HK1179775B - Systems and methods for providing nfc secure application support in battery-off mode - Google Patents

Abstract

The present invention is directed to systems and methods for providing NFC secure application support in battery-off mode. Embodiments of the present invention provide systems and methods for NFC secure application support when an NFC device is executing in a battery-off or battery-low mode. In such a case, the NFC device may have enough power to execute some applications (e.g., read-only applications) but not enough power to execute others (e.g., applications that require data to be written). Embodiments of the present invention enable these lower-power applications to be executed by the NFC device even when a host communications device has no battery power.

Description

System and method for providing NFC secure application support in battery off mode

Technical Field

The present invention relates to Near Field Communication (NFC), and more particularly, to a system and method for providing NFC application support in a battery-off mode.

Background

Near Field Communication (NFC) devices are being integrated into communication devices, such as mobile devices, to facilitate their use in conducting daily transactions. For example, a user of an NFC device may use the NFC device to store credit information provided by a credit card, thereby eliminating the need to carry a large number of credit cards. To provide access to the credit information, a user of the NFC device taps the NFC device to a credit card terminal to transfer credit information to the terminal. Another example of an NFC device application is ticket writing systems such as those used in bus and train terminals. Fare information can be written onto the NFC device without providing the passenger with a ticket. The passenger then taps the NFC device to the reader to take a bus or train without having to use a paper ticket.

Generally, NFC requires that NFC devices exist within a relatively small distance from each other so that their respective magnetic fields can exchange information. Typically, the first NFC device transmits or generates a magnetic field that is modulated with information, such as credit information or fare information. The magnetic field inductively couples information to a second NFC device in proximity to the first NFC device. The second NFC device may respond to the first NFC device by inductively coupling its respective information onto the first NFC device.

In certain circumstances, an NFC device may have to derive power from the magnetic field of another NFC device. Generally, NFC devices may support a variety of applications, such as interfacing with memory to access credit information and/or fare information. Some of these applications, such as reading credit information and/or fare information from memory, require relatively small amounts of power and can be supported using this harvested energy. However, other applications that require relatively large amounts of power, such as writing credit information and/or fare information to memory, cannot be supported using such harvested energy. What is needed is a system and method for determining which applications can be supported using harvested energy.

Disclosure of Invention

The present invention provides an NFC device, comprising: a power acquisition module; a memory storing a list of application identifiers; and a controller, wherein the controller is configured to: the method includes receiving an application identifier request from a reader device, accessing a list of application identifiers, determining whether an amount of power available to the NFC device (amount of power) is sufficient to execute an application of the corresponding application identifier by accessing information in the list of application identifiers, and transmitting the application identifier in response to determining that the amount of power available to the NFC device is sufficient to execute the application.

In the above NFC device, the controller is further configured to determine whether a host communication device coupled to the NFC device has little or no battery power.

In the above NFC apparatus, the application identifier list includes a field indicating whether or not the application corresponding to the application identifier can be executed in the low power mode.

In the above NFC apparatus, the application identifier list corresponds to a plurality of applications, and wherein the controller apparatus is further configured to: determining which applications the NFC device has sufficient power to execute; and transmitting a list of supported application identifiers for applications that the corresponding NFC device has sufficient power to execute.

In the above NFC apparatus, the controller apparatus is further configured to: receiving a request from the reader device to execute a supported application corresponding to one of the supported application identifiers; and in response to the request, providing power to a secure device storing the support application.

The above-mentioned NFC apparatus further includes a one-time programmable (OTP) memory, and in the NFC apparatus, the controller is further configured to: it is determined whether an application corresponding to the application identifier is stored on the OTP memory.

The present invention provides a communication apparatus, comprising: a battery; and an NFC device, wherein the NFC device is configured to: the method includes checking a power level of a battery to determine a power mode, receiving an application identifier request from a reader device, accessing a list of application identifiers, determining whether an amount of power available in the power mode is sufficient to execute an application of a corresponding application identifier by accessing information in the list of application identifiers, and transmitting the application identifier in response to a determination that the amount of power available in the power mode is sufficient to execute the application.

In the above communication apparatus, the application identifier list includes a field indicating whether or not the application corresponding to the application identifier can be executed in the low power mode.

The communication device further includes an Electrically Erasable Programmable Read Only Memory (EEPROM) of the non-volatile (NV) flash memory, and in the communication device, the NFC device is further configured to determine whether an application corresponding to the application identifier is stored on the EEPROM.

The communication device further comprises a security device for storing an application corresponding to the application identifier.

In the above communication device, the communication device is configured to determine whether the NFC device has sufficient power to power the security device.

The above communication device further includes: a plurality of security devices storing a plurality of applications, each application corresponding to one of a plurality of application identifiers, and in the communication device, the communication device further configured to: determining which applications the NFC device has sufficient power to execute; and transmitting a list of supported application identifiers for applications that the corresponding NFC device has sufficient power to execute.

In the above communication apparatus, the NFC apparatus is further configured to: receiving a request from the reader device to execute a supported application corresponding to one of the supported application identifiers; and supplying power to a secure device of the plurality of secure devices storing the support application.

In the above communication device, the communication device is configured to support a plurality of power modes, and wherein a power mode of the plurality of power modes indicates that the NFC device has sufficient power to execute an application stored in a one-time programmable (OTP) memory of the NFC device.

The present invention provides a method comprising: determining a power mode of the NFC device; receiving an application identifier request from a reader device; accessing a list of application identifiers; based on the information in the list of application identifiers, it is determined whether an amount of power available in the power mode is sufficient to execute the application of the corresponding application identifier, and the application identifier is transmitted in response to a determination that the amount of power available in the power mode is sufficient to execute the application.

The method further comprises the following steps: before sending the application identifier, it is determined whether the application corresponding to the application identifier needs to write data to the memory.

In the above method, the power mode is a battery-off mode, which means that the host communication device has little or no battery power.

In the above method, the application identifier list includes a field indicating whether the application corresponding to the application identifier can be executed in the power mode.

In the above method, the field indicates the minimum amount of power required by the application to execute the application.

In the above method, the power mode is one of a plurality of power modes, and wherein the field is a multi-bit field representing the power mode.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with a general description given above and the detailed description of the embodiments given below, serve to explain the principles of the invention. In the drawings:

fig. 1 shows a block diagram of a Near Field Communication (NFC) environment according to an embodiment of the invention.

Fig. 2 shows a block diagram of an NFC device implemented as part of an NFC environment according to an embodiment of the invention.

Fig. 3A shows a block diagram of an NFC device integrated into a communication device.

Fig. 3B shows a block diagram of an NFC device integrated into a communication device incorporating a separate non-volatile memory.

Fig. 4A is a diagram illustrating an exemplary Application Identifier (AID) table.

Fig. 4B is a diagram illustrating an exemplary application identifier AID table incorporating a battery shutdown pattern field according to an embodiment of the present invention.

Fig. 4C is a diagram illustrating an exemplary application identifier AID table that incorporates a power field and a location field, according to an embodiment of the invention.

Fig. 5 is a flowchart illustrating a method of providing NFC secure application support in a battery-off mode according to an embodiment of the present invention.

The features and advantages of the present invention will become more apparent from the detailed description set forth below when taken in conjunction with the drawings, in which like reference characters identify corresponding elements throughout. In the drawings, like reference numbers generally indicate identical, functionally similar, or structurally similar elements. The drawing in which an element first appears is indicated by the leftmost digit(s) in the corresponding reference number.

Detailed Description

In the following description, numerous specific details are set forth to provide a thorough understanding of the present invention. It will be apparent, however, to one skilled in the art that the present invention, including structures, systems and methods, may be practiced without these specific details. The descriptions and representations herein are the ones used by those skilled in the art to most effectively convey the substance of their work to others skilled in the art. In other instances, well-known methods, procedures, components, and circuits have not been described in detail as not to unnecessarily obscure aspects of the present invention.

References in the specification to "one embodiment," "an example embodiment," etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to effect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

Although the description of the present invention is made in terms of NFC, a person skilled in the relevant art will recognize that the present invention is applicable to other communications using near fields and/or far fields without departing from the spirit and scope of the present invention. For example, although the present invention is described using NFC enabled communication devices, one skilled in the relevant art will recognize that the functionality of these NFC enabled communication devices may be adapted to other communication devices using the near field and/or the far field without departing from the spirit and scope of the present invention.

1. Overview

Embodiments of the present invention provide systems and methods for Near Field Communication (NFC) secure application support when an NFC device is executing in a battery-off or low-battery mode. In this case, the NFC device may have sufficient power to execute some applications (e.g., read-only applications), but not enough power to execute other applications (e.g., write-only or read/write applications). Embodiments of the present invention enable these low power applications to be executed by NFC devices even when the host communication device is out of battery power.

NFC communication

2.1NFC communications Environment

Fig. 1 shows a block diagram of an NFC environment according to an embodiment of the invention. The NFC environment 100 enables information, such as one or more instructions and/or data, to be wirelessly communicated between a first NFC device 102 and a second NFC device 104 that are sufficiently close to each other. The NFC device 102 and/or the NFC device 104 may be implemented as separate or discrete devices or may be incorporated into or connected to another electronic or host device such as a mobile phone, portable computing device, other computing device such as a personal computer, laptop or desktop computer, computer peripheral such as a printer, portable audio and/or video player, payment system, ticket writing system such as a parking lot ticketing system, bus ticketing system, train ticketing system or admission ticketing system, ticket reading system, toy, game, poster, packaging, advertising material, product inventory checking system, and/or any other suitable electronic device that would be apparent to one of ordinary skill in the relevant art without departing from the spirit and scope of the present invention. Or the NFC device itself.

The first NFC device 102 and/or the second NFC device 104 interact with each other in a point-to-point (P2P) communication mode or a reader/writer (R/W) communication mode to exchange information, such as one or more instructions and/or data. In the P2P communication mode, the first NFC device 102 and the second NFC device 104 may be configured to operate according to an active communication mode and/or a passive communication mode. The first NFC device 102 modulates its respective information onto a first carrier wave (referred to as modulated information communication) and generates a first magnetic field by applying the modulated information communication to a first antenna to provide a first information communication 152. In the active communication mode, the first NFC device 102 stops generating the first magnetic field after transmitting its respective information to the second NFC device 104. Alternatively, in the passive communication mode, the first NFC device 102 continues to apply the first carrier wave without its corresponding information (referred to as non-modulated information communication), thereby continuing to provide the first information communication 152 once the information has been transferred to the second NFC device 104.

The first NFC device 102 is in sufficient proximity to the second NFC device 104 such that the first information communication 152 is inductively coupled to the second antenna of the second NFC device 104. The second NFC device 104 demodulates the first information communication 152 to recover the information. In the active communication mode, the second NFC device 104 may respond to the information, modulate its corresponding information onto a second carrier, and generate a second magnetic field by applying the modulated information communication to a second antenna to provide a second modulated information communication 154. Alternatively, in the passive communication mode, the second NFC device 104 may respond to the information by modulating the second antenna with its corresponding information, thereby modulating the first carrier to provide the second modulated information communication 154.

In the R/W communication mode, the first NFC device 102 is configured to operate in an initiator or reader mode of operation and the second NFC device 104 is configured to operate in a target or tag mode of operation. However, this example is not limiting, and one skilled in the relevant art will recognize that, in accordance with the teachings herein, the first NFC device 102 may be configured to operate in a tag mode and the second NFC device 104 may be configured to operate in a reader mode without departing from the spirit and scope of the present invention. The first NFC device 102 modulates its respective information onto a first carrier and generates a first magnetic field by applying the modulated information communication to a first antenna to provide a first information communication 152. The first NFC device 102 continues to apply the first carrier wave without its corresponding information so that the first communication of information 152 continues to be provided once the information has been transferred to the second NFC device 104. The first NFC device 102 is in sufficient proximity to the second NFC device 104 such that the first information communication 152 is inductively coupled to the second antenna of the second NFC device 104.

The second NFC device 104 obtains or obtains power from the first information communication 152 to recover, process, and/or provide a response to the information. The second NFC device 104 demodulates the first information communication 152 to recover and/or process the information. The second NFC device 104 may respond to the information by modulating the second antenna with its corresponding information, thereby modulating the first carrier to provide the second modulated information communication.

International standard ISO/IE 18092:2004(E) "Information Technology-intersystem Telecommunications and Information Exchange-Near Field Communication-Interface and Protocol (cip-1)" published on 4/1 and international standard ISO/IE 21481:2005(E) "Information Technology-intersystem Telecommunications and Information Exchange-Near Field Communication-Interface and Protocol-2 (Information Technology-telecommunication and Information Exchange-Near Field Communication-Interface and Protocol-2)", each of which is incorporated herein by reference in its entirety, and international standard ISO/IE 18092:2004(E) "published on 1/15/2005 describe the operation of the first NFC device 102 and/or the second NFC device 104.

2.2NFC device

Fig. 2 shows a block diagram of an NFC device implemented as part of an NFC environment according to an exemplary embodiment of the invention. The NFC device 200 (e.g., NFC device 102 or 104) is configured to operate in a reader mode of operation to initiate an exchange of information, such as data providing some instances and/or one or more instructions, with other NFC devices or to operate in a target or tag mode of operation in response to a request to exchange information with another NFC enabled device. NFC device 200 may be configured as a reader that operates in only a reader mode of operation, a tag that operates in only a tag mode of operation, or a communicator that operates in both a reader mode of operation and a tag mode of operation. NFC device 200 includes a controller module 202, a modulator module 204, an antenna module 206, a demodulator module 208, and an optional power harvesting module 210. The NFC device 200 may represent an exemplary embodiment of the first NFC device 102 and/or the second NFC device 104.

The controller module 202 controls the overall operation and/or configuration of the NFC device 200. The controller module 202 receives the information 250 from one or more data storage devices, such as one or more contactless transponders, one or more contactless tags, one or more contactless smart cards, any other machine-readable medium that would be apparent to a person skilled in the relevant art without departing from the spirit and scope of the present invention, or any combination thereof. Other machine-readable media may include, but are not limited to, Read Only Memory (ROM), Random Access Memory (RAM), magnetic disk storage media, optical storage media, flash memory devices, electrical, optical, acoustical or other form of propagated signals, such as carrier waves, infrared signals, or digital signals, to provide some examples. The controller module 202 may also receive information 250 from a user interface, such as a touch screen display, alphanumeric keypad, microphone, mouse, speaker, any other suitable user interface that would be apparent to one skilled in the relevant art without departing from the spirit and scope of the present invention. The controller module 202 may also receive information 250 from other electronic devices or host devices connected to the NFC device 200.

In general, the controller module provides information 250 as transmission information 252 for transmission to another NFC enabled device. However, the controller module 202 may also use the information 250 to control the overall operation and/or configuration of the NFC device 200. For example, the controller module 202 may optionally issue and/or execute one or more instructions based on the data to control the operation of the NFC device 200 and other NFC enabled devices, such as transmission power, transmission data rate, transmission frequency, modulation scheme, bit and/or byte encoding scheme of the other NFC enabled devices, and/or any other suitable operating parameters that will be apparent to one skilled in the relevant art without departing from the spirit and scope of the present invention.

In addition, controller module 202 may format information 250 into frames of information and may perform error coding (such as a Cyclic Redundancy Check (CRC) to provide an instance) on the frames of information to provide transmission information 252. The information frames may include frame separators to indicate the beginning and/or end of each information frame. The controller module 202 may additionally configure a plurality of frames of information to form a sequence of frames of information for synchronizing and/or calibrating the NFC device 200 and/or another NFC enabled device. The sequence may include sequence separators to indicate the beginning and/or end of each sequence.

In addition, the controller module 202 may perform other functions, such as international standard ISO/IE 18092:2004(E) "Information Technology-intersystem Telecommunications and Information Exchange-Near Field Communication-Interface and Protocol (NFCIP-1)" published on 4/1 2004, and international standard ISO/IE 21481:2005(E) "Information Technology-intersystem Telecommunications and Information Exchange-Near Field Communication-Interface and Protocol-2 (Information Technology-Telecommunications and Information Exchange-Near Field Communication-Interface and Protocol-2)" (NFCIP-2) ", each of which is incorporated herein by reference in its entirety.

Modulator module 204 modulates transmission information 252 onto a carrier wave (such as a radio frequency carrier wave having a frequency of about 13.56MHz to provide an example) using any suitable analog or digital modulation technique to provide modulated information communication as transmission information 254. Suitable analog or digital modulation techniques may include Amplitude Modulation (AM), Frequency Modulation (FM), Phase Modulation (PM), Phase Shift Keying (PSK), Frequency Shift Keying (FSK), Amplitude Shift Keying (ASK), Quadrature Amplitude Modulation (QAM), and/or any other suitable modulation technique that will be apparent to one skilled in the relevant art. Modulation module 204 may continue to provide a carrier wave to provide communication of non-modulated information as transmission information 254 once transmission information 252 has been transmitted to another NFC enabled device. Alternatively, the modulator module 204 may stop providing the transmission information 254 once the transmission information 252 has been transferred to another NFC enabled device.

The antenna module 206 applies the transmission information 254 to an inductive coupling element (such as a resonant tuned circuit) to generate a magnetic field to provide a transmission information communication 256. Additionally, another NFC enabled device may inductively couple the received communication signal 258 to the inductive coupling element to provide a recovered communication signal 260. For example, this other NFC enabled device may respond to the information by modulating its respective antenna with its respective information, thereby modulating the carrier wave to provide the received communication signal 258. As another example, this other NFC-enabled device may modulate its respective information onto its respective carrier and generate its respective magnetic field by applying the modulated information communication to its respective antenna to provide the received communication signal 258.

The power acquisition module 210 acquires power from the received communication signal. Generally, the power harvesting module 210 is implemented when the NFC device 200 is configured as a reader or communicator. In one embodiment, the power drawn includes sufficient power to operate the controller 202, modulator 204, antenna module 206, and/or demodulator 208. Additionally, the power harvesting module may provide sufficient power to operate one or more other components of the host communication device. According to some embodiments of the present invention, the power harvesting module may also provide sufficient power to charge a battery coupled to the NFC device and/or the host communication device.

Demodulator module 208 demodulates recovered communication signal 260 using any suitable analog or digital modulation technique to provide received information 262. Suitable analog or digital modulation techniques may include Amplitude Modulation (AM), Frequency Modulation (FM), Phase Modulation (PM), Phase Shift Keying (PSK), Frequency Shift Keying (FSK), Amplitude Shift Keying (ASK), Quadrature Amplitude Modulation (QAM), and/or any other suitable modulation technique that will be apparent to one skilled in the relevant art.

Typically, the controller module provides the received information 262 as recovery information 266 to a data store, user interface, and/or other electronic or host device. However, the controller module 202 may also use the reception information 262 to control the overall operation and/or configuration of the NFC device 200. Receive information 262 may include more than one instruction and/or data. The controller module 202 may issue and/or execute one or more instructions to control the overall operation and/or configuration of the NFC device 200. For example, the controller module 202 may issue and/or execute one or more instructions based on the data as appropriate to control the operation of the NFC device 200 and other NFC enabled devices, such as the transmission power, transmission data rate, transmission frequency, modulation scheme, bit and/or byte encoding scheme of the other NFC enabled devices, and/or any other suitable operating parameters that will be apparent to one skilled in the relevant art without departing from the spirit and scope of the present invention.

In addition, controller module 202 formats received information 262 into a suitable format for transmission to a data store, user interface, and/or other electronic or host device, and may perform error decoding, such as Cyclic Redundancy Check (CRC) decoding to provide some examples, on received information 262 to provide recovered information 266.

2.3NFC device integration to host device

An NFC device, such as NFC device 200, may be integrated into a host communication device, such as a host mobile phone. Fig. 3A shows a block diagram illustrating an exemplary integration of an NFC device 200 into an electronic host communication device 300 with a shared memory 304 according to an embodiment of the invention. In one embodiment, electronic communication device 300 includes NFC device 200, memory 304, security component 308, WI-FI component 310, phone component 312, bluetooth component 314, battery 316 for powering the communication device, host processor 318, and bus 320. It should be understood that components 312, 318, 310, 308, and 314 are optional and are provided to illustrate components that may be incorporated into a host communication device. It should also be understood that one, some, or all of the components 312, 318, 310, 308, and 314 may be incorporated into the host communication device 300, or may not be incorporated into the host communication device 300 at all, according to embodiments of the present invention.

According to embodiments of the present invention, host communication device 300 may represent a number of electronic communication devices including, but not limited to, a mobile phone, a portable computing device, other computing devices (such as a personal computer, a laptop computer, or a desktop computer), computer peripherals (such as a printer), a portable audio and/or video player, a payment system, a ticket writing system (such as a parking lot ticketing system, a public transportation ticketing system, a train ticketing system, or an admission ticketing system).

3. System for providing NFC secure application support in battery off mode

In one embodiment, the NFC device (e.g., NFC device 102, 104, and/or 200) and/or the NFC controller (e.g., NFC controller 202) are designed to include a secure element that uses a secure external memory. In one embodiment, the secure external memory is provided by a host mobile device (e.g., memory 304). In another embodiment, the secure external memory is provided by a dedicated additional non-volatile memory chip (such as flash memory or EE memory). Utilizing the external memory enables the NFC device and/or the NFC controller to be manufactured using 40nm process technology that does not necessarily support non-volatile memory.

However, using external memory has some drawbacks. For example, when a host device (e.g., electronic communication device 300) is operating in a battery-off mode (or low battery mode), the NFC device 200 (e.g., using the power harvesting module 210) may not be able to harvest enough energy to power the host device and the NFC device circuitry. This is particularly true if the NFC device uses a small antenna (e.g., antenna module 206).

One solution to this problem is to use a separate non-volatile memory that is not shared by the host device. Fig. 3B shows the integration of the separate non-volatile (NV) memory 322. As previously discussed, the separate NV memory 322 may be flash memory or EE memory, and in one embodiment, the separate NV memory 322 is secure memory. For example, data stored in the separate NV memory 322 is protected by encryption when in an unsecured device (e.g., host communication device 300). Thus, the NFC device 200 can use the power harvesting module 210 to harvest energy and access memory from the separate NV memory 322 without having to power all other components of the host communication device 300. It should be appreciated that although FIG. 3B shows a single NV memory 322, embodiments of the present invention incorporate multiple separate NV memories.

However, many NFC device applications require relatively high write currents, which in many cases prevents changing (i.e., writing) the security data in the battery-off mode. Thus, in some embodiments, the NFC device 200 cannot draw enough energy to support these very high write currents even if a separate NV memory 322 is used instead of the host memory 304.

Some NFC device applications do not need to write data. For example, the access control card includes information that is read from the NFC device rather than written to the NFC device. Thus, the access control card function may be supported by the NFC device in a battery-off mode or a low battery mode because the NFC device sending the access control card information does not have to draw enough energy to support the higher write current. Furthermore, in some cases, encryption of the secure memory block may be protected by OTP (one time programmable) memory within the security controller (for counting each change of secure memory), and this type of memory may also require a greater amount of energy to program if the associated NV memory needs to be modified.

Embodiments of the present invention provide systems and methods for controlling a secure application of an NFC device to enable the NFC device to be applied in a battery-off mode (or low battery mode) that does not require writing to secure memory (e.g., the separate NV memory 322) as part of its operation. Embodiments of the present invention also prevent secure application operations that require secure memory writes in a battery-off or low battery mode.

NFC devices communicate using command-response pairs. The application may be selected implicitly or explicitly. In either case, the instruction to access the application includes an Application Identifier (AID). Thus, in one embodiment, an NFC device operating in a battery-off or low-battery mode that receives instructions for executing an application first determines (e.g., using controller 202) whether the application needs to have data written to it before determining whether the application should be enabled and/or executed.

In one embodiment, each NFC device includes a list of supported applications and optional related data elements (e.g., an AID table). The AID table may be stored, for example, in OTP memory, Electrically Erasable Programmable Read Only Memory (EEPROM), or flash memory of the NFC device. The list of AIDs in the AID table may be transmitted to the reader when the reader requests the list. The reader may then issue an instruction to execute an application corresponding to one of the transmitted AIDs.

For example, the list of applications may be stored in a directory file (such as "ef. dir"), such as the international standard ISO/IEC 7816-4 "identification card-integrated circuit card-part 4, published on 1, 15/2005: organization, security, and instruction for interaction (Identification cards-Part 4: Organization, security and command for exchange), which is hereby incorporated by reference in its entirety. The dir directory file includes a set of application identifiers and determines which instructions should be executed to select an application. However, it should be understood that embodiments of the present invention are applicable to any table that includes a list of applications and/or application identifiers.

In one embodiment, upon power-up of the host communication device, the communication device retrieves all secure elements (e.g., secure devices and/or secure memory) and updates the AID routing table with information regarding the write-only state of any particular application. In this embodiment, the write-only state (1) of the application is known by the host communication device; (2) available from a secure element of the storage application; (3) look up from a web-based look-up table for the application; or (4) unknown. If the write-only state of the application is unknown, the user may manually query to determine if the application is write-only.

Fig. 4A shows a table giving an exemplary AID table comprising an AID list 402 and (optionally) corresponding instructions 404 for performing AID 402. Fig. 4B shows a "battery off flag" column added to the table of fig. 4A. It should be understood that the AID and instructions shown in fig. 4A and 4B are exemplary and are used to illustrate embodiments of the present invention. According to an embodiment of the invention, if the NFC device is operating in battery-off mode, the NFC device checks the corresponding battery-off flag 406 against the AID 402 referenced in the instruction before executing the instruction 404. In one embodiment, the battery off flag 406 indicates that an application should be enabled during a battery off or low battery mode. In another embodiment, the battery off flag 406 indicates that an application should be disabled during a battery off or low battery mode.

In an embodiment of the present invention, the AID having the battery off flag set to "0" is not transmitted to the reader when the reader requests the available application list. Therefore, in this embodiment, when the NFC device operating in the tag operation mode operates in the battery-off mode, the reader cannot request execution of an application having a higher power requirement (for example, an application requiring writing of data). In another embodiment, the full list of AIDs is sent to the reader along with the respective battery off flag so that the reader knows that some applications based on the request are not executed. In another embodiment, the full list of AIDs is sent to the reader, but without attaching the battery off flag, and the NFC device operating in tag mode ignores the request to execute the application with the battery off flag set to "0".

For example, application 408 has a battery shutdown flag set to "1". In one embodiment, the flag indicates that the application 408 may be executing in a battery-off mode, for example, because the application 408 does not need to write to memory. On the other hand, the applications 409 and 410 have a battery off flag set to "0", which indicates that the application 410 cannot be executed in the battery off mode (e.g., because the application 410 needs to be written to memory during execution). Thus, in one embodiment, only AID 408 is sent to the reader requesting the list of available applications during the battery-off mode.

In an embodiment of the present invention, the battery shutdown flag 406 is a multi-bit power code 411, as shown in fig. 4C. For example, in embodiments of the present invention, the NFC device incorporates multiple power modes, and this power code 411 may be used to identify the minimum NFC device power code required to support an application. For example, in some embodiments, the NFC device may obtain sufficient power to execute some applications, but not enough power to execute other applications. In this case, the NFC device determines, before executing the application, whether the power code 411 indicates that the application requires more power than is currently available in the power mode of the NFC device.

In another implementation, the NFC device may allocate a portion of its OTP memory for applications that do not require a change in memory. In this case, the power required to be provided by battery operation may be lower. In this case, the power code 411 may indicate that the respective application is present in the OTP memory of the NFC device and requires a smaller amount of power.

In other embodiments of the present invention, the power code 411 is a binary code representing the least amount of power required by the application. In this case, the NFC device determines whether the amount of power currently available to execute the application meets or exceeds the power represented by the power code 411. It should be appreciated that in this embodiment, the "power" represented by the power code 411 may be any value (e.g., watts, volts, amps, joules, etc.) in any unit of measurement required by the application to perform.

It should also be understood that AID tables according to embodiments of the present invention may incorporate other features and/or columns. For example, other columns may be added to describe the location of the application (i.e., in which secure device and/or the address of the secure memory where the application is stored). In this example, this column may indicate that the secure device should be powered on to run the NFC device of the respective application.

Fig. 4C shows a table showing another example according to an embodiment of the present invention. Instead of using the battery off flag 406, the AID table of fig. 4C incorporates a power code 411. In this example, the NFC device has 4 power modes available (e.g., 00 indicating no power at all; 01 indicating there is sufficient power to run an application on its OTP memory; 10 indicating there is sufficient power to run an application on a separate NV memory; and 11 indicating there is sufficient power to run all applications).

When the NFC device receives a request for an available application, it checks to see in what power mode it is currently operating. For example, if the NFC device is operating in power mode 10, it only sends applications 409 and 410 to the reader. For example, the NFC device may determine the current power mode by checking the power level of the battery 316 of the host communication device 300, and checking the power generated by its own power harvesting module 210.

Since the application 409 is present on the NFC device itself (as shown in power mode 01), no other device needs to be powered on before the application 409 executes. The application 410 resides on a device "DEV 1". In one embodiment, the NFC device powers up the DEV1 after it sends the AID to the reader. In another embodiment, the NFC device waits for a request to execute the application 410 before powering on the DEV 1.

4. Method for providing NFC secure application support in battery off mode

A method of providing NFC secure application support in battery-off mode will now be described with reference to the flowchart of fig. 5. In step 502, a power mode of the NFC device (e.g., NFC device 200) is determined. For example, the NFC device may access a battery (e.g., battery 316) in the host communication device and/or a power harvesting module (e.g., power harvesting module 210) of the NFC device to determine how much power is available to the NFC device and what power mode of the available power corresponds.

In step 504, an application identifier request is received from a reader device. In step 506, the NFC device accesses the list of application identifiers. For example, in one embodiment, the list of application identifiers is an AID table (e.g., the AID table of fig. 4B and/or fig. 4C).

In step 508, a determination is made as to whether the NFC device has sufficient power to execute an application in this power mode. For example, the NFC device determines whether it is operating in a battery-off or low battery mode, or whether multiple power modes are supported, and whether the power currently available to it is sufficient to support the application.

In step 510, the NFC device transmits an application identifier if it determines that it has sufficient power to execute the application. In one embodiment, the NFC device sends a list of all applications it has sufficient power to execute. Further, in one embodiment, the NFC device provides power to a secure device storing the supported application prior to executing the application.

5. Conclusion

It is to be understood that the detailed description section and not the abstract section are intended to be used to interpret the claims. The abstract section may set forth one or more, but not all exemplary embodiments of the invention contemplated by the inventors, and thus, is not intended to limit the invention and the appended claims in any way.

The invention has been described above with the aid of functional blocks illustrating the implementation of specific functions and relationships thereof. Boundaries of these functional blocks have been arbitrarily defined herein for the convenience of the description. Alternate boundaries can be defined so long as the specified functions and relationships thereof are appropriately performed.

The foregoing description of the specific embodiments will so fully reveal the general nature of the invention that others can, by applying knowledge within the skill of the art, readily modify and/or adapt for various applications such specific embodiments, without undue experimentation, without departing from the general concept of the present invention. Therefore, such changes or modifications are intended to be within the meaning and range of equivalents of the disclosed embodiments, based on the teaching and guidance presented herein. It is to be understood that the phraseology or terminology herein is for the purpose of description and not of limitation, such that the terminology or phraseology of the present specification is to be interpreted by the skilled artisan in light of the teachings and guidance.

The above-described systems and methods may be implemented as a computer program executing on a machine, a computer program product, or a tangible and/or non-transitory computer-readable medium having stored instructions. For example, the functions described herein may be implemented by computer program instructions executed by a computer processor or any of the hardware devices listed above. The computer program instructions direct the processor to perform the signal processing functions described herein. The computer program instructions (e.g., software) may be stored in a tangible, non-transitory computer usable medium, a computer program medium, or any storage medium that is accessible by a computer or processor. Such media include memory devices such as RAM or ROM, or other types of computer storage media such as computer diskettes or CD-ROMs. Thus, any tangible, non-transitory computer storage medium having computer program code to direct a processor to perform the signal processing functions described herein is within the scope and spirit of the present invention.

While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example only, and not limitation. It will be apparent to persons skilled in the relevant art that various changes in form and detail can be made therein without departing from the spirit and scope of the invention. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents.

Claims (10)

1. An NFC device, comprising:

a power acquisition module;

a memory storing a list of application identifiers; and

a controller, wherein the controller is configured to:

receiving an application identifier request from a reader device,

the list of application identifiers is accessed and,

determining whether the amount of power available to the NFC device is sufficient to execute an application corresponding to the application identifier by accessing information in the list of application identifiers, and

transmitting the application identifier in response to a determination that the amount of power available to the NFC device is sufficient to execute the application.

2. The NFC device of claim 1, wherein the controller is further configured to determine whether a host communication device coupled to the NFC device has insufficient or no battery power to execute the application.

3. The NFC device of claim 1, wherein the list of application identifiers includes a field to indicate whether the application corresponding to the application identifier can be executed in a low power mode in which the NFC device does not have sufficient power to simultaneously execute a plurality of applications corresponding to the list of application identifiers.

4. The NFC device of claim 1, wherein the list of application identifiers corresponds to a plurality of applications, and wherein the controller device is further configured to:

determining which applications the NFC device has sufficient power to execute; and

transmitting a list of supported application identifiers corresponding to the application for which the NFC device has sufficient power to execute.

5. The NFC device of claim 1, further comprising a one-time programmable (OTP) memory, and wherein the controller is further configured to:

determining whether the application corresponding to the application identifier is stored on the OTP memory.

6. A communication device, comprising:

a battery; and

an NFC device, wherein the NFC device is configured to:

checking a power level of the battery to determine a power mode,

receiving an application identifier request from a reader device,

a list of application identifiers is accessed and,

determining whether the amount of power available in the power mode is sufficient to execute an application corresponding to the application identifier by accessing information in the list of application identifiers, and

transmitting the application identifier in response to a determination that the amount of power available in the power mode is sufficient to execute the application.

7. The communication device of claim 6, further comprising an electrically erasable programmable read-only memory (EEPROM) of a non-volatile (NV) flash memory, and wherein the NFC device is further configured to determine whether the application corresponding to the application identifier is stored on the EEPROM.

8. The communication device of claim 6, further comprising a security device storing the application corresponding to the application identifier.

9. The communication device of claim 6, wherein the communication device is configured to support a plurality of power modes, and wherein a power mode of the plurality of power modes indicates that the NFC device has sufficient power to execute an application stored in a one-time programmable (OTP) memory of the NFC device.

10. A method, comprising:

determining a power mode of the NFC device;

receiving an application identifier request from a reader device;

accessing a list of application identifiers;

determining, based on information in the list of application identifiers, whether an amount of power available in the power mode is sufficient to execute an application corresponding to the application identifier, and

transmitting the application identifier in response to a determination that the amount of power available in the power mode is sufficient to execute the application.