Circuit unit and NFC device for implementing near field communication

Abstract

The present application provides a circuit unit for implementing near-field communication and an NFC device. The solution includes an NFC antenna, an NFC chip, and an excitation circuit. The NFC antenna is connected to the NFC chip, which is in turn connected to the excitation circuit. The NFC chip is configured to obtain first energy when the NFC antenna senses a radio frequency field from a user terminal device and to provide a portion of the first energy to the excitation circuit. The excitation circuit is configured to use the energy obtained from the NFC chip to generate and emit an excitation signal, which is used to excite the user terminal device to communicate with the device containing the circuit unit.

Description

Technical Field

[0001] The present application relates to the technical field of near field communication, and in particular to a circuit unit for implementing near field communication and an NFC device. Background Art

[0002] Near Field Communication (NFC) technology, as a short-range wireless communication protocol, has been widely used in a variety of fields, including mobile payment, information exchange, smart home control, access control, identity authentication and identification, electronic ticketing, and anti-counterfeiting. Devices participating in NFC can include an NFC initiator and an NFC target. The NFC initiator (also known as the master) requires a power supply. The master uses the power supply's energy to generate an RF field and transmit data to the NFC target (also known as the slave) at a transmission rate of 106kbps, 212kbps, or 424kbps. The slave device does not generate an RF field and does not require a power supply. Instead, it converts the RF field generated by the master into electrical energy to power the slave's circuitry, receive data from the master, and transmit data back to the master at the same transmission rate using load modulation.

[0003] In practical applications, when using a mobile terminal device such as a smartphone as an NFC master, the NFC master incorporates numerous low-power designs, such as those for its own reader's transmit power, to control power consumption. This means that for the target device on the other end, only active power supply can achieve a good communication success rate with the mobile terminal, but this is costly and power-intensive. Using a low-cost passive solution often results in a very low communication success rate. This has hindered the widespread adoption of near-field communication using mobile terminals such as smartphones as NFC masters.

[0004] In view of this, there is a need to provide a near field communication solution with low power consumption and high success rate. Summary of the Invention

[0005] In view of this, embodiments of the present application provide a circuit unit for implementing near field communication and an NFC device, which are used to improve the success rate of near field communication under low power consumption conditions.

[0006] According to a first aspect of an embodiment of the present application, a circuit unit for implementing near-field communication is provided, including an NFC antenna, an NFC chip, and an excitation circuit, wherein the NFC antenna is connected to the NFC chip, and the NFC chip is connected to the excitation circuit, wherein the NFC chip is used to obtain first energy when the NFC antenna senses a radio frequency field of a user terminal device and provide part of the first energy to the excitation circuit; the excitation circuit is used to generate and emit an excitation signal using the energy obtained from the NFC chip, and the excitation signal is used to excite the user terminal device to communicate with the device including the circuit unit.

[0007] According to a second aspect of an embodiment of the present application, an NFC device is provided, including a circuit unit for implementing near-field communication, the circuit unit including an NFC antenna, an NFC chip, and an excitation circuit, the NFC antenna being connected to the NFC chip, and the NFC chip being connected to the excitation circuit, wherein the NFC chip is configured to obtain first energy when the NFC antenna senses a radio frequency field of a user terminal device, and to provide part of the first energy to the excitation circuit; the excitation circuit is configured to generate and emit an excitation signal using the energy obtained from the NFC chip, wherein the excitation signal is configured to excite the user terminal device to communicate with a device including the circuit unit.

[0008] One embodiment of the present specification can achieve at least the following beneficial effects: by setting up an excitation circuit and using the NFC chip to obtain energy and provide it to the excitation circuit when the NFC antenna senses the radio frequency field of the user terminal device, so that the excitation circuit transmits an excitation signal for stimulating the user terminal device to switch to the standard card inspection mode and then perform near-field communication, thereby improving the success rate of near-field communication in a low-power manner. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In order to more clearly illustrate the embodiments of this specification or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in this application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0010] Figure 1 A schematic diagram of an application scenario of a circuit unit for implementing near field communication provided in an embodiment of this specification;

[0011] Figure 2 A schematic diagram of a circuit unit for implementing near field communication provided in an embodiment of this specification;

[0012] Figure 3 A detailed schematic diagram of a circuit unit for implementing near field communication provided in an embodiment of this specification;

[0013] Figure 4 A schematic diagram of another circuit unit for implementing near field communication provided in an embodiment of this specification;

[0014] Figure 5 A schematic diagram of another circuit unit for implementing near field communication provided in an embodiment of this specification;

[0015] Figure 6 A schematic diagram of another circuit unit for implementing near field communication provided in an embodiment of this specification;

[0016] Figure 7 A schematic diagram of a scenario in which a circuit unit for implementing near field communication performs near field communication with a user terminal device operating in active mode in an actual application scenario provided in an embodiment of this specification;

[0017] Figure 8 A schematic diagram of the structure of a metal sheet for an NFC antenna provided in an embodiment of this specification;

[0018] Figure 9 A schematic structural diagram of another metal sheet for an NFC antenna provided in an embodiment of this specification;

[0019] Figure 10 A schematic diagram of an NFC antenna including a metal sheet and a metal coil provided in an embodiment of this specification;

[0020] Figure 11 A schematic diagram of another NFC antenna including a metal sheet and a metal coil provided in an embodiment of this specification. DETAILED DESCRIPTION

[0021] The following description sets forth many specific details to facilitate a thorough understanding of the present application. However, the present application can be implemented in many other ways than those described herein, and those skilled in the art can make similar generalizations without violating the scope of the present application. Therefore, the present application is not limited to the specific implementations disclosed below.

[0022] The terms used in one or more embodiments of the present application are for the purpose of describing specific embodiments only and are not intended to limit one or more embodiments of the present application. The singular forms "a", "the" and "the" used in one or more embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used in one or more embodiments of the present application refers to and includes any or all possible combinations of one or more associated listed items.

[0023] It should be understood that although the terms first, second, etc. may be used to describe various information in one or more embodiments of the present application, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from each other. For example, without departing from the scope of one or more embodiments of the present application, the first may also be referred to as the second, and similarly, the second may also be referred to as the first. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0024] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with the relevant laws, regulations and standards of the relevant regions, and provide corresponding operation entrances for users to choose to authorize or refuse.

[0025] First, the terms involved in one or more embodiments of the present application are explained.

[0026] NFC: Near Field Communication, is a short-range, high-frequency radio communication technology.

[0027] NFC active mode: also known as reader mode. In active mode, an NFC device acts as a reader, emitting a radio frequency field to identify and read / write information from passive NFC devices. An NFC device in active mode is called an active NFC device or an NFC master device.

[0028] NFC passive mode: also known as card emulation mode. In passive mode, an NFC device simulates a card, passively responding to the radio frequency field emitted by other devices and allowing information to be read and written. An NFC device in passive mode is also called a passive NFC device or an NFC slave device.

[0029] LPCD mode: also known as Low Power Card Detection (LPCD) mode or Low Power Card Search mode, where LPCD stands for Low Power Card Detection. LPCD is a technology used in NFC to efficiently detect nearby contactless smart cards or tags. It primarily reduces the power consumption of an NFC reader while waiting for a smart card or tag to approach. An NFC reader in LPCD mode periodically transmits low-power pulses. When the NFC reader detects a change in the signal amplitude at the antenna that exceeds a preset threshold, it determines that an NFC device is in proximity and initiates further interaction. Specifically, when a card enters the RF field, the signal's amplitude and phase change. LPCD mode utilizes a software-based card detection mechanism, using an LPCD algorithm to detect these changes. By analyzing the in-phase (I) and quadrature (Q) components of the received signal, it determines the presence of a card, triggering further NFC communication. LPCD mode is particularly important in portable devices such as mobile phones, primarily due to its low power consumption. Mobile phones typically require long periods of standby time, and frequent activation of the NFC function can significantly drain the battery. LPCD mode allows the phone to continuously detect NFC signals in the background while maintaining low energy consumption. Once a card is detected, the phone can quickly switch from a low-power state to a full-featured state to perform NFC transactions or exchange data.

[0030] Standard card detection mode: also known as normal card detection mode or normal card search mode. To improve the speed and success rate of NFC communication, the NFC reader is typically in full functionality during NFC communication, i.e., standard card detection mode. In actual applications, an NFC reader (for example, a mobile terminal device such as a mobile phone) emits a 13.56MHz sine wave in both LPCD mode and standard card detection mode. The difference lies in the different transmission timing and amplitude of the sine wave in LPCD mode and standard card detection mode. For example, in LPCD mode, the pulse width is typically in the microsecond range, while in standard card detection mode, the pulse width is typically in the tens of milliseconds.

[0031] NFC tag: The full name is Near Field Communication tag. It is a small device based on near-field communication technology that can realize data exchange between devices at close range. NFC tags usually include a microchip and an antenna. The chip stores information (for example, ID, URL, etc.), while the antenna is responsible for receiving and sending data. NFC tags are passive devices that can operate without an external power source. In actual application, when an NFC reader (such as an NFC-enabled smart mobile device) approaches an NFC tag, the magnetic field generated by the NFC reader will be sensed by the tag's antenna, thereby generating enough power to activate the chip inside the tag, enabling the tag to send the information stored on it.

[0032] NFC technology has been widely used in many fields such as mobile payment, information exchange, smart home control, access control, identity authentication and recognition, electronic ticketing, anti-counterfeiting, etc. For example, in the field of mobile payment, payment methods based on NFC technology are currently booming both abroad and domestically.

[0033] In mobile payment scenarios, the current mainstream NFC-based payment method uses the cash register (payment end) as a card reader operating in active mode, enabling payment by reading information passively simulated on the mobile device (payment end). However, the electronic wallets used by consumers are all provided by the mobile device manufacturer. To use the NFC payment function of their mobile device, users need to open a variety of wallets according to the device manufacturer's requirements, which is not only difficult to manage but also poses information security risks. Moreover, not all mobile device models currently support passive card emulation functions such as financial payment. Therefore, the widespread adoption and application of NFC payment methods using mobile devices operating in passive mode is limited. Therefore, it is necessary to enable mobile devices to operate in active mode.

[0034] However, the NFC payment method in which mobile devices work in active mode also has some problems in practice. Specifically, mobile devices are usually battery-powered and are very sensitive to power consumption. In order to control power consumption, they usually make many low-power designs for the transmission power of their own card readers, such as setting the LPCD mode. For example, when the mobile phone is off, the card reading function is usually turned off, and most mobile phones will automatically enter the LPCD mode after a period of time after the screen is turned on. When a mobile device in LPCD mode is close to the NFC target device at the other end, it can be switched to the standard card detection mode. In actual application, when the mobile device senses that the intensity change of the radio frequency signal it transmits when being sensed by the NFC target device at the other end is greater than or equal to the preset threshold, the mobile device will be awakened from the LPCD mode and enter the standard card detection mode. However, in LPCD mode, the signal strength emitted by the mobile device is weak, and the amplitude of the emitted RF signal is lower than that in the standard card detection mode. Therefore, the influence of the NFC target device on the other end on the signal will also be reduced accordingly, making it impossible for the mobile device to determine whether there is an NFC target device nearby by the changing amplitude of the signal, which in turn causes the mobile device to be unable to obtain correct judgment results and unable to switch to the standard card detection mode, thereby significantly reducing the success rate of the mobile device sensing the NFC target device, thereby affecting the success rate of near-field communication and the user experience.

[0035] For example, using a smartphone as the primary NFC device for near-field communication with a cash register can only achieve a good communication success rate if the other end uses an active device to interact with the phone. However, active cash register devices not only consume high power but also have complex and expensive designs, resulting in high offline deployment costs, making them unsuitable for widespread adoption. Low-cost, passive payment solutions often have very low communication success rates (for example, current passive payment solutions have a success rate of less than 70%, and even less than 50% for some mobile devices). This low success rate also hinders the promotion of this payment model.

[0036] In view of this, in the embodiments of this specification, a passive, low-power near-field communication solution for an NFC slave device is provided. By providing an excitation circuit, a portion of the energy obtained by the NFC chip when the NFC antenna senses the radio frequency field of the user terminal device is provided to the excitation circuit. The excitation circuit then emits an excitation signal to stimulate the user terminal device to communicate with the NFC slave device. This improves the success rate of near-field communication with low power consumption and low cost, thereby promoting the production and promotion of convenient NFC payment products that serve as NFC slave devices.

[0037] Figure 1 A schematic diagram of an application scenario of a circuit unit for implementing near field communication provided in an embodiment of this specification.

[0038] like Figure 1 As shown, when a mobile terminal device 100 with NFC functionality is close to an NFC tag 201 or a payment terminal device 202 with NFC functionality, near-field communication can occur between the mobile terminal device 100 and the NFC tag 201 or the payment terminal device 202. As a result, the mobile terminal device 100 can obtain information provided by the NFC tag 201 or the payment terminal device 202. During this process, the mobile terminal device 100 operates in active mode, and the NFC tag 201 or the payment terminal device 202 operates in passive mode.

[0039] although Figure 1 The NFC host device that initiates NFC communication is shown to be a mobile terminal device 100 of the smartphone type. However, when the solution of this specification is actually applied, the NFC host device may also include but is not limited to smart wearable devices such as smart watches and smart glasses. Figure 1 The NFC slave device is shown as an NFC tag 201 or a payment terminal device 202, but when the solution of this specification is actually applied, the NFC slave device may also include but is not limited to an electronic door lock, a payment code card, an entry / exit gate, etc.

[0040] In actual applications, an NFC master device, such as mobile terminal device 100, can emit a radio frequency field. An NFC slave device, such as NFC tag 201 or payment terminal device 202, can respond to the near-field communication signal emitted by the NFC master device and send business information to the mobile terminal device 100. The business information can vary depending on the application scenario. For example, in a payment scenario, business information may include payment order information; in a food ordering scenario, business information may include a uniform resource locator for opening the food ordering page; and in the context of product traceability, business information may include product description information.

[0041] The circuit unit for implementing near field communication provided by the solution of the embodiment of this specification can be installed in Figure 1 The NFC device provided by the embodiment of the present specification can be used as an NFC tag 201 or a payment terminal 202. Figure 1 As shown, an NFC tag 201 or a payment terminal device 202 is used.

[0042] In the solution provided in the embodiments of the specification, in the circuit unit for realizing near-field communication, the NFC chip's own ability to recover the energy of the radio frequency field of the approaching user terminal device is utilized, and the recovered energy is provided to the excitation module, which excites the user terminal device through the excitation module, so that the user terminal device can sense the presence of the NFC slave device (the NFC slave device includes the circuit unit provided in the embodiments of this specification), and then conduct normal near-field communication with the NFC slave device.

[0043] In one or more embodiments of the present specification, a circuit unit for implementing near field communication is provided.

[0044] Figure 2 FIG2 shows a schematic diagram of a circuit unit 300 for implementing near field communication provided in an embodiment of this specification.

[0045] like Figure 2 As shown in , specifically, a circuit unit 300 for implementing near field communication may include an NFC antenna 301, an NFC chip 302 and an excitation circuit 303, wherein the NFC chip 302 may be connected to the NFC antenna 301, and the NFC chip 302 may be connected to the excitation circuit 303.

[0046] The NFC chip 302 and the NFC antenna 301 connected thereto may be capable of signal transmission and reception, as well as signal modulation and demodulation. Specifically, the NFC chip 302 and the NFC antenna 301 connected thereto may operate in passive mode and communicate directly with a user terminal device (e.g., a smartphone) operating in active mode.

[0047] The communication carrier frequency of NFC (Near Field Communication) technology is 13.56 MHz. This frequency is standardized globally, ensuring interoperability between NFC devices from different manufacturers. The 13.56 MHz frequency was chosen to ensure efficient and secure data exchange over short distances (typically a few centimeters to approximately 20 centimeters). The radio frequency field with a communication carrier frequency of 13.56 MHz has the ability to provide energy. The radio frequency field emitted by an NFC master device operating in active mode can typically provide energy to an NFC slave device. An NFC slave device operating in passive mode can directly operate and communicate with the NFC master device using energy provided by the NFC master device. In the embodiments of this specification, the NFC chip 302 and the NFC antenna 301 connected thereto can be commercially available chips, such as the NXP NTAG5LINK chip, the Fudan Micro FM11NT082C chip, and related chips from manufacturers such as ST, but are not limited to these examples.

[0048] In the embodiments of this specification, considering that the user terminal device may be in LPCD mode and it is difficult to communicate successfully and difficult to be awakened, in order to improve the success rate of communication, the energy recovered by the NFC chip 302 working in passive mode can be provided to the excitation circuit 303, and the excitation circuit 303 emits an active radio frequency field to excite the user terminal device, so that the user terminal device switches to the standard card inspection mode and performs near-field communication data interaction, thereby improving the success rate of near-field communication.

[0049] like Figure 2 As shown, an excitation circuit 303 is provided in the circuit unit 300 for implementing near-field communication. Specifically, the NFC chip 302 can be electrically connected to the excitation circuit 303. As a result, the NFC chip 302 can provide a portion of the energy recovered by the NFC antenna 301 based on the proximity of the radio frequency field to the excitation circuit 303, thereby enabling the excitation circuit 303 to operate. In actual applications, the NFC chip 302 can output the recovered energy to the excitation circuit 303 through, for example, the VOUT pin.

[0050] Furthermore, the NFC chip 302 can be configured to obtain first energy when the NFC antenna 301 senses the radio frequency field of the user terminal device, and provide part of the first energy to the excitation circuit 303. The excitation circuit 303 can be configured to generate and emit an excitation signal using the energy obtained from the NFC chip 302, wherein the excitation signal is used to excite the user terminal device to communicate with the device including the circuit unit 300.

[0051] Furthermore, in the circuit unit 300 , the NFC antenna 301 may be connected to the excitation circuit 303 ; and the excitation circuit 303 may be configured to radiate the excitation signal to the user terminal device via the NFC antenna.

[0052] In one or more embodiments of this specification, the NFC chip 302 can be communicatively connected to the excitation circuit 303. Specifically, the NFC chip 302 can sense the field strength state of the user terminal device through the NFC antenna 301 and output a related signal (e.g., an interrupt signal) to the excitation circuit 303.

[0053] More specifically, the NFC chip 302 can also be used to send an interrupt signal to the excitation circuit 303 when the NFC antenna 301 senses that the radio frequency field of the user terminal device is approaching; accordingly, the excitation circuit 303 can be specifically used to generate and send an excitation signal based on the signal characteristics of the interrupt signal when it is determined that the user terminal device is in a low-power card detection mode; the excitation signal is used to switch the user terminal device in the low-power card detection mode to the standard card detection mode.

[0054] Figure 3 FIG2 shows a detailed schematic diagram of a circuit unit 300 for implementing near field communication provided in an embodiment of this specification.

[0055] like Figure 3 As shown in the figure, a circuit unit 300 for implementing near field communication may include an NFC antenna 301, an NFC chip 302, and an excitation circuit 303. Furthermore, the excitation circuit 303 may include a controller 3031 and a signal generator 3032. When the controller 3031 detects a related interrupt signal and controls the signal generator 3032 to start field radiation excitation through a hardware enable signal when necessary, the user terminal device at the other end is awakened.

[0056] Optionally, the controller 3031 may control the signal generator 3032 to start field radiation excitation when it is determined based on the interrupt signal that the user terminal device at the other end is in the LPCD state.

[0057] Specifically, the controller 3031 can be configured to use the energy obtained from the NFC chip 302 to determine whether the user terminal device is in the low-power card detection mode based on the signal characteristics of the interrupt signal; and if the user terminal device is in the low-power card detection mode, send a hardware enable signal to the signal generator 3032. Accordingly, the signal generator 3032 can be configured to use the energy obtained from the NFC chip 302 to generate and send the excitation signal in response to the hardware enable signal.

[0058] In actual application, the NFC chip 302 can be electrically connected to the excitation circuit 303 to provide energy to the excitation circuit 303. Specifically, the NFC chip 302 can be electrically connected to the controller 3031 and the signal generator 3032 to provide energy to the controller 3031 and the signal generator 3032 respectively.

[0059] The NFC chip 302 can be in communication with the excitation circuit 303 to output an interrupt signal to the excitation circuit 303. Specifically, the NFC chip 302 can be in communication with the controller 3031 and output an interrupt signal to the controller 3031. Furthermore, the controller 3031 can execute a preset judgment process and, if it determines that an excitation signal needs to be transmitted, output a hardware enable signal to the signal generator 3032 to enable the signal generator 3032 to transmit the excitation signal.

[0060] In actual application, the NFC chip 302 can communicate with the controller 3031 through a communication interface such as I2C or SPI. In specific implementation, a software program can be injected into the NFC chip 302 so that when the NFC chip 302 obtains a signal of an approaching radio frequency field based on the induction of the NFC antenna 301, it outputs an interrupt signal to the controller 3031, so that the controller 3031 can understand the characteristics of the radio frequency field.

[0061] Taking the Fudan Micro FM11NT082C chip as an example, when the NFC chip 302 detects a change in field strength, it can output a high-level interrupt to the controller 3031 through the Interrupt Request (IRQ) pin to establish communication between the NFC chip 302 and the controller 3031.

[0062] Specifically, the characteristics of the field strength signal of the radio frequency field emitted by the user terminal device may be carried in the interruption signal.

[0063] In actual applications, the signal characteristics of the interrupt signal may include at least one of a pulse width, a time period, or a pulse amplitude, but are not limited thereto. In actual applications, determining whether the user terminal device is in the low-power card detection mode may specifically include: determining whether the user terminal device is in the low-power card detection mode based on at least one of a pulse width, a time period, or a pulse amplitude of the interrupt signal.

[0064] Specifically, the signal characteristics of the terminal request information sent by the NFC chip 302 can be used to reflect the characteristics of the radio frequency field of the user terminal device. When the user terminal device is in different card detection states, the characteristics of the transmitted radio frequency field are different. As a result, the characteristics of the interrupt signal generated by the NFC chip and sent to the controller 3031 are different.

[0065] For example, compared to the standard card detection mode, when the user terminal device is in LPCD mode, the pulse width of the transmitted RF field signal is shorter, and accordingly, the pulse width of the interrupt signal is shorter. For another example, compared to the standard card detection mode, when the user terminal device is in LPCD mode, the time period of the transmitted RF field signal is longer, and accordingly, the time period of the interrupt signal is longer. For another example, compared to the standard card detection mode, when the user terminal device is in LPCD mode, the pulse amplitude of the transmitted RF field signal is weaker, and accordingly, the pulse amplitude of the interrupt signal is weaker.

[0066] Furthermore, in order to save energy, the controller 3031 may control the signal generator 3032 to start the field radiation excitation when it is determined that the information in the NFC chip 302 has not been read.

[0067] In actual use, if the NFC chip successfully communicates with a user terminal device and the information in NFC chip 302 is read by the user terminal device, the NFC chip will output corresponding flag information according to the NFC chip's programming. In actual use, when controller 3031 receives an interrupt signal, it can read the flag information from the NFC chip via a communication interface (e.g., I2C, SPI, etc.) and determine whether communication was successful based on the flag information.

[0068] Specifically, the controller 3031 may also be configured to utilize energy obtained from the NFC chip 302 and, based on flag information obtained from the NFC chip 302, determine whether communication between the user terminal device and the NFC chip 302 is successful; and, if the user terminal device is in the low-power card detection mode and communication between the user terminal device and the NFC chip 302 is unsuccessful, send a hardware enable signal to the signal generator 3032. Accordingly, the signal generator 3032 may utilize energy obtained from the NFC chip 302 to generate and send the excitation signal in response to the hardware enable signal.

[0069] That is, the excitation circuit 303 can be specifically used to generate and send an excitation signal when it is determined based on the signal characteristics of the interrupt signal that the user terminal device is in a low-power card detection mode and the NFC chip fails to communicate successfully with the user terminal device.

[0070] In one or more embodiments of this specification, in order to further improve the efficiency of recovering energy of the radio frequency field provided by the NFC master device operating in the active mode, an energy recovery circuit may be further provided.

[0071] Figure 4 FIG2 shows a schematic diagram of another circuit unit 310 for implementing near field communication provided in an embodiment of this specification.

[0072] like Figure 4 As shown in , a circuit unit 310 for implementing near-field communication may include an NFC antenna 301, an NFC chip 302, and an excitation circuit 303. Furthermore, the circuit unit 310 may further include a sorting circuit 304, which may be connected to the NFC antenna 301 and the excitation circuit 303. Specifically, the sorting circuit 304 may be configured to obtain second energy when the NFC antenna 301 senses a radio frequency field of a user terminal device, and to provide at least a portion of the second energy to the excitation circuit 303.

[0073] Specifically, the 13.56 MHz sine wave sensed by the NFC antenna can be output to the subsequent excitation circuit 303 through the conditioning circuit 304. The conditioning circuit 304 can be electrically connected to the excitation circuit 303, and more specifically, can be electrically connected to the controller 3031 and the signal generator 3032 to provide energy to the controller 3031 and the signal generator 3032.

[0074] In one or more embodiments of this specification, considering that the field period of the LPCD is particularly short, an additional energy supply module may be optionally provided to supplement the power supply to the excitation circuit 303 during special periods to ensure the completion of a communication cycle.

[0075] Figure 5 FIG2 shows a schematic diagram of another circuit unit 320 for implementing near field communication provided by an embodiment of this specification.

[0076] like Figure 5 As shown in the figure, a circuit unit 320 for realizing near field communication may include an NFC antenna 301, an NFC chip 302, an excitation circuit 303 and a sorting circuit 304, and further, the circuit unit 320 may also include an energy supply module 305, and the energy supply module 305 is connected to the excitation circuit 303 for providing a third energy to the excitation circuit 303.

[0077] Optionally, the energy supply module 305 can be configured as a rechargeable module. In this case, the energy recovered by the NFC chip 302 and the conditioning circuit 304 can be supplied to the rechargeable energy supply module 305 and then, when needed, to the excitation circuit 303, thereby improving energy utilization efficiency. Furthermore, the rechargeable energy supply module 305 can have an external charging port to obtain additional energy.

[0078] In actual application, the energy supply module 305 can be specifically configured as a button battery, a lithium battery, etc.

[0079] It should be noted that the solution of providing an energy supply module 305 for providing additional energy to the excitation circuit 303 in the embodiment of this specification is different from the solution of the active NFC chip in the related art. In the active NFC chip in the related art, a power supply is usually provided for directly powering the NFC chip, rather than further providing a supplementary power supply for powering the excitation circuit 303 on the basis of providing the excitation circuit 303. Moreover, in the embodiment of this specification, the energy supply module 305 plays the role of a supplementary power supply and is used as a fallback solution. In other words, even if the energy supply module 305 is not used, the excitation circuit 303 can still be driven by recycling the energy sensed by the NFC antenna, thereby waking up the opposite device and improving the success rate of near-field communication.

[0080] In one or more embodiments of this specification, another antenna may be provided to radiate the excitation signal generated by the excitation circuit 303 .

[0081] Figure 6FIG2 shows a schematic diagram of another circuit unit 330 for implementing near field communication provided in an embodiment of this specification.

[0082] like Figure 6 As shown in the figure, a circuit unit 330 for implementing near field communication may include an NFC antenna 301, an NFC chip 302 and an excitation circuit 303, and further, the circuit unit 330 may also include a second NFC antenna 306, which is connected to the excitation circuit 303; the excitation circuit 303 is used to radiate the excitation signal to the user terminal device through the second NFC antenna 306.

[0083] Different from Figure 2 In the embodiment shown, Figure 6 In the illustrated embodiment, the excitation signal can be radiated by a separate NFC antenna. By providing a second NFC antenna 306 to radiate the excitation signal, on the one hand, a complex time-division multiplexing design is not required, resulting in a simpler design and higher signal transmission efficiency. On the other hand, since a separate antenna is provided, the shape and position of the second NFC antenna can be more flexibly configured compared to reusing the original antenna, thereby greatly improving the radiation intensity of the excitation signal and better inductively coupling with the user terminal device at the other end, further increasing the probability of waking the user terminal device from LPCD mode, thereby improving the success rate of near-field communication.

[0084] like Figure 6 As shown in Figure 2 Based on the embodiment shown, the present invention is optimized to replace the NFC antenna 301 with the second NFC antenna 306. Alternatively, the NFC antenna 301 and the second NFC antenna 306 can jointly transmit the excitation signal, thereby further improving signal transmission efficiency, increasing the probability of waking the user terminal device from LPCD mode, and thus improving the success rate of near-field communication.

[0085] Compared with the above-mentioned embodiment Figure 2 Modifications to the embodiment shown can similarly be made to the embodiment shown. Figure 4 and Figure 5 Similar modifications are made to the embodiment shown in FIG.

[0086] Specifically, for Figure 4 The circuit unit 310 shown can be improved to further include a second NFC antenna 306 , so that the excitation signal can be transmitted through the second NFC antenna 306 , or the excitation signal can be transmitted through both the NFC antenna 301 and the second NFC antenna 306 .

[0087] Similarly, for Figure 5 The circuit unit 320 shown can be improved to further include a second NFC antenna 306 , so that the excitation signal can be transmitted through the second NFC antenna 306 , or the excitation signal can be transmitted through both the NFC antenna 301 and the second NFC antenna 306 .

[0088] According to the above description, the embodiment of this specification provides a schematic diagram of a scenario in which a circuit unit for implementing near field communication performs near field communication with a user terminal device operating in active mode in an actual application scenario, such as Figure 7 shown.

[0089] like Figure 7 As shown in FIG, the circuit unit may include an NFC antenna 301, an NFC chip 302, and an excitation circuit 303. The excitation circuit 303 may specifically include a controller 3031 and a signal generator 3032. When a user terminal device operating in active mode approaches the NFC antenna 301, the NFC antenna 301 senses the proximity of the radio frequency field. The NFC chip 302 connected to the NFC antenna 301 can, on the one hand, output a portion of the energy recovered from the NFC antenna 301 to the excitation circuit 303. On the other hand, it can generate an interrupt signal based on changes in the field signal sensed by the NFC antenna 301 and send it to the excitation circuit 303. When the excitation circuit 303 determines that a preset condition is met based on the interrupt signal, it will emit an excitation signal and radiate it through the NFC antenna 301 to wake the user terminal device from LPCD mode. Specifically, the excitation signal can be radiated by the NFC antenna 301, or by a second NFC antenna 306 provided separately.

[0090] Optionally, to improve the energy recovery rate of the radio frequency field emitted by the user terminal device operating in active mode, a conditioning circuit 304 connected between the NFC antenna 301 and the excitation circuit 303 may be provided. The conditioning circuit 304 is configured to collect the energy of the radio frequency field when the NFC antenna 301 senses the radio frequency field and output it to the excitation circuit 303.

[0091] In practical applications, using both the NFC chip 302 and the conditioning circuit 304 for energy recovery can significantly improve the energy recovery rate. For example, during a single RF field approach, approximately 30mW to 50mW (1.8V, 16mA to 28mA) of energy can be recovered and supplied to the subsequent excitation circuit 303.

[0092] Furthermore, the controller 3031 may include a low-power microcontroller unit (MCU). Typically, a low-power MCU has a sleep power consumption of uA and an operating capacity of tens of uA at 1MHz (such as the National N32L40 series and ST's related MCUs). Typically, a low-power MCU operates at around 40MHz and can control the operating current to around 3.6mW-7.2mW (1.8V, 2-4mA).

[0093] In actual application, when the NFC chip 302 cannot directly wake up the peer device through the passive load change of the NFC antenna 301, resulting in communication obstruction, the energy recovered by the above-mentioned NFC chip 302 and the sorting circuit 304 can be used to supply the low-power MCU with energy. Specifically, when a field signal approaches the NFC antenna 301, the NFC chip 302 and the sorting circuit 310 can start to recover energy to supply the low-power MCU with energy, so that it works in a low-power state. Afterwards, when the NFC chip 302 detects the field and sends an interrupt signal, it will wake up the low-power MCU from the low-power state. The low-power MCU can further judge the working state of the peer device based on the pulse width, time period, pulse amplitude and other comprehensive information of the interrupt signal. If it is determined that the peer device is in the LPCD state, the low-power MCU can control the signal transmitter to transmit a 13.56M active field to wake up the peer device and then complete the next step of communication, thereby improving the communication success rate.

[0094] Furthermore, the signal generator 3032 may include an active crystal or RC oscillator circuit, mainly used to generate a signal field of approximately 12 to 14 MHz, with a power consumption of approximately 3.6 mW to 5.4 mW (1.8 V, 2 to 3 mA). Specifically, under the control of the controller 3031, the signal generator 3032 can generate a signal field that can be transmitted to the antenna through the link and radiated outward. Optionally, it can be transmitted to the NFC antenna 301 for outward radiation (NFC antenna 301 is time-division multiplexed), such as Figures 2 to 5 Alternatively, it can be conducted to the second NFC antenna 306 to radiate outwards, as shown in Figure 6 As shown in .

[0095] In one or more embodiments of this specification, the frequency of the active field radiated outward based on the excitation signal provided by signal generator 3032 can be tuned to coincide with the frequency of the radio frequency field of the user terminal device, that is, to achieve multiple resonance points. Specifically, it can be set to 12-14 MHz. More specifically, it can be set to approximately 13.56 MHz.

[0096] In one or more embodiments of this specification, the NFC antenna 301 in the circuit unit (including the circuit unit 300 , 310 , 320 , or 330 ) may be further optimized.

[0097] Figure 8 A schematic structural diagram of a metal sheet for an NFC antenna provided in an embodiment of this specification is shown.

[0098] In a circuit unit for implementing near field communication, the NFC antenna 301 may include: Figure 8 The metal sheet 401 shown in FIG. The metal sheet 401 can be bent in the plane where the metal sheet 401 is located, so that both ends of the metal sheet 401 along the length direction are close to each other and form a gap space.

[0099] Figure 9 A schematic structural diagram of another metal sheet for an NFC antenna provided in an embodiment of this specification is shown.

[0100] In a circuit unit for implementing near field communication, the NFC antenna 301 may include: Figure 9 The metal sheet 402 shown in FIG. Figure 8 Similarly, the metal sheet 402 may be bent within the plane where the metal sheet 402 is located, so that two ends of the metal sheet 402 along the length direction are close to each other and form a gap space.

[0101] Specifically, in Figure 8 and Figure 9 The metal sheet shown can be different from the conventional metal wire coil structure used for NFC antenna 301. Instead, a metal sheet bent into a ring in a plane is used. In actual applications, the middle area enclosed by metal sheet 401 or 402 can be used to place NFC chip 302. The relative position of NFC chip 302 and metal sheet 401 or 402 is not limited to this.

[0102] It is understandable that Figure 8 and Figure 9 These are just two specific examples of metal sheets. In actual applications, the shape of the metal sheet is not limited to being circular or rectangular, but can also be polygonal or irregular. The curvature of the metal sheet can be set according to actual needs. For example, it can be adaptively adjusted to the spatial location where the NFC chip is installed.

[0103] Furthermore, the metal sheet may be made of a conventional metal used for communication antennas, for example, copper.

[0104] Alternatively, in actual applications, a metal sheet can be used instead of a metal coil as an NFC antenna. Specifically, both ends of the metal sheet along the length direction can serve as feeding points for the NFC antenna 301. In actual applications, the NFC antenna 301 can be connected to the NFC chip 302 through the feeding points.

[0105] Optionally, in practical applications, a metal sheet and a metal coil may be used in combination in the NFC antenna 301. Specifically, the metal coil may include a feeding point connected to the NFC chip 302, and the metal sheet may not include a feeding point.

[0106] Unlike traditional linear metal coils, in the embodiments of this specification, the NFC antenna can be configured as a sheet-shaped metal ring with a large area within the plane of the antenna body. This can increase the antenna's equivalent inductance, for example, to 500nH to 2uH. With this inductance, when matched with a capacitor to form a resonant circuit with a resonance point around 13.56MHz, it can achieve high radiated energy and can find a suitable matching capacitor.

[0107] This improves the ability to wake up a user terminal device from an LPCD state by influencing the inductive load of the other user terminal device. It also improves the efficiency of energy recovery. Furthermore, it increases the intensity and efficiency of the excitation signal radiated by the NFC antenna 301. Overall, this improves the success rate of near-field communication between the NFC slave device and the user terminal device.

[0108] Figure 10 A schematic diagram of an NFC antenna including a metal sheet and a metal coil provided in an embodiment of this specification.

[0109] Specifically, in a circuit unit for implementing near field communication, the NFC antenna 301 includes a metal sheet (for example, Figure 8 The metal sheet 401 shown or Figure 9 On the basis of the metal sheet 402 shown in FIG. 4 , the NFC antenna 301 may further include a metal coil. The metal coil may be located in the same plane as the metal sheet, and the metal coil may be located in an area surrounded by the bent metal sheet.

[0110] like Figure 10 As shown in , the metal coil 501 can be located in the area surrounded by the bent metal sheet 401. In actual application, the NFC chip 302 can be further placed in the area surrounded by the metal coil 501.

[0111] Figure 11 A schematic diagram of another NFC antenna including a metal sheet and a metal coil provided in an embodiment of this specification.

[0112] Specifically, in a circuit unit for implementing near field communication, the NFC antenna 301 includes a metal sheet (for example, Figure 8The metal sheet 401 shown or Figure 9 In the case of the metal sheet 402 shown in FIG. 4 , the NFC antenna 301 may further include a metal coil, which may be arranged to overlap with the metal sheet; the metal sheet may be closer to the scanned side of the device including the circuit unit than the metal coil.

[0113] like Figure 11 As shown in , the metal sheet 401 can be arranged closer to the scanned side of the device including the circuit unit than the metal coil 501.

[0114] In actual application, by looping or overlapping the metal sheet and the metal coil in the NFC antenna module, the annular metal sheet can act as an amplifier, thereby improving the signal transmission efficiency and strength, thereby improving the success rate of waking up the user terminal device from the LPCD mode, and thus improving the success rate of near-field communication.

[0115] In addition, in the embodiments of this specification, in order to enable the NFC antenna to better couple with the antenna of the user terminal device at the other end, a matching circuit can be set (for example, by connecting a certain capacitance in parallel) to tune the NFC antenna to a transmission frequency band of 13.56 MHz (12-14 MHz), thereby achieving better coupling with the antenna of the user terminal device at the other end and enhancing energy conversion efficiency.

[0116] In one or more embodiments of this specification, similar to the NFC antenna 301 , when the second NFC antenna 306 is used in the circuit module, the second NFC antenna 306 may also be made of a metal sheet.

[0117] Specifically, in a circuit unit for implementing near field communication, the second NFC antenna 306 included therein may include a metal sheet, and the metal sheet is bent in the plane where the metal sheet is located so that the two ends of the metal sheet along the length direction are close to each other and form a gap space. For example, the metal sheet may be as follows Figure 8 The metal sheet 401 shown or Figure 9 The shape of the metal sheet 402 is not limited to this.

[0118] Alternatively, in actual applications, a metal sheet can be used instead of a metal coil as the NFC antenna. Specifically, both ends of the metal sheet along the length direction can serve as feeding points for the second NFC antenna 306. In actual applications, the second NFC antenna 306 can be connected to the NFC chip 302 through the feeding points.

[0119] Optionally, in actual application, a metal sheet and a metal coil may be used in combination in the second NFC antenna 306. Specifically, the metal coil may include a feeding point connected to the NFC chip 302, and the metal sheet may not include a feeding point.

[0120] Further optionally, in a circuit unit for implementing near field communication, the NFC antenna 306 includes a metal sheet (for example, Figure 8 The metal sheet 401 shown or Figure 9 On the basis of the metal sheet 402 shown in FIG. 4 , the second NFC antenna 306 may further include a metal coil. The metal coil may be located in the same plane as the metal sheet, and the metal coil may be located in an area surrounded by the bent metal sheet.

[0121] like Figure 10 As shown in , the metal coil 501 can be located in the area surrounded by the bent metal sheet 401. In practical applications, the NFC chip 302 can be further placed in the area surrounded by the metal coil 501.

[0122] Further alternatively, in a circuit unit for implementing near field communication, the NFC antenna 301 includes a metal sheet (for example, Figure 8 The metal sheet 401 shown or Figure 9 In the case of the metal sheet 402 shown in FIG. 1 , the second NFC antenna 306 may further include a metal coil, which may be arranged to overlap with the metal sheet; and the metal sheet may be closer to the scanned side of the device including the circuit unit than the metal coil.

[0123] like Figure 11 As shown in , the metal sheet 401 can be arranged closer to the scanned side of the device including the circuit unit than the metal coil 501.

[0124] In actual application, by looping or overlapping the metal sheet and the metal coil in the NFC antenna module (for example, the NFC antenna 301 or the second NFC antenna 306), the annular metal sheet can act as an amplifier, thereby improving the signal transmission efficiency and strength, thereby improving the success rate of waking up the user terminal device from the LPCD mode, and thereby improving the success rate of near-field communication.

[0125] The various technical features in the above embodiments can be arbitrarily combined as long as there is no conflict or contradiction between the combinations of features. However, due to space limitations, they are not described one by one. Therefore, the arbitrary combination of the various technical features in the above embodiments also falls within the scope of disclosure of this specification.

[0126] In one or more embodiments of this specification, an NFC device corresponding to the circuit unit for implementing near field communication is also provided. The NFC device may include any circuit unit provided in the embodiments of this specification as described above.

[0127] Specifically, the NFC device may include a circuit unit for implementing near field communication, and the circuit unit may include: an NFC antenna 301, an NFC chip 302 and an excitation circuit 303, the NFC chip 302 is connected to the NFC antenna 301, and the NFC chip 302 is connected to the excitation circuit 303.

[0128] The NFC chip 302 may be configured to obtain first energy when the NFC antenna 301 senses a radio frequency field of a user terminal device, and provide part of the first energy to the excitation circuit.

[0129] The excitation circuit 303 may be configured to generate and send an excitation signal using energy obtained from the NFC chip 302 , where the excitation signal is configured to excite the user terminal device to communicate with the NFC device.

[0130] In the embodiments of this specification, the NFC device operates in a passive mode, and the user terminal device communicating with the NFC device operates in an active mode.

[0131] It should be noted that the technical solution of the NFC device and the technical solution of the above-mentioned circuit unit belong to the same concept. For details not described in detail in the technical solution of the NFC device, please refer to the description of the technical solution of the above-mentioned circuit unit.

[0132] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments. The device provided in the embodiments of this specification includes an embodiment of a circuit unit for implementing near-field communication, so the device also has similar beneficial technical effects as the embodiment of the circuit unit for implementing near-field communication. Since the beneficial technical effects of the embodiment of the circuit unit for implementing near-field communication have been described in detail above, the beneficial technical effects of the corresponding device will not be repeated here.

[0133] The foregoing description describes specific embodiments of the present application. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims can be performed in an order different from that described in the embodiments and still achieve the desired results. Furthermore, the processes depicted in the accompanying drawings do not necessarily require the specific order shown or sequential order to achieve the desired results.

[0134] It should also be noted that the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a..." does not preclude the presence of other identical elements in the process, method, commodity, or apparatus comprising the element.

[0135] The foregoing is merely an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should all be included within the scope of the claims of the present application.

Claims

1. A circuit unit for implementing near-field communication, used in payment scenarios, and applied to an NFC tag or a payment terminal device. The circuit unit includes an NFC antenna, an NFC chip, and an excitation circuit. The NFC antenna is connected to the NFC chip, and the NFC chip is connected to the excitation circuit. The circuit unit also includes a sorting circuit, which is connected to the NFC antenna and the excitation circuit. The NFC chip is configured to obtain first energy when the NFC antenna senses the proximity of a radio frequency field of a user terminal device, and provide part of the first energy to the excitation circuit through an output voltage pin; The collating circuit is configured to obtain second energy when the NFC antenna senses the radio frequency field of the user terminal device, and provide at least part of the second energy to the excitation circuit; The excitation circuit is used to generate and send an excitation signal using the energy obtained from the NFC chip and the second energy. The excitation signal is used to excite the user terminal device in the low-power card detection mode to switch to the standard card detection mode and communicate with the device including the circuit unit.

2. The circuit unit according to claim 1, wherein The NFC antenna is connected to the excitation circuit; the excitation circuit is used to radiate the excitation signal to the user terminal device through the NFC antenna.

3. The circuit unit according to claim 1, further comprising a second NFC antenna, wherein the second NFC antenna is connected to the excitation circuit; and the excitation circuit is configured to radiate the excitation signal to the user terminal device through the second NFC antenna.

4. The circuit unit according to claim 1, wherein: The NFC chip is further configured to send an interrupt signal to the excitation circuit when the NFC antenna senses the radio frequency field of the user terminal device; The excitation circuit is specifically used to generate and send an excitation signal based on the signal characteristics of the interrupt signal when it is determined that the user terminal device is in a low-power card detection mode; the excitation signal is used to switch the user terminal device in the low-power card detection mode to the standard card detection mode.

5. The circuit unit according to claim 4, wherein: The excitation circuit includes a controller and a signal generator; The controller is configured to use energy obtained from the NFC chip and, based on a signal characteristic of the interrupt signal, determine whether the user terminal device is in a low-power card detection mode; and, if the user terminal device is in the low-power card detection mode, send a hardware enable signal to the signal generator; The signal generator is configured to generate and send the excitation signal in response to the hardware enable signal by utilizing energy obtained from the NFC chip. The circuit unit according to claim 5 , wherein: The controller is further configured to, using energy obtained from the NFC chip and based on flag information obtained from the NFC chip, determine whether communication between the user terminal device and the NFC chip is successful; and, when the user terminal device is in a low-power card detection mode and communication between the user terminal device and the NFC chip is unsuccessful, send a hardware enable signal to the signal generator.

7. The circuit unit according to claim 1, further comprising a tidying circuit, wherein the tidying circuit is connected to the NFC antenna and the excitation circuit; The sorting circuit is used to obtain second energy when the NFC antenna senses the radio frequency field of the user terminal device, and provide at least part of the second energy to the excitation circuit. 8 . The circuit unit according to claim 1 , further comprising an energy supply module, wherein the energy supply module is connected to the excitation circuit and is configured to provide a third energy to the excitation circuit. 9 . The circuit unit according to claim 1 , wherein the NFC antenna comprises a metal sheet, and the metal sheet is bent within a plane where the metal sheet is located so that both ends of the metal sheet along a length direction are close to each other and form a gap space. 10 . The circuit unit according to claim 9 , wherein both ends of the metal sheet along the length direction serve as feeding points of the NFC antenna.

11. The circuit unit according to claim 9, wherein the NFC antenna further comprises a metal coil, wherein the metal coil and the metal sheet are located in the same plane, and the metal coil is located in an area surrounded by the bent metal sheet.

12. The circuit unit according to claim 9, wherein the NFC antenna further comprises a metal coil, wherein the metal coil is arranged to overlap with the metal sheet; and the metal sheet is closer to a scanned side of the device including the circuit unit than the metal coil. 13 . The circuit unit according to claim 3 , wherein the second NFC antenna comprises a metal sheet, wherein the metal sheet is bent within a plane where the metal sheet is located so that both ends of the metal sheet along a length direction are close to each other and form a gap space. The circuit unit according to claim 13 , wherein both ends of the metal sheet along the length direction serve as feeding points of the second NFC antenna. 15 . The circuit unit according to claim 13 , wherein the second NFC antenna further comprises a metal coil, wherein the metal coil and the metal sheet are located in the same plane, and the metal coil is located in an area surrounded by the bent metal sheet.

16. The circuit unit according to claim 13, wherein the second NFC antenna further comprises a metal coil, wherein the metal coil is arranged to overlap with the metal sheet; and the metal sheet is closer to a scanned side of the device including the circuit unit than the metal coil. 17 . An NFC device, comprising the circuit unit according to claim 1 .

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