JP2000174539A - Antenna system and card-shaped storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an antenna system capable of receiving electromagnetic waves with the best reception efficiency by providing plural resonating means set to respectively different resonance frequencies. SOLUTION: Concerning a duplication correspondent type IC card, a first resonance circuit 37 is constituted by connecting a resonance capacitor 31 to a loop antenna 32 loaded on a substrate 15, and a second resonance circuit 38 is constituted by connecting a resonance capacitor 34 to a loop antenna 33. The resonance circuits 37 and 38 are connected through a capacitor 35 and even when the distance of antennas 32 and 33 is extended, received power can be supplied to an electronic circuit 36. The first resonance circuit 37 is set to the resonance frequency coincident with the carrier frequency of electromagnetic waves radiated from a data writer/reader. The second resonance circuit 38 is set to the higher resonance frequency previously estimating a component to be lowered when two IC cards are overlapped.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antenna device and a card-shaped storage medium, for example, an IC (Integrated Circuit).
t) The present invention is suitably applied to an antenna device and a card-shaped storage medium for writing and reading data without contact with a card.

[0002]

2. Description of the Related Art In recent years, an IC card system using a data writer / reader and an IC card has been experimentally introduced in the fields of ticket gates, security systems, electronic money systems, and the like in stations. Writing of data to and reading of data from an IC card is performed in a non-contact manner.

As shown in FIG. 8, an IC card system 1
Is composed of a data writing / reading device 2 and an IC card 5 which are arranged so as to face each other. The electromagnetic wave radiated from the loop antenna 4 of the data writing / reading device 3 is
The magnetic field is received by the loop antenna 6 of the resonance circuit 8 provided in the IC card 5 and flows as a resonance current through the resonance capacitor 7 to generate a magnetic field, and the received power corresponding to the energy of the magnetic field is supplied to the electronic circuit 9. It is made to operate.

In the IC card 5 in this case, the resonance frequency F _res of the resonance circuit 8 matches the carrier frequency F _{car of the} electromagnetic wave radiated from the loop antenna 4 of the data writing / reading device 3 as shown in FIG. This improves the electromagnetic wave reception efficiency.

In the IC card system 1, a predetermined logical protocol is incorporated, whereby a plurality of IC cards 5 are simultaneously placed on the loop antenna 4 of the data writing / reading device 3 in a state of being overlapped. In this case, data transmitted and received for each IC card can be surely processed without collision.

However, as shown in FIG. 10, when a plurality (N) of IC cards 5A to 5N are arranged in a state of being superposed on the loop antenna 4 of the data writing / reading device 3, the capacitance of the resonance capacitor is increased. _Cres becomes N times and the load resistance R _cir of the electronic circuit 9 becomes 1 / N times.

As described above, a plurality (N) of IC cards 5A
５5N are superposed, the capacitance C of the resonance capacitor is
_{As res} becomes N times, the resonance frequency F _res becomes √
(1 / N).

Therefore, as shown in FIG.
In the state where A to 5N are simultaneously superimposed, the resonance frequency F _res by the resonance circuit 8 becomes the carrier frequency F of the electromagnetic wave radiated from the loop antenna 4 of the data writing / reading device 3.
_A large deviation from _car causes a significant decrease in reception efficiency and makes communication difficult.

Therefore, as a conventional method, as shown in FIG. 12, the resonance frequency F _res of the IC card 5 does not match the carrier frequency F _car ,
It is common practice to set a little higher in advance than the _car . When two or three such IC cards 5 are stacked, the reduced resonance frequencies F _res ′ and F _res ″
And the carrier frequency F _car is minimized, and it is possible to transmit and receive data at a certain communication distance even when one or a plurality of sheets are stacked while preventing a significant decrease in reception efficiency.

[0010]

By the way, in the IC card 5 having such a configuration, the resonance frequency _Fres is set slightly higher than the carrier frequency F _{car in} advance, so that only one IC card 5 writes data. When the reader 3 is disposed so as to face the loop antenna 4, the resonance frequency F _res and the carrier frequency F _car cannot be completely tuned.

For this reason, in the IC card 5, not only the communication distance of one card is sacrificed, but also the reception efficiency cannot be improved even when a plurality of cards are stacked. There is a problem that it is desired to further improve the reception efficiency even when sheets are stacked.

The present invention has been made in view of the above points, and has as its object to propose an antenna device and a card-shaped storage medium which can always receive electromagnetic waves with the best reception efficiency.

[0013]

According to the present invention, there is provided an antenna apparatus for receiving an electromagnetic wave via a resonance means, wherein a plurality of resonance frequencies set to different resonance frequencies higher than a carrier frequency of the electromagnetic wave are provided. Means for tuning the resonance frequency lowered by one of the plurality of resonance means and the other antenna apparatus to the carrier frequency of the electromagnetic wave when the antenna apparatus and another antenna apparatus come close to each other. Electromagnetic waves can always be received with the best reception efficiency even when approaching.

According to the present invention, in a card-shaped storage medium for writing and reading data to and from a predetermined electronic circuit in a non-contact manner via an electromagnetic wave, a plurality of resonance frequencies set to different resonance frequencies higher than the carrier frequency of the electromagnetic wave. When writing and reading data to and from an electronic circuit in a state in which the card-shaped storage medium and another card-shaped storage medium are close to each other, one of the plurality of resonance means and another card-shaped storage medium are provided. By tuning the lowered resonance frequency to the carrier frequency of the electromagnetic wave, the electromagnetic wave can always be received with the best reception efficiency even when a plurality of card-shaped storage media approach each other.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

(1) Overall Configuration of IC Card System In FIG. 1, reference numeral 10 denotes a non-contact type IC (Integ
rated circuit), which comprises an IC card 11 as a card-shaped storage medium and a data writing / reading device 21 arranged so as to face each other.

The IC card 11 is a batteryless IC card having no battery for power supply. The IC card 11 is mounted on, for example, a credit-card-shaped flat board 15 and radiated from the data writing / reading device 21. A coiled loop antenna 12 that receives an electromagnetic wave (shown by a broken line) and converts it into an electric signal, a modulation / demodulation circuit 13 that modulates transmission data or demodulates reception data, and analyzes received data and generates transmission data. And a signal processing circuit 14.

In practice, in the IC card 11, the electromagnetic wave radiated from the data writing / reading device 21 is received by the loop antenna 12, and is transmitted to the modulation / demodulation circuit 13 as a modulated wave. The modulation / demodulation circuit 13 demodulates the modulated wave, and outputs the demodulated wave to the reproduction data D1 sent from the data writing / reading device 21.
To the signal processing circuit 14.

The signal processing circuit 14 has a CPU (Central
ssing Unit) and read only memory (ROM) or RA
M (Random Access Memory) inside (not shown),
The program stored in the ROM is read out, the reproduction data D1 is analyzed on the RAM, and the response data D2 stored in the internal nonvolatile memory (not shown) is read out based on the reproduction data D1, and this is modulated and demodulated. Send it to the circuit 13. The modulation / demodulation circuit 13 modulates based on the response data D2 and radiates it from the loop antenna 12 to the data writing / reading device 21 as an electromagnetic wave.

Here, the modulation / demodulation circuit 13 has a power supply circuit (not shown) for converting the magnetic field energy of the electromagnetic wave into a stable DC power supply therein. The power supply circuit converts the received electromagnetic wave into a DC power supply DC1 based on the received electromagnetic wave and supplies the DC power supply to the signal processing circuit 14, and sends out the clock signal CLK1 generated based on the received electromagnetic wave to the signal processing circuit 14, and performs various control operations. Is received from the signal processing circuit 14.

The data writing / reading device 21 sends an instruction signal S1 from an input unit 26 comprising a keyboard, an operation panel and the like to a signal processing unit 24. The signal processing unit 24 includes a CPU, and has a ROM and a RAM therein (not shown).
Is read out, and an instruction signal S1
The transmission data D3 to be transmitted to the IC card 11 is generated by performing signal processing according to the above on the RAM, and this is transmitted to the modulation / demodulation circuit 23.

The modulation / demodulation circuit 23 transmits the transmission data D3 using a carrier in a predetermined frequency band that can be radiated efficiently.
And radiates it from the loop antenna 22 as an electromagnetic wave.

The data writing / reading device 21 receives the electromagnetic wave radiated from the IC card 11 by the loop antenna 22 and sends it to the modulation / demodulation circuit 23 as a modulation wave. The modulation / demodulation circuit 23 demodulates the modulated wave and outputs
The data is transmitted to the signal processing unit 24 as the reproduction data D4 transmitted from the card 11.

Here, the signal processing section 24 converts the DC power supply DC2 supplied from the power supply circuit (not shown) into a modulation / demodulation circuit 23.
, And a clock signal CLK2 and a control signal CTL2 for various controls are sent to the modulation / demodulation circuit 23.

The signal processing section 24 performs signal processing based on the received reproduction data D4, and displays the result on a display 25. Further, the signal processing unit 24 can send a signal processing result based on the reproduction data D4 to the external device 27.

(2) IC Card Compatible with Plural Stacks Next, the electromagnetic wave radiated from the data writing / reading device 21 is received by the loop antenna 12 with the best reception efficiency even when the plural cards are stacked. A specific configuration of the IC card 11 of the above-described type that can handle a plurality of stacked cards will be described.

(2-1) IC Card Compatible with Two-Layer Stack As shown in FIG.
It has a first resonance circuit 37 including a resonance capacitor 31 and a loop antenna 32, and a second resonance circuit 38 including a resonance capacitor 33 and a loop antenna 34. The first resonance circuit 37 and the second resonance circuit 38 Connected by

Actually, an IC card 11 capable of being stacked on two sheets
As shown in FIG. 3, a resonance capacitor 31 is connected to a loop antenna 32 mounted along an outer peripheral edge on the substrate 15 to form a first resonance circuit 37. A resonance capacitor 34 is attached to the loop antenna 33 mounted on the inner peripheral side at a predetermined interval.
Are connected to form a second resonance circuit 38.

At this time, the IC card 11 compatible with two
Is set so that the resonance capacitors 34 of the second resonance circuit 38 are located at positions facing each other even when they are overlapped with another IC card 11 with their respective surfaces facing each other.

Further, the IC card 11 capable of being stacked on two sheets is
The first resonance circuit 37 and the second resonance circuit 38
5, the received power based on the electromagnetic wave received by the first resonance circuit 37 is
5 and to the electronic circuit 36 via the second resonance circuit 38.

As described above, the IC card 1 compatible with the two-layer stacking
1 is a distance between the loop antenna 32 of the first resonance circuit 37 and the loop antenna 33 of the second resonance circuit 38 by connecting the first resonance circuit 37 and the second resonance circuit 38 via the capacitor 35. , The received power can be supplied to the electronic circuit 36, and thus the degree of freedom in design is high.

The first resonance circuit 37 as a single-unit resonance means
Is set to a resonance frequency Fl _res that matches the carrier frequency F _{car of the} electromagnetic wave radiated from the data writing / reading device 21, and the second resonance circuit 38 as the resonance means is used when two IC cards 11 are stacked. Resonance frequency Fm _{res of} high frequency (carrier frequency F
_car × √2).

Therefore, as shown in FIG. 4 (A), in the case of the IC card 11 of the double-stackable type, if only one card is arranged so as to face the loop antenna 22 of the data writing / reading device 21, The carrier frequency F _car and the resonance frequency Fl _res of the first resonance circuit 37 match.

Thus, the two-layer-compatible IC card 1
1 is such that the electromagnetic wave radiated from the loop antenna 22 of the data writing / reading device 21 can be received most efficiently in a state where the carrier frequency F _car and the resonance frequency Fl _res of the first resonance circuit 37 match. ing.

As shown in FIG. 4 (B), in the IC card 11 of a double-stackable type, the IC card 11 is arranged so as to face the loop antenna 22 of the data writing / reading device 21 in a state where the two cards are stacked. If, the resonance frequency Fl _res of the first resonant circuit 37 is reduced to √2 times the carrier frequency F _car, the resonant frequency Fm _res of the carrier frequency F _car and a second resonant circuit 38 matches.

With this, the IC card 1 of the two-layered type can be used.
1 is such that the electromagnetic wave radiated from the loop antenna 22 of the data writing / reading device 21 can be most efficiently received in a state where the carrier frequency F _car and the resonance frequency Fm _res of the second resonance circuit 38 match. ing.

(2-2) IC Card of Three-Layer Type As shown in FIG. 5, in which parts corresponding to those in FIG. A first resonance circuit 43 including a loop antenna 41 and a loop antenna 42; a resonance capacitor 44 and a loop antenna 45;
A second resonance circuit 47 including a resonance capacitor 48;
And a third resonance circuit 50 including a loop antenna 49. The first resonance circuit 43, the second resonance circuit 47, and the third resonance circuit 50 are electromagnetically controlled by the loop antennas 42 and 45 and the loop antennas 46 and 49, respectively. Is trans-coupled.

Actually, an IC card 11 capable of being stacked on three sheets
6, a first resonance circuit 47 is formed by connecting a resonance capacitor 41 to a loop antenna 42 mounted along an outer peripheral edge of the substrate 15 as shown in FIG. The resonance capacitor 44 is connected to the loop antennas 45 and 46 mounted on the inner peripheral side at a predetermined distance away from each other to form a second resonance circuit 47. Further, the innermost peripheral side away from the loop antennas 45 and 46 by a predetermined distance The resonance capacitor 48 is connected to the loop antenna 49 mounted at the position of the third resonance circuit 50 to form a third resonance circuit 50.

At this time, the IC card 11 compatible with three
The resonance capacitor 44 of the second resonance circuit 47 and the resonance capacitor 4 of the third resonance circuit 50 are overlapped with each other even when the IC card 11 and another IC card 11 are stacked with their common surfaces facing each other.
Numerals 8 are set so as to face each other.

In this case, the IC card 1 compatible with three sheets stacked
Reference numeral 1 is such that the first resonance circuit 43, the second resonance circuit 47, and the third resonance circuit 50 are electromagnetically coupled to each other, not connected by a capacitor or the like, so that the circuit configuration can be simplified.

The first resonance circuit 43 as a single-unit resonance means
Is set to a resonance frequency Fl _res that matches the carrier frequency F _{car of the} electromagnetic wave radiated from the data writing / reading device 21, and the second resonance circuit 47 as the resonance means is used when two IC cards 11 are stacked. Resonance frequency Fm _{res of} high frequency (carrier frequency F
_car × √2), and the third resonance circuit 50 as a resonance means is a higher frequency resonance frequency Fh in anticipation of a decrease when three IC cards 11 are stacked.
_res (carrier frequency F _car × √3).

Therefore, as shown in FIG. 7 (A), in the IC card 11 of the three-stackable type, if only one card is arranged so as to face the loop antenna 22 of the data writing / reading device 21, The carrier frequency F _car and the resonance frequency Fl _res of the first resonance circuit 43 match.

As a result, the IC card 1 compatible with three sheets
1 is such that the electromagnetic wave radiated from the loop antenna 22 of the data write / read device 21 can be most efficiently received in a state where the carrier frequency F _car and the resonance frequency Fl _res of the first resonance circuit 43 match. ing.

Further, as shown in FIG. 7B, in the IC card 11 of a three-stackable type, the two IC cards 11 are arranged so as to face the loop antenna 22 of the data writing / reading device 21 in a state of being stacked. If, the resonance frequency Fl _res of the first resonant circuit 43 is reduced to 1 / √2 times the carrier frequency F _car, the resonant frequency Fm _res of the carrier frequency F _car and a second resonant circuit 47 matches.

As a result, the IC card 1 compatible with three sheets
1 is such that the electromagnetic wave radiated from the loop antenna 22 of the data writing / reading device 21 can be most efficiently received in a state where the carrier frequency F _car and the resonance frequency Fm _res of the second resonance circuit 47 match. ing.

Further, as shown in FIG. 7 (C), in the IC card 11 of the three-stackable type, the IC card 11 is arranged so as to face the loop antenna 22 of the data writing / reading device 21 in a state where the three cards are stacked. In this case, the resonance frequency Fl _res of the first resonance circuit 43 is reduced to 1 / √3 times the carrier frequency F _car , and the resonance frequency Fm _res of the second resonance circuit 47 is √2 / √3 times the carrier frequency F _car. But the carrier frequency F _car and the resonance frequency Fh of the third resonance circuit 50
matches _res .

As a result, the IC card 1 compatible with three-layer
1 is such that the electromagnetic wave radiated from the loop antenna 22 of the data write / read device 21 can be most efficiently received in a state where the carrier frequency F _car and the resonance frequency Fh _res of the third resonance circuit 50 match. ing.

In the above configuration, the IC card 11 is configured to set the resonance frequency Fm _res to a second resonance circuit 38 (a two-layer-compatible IC card) set at a high resonance frequency Fm _res in anticipation of a decrease in the resonance frequency Fl _res , or By providing the second resonance circuit 47 and the third resonance circuit 50 (three-layer-compatible IC cards) set on the high resonance frequencies Fm _res and Fh _res on the substrate 15, the second resonance circuit 47 and the other IC cards 11 When they are superimposed, the resonance frequency Fm _res of the second resonance circuit or the resonance frequency Fh _res of the third resonance circuit in the superimposed state can be matched with the carrier frequency F _{car of the} electromagnetic wave.

Thus, the IC card 11 can receive the electromagnetic wave radiated from the data writing / reading device 21 with the best reception efficiency even when two or three IC cards 11 are overlapped. .

Further, in the IC card 11, the first resonance circuit having the resonance frequency Fl _res matched with the carrier frequency F _{car of the} electromagnetic wave is provided on the substrate 15, so that even if only one card is used, the best resonance circuit is obtained. Electromagnetic waves can be received with a reception efficiency. Therefore, the IC card 11 can be used for the data writing / reading device 2 even when one or more cards are stacked.
1 can be received with the best reception efficiency.

According to the above configuration, the IC card 11 uses the second resonance circuit, which has been set to a high resonance frequency in anticipation of the decrease of the resonance frequency Fl _res in advance, or the second resonance circuit and the third resonance circuit, By installing on top of other IC
The electromagnetic wave radiated from the data writing / reading device 21 can be received with the best reception efficiency even when the card 11 is overlaid on the card 11, so that a plurality of cards can be received without sacrificing the communication distance and communication quality of one card. Even when they are overlapped, a sufficient communication distance and communication quality can be obtained.

In the above-described embodiment, in the IC card 11 of the two-stackable type, the first resonance circuit 37 and the second resonance circuit 38 constituting the antenna device are connected via the diode 35. , First resonance circuit 3
7, the received power based on the electromagnetic wave received is supplied to the electronic circuit 36. However, the present invention is not limited to this, and instead of connecting via the diode 35, the first resonance circuit 37 The reception power may be supplied to the electronic circuit 36 by electromagnetic coupling with the two-resonance circuit 38. In this case, effects similar to those of the above-described embodiment can be obtained.

Further, in the above-described embodiment, a case has been described in which the two- and three-stackable IC cards 11 are configured. However, the present invention is not limited to this, and the present invention is not limited to this. Accordingly, a plurality of resonance circuits may be provided to configure the IC card 11 of a stackable type.

Further, in the above-described embodiment, in the IC card 11 of the three-stackable type, the first resonance circuit 43, the second resonance circuit 47, and the third resonance circuit 50 constituting the antenna device are electromagnetically coupled. Although the description has been given of the case where the connection is made, the present invention is not limited to this, and the first resonance circuit 43, the second resonance circuit 47, and the third resonance circuit 50 are connected like the IC card 11 of the single-stacking type. You may make it connect via a diode.

Further, in the above-described embodiment, the two-layer and three-layer compliant IC cards 11 are connected to the same IC card.
Although the description has been given of the case where the cards are used by being overlapped with each other, the present invention is not limited to this, and the resonance frequency is lowered by being overlapped with the second resonance circuit and the third resonance circuit which are set higher than the carrier frequency F _{car in} advance. If it is tuned to the carrier frequency F _car at this time, it may be used by being superimposed on another type of IC card.

[0056]

As described above, according to the present invention, there is provided an antenna apparatus for receiving an electromagnetic wave via a resonance means, comprising a plurality of resonance means each having a different resonance frequency higher than a carrier frequency of the electromagnetic wave. When the device and another antenna device are close to each other, by tuning the resonance frequency lowered by one of the plurality of resonance means and the other antenna device to the carrier frequency of the electromagnetic wave,
An antenna device that can always receive electromagnetic waves with the best reception efficiency even when a plurality of antenna devices approach each other can be realized.

According to the present invention, in a card-shaped storage medium for writing and reading data to and from a predetermined electronic circuit in a non-contact manner via an electromagnetic wave, a plurality of resonance frequencies set to different resonance frequencies higher than the carrier frequency of the electromagnetic wave. When writing and reading data to and from the electronic circuit in a state where the card-shaped storage medium and the other card-shaped storage medium are close to each other, any one of the plurality of resonance means and the other card-shaped storage medium are provided. By tuning the reduced resonance frequency to the carrier frequency of the electromagnetic wave, it is possible to realize a card-shaped storage medium that can always receive an electromagnetic wave with the best reception efficiency even when a plurality of card-shaped storage media approach each other.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a contactless IC card system.

FIG. 2 is a connection diagram showing a configuration of a two-layer-capable IC card according to the present invention.

FIG. 3 is a schematic diagram showing a mounting image of a two-layer-capable IC card.

FIG. 4 is a characteristic curve diagram showing a transition of a reception characteristic and a tuning frequency in an IC card compatible with two-layer stacking.

FIG. 5 is a connection diagram showing the configuration of a three-stackable IC card according to the present invention.

FIG. 6 is a schematic diagram illustrating a mounting image of an IC card compatible with three-stacking;

FIG. 7 is a characteristic curve diagram showing a reception characteristic and a transition of a tuning frequency in a three-stackable IC card.

FIG. 8 is a block diagram showing a configuration of a conventional contactless IC card system.

FIG. 9 is a schematic diagram illustrating a tuning frequency when one IC card is used.

FIG. 10 is a connection diagram illustrating a configuration of an equivalent circuit when a plurality of IC cards are stacked.

FIG. 11 is a characteristic curve diagram showing a transition of a tuning frequency when a plurality of IC cards are stacked.

FIG. 12 is a characteristic curve diagram showing a transition of a tuning frequency in an IC card corresponding to a plurality of stacked cards.

[Explanation of symbols]

1, 10 ... non-contact IC card system, 2, 21 ...
Data writing / reading device, 6, 12, 22, 32, 34, 4
2, 45, 46, 49 ... loop antenna, 7, 31,
33, 41, 48 ... resonance capacitors, 35, 44 ...
Capacitor, 8 resonance circuit, 37, 43 first resonance circuit, 38, 47 second resonance circuit, 50 third resonance circuit.

Claims (8)

[Claims] 1. An antenna device for receiving an electromagnetic wave via a resonance means, comprising: a plurality of said resonance means set at different resonance frequencies, each higher than a carrier frequency of said electromagnetic wave; An antenna device for tuning a resonance frequency reduced by one of the plurality of resonance means and the another antenna device to a carrier frequency of the electromagnetic wave when the antenna approaches. 2. The antenna device according to claim 1, wherein the antenna device includes a single-unit resonance means for tuning to a carrier frequency of the electromagnetic wave when the antenna device is a single unit. 3. The antenna device according to claim 1, wherein each of the plurality of resonance means is electromagnetically coupled. 4. The apparatus according to claim 2, wherein each of said plurality of resonance means is electromagnetically supplied, and said single resonance means is electromagnetically coupled to any one of said plurality of resonance means. Antenna device. 5. A card-shaped storage medium for writing and reading data to and from a predetermined electronic circuit through an electromagnetic wave in a non-contact manner, comprising: a plurality of resonance means set to different resonance frequencies higher than the carrier frequency of the electromagnetic wave. When writing and reading data to and from the electronic circuit in a state where the card-shaped storage medium and another card-shaped storage medium are close to each other, one of the plurality of resonance means and the other card-shaped storage medium A card-shaped storage medium characterized by tuning the resonance frequency lowered by the carrier frequency to the carrier frequency of the electromagnetic wave. 6. The card-shaped storage medium according to claim 5, wherein said card-shaped storage medium includes a single-unit resonance means for tuning to a carrier frequency of said electromagnetic wave when said card-shaped storage medium is single. Storage medium. 7. The card-shaped storage medium according to claim 5, wherein each of the plurality of resonance circuits is electromagnetically coupled. 8. The apparatus according to claim 6, wherein each of said plurality of resonance means is electromagnetically coupled, and said single resonance means is electromagnetically coupled to any of said plurality of resonance means. Card-shaped storage medium.