JPH0583867U - Memory card - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent tampering reliably and realize high reliability, and to store a large amount of information with a few resonant circuits. [Structure] A plurality of resonance circuits 2r, 3r, 4 using the inductance and capacitance of the planar coils 2, 3, 4.
r is built in and each resonance circuit 2r, 3r, 4r is made into a different state, and information is memorized. Inside each coil 2, 3, 4
The same or different magnetic cores 2i, 3i, 4i are selectively arranged to make the resonance frequencies of the resonance circuits 2r, 3r, 4r different.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a storage card suitable for use as an ID card or the like that stores identification information.

[0002]

[Prior Art]

 Generally, a storage card such as an ID card that stores identification information for identifying a specified person is known.

FIG. 2 shows a conventional storage card. The memory card 20 shown in the figure has a plurality of, for example, six different plane coils 22a, 22b, 22c ... The plane coils 22a and 22c were broken. As a result, the normal plane coils 22b, 22d, 22e function as a resonance circuit due to the inductance of the coil and the line capacitance of the coil. Therefore, the reference numeral "1" is assigned and the broken plane coils 22a, 22c have a circuit function. Therefore, if the code “0” is assigned, the storage card 20 illustrated in FIG. 2 stores the identification information by the code “01011”, and functions as a ROM.

The storage card 20 as described above is read by a predetermined reading device. That is, the storage card 20 resonates the resonance circuit formed by the plane coils 22b, 22d, and 22e by the radio waves transmitted from the reading device, and transiently reradiates the radio waves (secondary radiation) even after the transmission is stopped. The code "1" or "0" is read by detecting the presence or absence of the secondary radiation by the reading device.

[0005]

[Problems to be solved by the device]

 However, the above-mentioned conventional storage card 20 has the following problems.

First, since the stored identification information can be easily tampered with, it lacks reliability. In particular, if a hole is intentionally made in the storage card 20, the code "1" can be easily tampered with by the code "0".

Secondly, since the identification information is represented by the code “1” or “0”, the amount of information that can be stored is up to 2 ⁿ when the number of the planar coils 22a ... The amount of information is extremely limited.

The present invention solves the problems existing in such conventional techniques, and prevents the tampering of stored information with reliability to dramatically improve the reliability and to reduce the number of resonance circuits. The purpose is to provide a memory card capable of storing a large amount of information.

[0009]

[Means for Solving the Problems]

 The present invention incorporates a plurality of resonant circuits 2r, 3r, 4r using the inductance and capacitance of a coil, for example, planar coils 2, 3, 4 and sets the respective resonant circuits 2r, 3r, 4r in different states to provide information. When constructing a storage card 1 such as an ID card to be stored, in particular, the same or different magnetic material cores 2i, 3i, 4i are selectively arranged inside each coil 2, 3, 4, respectively. It is characterized in that the resonance frequencies of the resonance circuits 2r, 3r, 4r are different.

In this case, the magnetic cores 2i, 3i, 4i can be made different in one or both of area and material, and the capacitance can utilize the line capacitance of the planar coils 2, 3, 4.

[0011]

[Action]

 According to the memory card 1 of the present invention, magnetic cores 2i, 3i, 4i having different shapes or materials or both are selectively disposed inside each planar coil 2, 3, 4. Therefore, the resonance frequency of each resonance circuit 2r, 3r, 4r changes according to the area, magnetic permeability, etc. of each magnetic core 2i, 3i, 4i.

That is, generally, the resonance frequency fo has a relationship of fo ² = 1 / (4π ² LC) when L is an inductance and C is a capacitance, and when the inductance L is changed, the resonance frequency fo is also changed. To do. Further, the inductance L changes depending on the area, magnetic permeability, etc. of the magnetic cores 2 i, so that the resonance frequency fo changes depending on the type of the magnetic cores 2 i, 3 i, 4 i.

Therefore, when writing the final identification information to the storage card 1, the magnetic cores 2i, 3i, 4i which are the same or different from each other are selectively arranged with respect to the resonance circuits 2r, 3r, 4r created in advance. For example, if the number of each planar coil 2 ... Is n and the type of the magnetic cores 2i ... Is m, the memory card 1 should be written with ^mn types as identification information. You can

[0014]

【Example】

 Next, preferred embodiments according to the present invention will be described in detail with reference to the drawings.

First, the structure and function of the storage card 1 according to the present invention will be described with reference to FIG.

In the storage card 1 shown in FIG. 1, 10 is a base plate, and three different circular planar coils 2, 3, 4 are arranged on the surface of the base plate 10. The plane coils 2, 3 and 4 form a resonance circuit 2r, 3r, 4r by the inductance of each coil itself and the line capacitance of each coil.

Further, magnetic cores 2i, 3i, 4i having different shapes are arranged inside each of the planar coils 2, 3, 4. In the embodiment, the small circular magnetic core 2i formed of a flat plate is used as the plane coil 2, the rectangular magnetic core 3i made of the same material is used as the plane coil 3, and the large circular magnetic core 4i made of the same material is used. The case where they are respectively arranged on the plane coils 4 is illustrated.

The planar coils 2 and the magnetic cores 2i can be arranged on the base plate 10 by sticking, printing, or the like, and can be attached or printed on a separate sheet or the like to be superposed. It can also be arranged. As a result, the resonance frequency of each resonance circuit 2r, 3r 4, 4r is set to a different value according to the magnetic cores 2i, 3i, 4i.

Therefore, in the storage card 1 according to the present invention, when the number of the plane coils 2 ... Is n and the type of the magnetic cores 2i ... (including the air core) is m, m ⁿ types can be expressed as identification information. Wear. For example, as shown in FIG. 1, there are three resonance circuits, 2r, 3r, and 4r, and it is possible to set four kinds of resonance frequencies that do not overlap with any other resonance frequency for one resonance circuit. For example, there are a total of 3 × 4 = 12 types of resonance frequencies, and 4 ³ = 64 types of information can be expressed.

For example, the resonance frequency f of the resonance circuit 2r₀₀, F₀₁, F₀₂, F₀₃Assign a numerical value of 0 to 3 to 4⁰The resonance frequency f of the resonance circuit 3r._Ten, F₁₁, F₁₂ , F₁₃Assign a numerical value of 0 to 3 to 4¹And the resonance frequency f of the resonance circuit 4r.₂₀, F_{twenty one}, F_{twenty two}, F_{twenty three}Assign a numerical value of 0 to 3 to 4²In this case, the resonance frequency of each resonance circuit 2r, 3r, 4r is f ₀₁ , F₁₂, F_{twenty three}If set to 3, the stored identification information (identification number) is 3 × 4.²+2 x 4¹+1 x 4⁰= 57.

Next, a reading device for reading the identification information stored in the storage card 1 will be described with reference to FIG.

The reader 30 includes a signal processor 31, an oscillator 32, an amplifier 33, a transmitting antenna 34, a receiving antenna 35, an amplifier 36, a tuner 37 and a detector 38, and operates as follows. First, the signal processor 31 outputs a frequency select signal and a timing signal for sequentially transmitting and receiving all the resonance frequencies of the storage card 1, and they are given to the oscillator 32 and the tuner 37. As a result, the oscillator 32 outputs a transmission signal whose oscillation frequency changes sequentially, and the transmission signal is amplified by the amplifier 33 and then radiated from the transmission antenna 34 by radio waves for a short time.

At this time, if the storage card 1 is present in the vicinity of the reading device 30, since the radio wave from the transmitting antenna 34 is received, the resonance circuits 2r, 3r, 4r resonate, thereby transiently transmitting the radio wave. Secondary radiation to.

Therefore, since the radio wave radiated secondarily from the storage card 1 is received by the receiving antenna 35, the received signal obtained from the receiving antenna 35 is amplified by the amplifier 36 and then given to the tuner 37. Since the tuning frequency changes in the tuner 37 according to the frequency select signal and the timing signal, the detector 38 detects the presence or absence of the secondary radiation from the storage card 1 by the signal level from the tuner 37. As a result, the signal processor 31 reads the identification information (identification number) stored in the storage card 1 by the detection signal from the detector 38, and gives it to, for example, a predetermined control device 40 or the like.

The reading device 30 always reads one resonance frequency from each resonance circuit 2r, 3r, 4r at the time of reading. That is, one from the resonance frequencies f ₀₀ , f ₀₁ , f ₀₂ , and f ₀₃ , one from the resonance frequencies f ₁₀ , f ₁₁ , f ₁₂ , and f ₁₃ and one from the resonance frequencies f ₂₀ , f ₂₁ , f ₂₂ , and f _23. Since one is read, a total of three resonance frequencies can be received. Therefore, it can be regarded as normal only when three resonance frequencies are received, and as abnormal when other combinations or resonance frequencies other than the original quantity are received, and error detection of information can be performed easily. You can

Although the embodiments have been described in detail above, the present invention is not limited to such embodiments. For example, the capacitance uses the line capacitance of the plane coil, but a separate capacitor may be used. Further, although the same number of resonance frequencies is given to each resonance circuit, the resonance frequencies do not necessarily have to be equal. Furthermore, although the magnetic cores are different in each resonance circuit, they may be the same. Further, although the ID card is exemplified, it can be applied to any other storage card. In addition, the detailed configuration, quantity, conditions, etc. can be arbitrarily changed without departing from the scope of the present invention.

[0027]

[Effect of the device]

 As described above, the present invention has a plurality of resonance circuits using the inductance and capacitance of the coils, and stores the information in the respective resonance circuits in different states. Since different magnetic material cores are selectively arranged to make the resonance frequencies of the respective resonance circuits different, the following remarkable effects are obtained.

Tampering with the identification information stored in the storage card can be reliably prevented, reliability can be dramatically improved, and error detection of information can be easily performed.

When the number of planar coils is n and the type of magnetic core is m, m ⁿ types can be written as identification information in the storage card, and a large amount of information can be stored with a small number of resonance circuits.

[Brief description of drawings]

FIG. 1 is an internal configuration diagram of a storage card according to the present invention,

FIG. 2 is an internal configuration diagram of a storage card according to a conventional technique,

FIG. 3 is a block circuit diagram of a reading device that reads identification information stored in a storage card.

[Explanation of symbols]

 1 Storage Card 2, 3, 4 Planar Coil 2i, 3i, 4i Magnetic Core 2r, 3r, 4r Resonant Circuit

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display location G06K 19/10

Claims (4)

[Scope of utility model registration request] 1. In a storage card, which stores a plurality of resonance circuits using the inductance and capacitance of coils and stores each resonance circuit in a different state, the same or different magnetic material core is provided inside each coil. A memory card characterized in that the resonant frequencies of the resonant circuits are made different by selectively arranging. 2. The memory card according to claim 1, wherein one or both of the shape and the material of the magnetic core are different. 3. The storage card according to claim 1, wherein the capacitance uses the line capacitance of the coil. 4. The storage card according to claim 1, which is applied to an ID card.