenna can read the information from the interrogator while the transmitted IC is transmitting data, the interrogator can write data to the tag at any time.

Further, for example, an IC such as MCRF355 sold by Microchip Technology, USA
In C, the FET Tr shown in FIG. 1 is turned on during the standby time after transmitting the data packet (the cloaking function is described in the catalog), so the first embodiment is performed. In the configuration described above, the other IC cannot obtain energy, and a plurality of ICs cannot be mounted as in the present invention. When such a commercially available IC is used, a data carrier incorporating a plurality of ICs is configured by using a plurality of antennas having a coupling coefficient of substantially 0 as in the second embodiment. Can be.

Although the configuration of the memory data in the IC has not been described in the second embodiment, it is needless to say that the same configuration as in the first embodiment can be adopted.

Lastly, in the above-described first and second embodiments, the resonance circuit is constituted by an external capacitor. However, the resonance circuit may be constituted by using a capacitor built in an IC. It is possible.

In the first and second embodiments described above, an example is described in which a passive type IC having no power supply is used.
The same can be applied to a tag that supplies the power from the built-in battery.

Further, in the first and second embodiments described above, when the power of the IC is turned on, the IC
Described an example of using a so-called tag talk first type IC which automatically starts transmitting data. However, an interrogator first transmits a polling signal, and the IC responds only after receiving a polling signal. The present invention can be similarly applied to a case where a leader talk first IC is used.

[0048]

According to the data carrier according to the first and second aspects of the present invention, at least two data carrier ICs are built in one data carrier, so that the function of one IC fails. Even in the case where the connection to the antenna becomes defective, the data carrier itself does not need to be replaced because at least two other built-in ICs function as backups. Further, when particularly high data reliability is required, three or more ICs are built in, and data reliability can be improved by majority decision.

According to the data carrier of the third and fourth aspects, since a plurality of antennas are used, even if the function of one of the antennas and the IC fails, the other antenna and the IC can back up the data. Reliability is improved. In addition, even when an IC connected to one antenna is transmitting data to the interrogator, the IC connected to the other antenna can read information from the interrogator independently. Can write data to the data carrier.

According to the data carrier of the fifth, sixth and seventh aspects, when the memory capacity of the IC in the data carrier is insufficient for the required specifications of the application, each IC in the data carrier can be used. By using the tag ID, the chip ID of each IC, or the information of the data configuration order of each IC written in the data storage area as an index, the software of the interrogator actually writes data to a plurality of ICs / from a plurality of ICs. Can be regarded as substantially a data write / read operation for one IC, so that it is not necessary to develop a new IC having a large memory capacity.

[Brief description of the drawings]

FIG. 1 is a diagram showing a circuit configuration according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating an actual connection state according to the first embodiment of this invention.

FIG. 3 is a diagram illustrating an example of a Manchester code.

FIG. 4 is a diagram showing a configuration example 1 of memory data in an IC.

FIG. 5 is a diagram showing transmission timing of data.

FIG. 6 is a diagram illustrating a configuration example 2 of memory data in an IC.

FIG. 7 is a diagram showing a configuration example 3 of memory data in an IC.

FIG. 8 is a diagram showing a second embodiment of the present invention.

FIG. 9 is a diagram showing an example of an antenna arrangement.

FIG. 10 is a diagram showing a configuration example of a conventional data carrier.

[Explanation of symbols]

 1, 11, 21, 31, 32 Antenna 2, 12, 22 Capacitor 3, 4, 13, 14, 23, 24 IC

Claims (7)

[Claims] 1. A data carrier for transmitting storage data designated by a read command from an interrogator and storing data transmitted from the interrogator by a write command from the interrogator, comprising: A data carrier comprising at least two ICs for executing a read command. 2. A data carrier for transmitting storage data specified by a read command from an interrogator using an electromagnetic wave as a communication medium and storing data transmitted from the interrogator by a write command from the interrogator. A data carrier including at least two ICs for executing a write command and a read command from a device, and connecting the plurality of ICs to one common antenna. 3. A data carrier for transmitting, using electromagnetic waves as a communication medium, storage data designated by a read command from an interrogator and storing data transmitted from the interrogator by a write command from the interrogator. And a plurality of ICs for executing a write command and a read command from an interrogator, and at least one of the ICs is connected to each antenna. 4. The data carrier according to claim 3, wherein the plurality of antennas are arranged at or near a position where their mutual interference is minimized. 5. A data area in which ID information for identifying each mounted IC is provided in a data storage area of each of the plurality of ICs. The data carrier according to claim 1, wherein writing and reading are performed. 6. The data storage area of each of the plurality of ICs includes an ID for identifying a tag on which the IC is mounted.
2. A data area in which D information and ID information for identifying each mounted IC are provided, and data writing and reading are performed in response to a command from an interrogator using the ID information as an index. 6. The data carrier according to any one of claims 1 to 5. 7. A data area for writing information on a data configuration order used when a plurality of ICs share data to store data is provided in each data storage area of the plurality of ICs. The data carrier according to any one of claims 1 to 6, wherein writing and reading of data are performed according to a command from an interrogator, using the information of (1) as an index.