Near-field communication method and device

Abstract

Near-field communication method and device. This description relates to an NFC communication method (400) between a first device (401) in card mode, comprising an NFC controller (4012), and a second device (402) in reader mode (402), wherein said first device (401) exits a listening mode upon reception by said NFC controller (4012) of content from a sequence captured from a radio frequency field. Figure for the abbreviation: Fig. 4

Description

Title of the invention: Near-field communication method and device. Technical field

[0001] This description relates generally to electronic circuits and devices, and more particularly to electronic circuits and devices adapted to implement wireless communication. This description relates more specifically to Near Field Communication (NFC) and its implementation. Previous technique

[0002] It is increasingly common to use wireless communications to transmit data between two, or more than two, electronic devices. One type of wireless communication relevant here is near field communication (NFC).

[0003] Increasingly, transactions are being carried out via wireless communications, such as communications using near-field communication technology. The communication protocols implemented during such wireless communications are constantly evolving.

[0004] To implement such NFC communication, a first electronic device can operate in a so-called "card" or "card emulation" mode, and a second can operate in a so-called "reader" or "terminal" mode. Such electronic devices are, for example, smart or advanced mobile phones (smartphones).

[0005] It would be desirable to be able to improve, at least in part, certain aspects of the protection of NFC-type wireless communications between electronic devices. Summary of the invention

[0006] There is a need for improved and faster wireless communications.

[0007] There is a need for improved and faster NFC communications.

[0008] There is a need for electronic devices implementing such communications.

[0009] There is a need for systems comprising at least two electronic devices implementing such communications.

[0010] One embodiment overcomes all or part of the disadvantages of known wireless communications.

[0011] One embodiment overcomes all or part of the drawbacks of known NFC communications.

[0012] An embodiment provides for an NFC communication method between a first device in card mode, comprising an NFC controller, and a second device in reader mode, in which said first device exits a listening mode upon receipt by said NFC controller of content from a sequence captured from a radio frequency field.

[0013] An embodiment provides an electronic device adapted to be a first device in an NFC communication method between said first device in card mode, comprising an NFC controller, and a second device in reader mode, in which said first device outputs from a listening mode upon reception by said NFC controller of content from a sequence captured from a radio frequency field.

[0014] One embodiment provides for an electronic system comprising a first device and a second electronic device, the system being adapted to implement an NFC communication method between said first device in card mode, comprising an NFC controller, and said second device in reader mode, in which said first device exits a listening mode upon receipt by said NFC controller of content in a sequence captured from a radio frequency field.

[0015] According to one embodiment, said sequence is part of an interrogation frame emitted by said second device.

[0016] According to one embodiment, said NFC controller detects the content of said sequence by comparison with one or more reference contents which it stores in memory.

[0017] According to one embodiment, said reference contents stored in memory in the NFC controller are sent to it by an application processor of said first device.

[0018] According to one embodiment, said application processor of said first device is adapted to trigger said listening mode.

[0019] According to one embodiment, upon receipt of said content, the NFC controller is adapted to signal to said application processor a suspension of the listening mode.

[0020] According to one embodiment, said content is at the beginning of a first query frame.

[0021] According to one embodiment, at the end of NFC communication, the NFC controller is adapted to re-enter listening mode after a predefined delay.

[0022] Another embodiment provides for a computer program product comprising program code instructions recorded on a medium usable in a computer, comprising: computer-readable programming means for implementing the process described above when said program is running on a computer. Brief description of the drawings

[0023] These features and advantages, as well as others, will be described in detail in the following description of particular embodiments, given by way of non-limiting example, in relation to the accompanying figures, among which:

[0024] [Fig.1] represents an embodiment of an electronic device adapted to implement NFC communication according to an embodiment;

[0025] [Fig.2] represents an embodiment of an electronic system adapted to implement NFC communication according to an embodiment;

[0026] Figure 3 represents a common method for implementing NFC communication; and

[0027] [Fig.4] represents an implementation method of an NFC communication process. Description of the implementation methods

[0028] The same elements have been designated by the same reference numerals in the different figures. In particular, the structural and / or functional elements common to the different embodiments may have the same reference numerals and may have identical structural, dimensional and material properties.

[0029] For the sake of clarity, only the steps and elements useful for understanding the described embodiments have been shown and are detailed. Unless otherwise specified, when reference is made to two interconnected elements, this means directly connected without any intermediate elements other than conductors, and when reference is made to two coupled elements, this means that these two elements can be connected or linked via one or more other elements.

[0030] In the following description, when reference is made to absolute position qualifiers, such as the terms "front", "back", "top", "bottom", "left", "right", etc., or relative position qualifiers, such as the terms "above", "below", "superior", "inferior", etc., or to orientation qualifiers, such as the terms "horizontal", "vertical", etc., reference is made, unless otherwise specified, to the orientation of the figures.

[0031] Unless otherwise specified, the expressions "approximately", "roughly", and "in the order of" mean within 10%, preferably within 5%.

[0032] The embodiments described below relate to the implementation of wireless communication, and more particularly, the implementation of faster NFC communication. This description applies more specifically to portable devices implementing NFC communication. The focus is more precisely on the card side, that is, the device operating in "card" mode or "card emulation" mode, while other equipment of the The system operates in "reader" mode. This equipment operating in reader mode can be any suitable device, including another phone operating in reader mode. Devices equipped with card emulation mode include smartphones. Such phones can operate in either reader or card mode. Such devices are described in relation to [Fig. 1]. NFC communication and the electronic system implementing it are described in relation to [Fig. 2].

[0033] These embodiments relate to a recent development in NFC communication protocols. In these recent developments, when a wearable device is in card mode (hereafter referred to as the device, device in card mode, card, or card device), it can switch to a listening or observing mode (Observer mode), that is, a mode in which it "listens" to its environment in order to detect a reader emitting a radio frequency field, but in which it is not adapted to respond to stimuli. However, the use of such a listening mode can slow down NFC communication. The operation of such a mode is described in more detail with reference to Figures 2 and 3.

[0034] The solution provided by the embodiments consists of detecting a particular command to automatically exit a listening mode. This solution is described in detail with reference to [Fig. 4].

[0035] The embodiments described below are particularly suited to any electronic device adapted to implement NFC communication in "card" mode, such as a mobile phone, a smartphone, a portable electronic device such as a smartwatch or electronic cigarette.

[0036] Moreover, the embodiments described above are particularly suitable for use in any type of industrial market where NFC communication is used. More specifically, such NFC communication can be intended for: - the automotive industry, for example in the field of automotive electrification or in the field of Advanced Driver Assistance Systems (ADAS); - industry, for example in the field of green energy, infrastructure electrification, the Internet of Things (IoT) and smart homes, where electricity and energy consumption and data exchange are key elements; and - the personal electronics industry, for example in the field of mobile telephony and the Internet of Things (IoT), as well as in the field of broadband interfaces.

[0037] Fig. 1 is a block diagram representing, very schematically, an architecture of an example of an electronic device 100 adapted to implement an NFC communication process.

[0038] The electronic device 100 includes a processor 101 (CPU) adapted to perform various data processing operations on data stored in memories and / or provided by other circuits of the device 100. In one embodiment, the processor 101 is adapted to implement an NFC communication method. In a particular embodiment, the processor 101 is adapted to implement one or more applications themselves adapted to implement NFC communications or transactions; in this case, the processor 101 may be called an application processor.

[0039] The electronic device 100 further comprises different types of memory 102 (MEM), including, for example, non-volatile memory, volatile memory, and / or read-only memory. Each memory 102 is adapted to store different types of data.

[0040] The electronic device 100 further comprises, for example, a secure element 103 (SE) adapted to process sensitive and / or secret data. The secure element 103 may include its own processor(s), its own memory(ies), etc. In one embodiment, the processor 101 is adapted to implement an NFC communication method. In a particular embodiment, the secure element 103 may include a processor adapted to implement one or more applications themselves adapted to implement NFC communications or transactions; in this case, the processor of the secure element 103 may be called an application processor.

[0041] The electronic device 100 may further include interface circuits 104 (IN / OUT) adapted to send and / or receive data from outside the device 100. The interface circuits 104 may further be adapted to implement a data display, for example, a display screen.

[0042] In one embodiment, the electronic device comprises NFC circuits 105 (NFCC). The circuits 105 include an NFC controller adapted to exchange data with one or more other electronic devices during the implementation of NFC communication. In one example, the controller includes components enabling the implementation of NFC communication. In one embodiment, the NFC controller is adapted to receive commands from the processor adapted to implement one or more applications using NFC communication, such as the processor 101 or the secure element 103. The NFC circuits 105 further include circuits adapted to generate and capture a radio frequency electromagnetic field. In one embodiment, the NFC controller includes data storage means.

[0043] The electronic device 100 further comprises various circuits 106 (FCTs) adapted to perform different functions. By way of example, the circuits 106 may include measurement circuits, data conversion circuits, etc.

[0044] The electronic device 100 further includes one or more data buses 107 adapted to transfer data between its different components.

[0045] According to a particular example, the electronic device 100 is adapted to implement computer programs, and in particular a computer program enabling the implementation of a wireless communication process, for example a computer program enabling the implementation of a wireless communication process on the terminal side and / or on the card side.

[0046] More specifically, the electronic device 100 is adapted to implement at least one computer program product comprising program code instructions recorded on a medium usable in a computer, comprising computer-readable programming means for implementing the wireless communication process as a terminal device and / or as a card device when said program is running on a computer.

[0047] Fig. 2 represents, very schematically and in block form, an embodiment of a system 200 implementing NFC communication.

[0048] The system 200 comprises two devices 201 (CARD) and 202 (TERM). Each device 201, 202 is of the type of device 100 described in relation to [Fig. 1].

[0049] Device 201 is a card-type device, that is, an electronic device operating in "card" or "card emulation" mode. Device 201 is hereafter referred to as a card device.

[0050] Device 202 is a reader-type device, that is, an electronic device operating in "reader" or "terminal" mode. Device 202 is hereafter referred to as the reader device.

[0051] According to one embodiment, the device 201 comprises at least one application processor 2011 (APP PROC) and one NFC controller 2012 (NFCC). The application processor 2011 is adapted to implement one or more applications capable of using NFC communication, for example, to implement a transaction (e.g., banking, transportation, access, etc.). The NFC controller 2012 is adapted to implement NFC communication in practice.

[0052] Although not shown in [Fig.2], device 202 also includes at least one NFC controller to implement NFC communication, and, for example, a processor.

[0053] NFC communication uses radio frequency (RF) signals transmitted by the communication devices using antennas of an oscillating / resonant circuit. When the reader device 202 emits an electromagnetic field To initiate communication with the card 201 device, this field is captured by the card 201 device as soon as it is within range. This field is detected by the card 201 device.

[0054] Generally, from a communication protocol perspective, NFC communication begins with the reader sending one or more polling frames. Once this polling frame is received by a card reader, the card reader responds, and NFC communication is initiated. NFC communication then consists of an exchange of data sequences forming requests and responses. There are several types of polling frames, some defined by standards, including A, B, and F type frames. These types of polling frames are defined, for example, by the bytes transmitted in a frame. Other bytes in a frame can define the length of the allowed responses.

[0055] Furthermore, recent developments have led to the creation of a new operating mode for an electronic device adapted to implement NFC communication. This operating mode is a listening mode, or "Observer" mode, during which an electronic device captures data sequences, attempts to interpret the various protocols it receives, and, when it detects a command according to a protocol it can handle, configures itself to that protocol so that the reader device can initiate a transaction. When a card device operates in such a mode, its NFC controller is adapted to receive, capture, or listen to any interrogation frames emitted by a reader device within whose range it may be located. [Fig. 3] illustrates the beginning of a typical NFC communication in more detail, and illustrates, in particular, the operation of the listening mode. [Fig.[4] illustrates, for its part, the beginning of a method of implementing an NFC communication process in more detail, and illustrates, in particular, the operation of the listening mode.

[0056] Fig. 3 represents, very schematically, a method of implementing an NFC 300 communication process within an electronic system of the type of system 200 described in relation to Fig. 2.

[0057] More specifically, NFC 300 communication is implemented between a reader device 302 of the type of the reader device 202 described in relation to [Fig. 2], and a card device 301 of the type of the device 201 described in relation to [Fig. 2]. The card device 301 comprises an application processor 3011 of the type of the processor 2011 described in relation to [Fig. 2] and an NFC controller 3012 of the type of the NFC controller 2012 described in relation to [Fig. 2]. [Fig. 3] shows the data exchanges between the reader device 302, the application processor 3011, and the NFC controller 3012.

[0058] Initially, no communication has been initiated between the card device 301 and the reader device 302. The card device 301 is therefore waiting for a prompt to establish NFC communication. The card device 301 can thus enter a listening mode. More specifically, the card device 301 can put its NFC controller into a listening mode. To do this, the application processor 3011 activates the listening mode of the NFC controller 3012 by sending it a command, or request, En_Obs_Mode300. The NFC controller 3012 receives this command, enters listening mode, and can, for example, respond to the application processor 3011 with an Ok_Obs_Mode_EN_300 confirmation. When in this listening mode, the NFC controller 3012 begins to "listen" for a possible field emitted by the reader device 302.

[0059] As soon as the NFC controller 3012 receives a field emitted by the reader device 302 and receives commands and requests, it transmits them directly to the application processor 3011 without responding, and, for example, without analyzing them. When in this listening mode, the NFC controller 3012 is not authorized to send data.

[0060] In the example in [Fig. 3], the reader device 302 sends several query frames comprising several requests and commands labeled NFC-A-300-CCmd, NFC-A-300-Reql, NFC-B-300-Req2, and NFC-F-300-Cmd. For example, if the reader device 302 is adapted to implement NFC communication using several different communication protocols, it can send query frames according to the different protocols it supports. All these requests and commands, labeled NFC-A-300-CCmd, NFC-A-300-Reql, NFC-B-300-Req2 and NFC-F-300-Cmd, are received by the NFC controller 3012 and are therefore transmitted directly to the application processor 3011. The application processor 3011 then analyzes the content of these requests and commands, labeled NFC-A-300-CCmd, NFC-A-300-Reql, NFC-B-300-Req2 and NFC-F-300-Cmd, and decides whether or not to establish communication with the reader device 302.

[0061] If the application processor 3011 decides to communicate with the reader device 302, it sends a command, or request, Dis_Obs_Mode300 to the NFC controller to exit listening mode. The NFC controller 3012 receives this command, exits listening mode, and can, for example, respond to the application processor 3011 with an Ok_Obs_Mode_Dis_300 acknowledgment. According to one variant, the NFC controller 3012 can be exited from listening mode by a processor other than the application processor 3011.

[0062] According to example, the listening mode, or observer mode, is an operating mode of the NFC controller present in electronic devices incorporating the operating system known as "Android".

[0063] Once the NFC controller 3012 is in a normal operating mode, that is to say an operating mode in which it can implement NFC communication, it can respond to the terminal device 302 when it receives commands and requests from it.

[0064] In the example in [Fig. 3], the reader device 302 sends an NFC-A-300-Req request and the NFC controller 3012 responds with an NFC-A-300-Rsp response. In one example, the NFC controller 3012 can respond directly, or it can consult the application processor 3011 to determine which response to send to the reader device 302. In another example, the application processor 3011 can select, based on the type of protocol used by the reader device 302 and / or based on the content of the query frame(s) sent by the reader device 302, the application implementing the NFC communication and allow that application to produce a response for the reader device 302.

[0065] One drawback of the NFC 300 communication method is that using the listen mode slows down NFC communication, and in particular delays the establishment of NFC communication. The implementation described in relation to [Fig. 4] aims to overcome this problem.

[0066] Fig. 4 represents, very schematically, a method of implementing an NFC 400 communication process within an electronic system of the type of system 200 described in relation to Fig. 2.

[0067] More specifically, NFC 400 communication is implemented between a reader device 402 of the type of the reader device 202 described in relation to [Fig. 2], and a card device 401 of the type of the device 201 described in relation to [Fig. 2]. The card device 401 comprises an application processor 4011 of the type of the processor 2011 described in relation to [Fig. 2] and an NFC controller 4012 of the type of the NFC controller 2012 described in relation to [Fig. 2]. In [Fig. 4], the data exchanges between the reader device 402, the application processor 4011, and the NFC controller 4012 are shown.

[0068] The embodiments described here allow the card device 401 to exit listening mode, or Observer mode, based on the recognition of content in a sequence emitted by the reader device 402 and recognized by the NFC controller 4012 of the card device 401. Thus, the application processor 4011 does not need to analyze all the protocols.

[0069] Thus, a preparation step, or initialization step, is first implemented. The application processor 4011 sends the NFC controller 4012 a list of reference contents for a data sequence, command, or request, which can be recognized as signals to stop the listening mode. In the example in [Fig. 4], the application processor 4011 sends a command Set_Obs_Mode_ExF400 includes said list of reference contents. For example, these contents are part of NFC communication protocol query frames.

[0070] Herein, the content of a data sequence, command or query is defined as a piece of data or a group of data included in a data sequence, command or query.

[0071] According to a first embodiment, the reference content list can be a complete data list, i.e., bit or byte strings, integers, and / or complete data sets. For example, each content item can have a defined length and be located at any position in a data sequence or data frame. Alternatively, each content item can have an undefined length and be located at any position in a data sequence or data frame.

[0072] According to a particular example, the Set_Obs_Mode_ExF400 command can include, for example, different information including: - a list of reference content each characterized by a type, a length and a value; - a timeout value to restore listening mode; and - a value representing a number of data sequences following a reference content.

[0073] According to a second embodiment, the list of reference contents can be a list of data masks. A mask can be a data part, for example a prefix of a data element, or a set of data parts.

[0074] This preparation step can be done at any time during the life of the NFC 4012 controller, and, more specifically, this list can be updated by adding or removing content at any time during the life of the NFC 4012 controller.

[0075] In a state prior to NFC communication, the card device 401 is therefore waiting for a prompt to initiate NFC communication. The card device 401 can thus enter a listening mode. More specifically, the card device 401 can put its NFC controller into a listening mode. To do this, the application processor 4011 activates the listening mode of the NFC controller 4012 by sending it a command, or request, En_Obs_Mode400. The NFC controller 4012 receives this command, enters listening mode, and can, for example, respond to the application processor 4011 with an Ok_Obs_Mode_EN_400 confirmation. When in this listening mode, the NFC controller 4012 is configured to listen for any field emitted by the reader device 302 and not to respond.

[0076] The reader device 402 generates a radio frequency field to attempt to communicate with a card device. The NFC controller 4012 detects this field. As an example, the NFC 4012 controller can indicate to the 4011 application processor that it is capturing a field by sending it an RF_Field_NTF400_ON notification.

[0077] The reader device 402 sends one or more query frames corresponding to one or more different communication protocols while awaiting a response. In [Fig. 4], the reader device 402 sends at least one query frame whose communication protocol is compatible with the card device 401. More specifically, the reader device 402 begins by sending at least one NFC-A-400-CCmd data sequence whose content is part of the list stored in the NFC controller 4012.

[0078] Upon receiving the NFC-A-400-CCmd data sequence, the NFC controller 4012 detects the content and automatically suspends from listening mode. For example, the NFC controller 4012 can inform the application processor 4011 that it has suspended from listening mode by sending an Obs_Mode_Susp400 notification.

[0079] According to a particular example, the Obs_Mode_Susp400 command can include, for example, various pieces of information including: - a value indicating the type of the Obs_Mode_Susp400 command; - a length value for the Obs_Mode_Susp400 command; and - a value indicating the received content that triggered the sending of the Obs_Mode_Susp400 command.

[0080] Once the NFC controller 3012 has suspended listening mode and is in normal operating mode, that is, an operating mode in which it can implement NFC communication, it can respond to the terminal device 302 when it receives commands and requests from it. For example, the reader device 402 sends a command, or request, NFC-A-400-Cmdl or NFC-A-400-Cmd2, to which the NFC controller responds with an NFC-A-400-Rspl or NFC-A-400-Rsp2 reply. The NFC controller 4012 can also indicate to the application processor 4011 that NFC communication is in progress with the reader device 402, for example, by sending an RF_Field_ACT400 notification. As an example, the NFC 4012 controller could also send response waiting requests to the reader device when it needs to query the application processor 4011 before responding to the reader device 402.

[0081] The continuation of the NFC communication can, for example, take place by including the application processor 4011. This can, for example, select an application and let that application implement the NFC communication with the NFC controller 4012.

[0082] Once the NFC communication has been successfully completed, the reader device 402 stops its radio frequency field. For example, the NFC controller 4012 can indicate to the application processor 4011 that it is no longer detecting any fields by sending it An RF_Field_NTF400_OFF notification. The NFC controller can also, as an example, re-enter, or return to, listening mode. As an example, the NFC controller can indicate this to the 4011 application processor by sending it a Res_Obs_Mode400 notification.

[0083] According to a particular example, the Obs_Mode_Susp400 command may include, for example, an empty data field.

[0084] According to one variant, the NFC controller 4012 can wait a predefined delay after receiving an NFC sequence and resume listening mode if it does not receive any further sequences from the reader device 402. According to one example, this predefined delay can be zero.

[0085] One advantage provided by the embodiments of [Fig.4] is that they make it possible to avoid waiting for the analysis of query frames by the application processor to start an NFC communication, and therefore to save time on the establishment of the NFC communication.

[0086] Another advantage of these embodiments is backward compatibility with existing devices, provided that it is possible to update their internal program(s). Indeed, no changes are required on the part of the readers.

[0087] Various embodiments and variations have been described. A person skilled in the art will understand that certain features of these various embodiments and variations could be combined, and other variations will become apparent to a person skilled in the art.

[0088] Among the possible variants, we will note: - the possibility of responding to a so-called "proprietary" framework to exit listening mode; - a hardware or hardware and software implementation on the device card side (requiring a structural modification).

[0089] Moreover, although the "Android" device has been taken as an example, the solutions described apply and can be transposed to any other system in which similar problems arise.

[0090] Finally, the practical implementation of the embodiments and variants described is within the reach of a person skilled in the art, based on the functional indications given above.

Claims

Demands

1. NFC communication method (400) between a first device (401) in card mode, comprising an NFC controller (4012), and a second device (402) in reader mode (402), wherein said first device (401) exits a listening mode upon reception by said NFC controller (4012) of content from a sequence captured from a radio frequency field.

2. Electronic device adapted to be a first device (401) in an NFC communication method between said first device (401) in card mode, comprising an NFC controller (4012), and a second device (402) in reader mode, in which said first device (401) outputs from a listening mode upon reception by said NFC controller (4012) a content of a sequence captured from a radio frequency field.

3. Electronic system comprising a first device (401) and a second electronic device (402), the system being adapted to implement an NFC communication method between said first device (401) in card mode, comprising an NFC controller (4012), and said second device (402) in reader mode, in which said first device (401) exits a listening mode upon reception by said NFC controller (4012) of content in a sequence captured from a radio frequency field.

4. Method according to claim 1, device according to claim 2, or system according to claim 3, wherein said sequence is part of an interrogation frame emitted by said second device (402).

5. Method according to claim 1 or 4, device according to claim 2 or 4, or system according to claim 3 or 4, wherein said NFC controller (4012) detects the content of said sequence by comparison with one or more reference contents which it stores in memory.

6. Method according to any one of claims 1, 4 or 5, device according to any one of claims 2, 4 or 5, or system according to any one of claims 3 to 5, wherein said reference contents stored in memory in the NFC controller (4012) are sent to it by an application processor (4011) of said first device (401).

7. Method, device or system according to claim 6, wherein said application processor (4011) of said first device (401) is adapted to trigger said listening mode.

8. Method, device or system according to claim 6 or 7, wherein, upon receipt of said content, the NFC controller (4012) is adapted to signal to said application processor (4011) a suspension of listening mode.

9. A method according to any one of claims 1, 4 to 8, a device according to any one of claims 2, 4 to 8, or a system according to any one of claims 3 to 8, wherein said content is at the beginning of a first query frame.

10. A method according to any one of claims 1, 4 to 9, a device according to any one of claims 2, 4 to 9, or a system according to any one of claims 3 to 9, wherein, at the end of NFC communication, the NFC controller (4012) is adapted to re-enter listening mode after a predefined delay.

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