FR3059122A1 - SAFETY DOCUMENT PROVIDED WITH AN ANTENNA - Google Patents

Abstract

The invention relates to a system for verifying the authenticity of a security document (1), comprising on the one hand a set of security documents (1) associated with users, and on the other hand readers (8). ) intended to verify the authenticity of said documents (1), characterized in that each security document comprises a passive antenna (5) having at least a first resonance frequency (F0D) constituting an electromagnetic signature (16) of said document, and in that each reader (8) comprises a measuring loop (13) capable of measuring the electromagnetic signature of a document (1) when it is approached from the reader (8), and an electronic circuit (9) for comparing this electromagnetic signature with a reference electromagnetic signature (F0R) stored in said reader (8) or on said security document (1).

Description

© Publication no .: 3,059,122 (use only for reproduction orders)

©) National registration number: 16 01646 ® FRENCH REPUBLIC

NATIONAL INSTITUTE OF INDUSTRIAL PROPERTY

COURBEVOIE

©) Int Cl ⁸ : G 06 K 7/10 (2017.01), G 06 K 19/08, B 42 D 25/305

A1 PATENT APPLICATION

©) Date of filing: 21.11.16. © Applicant (s): IMPRIMERIE NATIONALE Company (30) Priority: anonymous— FR. ©) Inventor (s): COMBRET FABIEN, MEAR BENJA- MIN and KAMBOURIAN HAIG. (43) Date of public availability of the request: 25.05.18 Bulletin 18/21. (56) List of documents cited in the report preliminary research: Refer to end of present booklet (© References to other national documents ©) Holder (s): IMPRIMERIE NATIONALE Société ano- related: nyme. ©) Extension request (s): @) Agent (s): GLOBAL INVENTIONS.

SAFETY DOCUMENT PROVIDED WITH AN ANTENNA.

FR 3 059 122 - A1

VyJ The invention relates to a system for verifying the authenticity of a security document (1), comprising on the one hand a set of security documents (1) associated with users, and on the other hand readers ( 8) intended to verify the authenticity of said documents (1), characterized in that each security document comprises a passive antenna (5) having at least a first resonant frequency (F _pD ) constituting an electromagnetic signature (16) of said document , and in that each reader (8) comprises a measurement loop (13) capable of measuring the electromagnetic signature of a document (1) when the latter is approached to the reader (8), and an electronic circuit (9) to compare this electromagnetic signature with a reference electromagnetic signature (F _or ) stored in said reader (8) or on said security document (1).

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Security document with antenna

The invention relates to the security of official documents or other official documents, such as passports, identity cards, driving licenses, automobile registration cards, etc.

State of the art

In the current state of the art, the security of official documents without electronic circuits is conditioned by the presence of security patterns printed on the surface of the document, or integrated into one of the constituent layers of the document.

Thus, tactile elements are used printed on the surface of documents, complex patterns such as guilloches, or holograms that are difficult to reproduce. To verify the authenticity of this type of document, it is usually sufficient to have a visual examination.

Other official documents may have internal layers into which information can be written using a laser beam. In this case the verification of authenticity generally requires additional means, in particular lighting, to be able to verify the information hidden inside the document.

Even more secure documents are also known, using a microelectronic chip to store coded and / or encrypted security information. In the so-called "contactless" versions of these documents, the chip is connected to an antenna, so as to allow radio frequency communication with an external contactless reader.

While chip products are likely to have a higher level of security, they are also more expensive and more complex to manufacture and implement, which is not suitable for all markets. Indeed, certain markets would need, for reasons of cost, documents that are less expensive than a microelectronic chip document, while presenting a higher level of security than documents simply provided with a security motif printed on the surface, or integrated in the thickness of the document.

Aims of the invention

A general aim of the invention is therefore to propose security documents which are devoid of the aforementioned drawbacks.

Another object of the invention is to propose a technical solution making it possible to increase the resistance of documents to fraud, at a lower cost, that is to say even when they do not have a microelectronic chip.

Another object of the invention is to provide documents whose authenticity can be effectively verified by a simple and inexpensive infrastructure.

Summary of the invention

The subject of the invention is therefore a system for verifying the authenticity of a security document, comprising on the one hand a set of security documents associated with users, and on the other hand readers intended to verify the authenticity of said documents, characterized in that each security document comprises a passive antenna having at least a first resonance frequency (F _0D ) constituting an electromagnetic signature of said document, and in that each reader comprises a measurement loop capable of measuring the electromagnetic signature of a document when the latter is approached to the reader, and an electronic circuit for comparing this electromagnetic signature with a reference electromagnetic signature (For) stored in said reader or on said document.

Thus, when the comparison is positive, the verifier using the system has a reliable and reliable indication that the document presented to the reader is an authentic document.

According to an advantageous embodiment of the invention, each reader of the system further comprises a reported or integrated passive antenna, having a second resonant frequency (Fol) so that when the passive antenna of the document and the passive antenna of the reader are coupled together, they have a complex resonant frequency F (old) having several resonance peaks and constituting a complex electromagnetic signature of said document.

According to the invention, each reader comprises signaling means for indicating, as a function of the result of the comparison carried out by the reader, the fact that the security document presented is an authentic document, and if not, the fact that the document presented is a forgery.

Advantageously, said signaling means are LED type light display means, or sound means.

In an even safer version of the system according to the invention, each document comprises, in addition to its passive antenna having a resonance frequency (Fod), a coded graphical representation of said resonance frequency (F _0D ), and each reader comprises furthermore an optical sensor and a microcontroller for reading and for decoding said graphic representation.

The graphic representation of the resonance frequency (F _0D ) of the documents is for example a QR code.

In an advantageous embodiment of the documents of the system, the tracks of the passive document antenna and the QR code are produced on a single metallic layer integrated into the thickness of the document, and protected by external layers.

Other characteristics and advantages of the invention will appear on reading the detailed description and the appended drawings in which:

FIG. 1 represents an exploded perspective view of a document according to the invention, in the format of a card;

Figure 2 shows a card reader in schematic form; FIG. 3 represents the frequency response of the reader alone, equipped with an antenna, the frequency response of a single card according to the invention, equipped with an antenna, and the frequency response of the system constituted by the reader Figure 2 and the map of Figure 1;

FIG. 4 represents a variant card according to the invention, provided with an antenna and a QR code;

FIG. 5 represents a functional flow diagram of the test software executed by the reader for the test of cards according to FIG. 1, without QR code;

FIG. 6 represents a functional flow diagram of the test software executed by the reader for the test of cards according to FIG. 4, with a QR code on the cards tested.

detailed description

FIG. 1 shows a security document 1, in the format of a plastic card having dimensions in accordance with standard ISO 7816-1. Of course this form factor is only a practical example, the form factor îo of the document is in no way limitative of the scope of the invention.

Most of the existing security documents are plastic cards simply comprising on the external layers printed information relating to the card issuer, and graphic information relating to the card holder, for his identification. The information on the card is intended to be read either by a human controller or by a scanner-type acquisition device connected to a system for digitizing and processing the information read. In this context, these cards are very simple and do not include a microelectronic chip or an antenna.

The principle of the invention consists, on the contrary, in providing security documents, for example cards 1 such as that of FIG. 1, with a passive antenna 5 intended to interact with an antenna of a card reader. The antenna 5 of the card is not arbitrary, it is chosen to have a certain particular electromagnetic signature, in particular a particular and calibrated resonant frequency.

For the rest of the presentation, it will be considered that the electromagnetic signature of an antenna is represented in a simplified manner by its resonant frequency. We will therefore associate a given resonant frequency with a given type of card. Thus, all cards or documents issued by a given authority, will have their own unique resonant frequency.

In a basic version of the invention, the card readers of the system, such as the reader 8 shown diagrammatically in FIG. 2, will be equipped with a microcontroller 9 provided with a memory (not shown) in which is stored a value of reference resonance frequency noted For, corresponding to that of the authentic documents used in the system. The readers 8 also include a measuring coil 13 for the resonance frequency of a document 1 that a user will approach the reader. The measurement of the resonant frequency of the antenna 5 of document 1 is transmitted in the microcontroller 8 to a circuit for comparing the resonant frequency detected from the card with the reference resonant frequency F _0R stored in memory. Finally, the readers 8 include signaling means (optical, audible, etc.), such as for example the LEDs 11, 12, to signal the result of the comparison to the user of the system and to indicate to him that a document tested. given corresponds to an authentic document or a falsified document.

It is therefore easy to understand that the specific antenna 5 integrated in each document 1 increases the resistance of the document to falsification, since a fraudster will have to have the means of retrofitting a false document, with an antenna having the same electromagnetic signature, in particular the same resonant frequency, as authentic documents.

However, the integration of such an antenna 5 into a document remains within the reach of networks of fraudsters structured and equipped with equipment for copying antennas.

We must therefore go further.

To this end, a slightly more advanced version of the invention also plans to equip the readers 8 with a specific passive antenna 14, also called de-tuning antenna, having its own characteristic resonant frequency. In this case, when approaching the reader 8 a document 1 according to the invention and provided with its own antenna 5, one obtains a system of two antennas 5, 14 coupled together, and having a complex electromagnetic signature 17, as shown in Figure 3, including in particular two or more resonance peaks which can be detected by the measuring coil 13 of the reader.

As shown in FIG. 3, suppose that the antenna 14 of the reader 8 has a resonance frequency 16 slightly less than 13 Mhz, and that the antenna 5 of document 1 has a resonance frequency 17 a little greater than 13 Mhz. Then the antenna system 5, 14 coupled together will have their own electromagnetic signature 18, having two resonance peaks, for example in the vicinity of 11 and 16 MHz.

Again, the electromagnetic signature expected from the pair of antennas 5, 14 is stored in the memory of the reader 8, and for each new document approached by the reader, the latter will compare the memorized electromagnetic signature with the electromagnetic signature detected for the system constituted by the passive antenna 14 of the reader coupled with the passive antenna 5 of the new document to be tested.

As the electromagnetic signature 18 of the antenna system 5, 14 is more complex than in the previous case with a single antenna 5 located on the document, it becomes more difficult to replicate fraudulently, but this remains possible with the appropriate means. .

In a still a little safer version of the system according to the invention, the documents 1 and the readers 8 are still equipped as before with specific antennas 5, 14, but a secret mathematical processing member is added to the reader in addition. to further complicate the electromagnetic signature of the antenna system constituted by the passive antenna 14 of the reader coupled with the passive antenna 5 of a document.

For example, the reader software will calculate a fictitious resonant frequency F _O f by a processing of the type:

F _O f = A.Fol + B.Fod where A and B are integer parameters or not, and F _0L and

F _O d respectively represent the resonance frequency of the passive antenna 14 of the reader, and the resonance frequency of the passive antenna 5 of the document.

Of course, the same processing will have been applied before the reference resonance frequencies of the reader and of an authentic document, in order to be able to store in memory the expected target value.

As we can see, in order to obtain a falsified document having the correct electromagnetic signature 17, in particular the correct resonant frequencies, it will now be necessary to have the resonant frequency 16 of the reader 8, that of an authentic document 5, and parameters A, B of the secret operation carried out in the reader.

According to a preferred and even safer variant of the invention, each security document 1 provided with its antenna 5, will include, as shown in FIG. 4, a coded graphical representation 15 of the electromagnetic signature of its antenna 5, in particular of its resonant frequency

16. And each reader 8 will be equipped with means for reading this coded graphical representation when the document 1 is approached by the reader 8, for decoding it and for comparing it with the reference resonance frequency 17 expected and stored in the memory of the reader. In this case, it is possible to do without a passive antenna 14 on each reader, but the readers must include, io as shown diagrammatically in FIG. 2, an optical sensor 10 for reading the coded graphic representation 15 placed on the card.

In practice, the coded graphical representation 15 of the value of the resonance frequency of the antenna of a document will for example consist of a QR code printed on one of the layers 2, 3, 4, 6, 7 of the menu. This kind of code is very difficult to replicate. However, other coded graphic representations, such as in particular 2D bar codes, are conceivable.

Depending on the location of the QR code or equivalent, it may be useful for the plastic layers located above the QR code to be transparent, or to have a transparent window, to facilitate reading of the QR code by the optical sensor 10 of the reader 8 .

To further increase system security, the resonant frequency values stored in a QR Code can be accompanied by digital protection for authenticity, integrity or confidentiality. For example, for authenticity and integrity, the data integrated into the QR code is digitally signed beforehand using an asymmetric private key provided by the document issuer. To verify the signature, the corresponding public key certificate must be obtained from the entity that generated and certified the asymmetric key.

For confidentiality, the data is encrypted with a symmetric key provided by the issuer of the document. To decipher the QR Code, it is necessary to use the symmetric key which is distributed, as is well known in the state of the art.

In an advantageous embodiment of the invention, the tracks of the antenna 5 of the document 1 and the QR code 15 will be produced on a single metal layer integrated into the thickness of the document during the manufacture of the latter. . Thus any manipulation of the antenna 5 and the QR code 15 will become visible.

Preferably, the reader comprises means of visual or audible signaling of the result of the comparison between the value of the resonant frequency of the document tested and the reference value stored in the reader. These means take, for example, the form of a green LED 11 to indicate that the document presented is authentic, and a red LED 12 to indicate that the document Io presented is a forgery.

In FIG. 5, the functional flow diagram of the reader test software 8 has been represented in the case where the documents tested 1 do not include a coded graphical representation of their resonance frequency. In this case, the reader 8 goes into a waiting loop 20 of a card to be tested, then when a card 1 arrives near the reader 8, the reader measures its resonant frequency Fo, then reads 22 l electromagnetic fingerprint F _0R stored in the memory of the reader. At 23, the microcontroller 9 of the reader 8 compares the measured resonant frequency with the reference resonant frequency stored in memory. In case of equality of the two resonant frequencies, the document 1 presented is deemed authentic, which is for example indicated at 24 by the lighting of the green LED. Otherwise, the document 1 presented is deemed to be non-authentic, which is indicated for example at 25 by the lighting of the red LED.

In FIG. 6, the functional flow diagram of the reader test software 8 has been represented in the case where the documents tested comprise both several resonance frequencies F _o , F _o ', F _o and a graphic representation of these resonance frequencies. , such as a QR code. The electromagnetic reference signature stored in the memory of the reader is then for example the sum Fo + F _o '+ F _o of the resonance frequencies of authentic cards, and this signature is stored, during the manufacture of the card, at the same time in the graphic representation like the QR code, and in the memory of the reader 8.

Thus, to verify the authenticity of a document or a card approached at 20 of the reader, the reader measures at 21 the resonance frequency or frequencies of the document to be tested, then at 26 it reads the QR code or equivalent located on the document, it calculates at 27 the sum of the resonance frequencies measured, and at 28 it compares the sum calculated with the QR code read and possibly with the signature stored in the memory of the reader 8. In case of correspondence of all the elements, the card is deemed authentic and the green LED is lit at 24, otherwise the red LED is lit at 25.

It should be noted that in the case where a QR code is used, the reader does not necessarily need to be equipped with a de-tuning antenna 14, since the level of security obtained thanks to the use of a QR code is sufficient.

Advantages of the invention

The invention meets the set goals. Thanks to the invention, it is possible to simply verify the authenticity of a sovereign document, while the security means implemented represent a minimal cost.

In addition, the solution of the invention has great flexibility, since the cards can be personalized by country (a resonance frequency by country for example) or by customer. The choice of the card resonance frequency can be made at the last moment during the card manufacturing process, by laser machining of the antenna tracks.

Security is increased compared to a sovereign document without a chip comprising only conventional security means: to hope to counterfeit the document according to the invention, laboratory level knowledge is necessary.

In addition, any attempt to deactivate security, for example by cutting or modifying the antenna of the card or by deleting the QR code, will leave visible traces on the card.

Finally, the lifespan of the security document is very long, since the additional means consist of a simple antenna easy to integrate, without electronic module.

The technique of the invention could also be adapted as additional security for documents with a chip, even if in this case security as economical as in the case of documents or cards without a chip would not be obtained.

Claims (8)

1 - System for verifying the authenticity of a security document (1), 5 comprising on the one hand a set of security documents (1) associated with users, and on the other hand readers (8) intended to verify the authenticity of said documents (1), characterized in that each security document (1) comprises a passive antenna (5) having at least a first resonance frequency (Fod) constituting an electromagnetic signature (16) of said document, and in that each reader (8) comprises a measurement loop (13) suitable measuring the electromagnetic signature of a document (1) when it is approached to the reader (8), and an electronic circuit (9) to compare this electromagnetic signature with an electromagnetic reference signature (F _O r) stored in said reader (8) or on said security document (1). 2 - Verification system according to claim 1, characterized in that each reader (8) further comprises a passive antenna (14) having a second resonant frequency (17) so that when the passive antenna (5) of the document (1) and the passive antenna (14) of the reader (8) are coupled together, 20 they have a complex resonance frequency (18) having several resonance peaks and constituting an electromagnetic signature of said document. 3 - System according to claim 1 or claim 2, characterized in that each reader (8) comprises signaling means (11,12) for 25 indicate, depending on the result of the comparison made by the reader (8), the fact that the security document (1) presented is an authentic document, and if not, the fact that the document presented is a forgery. 4 - System according to claim 3, characterized in that said means 30 signaling are LED type light display means (11,12), or sound means. 5 - System according to any one of the preceding claims, characterized in that each security document (1) comprises, in addition to its passive antenna (5) having a resonant frequency (F _0D ), a coded graphic representation (15 ) of said resonant frequency (F _0D ), and in that each 5 reader (8) further comprises an optical sensor (10) and a microcontroller (9) for reading and for decoding said graphic representation (15). 6 - System according to claim 5, characterized in that said graphical representation (15) of the resonance frequency (F _O d) of documents îo is a QR code. 7 - System according to claim 6, characterized in that the tracks of the passive antenna ((5) of the document (1) and the QR code are produced on a single metal layer integrated into the thickness of the document. 8 - System according to one of claims 5 to 7, characterized in that the coded graphic representation (15) incorporates digital protection in authenticity, integrity or confidentiality. 1/4 figure i ,, - 7 2/4