Method for determining the state of an antenna

Abstract

The invention relates to a method (1000) for determining a state of a near-field communication antenna, implemented by computer within a terminal comprising: - the near-field communication antenna, - a near-field communication integrated circuit configured to be connected to the antenna, wherein the following steps are implemented: - determining (1010, 1020), within the integrated circuit, at least one voltage or intensity value, - deriving (1030), from the voltage or intensity value determined within the integrated circuit, an operating or malfunctioning state of the antenna.

Description

Method for determining the condition of an antenna

[0001] The invention relates to near-field communication. It relates in particular to electronic payments made "contactless" between a payment terminal and a payment device.

[0002] Near-field communication (NFC), often referred to by its acronym "NFC", is a short-range wireless communication technology that allows the exchange of information between devices located a short distance from each other. In particular, in the payment sector, it allows contactless payments to be made between a payment terminal and a payment device such as a bank card.

[0003] A terminal comprising a near-field communication function, such as a payment terminal configured to carry out contactless transactions with a payment device, comprises a near-field communication antenna, connected, via an impedance matching circuit, to a near-field communication integrated circuit. This near-field communication circuit generally comprises electronic components for powering and controlling the antenna, configured to provide the antenna with the signals to be transmitted and to process the signals received by the antenna. This near-field communication circuit is generally in the form of an electronic chip to which the impedance matching circuit is connected by one or two pins. In the payment field, this near-field communication circuit is specifically configured to comply with security standards associated with contactless transactions.

[0004] In the state of the art, when a terminal including a near-field communication function fails, it is necessary to disassemble the terminal to identify the source of the malfunction. A fault may come from the antenna, but also from the impedance circuit, the near-field communication integrated circuit, or another element of the terminal. It is therefore necessary to examine each of these elements in turn.

[0005] However, such an operation is complex, long and tedious.

[0006] The invention aims in particular to quickly and immediately identify, within a terminal equipped with a near-field communication function, whether the antenna is the cause of a malfunction of the near-field communication function, without having to dismantle the terminal and examine the antenna.

[0007] To this end, the invention relates to a method for determining the state of a near-field communication antenna, implemented by computer within a terminal comprising:

[0008] - the near-field communication antenna,

[0009] - a near-field communication integrated circuit configured to be connected to the antenna,

[0010] in which the following steps are implemented:

[0011] - determination, within the integrated circuit, of at least one voltage or current value,

[0012] - deduction, from the voltage or current value determined within the integrated circuit, of an operating or malfunctioning state of the antenna.

[0013] Indeed, outside the invention, this value of intensity or voltage internal to the near-field communication integrated circuit is used for other purposes, in particular for the purpose of regulating or amplifying a signal within the circuit. However, it appears that if the antenna is faulty, this value varies systematically and in a similar manner. By obtaining it at any time, it is therefore possible to deduce a fault in the antenna, without having to dismantle the terminal and examine the antenna.

[0014] Other optional features follow, taken alone or in combination.

[0015] Advantageously, the integrated communication circuit comprising:

[0016] - a transmitter to transmit a signal to the antenna,

[0017] - a dynamic power control unit for regulating a power of a signal transmitted by the transmitter to the antenna,

[0018] the step of determining a value comprises a determination of a voltage across the transmitter and / or a step of determining an intensity flowing through the transmitter.

[0019] Thus, in the case where the integrated circuit has a transmitter and a control unit for regulating the power supplied to the antenna, it is at least one of the values ​​among a voltage value and an intensity value associated with this transmitter which makes it possible to deduce the state of the antenna. Indeed, the control unit varies these values ​​so as to respect a setpoint. However, it appears that it varies these values ​​differently when the antenna is faulty.

[0020] Preferably, the deduction step comprises deducing, from the determined voltage and / or current, at least one operating or malfunctioning state of the antenna among the following states:

[0021] - the antenna is connected to the communication integrated circuit;

[0022] - the antenna is disconnected from the communication integrated circuit;

[0023] - an antenna track is disconnected from the communication circuit;

[0024] - two antenna tracks are disconnected from the communication circuit.

[0025] Indeed, it appears that the control unit varies the intensity and / or voltage values ​​in a specific manner when the antenna is disconnected or only one of its two tracks is cut. It is therefore possible to obtain a precise state of the antenna. In the case where it appears from the determined value(s) that only one track is cut, it is possible to carry out a maintenance operation by configuring the antenna or other components of the terminal differently in view of this partial defect so that the near-field communication function continues to operate. It is also possible to carry out a preventive or even predictive maintenance operation by replacing the antenna before the near-field communication function malfunctions completely.

[0026] Advantageously, the integrated communication circuit comprising two signal reception pins intended to be connected to the antenna, the determination step comprises the determination of a signal amplitude value at the two reception pins.

[0027] Thus, in the case where the communication integrated circuit has these two pins and makes accessible an amplitude value associated with these two pins, it appears that this value varies according to the state of the antenna so that its reading makes it possible to deduce a state of the antenna.

[0028] Preferably, the deduction step comprises deducing, from the determined differential value, at least one operating or malfunctioning state of the antenna among the following states:

[0029] - the antenna is connected to the communication integrated circuit;

[0030] - the antenna is disconnected from the communication integrated circuit or has at least one cut track.

[0031] The invention also provides a computer program comprising instructions which, when the program is executed by a computer, cause the latter to implement the steps of the method described above.

[0032] The invention also provides a computer-readable recording medium comprising instructions which, when executed by a computer, cause the computer to implement the steps of the method described above.

[0033] The invention also provides a terminal comprising:

[0034] - a near-field communication antenna,

[0035] - a near-field communication integrated circuit configured to be connected to the antenna,

[0036] - a processor configured to implement the steps of the method described above.

[0037] By "configured for" is meant that an element has means and / or has settings specifically adapted to a particular use. Here, the processor has electronic components, a configuration, and is associated with computer programs, specifically adapted to the implementation of the methods described.

[0038] The invention also provides a terminal as described above, configured to carry out a contactless electronic payment.

[0039] In particular, its near-field communication integrated circuit is configured to comply with standards relating to contactless banking transactions. Brief description of the figures

[0040] The invention will be better understood on reading the following description, given solely by way of example and with reference to the appended drawings in which:

[0041] is a block diagram of a near field communication integrated circuit used for the invention;

[0042] is a flowchart of a method of implementing the invention using the circuit of the;

[0043] is a block diagram of another near field communication integrated circuit used for the invention;

[0044] is a flowchart of a method of implementing the invention using the circuit of the. Detailed description

[0045] Throughout the application, “near-field communication” means any communication using “near-field communication” (NFC) technology. NFC technology is a short-range, high-frequency wireless communication technology that allows the exchange of information between devices within close range of each other, typically ten centimeters or less. It is covered by norms and standards known to those skilled in the art.

[0046] A device configured to use this technology is commonly referred to as an “NFC device.” An NFC device includes at least one near-field communication antenna and a near-field communication integrated circuit connected to that antenna.

[0047] Throughout the application, the term “near field communication antenna” refers to an antenna configured to use NFC technology. In particular, it has characteristics that comply with the norms or standards associated with NFC technology.

[0048] Throughout the application, the term “near field communication integrated circuit” refers to an integrated circuit comprising electronic components connected together to process signals to be emitted by a near field communication antenna, or signals received by this antenna. This circuit also has characteristics that comply with the norms or standards associated with NFC technology.

[0049] In English, such a circuit is commonly referred to as an "NFC IC" (IC for "integrated Circuit"). A near-field communication circuit may be referred to by other names known to those skilled in the art, such as "near-field communication reader" ("NFCreader"), "near-field communication front end" ("NFC front end"). One could also refer to a near-field communication electronic unit, or a near-field communication electronic module, except that the antenna is not part of this unit or module. In addition, the components forming the near-field communication integrated circuit are generally carried by a substrate and in a protective case. This assembly forms an electronic chip so that, for those skilled in the art, the terms "chip" and "integrated circuit" are generally synonymous.The near field communication integrated circuit can therefore also be referred to as a "near field communication chip".

[0050] The figure shows a functional diagram, otherwise called a "block diagram" in English, of a payment terminal 1. It includes a screen 2, a wireless communication module 3, a keyboard 4, and a processing unit 5 comprising a security controller and an application processor.

[0051] The processing unit 5 comprises a module 6 for cryptography and storage of security keys. This processing unit 5 is configured to implement EMV standards, in particular EMV level 1, 2 and 3 standards. The acronym EMV, for “EuropayMastercard Visa”, designates the international security standard for bank card payment methods. This processing unit 5 is connected, by an SPI interface, to a module 13 for interface and processing of radio protocols, belonging to a near-field communication integrated circuit 7.

[0052] The processing unit 5 also comprises a computer-readable recording medium comprising instructions which, when executed by a computer, here by the processing unit 5, cause the latter to implement the steps of the method 100 described below. In other words, the unit 5 comprises, in recorded form, a computer program 21 thus comprising instructions which, when the program is executed by a computer, here by the processing unit 5, cause the latter to implement the steps of the method 100. This program is installed beforehand by loading an application into the terminal 1.

[0053] The Near Field Communication Integrated Circuit 7 is the circuit marketed under the reference PN5190 by the company NXPSemiconductors N.V.

[0054] According to the description provided by its manufacturer, this integrated circuit 7 comprises the elements described below. The circuit is provided with two reception terminals Rx1 and Rx2 to receive two tracks of a near-field communication antenna. To the terminals Rx1 and Rx2 are connected an automatic gain control module 8. This module 8 is connected to a baseband filter 9. This filter 9 is connected to an analog-to-digital converter 10. This converter 10 is connected to a digital signal processor 11. This processor 11 is connected to a contactless communication test module 12. This module 12 is connected to the interface module 13 and radio protocol processing module. The integrated circuit 7 also comprises a DC-DC converter 14, powered by an electrical power supply source external to the circuit 7. This converter 14 powers, within the circuit 7, a transmitter 16, via a voltage regulator 15.This voltage regulator 15, called a "low-drop out voltage regulator" in English, commonly called an "LDO regulator" or "LDO", regulates the voltage to be supplied to the terminals of the transmitter 16. The circuit 7 is also provided with two transmission terminals Tx1 and Tx2 to receive two tracks of a near-field communication antenna. The transmitter 16 is connected to these two terminals. A waveform control module 17 is connected to the transmitter 16.

[0055] Finally, the integrated circuit 7 comprises a dynamic power control unit 18 for regulating the power of a signal transmitted by the transmitter 16 to an antenna. Indeed, a signal emitted by the antenna must comply with certain standards, in particular power standards. These standards are safety standards, such as EMV standards. To ensure compliance with these standards, the unit 18 is configured to check a voltage, called VDDPA by the manufacturer, of the power supply at the terminals of the transmitter 16. Depending on its result, the control unit 18 modifies an intensity value, called ITVDD by the manufacturer, passing through the transmitter 16, so that the power at the terminals of the transmitter 16 complies with the established safety standards. The intensity values ​​of ITVDD and voltage of VDDPA are stored in a register of the unit 18, or associated with the unit 18, and accessible in read mode.

[0056] The payment terminal 1 also includes a near-field communication antenna 19. It has two tracks. Each of these two tracks is connected to an impedance matching circuit 20. The impedance matching circuit 20 connects the antenna 19 to the integrated circuit 7 via the transmission terminals Tx1 and Tx2 on the one hand and via the reception terminals Rx1 and Rx2 on the other hand.

[0057] In normal operation, when a payment device, such as a bank card, is brought close to the antenna 20, contactless communications are performed via NFC technology between the antenna and the device. And the received and transmitted signals are processed by the near-field communication integrated circuit 7.

[0058] We will now describe, with reference to the, the method 1000 for implementing the invention. It is implemented by the processing unit 5, by executing the computer program 21.

[0059] In step 1010, the voltage value VDDPA is determined. It is accessed from the control unit 18.

[0060] In step 1020, the intensity value ITVDD is determined. It is accessed from the control unit 18.

[0061] In step 1030, an operating or malfunctioning state of the antenna is deduced from the voltage value VDDPA and the intensity value ITVDD among the following states:

[0062] - the antenna is connected to the communication integrated circuit;

[0063] - the antenna is disconnected from the communication integrated circuit;

[0064] - an antenna track is disconnected from the communication circuit;

[0065] - two antenna tracks are disconnected from the communication circuit.

[0066] Indeed, it appears that these states are deduced from these values ​​in accordance with the following table.

[0067] Antenna StatusITVDD (mA)VDDPA (V)Antenna Connected2555.7Antenna Disconnected2252.2One Track Cut2552.2Two Tracks Cut2252.2

[0068] Thus, we deduce from these two parameters the precise state of the antenna, that is to say whether it is well connected, whether it is disconnected, or whether it has one or two cut tracks.

[0069] We can also deduce a less precise state of the antenna using only one of these two parameters. Indeed, if the value of ITVDD is 255 mA, we already know that either the antenna is connected, or only one of its tracks is broken. Similarly, if the value of VDDPA is 2.2 V, we know that it has a fault, whether it is a disconnection or a break in one or both of its tracks.

[0070] Step 1040 is the alert of the state of the antenna. Thus, the deduced state of the antenna can be indicated to a user on a screen of the terminal 1. Thus, a user using, on the terminal 1, the application including the program 21, obtains the state of the antenna 19 of this terminal without having to disassemble it and examine each of the components. This is particularly useful in the case where the terminal appears to be malfunctioning. It is also useful in the context of preventive maintenance operations. For example, if a fault is deduced only for one track of the antenna, it may be considered to continue operating the terminal by configuring it appropriately, or on the contrary it may be planned to replace the antenna before the malfunction worsens.

[0071] Illustrates another payment terminal 22. It comprises a near-field communication integrated circuit 23 distinct from the integrated circuit 7 of the terminal 1, and a near-field communication antenna 24.

[0072] Integrated circuit 23 is the circuit marketed under the reference ST25R3916 by the company STMicroelectronics. This circuit 23 is equipped with different connection pins.

[0073] Among them, there are two pins RFO1 and RFO2 for transmitting a signal, and two pins RFI1 and RFI2 for receiving a signal. These four pins are connected to the antenna 24 via an impedance circuit.

[0074] As described by the circuit manufacturer, within the near-field communication integrated circuit 23, an amplitude detector converts a differential back-modulation radio signal received between the two receiving pins RFI1 and RFI2 into a proportional voltage value, called the signal amplitude value. This voltage value is then converted into a digital value and stored in a register of an analog-to-digital converter of the circuit 23, by an eight-bit coded value. The presence of these two terminals instead of a single receiving terminal, and the conversion of the respective signals received at these terminals into an amplitude value, is intended to increase the reliability of near-field communication.

[0075] The circuit 23 is connected to an MCU (for “MicrocontrollerUnit”) of the payment terminal 22. This MCU plays the same role as the processing unit 5 of the terminal 1. Thus, it implements a computer program 25 comprising instructions which, when the program is executed by a computer, here by the MCU, lead the latter to implement the steps of a method 2000. In other words, the MCU comprises, in recorded form, a computer program 25 thus comprising instructions which, when the program is executed by a computer, here by the MCU, lead the latter to implement the steps of the method 2000. This program 25 is installed beforehand by loading an application into the terminal 22.

[0076] In normal operation, when a payment device, such as a bank card, is brought close to the antenna 24, contactless communications are performed via NFC technology between the antenna and the device. And the received and transmitted signals are processed by the near-field communication integrated circuit 23.

[0077] We will now describe, with reference to the, the method 2000 for implementing the invention. It is implemented by the MCU, by executing the computer program 225.

[0078] In step 2010, the value of the signal amplitude is determined. It is accessed from the register of circuit 23 in which it is stored.

[0079] In step 2020, an operating or malfunctioning state of the antenna is deduced from the amplitude value among the following states:

[0080] - the antenna is connected to the communication integrated circuit;

[0081] - the antenna is disconnected from the communication integrated circuit or has at least one cut track.

[0082] Indeed, it appears that these states are deduced from these values ​​in accordance with the following table.

[0083] Antenna StatusAmplitude ValueAntenna Connected155Antenna Disconnected15One Track Cut15Two Tracks Cut15

[0084] Thus, we deduce from this amplitude value the observation that the antenna is connected and has its two functional tracks, or that it has a connection or cut fault.

[0085] Step 2030 is the antenna status alert. The user handling the application associated with program 25 is therefore aware of the antenna status.

[0086] The two implementation modes described have in particular in common the fact of diverting the use of internal values ​​of the near-field communication integrated circuits in order to determine the state of the near-field communication antenna. Indeed, in the first implementation mode 1000, the voltage and intensity values ​​used are normally intended to limit the magnetic field of the antenna to comply with standards. In the second implementation mode 2000, the amplitude value is intended to improve the reliability of transmissions. Determining the state of the antenna by means of these values ​​is therefore an unexpected effect.

[0087] The invention is not limited to the embodiments presented and other embodiments will become apparent to those skilled in the art.

Claims

Method (1000; 2000) for determining a state of a near-field communication antenna (19; 24), implemented by computer within a terminal (1; 22) comprising:- the near-field communication antenna (19; 24),- a near-field communication integrated circuit (7; 23) configured to be connected to the antenna (19; 24),in which the following steps are implemented:- determination (1010, 1020; 2010), within the integrated circuit (7; 23), of at least one voltage or current value,- deduction (1030; 2020), from the voltage or current value determined within the integrated circuit (7; 23), of an operating or malfunctioning state of the antenna (19; 24). Method (1000; 2000) according to the preceding claim, in which the step of determining (1010, 1020; 2010) at least one voltage or current value comprises accessing a register of the integrated circuit in which the value is recorded. Method (1000) according to one of the preceding claims, in which, the near field communication integrated circuit (7) comprising: - a transmitter (16) for transmitting a signal to the antenna (19), - a dynamic power control unit (18) for regulating a power of a signal transmitted by the transmitter (16) to the antenna (19), the step of determining (1010) a value comprises a determination of a voltage across the transmitter (16) and / or a step of determining an intensity flowing through the transmitter (16). Method (1000) according to the preceding claim, wherein the deduction step comprises deducing, from the determined voltage and / or intensity, at least one operating or malfunctioning state of the antenna (19) among the following states: - the antenna (19) is connected to the integrated communication circuit (7); - the antenna (19) is disconnected from the integrated communication circuit (7); - one track of the antenna (19) is disconnected from the communication circuit (7); - two tracks of the antenna (19) are disconnected from the communication circuit (7). The method (2000) of claim 1 or 2, wherein, the communication integrated circuit (23) having two signal receiving pins for connection to the antenna (24), the determining step (2010) comprises determining a signal amplitude value at the two receiving pins. Method (2000) according to the preceding claim, wherein the deduction step (2012) comprises deducing, from the determined differential value, at least one operating or malfunctioning state of the antenna (24) among the following states: - the antenna (24) is connected to the communication integrated circuit (23); - the antenna (24) is disconnected from the communication integrated circuit (23) or at least one cut track. Computer program (21; 25) comprising instructions which, when the program is executed by a computer, cause the latter to implement the steps of the method (1000; 2000) according to any one of the preceding claims. A computer-readable recording medium comprising instructions which, when executed by a computer, cause the computer to implement the steps of the method (1000; 2000) according to one of claims 1 to 6. Terminal (1; 22) comprising:- a near-field communication antenna (19; 24),- a near-field communication integrated circuit (7; 23) configured to be connected to the antenna,- a processor (5; MCU) configured to implement the steps of the method according to any one of claims 1 to 6. Terminal (1; 22) according to the preceding claim, configured to carry out a contactless electronic payment.

Images