A near field communication device and system

Abstract

The application relates to the communication technical field, and discloses a near field communication device and system. The device comprises a microcontroller, a near field communication chip, a switching circuit, at least two groups of matching circuits and an antenna. The microcontroller is used for controlling the switching circuit to turn on the first matching circuit, sending a first operation instruction to the near field communication chip, and instructing the near field communication chip to send a first communication request to a near field communication tag. The microcontroller is also used for controlling the switching circuit to turn on the second matching circuit after the near field communication device determines that the communication with the near field communication tag is not successful. The microcontroller is also used for sending a second operation instruction to the near field communication chip, and instructing the near field communication chip to send a second communication request to the near field communication tag. The near field communication device provided by the embodiment of the application can establish communication with the near field communication tag by replacing the matching circuit in the radio frequency circuit, and can improve the communication success rate with the near field communication tag in different interference environments.

Description

Technical Field

[0001] This application relates to the field of communication technology, and in particular to a near-field communication device and system. Background Technology

[0002] In modern electronic product design, NFC (Near Field Communication) technology is widely used due to its convenient wireless data transmission capabilities. NFC technology allows electronic devices to exchange data over short distances and is commonly found in mobile payments, access control systems, data sharing, and other scenarios.

[0003] However, in practical applications, NFC communication is susceptible to interference in environments with electromagnetic fields. For example, in products that coexist with a switching power supply, such as air purifiers, the filter contains an NFC tag, and the filter is typically located close to the power supply. The NFC reader in the air purifier usually communicates with the NFC tag by emitting radio frequency signals to read information such as the filter's lifespan. However, because the NFC reader is too close to the power supply module, the electromagnetic radiation generated by the transformer in the power supply during operation can interfere with NFC communication. This interference can prevent the NFC reader from correctly demodulating the received signal, thus affecting the air purifier's ability to obtain information such as the filter's lifespan, reducing product performance and user experience.

[0004] In existing technologies, to address this issue, shielding materials are typically used to block interference sources, or structural designs are modified to keep the NFC reader away from interference sources. However, these methods suffer from high costs, complex manufacturing processes, and limited effectiveness. Therefore, finding a better solution to improve the success rate of communication between NFC readers and tags has become a pressing technical problem. Summary of the Invention

[0005] To address the aforementioned technical problems, this application provides a near-field communication device. This device establishes communication with a near-field communication tag by replacing the matching circuit in the radio frequency circuit, thereby increasing the probability of successful communication under different interference environments.

[0006] To achieve the above-mentioned technical objectives, this application provides the following technical solution:

[0007] In a first aspect, a near-field communication (NFC) device is provided, comprising: a microcontroller, a NFC chip, a switching circuit, at least two sets of matching circuits, and an antenna. The microcontroller controls the switching circuit to activate a first matching circuit. The microcontroller also sends a first operation instruction to the NFC chip, instructing the NFC chip to send a first communication request to a NFC tag using the first matching circuit and the antenna in the form of transmitting a first radio frequency signal, according to preset combination parameters. The microcontroller further controls the switching circuit to activate a second matching circuit after determining that the NFC chip has failed to complete communication with the NFC tag. The microcontroller also sends a second operation instruction to the NFC chip, instructing the NFC chip to send a second communication request to the NFC tag using the second matching circuit and the antenna in the form of transmitting a second radio frequency signal, according to preset combination parameters.

[0008] According to the first aspect, the antenna is used to receive the third radio frequency signal of the near-field communication tag's response, and returns the third radio frequency signal to the near-field communication chip through a matching circuit. The near-field communication chip is used to process the third radio frequency signal to obtain a first communication result, and returns the first communication result to the microcontroller.

[0009] According to the first aspect, or any implementation of the first aspect above, the near-field communication chip is also used to parse the response information sent by the near-field communication tag from the third radio frequency signal, verify the response information, and generate a first communication result after the response message is verified.

[0010] According to the first aspect, or any implementation of the first aspect above, the microcontroller is further configured to determine, after detecting the first communication result returned by the near-field communication chip, that the near-field communication device has successfully established communication with the near-field communication tag based on the content parsed from the first communication result.

[0011] According to the first aspect, or any implementation thereof, the microprocessor is further configured to send a third communication instruction to the near-field communication chip after determining that the near-field communication chip controls the first matching circuit and the antenna to transmit radio frequency signals according to the first preset combination parameters, and after determining that the near-field communication device has failed to establish communication with the near-field communication tag. The third communication instruction is used to instruct the near-field communication chip to change the preset combination parameters used, and to control the first matching circuit and the antenna to transmit radio frequency signals according to the changed preset combination parameters.

[0012] According to the first aspect, or any implementation of the first aspect above, the microcontroller is further configured to send a second operation instruction to the near-field communication chip after detecting that the near-field communication device has failed to establish communication with the near-field communication tag within a preset time period after sending the third communication instruction.

[0013] According to the first aspect, or any implementation of the first aspect above, the switching circuit includes a first control signal input terminal and a second control signal input terminal. The microcontroller is further configured to control the first control signal input terminal to send a high-level signal and control the second control signal input terminal to send a low-level signal, thereby enabling the switching circuit to conduct the first matching circuit. The microcontroller is also configured to control the first control signal input terminal to send a low-level signal and control the second control signal input terminal to send a high-level signal, thereby enabling the switching circuit to conduct the second matching circuit.

[0014] According to the first aspect, or any implementation of the first aspect above, the switching circuit includes a first control switch, a second control switch, a third control switch, and a fourth control switch. The first control signal input terminal is also used to connect the first control switch and the third control switch. The second control signal input terminal is also used to connect the second control switch and the fourth control switch. The switching circuit is further used to open the first control switch and the third control switch, thus activating the first matching circuit, after the microcontroller sends a high-level signal to the first control signal input terminal. The switching circuit is further used to close the second control switch and the fourth control switch, after the microcontroller sends a low-level signal to the first control signal input terminal. The switching circuit is further used to open the second control switch and the fourth control switch, thus activating the second matching circuit, after the microcontroller sends a high-level signal to the second control signal input terminal. The switching circuit is further used to close the first control switch and the third control switch, after the microcontroller sends a low-level signal to the second control signal input terminal. The first matching circuit includes a first sub-circuit and a third sub-circuit, and the second matching circuit includes a second sub-circuit and a fourth sub-circuit. The first sub-circuit, the second sub-circuit, the third sub-circuit, and the fourth sub-circuit include capacitors of different capacitance values.

[0015] In a second aspect, a communication system is provided, characterized in that it includes a near-field communication device and a near-field communication tag. The near-field communication device includes a microcontroller, a near-field communication chip, a switching circuit, at least two sets of matching circuits, and an antenna. The microcontroller is used to control the switching circuit to activate the first matching circuit. The microcontroller is used to send a first operation command to the near-field communication chip, the first operation command instructing the near-field communication chip to send a first communication request to the near-field communication tag in the form of transmitting a first radio frequency signal, according to preset combination parameters and using the first matching circuit and the antenna. The microcontroller is also used to control the switching circuit to activate the second matching circuit after the near-field communication device determines that communication with the near-field communication tag has not been successfully established. The microcontroller is also used to send a second operation command to the near-field communication chip, the second operation command instructing the near-field communication chip to send a second communication request to the near-field communication tag in the form of transmitting a second radio frequency signal, according to preset combination parameters and using the second matching circuit and the antenna. The near-field communication tag includes a second antenna and a second near-field communication chip. The second antenna is used to receive the radio frequency signal transmitted by the near-field communication device and transmit the radio frequency signal transmitted by the near-field communication device to the second near-field communication chip. The second near-field communication chip is used to analyze the radio frequency signals sent by the near-field communication device to obtain communication requests, including a first communication request, and / or a second communication request, and / or a third communication request. The second near-field communication chip is also used to verify the communication requests, determine whether communication has been established with the near-field communication device, and control the second antenna to send response information to the near-field communication device in the form of a third radio frequency signal. The antenna is used to send the third radio frequency signal to the near-field communication device.

[0016] Thirdly, an air purifier is provided for performing any of the implementations of the first aspect above, or any of the implementations of the second aspect above.

[0017] Fourthly, a circuit system is provided, the circuit system including a processing circuit configured to perform any of the implementations of the first aspect above.

[0018] Fifthly, a chip system is provided, including at least one processor and at least one interface circuit, wherein the at least one interface circuit is used to perform transceiver functions and send instructions to the at least one processor, and when the at least one processor executes instructions, the at least one processor executes any of the implementation methods of the first aspect above.

[0019] This application provides a near-field communication (NFC) device that transmits radio frequency (RF) signals to NFC tags by changing different matching circuits, enabling communication with NFC tags under various interference environments. This device effectively adapts to different electromagnetic interference environments without the need for shielding materials or modifications to the product's structural design, ensuring successful communication between the NFC reader and the tag. Attached Figure Description

[0020] To more clearly illustrate the technical solution of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 An air purifier including an NFC tag and an NFC reader is shown as an embodiment of this application;

[0022] Figure 2 This application illustrates a shielding material placement scheme according to an embodiment of the present application;

[0023] Figure 3 This application illustrates a structural design modification scheme provided by an embodiment of the present application;

[0024] Figure 4 This application illustrates a near-field communication device provided in an embodiment;

[0025] Figure 5 This application illustrates a further example of a near-field communication device provided in an embodiment of the present application;

[0026] Figure 6 This application illustrates another near-field communication device provided in an embodiment of the present application;

[0027] Figure 7 This application illustrates yet another near-field communication device provided in an embodiment of the present application;

[0028] Figure 8 A block diagram of a chip system provided in an embodiment of this application is shown. Detailed Implementation

[0029] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. Other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are all within the protection scope of this application.

[0030] In the following description, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0031] Furthermore, in this application, directional terms such as "upper," "lower," "inner," and "outer" are defined relative to the indicated placement of the components in the accompanying drawings. It should be understood that these directional terms are relative concepts, used for relative description and clarification, and can change accordingly depending on the placement of the components in the accompanying drawings.

[0032] Currently, NFC (Near Field Communication) technology is widely used in modern electronic products due to its convenient wireless data transmission capabilities. NFC technology allows electronic devices to exchange data over short distances. However, in practical applications, especially in products that coexist with switching power supplies, such as air purifiers, NFC readers are often affected by electromagnetic interference.

[0033] For example, Figure 1 An air purifier including an NFC tag and an NFC reader, as provided in an embodiment of this application, is illustrated. Figure 1 As shown, the air purifier contains a filter element as indicated by reference numeral 101, and an NFC tag as indicated by reference numeral 102 is attached to the filter element. The air purifier also includes an NFC card reader as indicated by reference numeral 103. Typically, a power supply module as indicated by reference numeral 104 is located below the NFC card reader.

[0034] NFC readers read the lifespan of the filter cartridge by communicating with NFC tags. Specifically, the NFC reader powers the NFC tag by emitting radio frequency signals and communicates with it. However, when the power supply module beneath the NFC reader is operating, its internal transformer generates electromagnetic radiation. Since the NFC reader is typically located close to the transformer, the electromagnetic waves generated by the transformer can interfere with the modulation waveform of the communication between the NFC reader and the NFC tag. This interference can cause the NFC reader to fail to correctly transmit data or to fail to properly demodulate the received tag's response signal, thus affecting accurate data transmission, reducing product performance, and impacting user experience.

[0035] Currently, there are two main solutions to this problem: shielding material solutions and structural design modification solutions.

[0036] Shielding material solutions: Figure 2 This illustration shows a shielding material placement scheme provided by an embodiment of this application. For example... Figure 2As shown, a transformer, as indicated by reference numeral 201, is installed on the switching power supply module indicated by reference numeral 104. The transformer, as indicated by reference numeral 201, is wrapped around a shielding material (such as ferrite absorbing material), as indicated by reference numeral 202. In some examples, the transformer is wrapped with a shielding material (such as ferrite absorbing material) to confine the radiated signal inside the transformer. In some examples, shielding material is placed on the structural components between the transformer and the NFC reader to reduce the penetration of interfering electromagnetic radiation. This weakens the interference of electromagnetic radiation caused by the transformer on the communication process between the NFC reader and the NFC tag, improving the success rate of communication between the NFC reader and the NFC tag.

[0037] However, this solution increases product costs, and in space-constrained situations, the installation location and effectiveness of the shielding material are limited, potentially failing to completely eliminate the aforementioned interference. For example, when installing the shielding material on the structural component between the switching power supply board and the NFC reader, the product structure may prevent finding a suitable installation location, or unevenness in the structure may increase production complexity and indirectly raise production costs during mass production. Furthermore, when the shielding material is placed on the transformer of the switching power supply, the high operating temperature of the transformer hinders heat dissipation, affecting the lifespan of the switching power supply.

[0038] Structural design modification plan: Figure 3 This illustration shows a structural design modification scheme provided by an embodiment of this application. For example... Figure 3 As shown, by changing the product structure design, the NFC card reader shown as reference numeral 103 is physically isolated from the switching power supply board shown as reference numeral 104 in order to reduce electromagnetic interference.

[0039] However, while this method can effectively reduce interference, it is difficult to implement for products already in mass production. For mass-produced products, the structural design and molds are finalized. Redesigning and manufacturing molds to move the power supply board away from the NFC reader would increase R&D and production costs. Moreover, due to limitations such as product performance, the distance between the power supply board and the NFC reader cannot be increased, or can only be increased slightly. This may not effectively solve the adverse interference of electromagnetic waves generated by the transformer on the power supply board during operation on NFC reader communication.

[0040] Therefore, a solution is needed to ensure the success rate of communication between NFC readers and NFC tags without using shielding materials or modifying the product's structural design.

[0041] This application provides a near-field communication device that establishes communication with a near-field communication tag by replacing the matching circuit in the radio frequency circuit. This allows communication with the near-field communication tag to be achieved under different interference environments.

[0042] To facilitate understanding of the embodiments of this application, the key terms appearing in the embodiments of this application will be explained below.

[0043] NFC (Near Field Communication): It is a short-range, high-frequency wireless communication technology that allows electronic devices to communicate and exchange data at very close range (usually within a few centimeters).

[0044] NFC Reader: In an NFC system, an NFC reader is a device that can transmit radio frequency signals and receive responses from NFC tags.

[0045] Tag: A tag is a passive device containing a chip and antenna that store information and is activated by a radio frequency signal sent by an NFC reader.

[0046] Transformer: In switching power supplies, transformers are used for voltage conversion, and they may generate electromagnetic radiation when they are working.

[0047] Electromagnetic Interference (EMI): Electromagnetic waves can interfere with electronic equipment and affect its normal operation.

[0048] Shielding materials: Materials used to reduce the impact of electromagnetic radiation, such as ferrite absorbing materials.

[0049] MCU (Microcontroller Unit): A microcontroller unit is an integrated circuit chip used to control embedded systems and execute programs to handle various tasks.

[0050] RF (Radio Frequency): Radio frequency refers to the frequency range of radio waves, which is usually used for wireless communication.

[0051] TX_Para: Transmission parameters refer to the configuration parameters of the NFC reader when transmitting radio frequency signals, such as transmission power.

[0052] RX_Para: Receive parameters refer to the configuration parameters of the NFC reader when receiving radio frequency signals, such as receive gain.

[0053] LC filter: A filter composed of an inductor (L) and a capacitor (C) used to filter harmonics in radio frequency signals to improve signal quality.

[0054] Electronic switch circuit: A switch implemented using electronic components (such as transistors, MOSFETs, etc.) to control the connection or disconnection of a circuit.

[0055] Transistor: A semiconductor device used to amplify or switch electronic signals.

[0056] MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor): A type of field-effect transistor used to control the flow of current.

[0057] I2C interface (12C_SCL, 12C_SDA): A serial communication bus interface used between microcontrollers and other integrated circuits.

[0058] Firmware: Software in an embedded system, typically stored in non-volatile memory, used to control the operation of hardware devices.

[0059] Radio frequency (RF) parameters: These are various parameters related to the transmission and reception of radio frequency signals, such as frequency, power, and modulation method.

[0060] RF matching circuit: A circuit used to generate, filter, amplify, or modulate radio frequency (RF) signals. The main function of a matching circuit is to optimize the transmission efficiency of RF signals, ensuring effective signal transmission between different parts of the circuit while reducing signal reflection and loss. RF matching typically involves impedance matching and bandwidth adjustment.

[0061] LC filter: A filter consisting of an inductor (L) and a capacitor (C) used to filter specific frequency components in a signal.

[0062] Antenna Coil: Antennas are used to transmit and receive radio frequency signals.

[0063] Resonant frequency: The frequency at which a circuit or system reaches its maximum response or minimum impedance at a specific frequency.

[0064] Impedance matching: In wireless communication, ensuring impedance matching between the transmitter and antenna or between the antenna and receiver is crucial for maximizing power transfer.

[0065] In some embodiments, Figure 4 An embodiment of this application provides a near-field communication device. For example... Figure 4 As shown, the near-field communication device includes, as Figure 4 The microcontroller shown by reference numeral 401 in the attached figure, such as Figure 4 The near-field communication chip shown by reference numeral 402 in the attached figure, such as Figure 4 The switching circuit shown by reference numeral 403 in the attached figure, such as Figure 4 At least two sets of matching circuits as shown by reference numeral 404 in the attached figure, such as Figure 4 The antenna shown by reference numeral 404 in the attached figure.

[0066] For example, Figure 5 This illustration shows a further example of a near-field communication device provided in an embodiment of this application. For example... Figure 5 As shown, this near-field communication device is an NFC card reader. Figure 5 The figure in the middle, reference numeral 501, illustrates a microcontroller (Control MCU). Figure 5 The figure in the middle, reference numeral 502, shows a near field communication chip (NFC Reader IC). Figure 5 Figure 503 shows a two-way filter. Figure 5 Figure 504 in the figure illustrates a matching circuit. Figure 5 Figure 505 in the figure shows an antenna.

[0067] The microcontroller (Control MCU) shown in Figure 501 includes VCC, I2C_SCL, I2C_SDA, CTRL1, and CTRL2. VCC is the voltage input terminal used to provide power to the near-field communication (NFC) device. I2C_SCL is the clock signal pin used for communication between the Control MCU and the NFC Reader IC. I2C_SDA is the data signal pin used for communication between the Control MCU and the NFC Reader IC. CTRL1 and CTRL2 are control pins used to control the switching of different matching circuits in the NFC device. The high or low level state of CTRL1 and / or CTRL2 determines the specific matching circuit that is activated.

[0068] The near-field communication (NFC) reader IC, shown by reference numeral 502, includes I2C_SCL, I2C_SDA, TX1, TX2, RX, and VMID. I2C_SCL is the clock signal pin used for communication between the microcontroller (Control MCU) and the NFC reader IC. I2C_SDA is the data signal pin used for communication between the microcontroller (Control MCU) and the NFC reader IC. TX1 and TX2 are the differential RF signal outputs of the NFC reader IC. RX is the receive signal pin, used to receive the RF signal returned from the matching circuit and received from the NFC tag. VMID is the midpoint voltage, used to provide a stable voltage reference for the NFC reader IC to ensure its normal operation. The NFC reader IC also includes an RF parameter register. The RF parameter register is mainly used to store and configure the RF-related parameters of the NFC reader IC. The first or second operation instruction sent by the microcontroller to the NFC reader IC carries different preset combinations of parameters. After receiving different preset combination parameters carried in the first or second operation instruction, the near-field communication chip can configure the radio frequency related parameters in the radio frequency parameter register according to the different preset combination parameters.

[0069] The two filters shown in Figure 503 include two LC filters composed of L1 and C1, and L2 and C2. The differential RF signals TX1 and TX2 sent by the near-field communication chip to the switching circuit pass through these two LC filters. These two LC filters can filter out harmonics in the TX1 and TX2 differential RF signals. The circuit structure shown in Figure 503 also includes resistor R3, capacitor C3, resistor R4, capacitor C4, and other circuit components.

[0070] The matching circuit shown in the attached drawing 504 includes a first matching circuit and a second matching circuit.

[0071] The antenna shown by reference numeral 505 is used to send radio frequency signals to the near-field communication tag and to receive radio frequency signals sent by the near-field communication tag (such as an NFC tag), and to return the radio frequency signals to the near-field communication chip through a matching circuit.

[0072] In some embodiments, the microcontroller is configured to control the switching circuit to activate the first matching circuit. The microcontroller is also configured to send a first operation instruction to the near-field communication chip, instructing the near-field communication chip to send a first communication request to the near-field communication tag using the first matching circuit and an antenna in the form of transmitting a first radio frequency signal, according to preset combination parameters. The microcontroller is further configured to control the switching circuit to activate the second matching circuit after determining that the near-field communication chip has failed to complete communication with the near-field communication tag. The microcontroller is also configured to send a second operation instruction to the near-field communication chip, instructing the near-field communication chip to send a second communication request to the near-field communication tag using the second matching circuit and an antenna in the form of transmitting a second radio frequency signal, according to preset combination parameters.

[0073] In some examples, after determining that the near-field communication chip has failed to communicate with the near-field communication tag, the microcontroller improves the success rate of the communication process by switching the matching circuit. In some examples, the reasons why the near-field communication chip may fail to communicate with the near-field communication tag could be varied. For example, the communication process may be interfered with by electromagnetic field signals, causing the near-field communication device to fail to transmit the first radio frequency signal. Or, after the near-field communication device successfully transmits the first radio frequency signal, the near-field communication tag fails to recognize the first radio frequency signal. Or, the near-field communication device may fail to receive or recognize the near-field communication tag's response signal, etc.

[0074] For example, such as Figure 5 As shown in the attached figure, the microcontroller, as indicated by reference numeral 501, communicates with the near-field communication (NFC) chip, as indicated by reference numeral 502, via I2C_SCL, I2C_SDA, and sends a first operation command to the NFC chip. The NFC chip supports the NFC protocol and, after parsing the first operation command, can generate a first radio frequency (RF) signal according to the protocol content. The NFC chip transmits the first RF signal to the matching circuit, as indicated by reference numeral 504, through its TX1 and TX2 pins. The first RF signal includes differential TX1 and TX2 RF signals. After being filtered by two filters, as indicated by reference numeral 503, the first RF signal is transmitted to the first switching circuit and the antenna. These two filters, the matching circuit, and the antenna jointly adjust the impedance at the output terminal. The antenna is used to transmit the first RF signal, providing power to the NFC tag for waking up or activating it. Thus, the NFC device sends a first communication request to the NFC tag. The first communication request is used to request access to the information stored in the NFC tag.

[0075] In some embodiments, the antenna is used to receive a third radio frequency signal from a near-field communication tag response, and returns the third radio frequency signal to the near-field communication chip through a matching circuit. The near-field communication chip is used to process the third radio frequency signal to obtain a first communication result, and returns the first communication result to the microcontroller.

[0076] For example, the antenna is transmitted via, as Figure 5 The RX receive signal pin, indicated by reference numeral 503 in the attached diagram, sends a third radio frequency signal to the near-field communication chip. The near-field communication chip processes the third radio frequency signal to obtain a first communication result, and sends the first communication result to the microcontroller through the clock signal pin 12C_SCL and the data signal pin 12C_SDA.

[0077] In some embodiments, the near-field communication chip is further configured to parse the response information sent by the near-field communication tag from the third radio frequency signal, verify the response information, and generate a first communication result after the response message is verified.

[0078] In some examples, the near-field communication chip can perform preliminary verification of the response information to obtain a first communication result. This first communication result is then sent to the microcontroller.

[0079] For example, the near-field communication (NFC) chip demodulates the received radio frequency (RF) signal. Based on magnetic field coupling, NFC technology transmits information through RF signal modulation and demodulation. The NFC chip uses demodulation technology to reconstruct the response information sent by the NFC tag. The NFC chip can also further decode the demodulated signal to extract the information stored in the NFC tag.

[0080] In some embodiments, the microcontroller is further configured to determine, based on the first communication result returned by the near-field communication chip, that the near-field communication device has successfully established communication with the near-field communication tag.

[0081] For example, the microcontroller can further verify the first communication result by reading the data decoded by the near-field communication chip and further processing it to determine the communication status between the near-field communication device and the near-field communication chip.

[0082] In some embodiments, the microcontroller is further configured to parse the first communication result to obtain a communication status value, which indicates that the near-field communication device has successfully established communication with the near-field communication tag. Alternatively, the microcontroller is further configured to parse the first communication result to obtain tag information, and to verify the tag information. Upon successful verification, it is determined that the near-field communication device has successfully established communication with the near-field communication tag. The tag information is the tag information of the near-field communication tag carried in the response information. The tag information may include the ID of the near-field communication tag, stored data, etc. The stored data includes the lifespan of the near-field communication tag, etc.

[0083] In some embodiments, if the microcontroller determines that the near-field communication device has failed to establish communication with the near-field communication tag after controlling the near-field communication device to complete the above process, it will send a third communication command to the near-field communication chip. That is, after determining that the near-field communication chip controls the first matching circuit and the antenna to transmit radio frequency signals according to the first preset combination parameters, and then determines that the near-field communication device has failed to establish communication with the near-field communication tag, the microprocessor sends a third communication command to the near-field communication chip.

[0084] In some examples, the third communication command instructs the near-field communication chip to change the preset combination parameters used, and controls the first matching circuit and antenna to transmit radio frequency signals according to the changed preset combination parameters. The first communication command carries the first preset combination parameters. The third communication command carries preset combination parameters that are different from the first preset combination parameters. In some examples, the preset combination parameters refer to the parameters used when the near-field communication device communicates with the near-field communication tag. In order to achieve communication between the near-field communication device and the near-field communication tag under different electromagnetic radiation environments, the microcontroller of the near-field communication device can be configured with multiple sets of preset combination parameters as needed. After the microprocessor instructs the near-field communication chip to control the first matching circuit and antenna to transmit radio frequency signals according to the first preset combination parameters, if it determines that the near-field communication device has failed to establish communication with the near-field communication tag, the microcontroller can send a third communication command carrying other preset combination parameters to the near-field communication chip, instructing the near-field communication chip to change to other preset combination parameters to communicate with the tag. Subsequently, without replacing the matching circuit, the microprocessor can continue to send other preset combination parameters to the near-field communication chip, causing the near-field communication chip to continue to change other preset combination parameters to communicate with the near-field communication tag, until all preset combination parameters have been traversed.

[0085] In some examples, the preset combination parameters include transmit and receive parameters. The transmit parameters are used to set the transmit power of the radio frequency (RF) signal generated by the near-field communication (NFC) device. The receive parameters are used to set the receive gain of the RF signals that the NFC device can receive. The RF parameter registers inside the NFC chip can be divided into transmit and receive categories. The transmit registers store the transmit parameters, and the receive registers store the receive parameters. When the NFC device fails to establish communication with the NFC tag, the microcontroller adjusts the values ​​in the RF parameter registers to switch the preset combination parameters used by the first matching circuit.

[0086] For example, Table 1 below shows one possible transmit and receive parameters.

[0087] launch parameters Receive parameters TX_Para1 RX_Para1 TX_Para2 RX_Para2

[0088] Table 1

[0089] Table 2 below shows one preset combination of parameters. As shown in Table 2, the transmit parameters include TX_Para1 and TX_Para2. The receive parameters include RX_Para1 and RX_Para2. Combining these four parameters can form four sets of preset combination parameters as shown in Table 2 below.

[0090] combination launch parameters Receive parameters 1 TX_Para1 RX_Para1 2 TX_Para1 RX_Para2 3 TX_Para2 RX_Para1 4 TX_Para2 RX_Para2

[0091] Table 2

[0092] For example, the parameter switching process includes the following steps S1 to S4:

[0093] S1. The microcontroller instructs the near-field communication chip to control the first matching circuit and antenna to transmit radio frequency signals according to the parameters of combination 1 (i.e., the transmission parameter is TX_Para1 and the reception parameter is RX_Para1) to communicate with the near-field communication tag.

[0094] S2. If the near-field communication device and the near-field communication tag fail to establish communication, the microcontroller instructs the near-field communication chip to control the first matching circuit and the antenna to transmit radio frequency signals according to the combined 2 parameters (transmit parameter is TX_Para1, and receive parameter is RX_Para2).

[0095] If the near-field communication device and the near-field communication tag successfully establish communication in step S1, the microcontroller will not instruct the user to change the combination parameters.

[0096] S3. If the near-field communication device and the near-field communication tag fail to establish communication, the microcontroller instructs the near-field communication chip to control the first matching circuit and the antenna to transmit radio frequency signals according to the combined 3 parameters (the transmission parameter is TX_Para2 and the reception parameter is RX_Para1).

[0097] If the near-field communication device and the near-field communication tag successfully establish communication in step S2, the microcontroller will not instruct the user to change the combination parameters.

[0098] S4. If the near-field communication device and the near-field communication tag fail to establish communication, the microcontroller instructs the near-field communication chip to control the first matching circuit and the antenna to transmit radio frequency signals according to the combined 4 parameters (the transmission parameter is TX_Para2 and the reception parameter is RX_Para2).

[0099] If the near-field communication device and the near-field communication tag successfully establish communication in step S3, the microcontroller does not instruct the near-field communication chip to change the combination parameters.

[0100] In this way, by changing different preset combination parameters, the near-field communication device can transmit radio frequency signals to the near-field communication tag, thereby increasing the success rate of communication between the near-field communication device and the near-field communication tag without changing the matching circuit.

[0101] In some possible implementations, the near-field communication (NFC) chip configures the values ​​in the radio frequency (RF) parameter register according to the preset combination parameters carried in the instructions sent by the microcontroller. This allows for switching the RF-related parameters used to transmit the RF signal, resulting in fast switching speed, low switching cost, and high efficiency. Therefore, in this embodiment, after determining that the NFC chip has failed to communicate with the NFC tag, the microcontroller first attempts to switch the preset combination parameters to complete the communication with the NFC tag. Only when the microcontroller fails to successfully complete the communication with the NFC tag using multiple sets of preset combination parameters does it switch the matching circuit used to transmit the RF signal.

[0102] In some embodiments, the microcontroller is further configured to send a second operation instruction to the near-field communication chip after detecting that the near-field communication device has failed to establish communication with the near-field communication tag within a preset time period after sending the third communication instruction. The second operation instruction is used to instruct the near-field communication chip to replace the matching circuit used. That is, the microcontroller replaces the matching circuit only after the near-field communication chip has traversed all preset combination parameters and still cannot successfully establish communication with the near-field communication tag.

[0103] Therefore, in this embodiment, the near-field communication device prioritizes increasing the success rate of communication between the near-field communication device and the near-field communication tag by changing preset combination parameters. If successful communication between the near-field communication device and the near-field communication tag is not achieved after changing multiple sets of preset combination parameters, the matching circuit used is then switched. This approach can improve the success rate of communication between the near-field communication device and the near-field communication tag in a low-cost and highly efficient manner.

[0104] In some possible implementations, the communication environment between the near-field communication device (NFC) and the NFC tag may experience interference signals due to factors such as transformers. Replacing the matching circuit of the NFC device allows for adjustments to the RF circuit parameters, optimizing RF signal transmission and reducing the impact of environmental interference. This improves the communication stability between the NFC device and the NFC tag, increasing the communication success rate.

[0105] In other possible implementations, one function of the matching circuit is to perform impedance matching, ensuring that the impedance of the near-field communication device's antenna matches the input impedance of the near-field communication chip. In some examples, if the near-field communication device has only one fixed circuit, its communication with the near-field communication tag may not be able to adapt to different external electromagnetic interference environments.

[0106] In other examples, placing different near-field communication (NFC) tags within the electromagnetic field generated by the matching circuit and antenna of the NFC device can cause changes in the impedance of the antenna within the NFC device, making it impossible to maintain a stable operating state. Therefore, in this embodiment, by setting multiple sets of matching circuits in the NFC device, the chances of the NFC reader antenna communicating with different tags at a better impedance can be increased, thereby increasing the communication success rate between the NFC device and the NFC tags. The following describes the process of switching matching circuits in the NFC device provided in this embodiment.

[0107] In some embodiments, the switching circuit includes at least two control signal inputs. The microcontroller is also configured to send different level signals through the control signal inputs, causing the switching circuit to activate different matching circuits.

[0108] In some embodiments, the switching circuit includes a first control signal input terminal and a second control signal input terminal. The microcontroller is further configured to control the first control signal input terminal to send a high-level signal and control the second control signal input terminal to send a low-level signal, thereby enabling the switching circuit to conduct the first matching circuit. The microcontroller is also configured to control the first control signal input terminal to send a low-level signal and control the second control signal input terminal to send a high-level signal, thereby enabling the switching circuit to conduct the second matching circuit.

[0109] In some embodiments, the first matching circuit includes a first sub-circuit and a third sub-circuit, and the second matching circuit includes a second sub-circuit and a fourth sub-circuit.

[0110] For example, Figure 6 This illustration shows another near-field communication device provided in an embodiment of this application. The following describes... Figure 6 The above example illustrates the control signal input terminals and sub-circuits.

[0111] Figure 6 The switching circuit shown by reference numeral 601 in the attached figure includes a control pin CTRL1 (first control signal input terminal) and a control pin CTRL2 (second control signal input terminal). Control pins CTRL1 and CTRL2 are used by the microcontroller to send high-level or low-level signals to the switching circuit, thereby switching the matching circuit.

[0112] Figure 6 Reference numeral 602 in the accompanying drawing shows four matching circuits: matching circuit A1 (first sub-circuit), matching circuit A2 (second sub-circuit), matching circuit B1 (third sub-circuit), and matching circuit B2 (fourth sub-circuit). Matching circuit A1 (first sub-circuit) and matching circuit B1 (third sub-circuit) constitute the first matching circuit. Matching circuit A2 (second sub-circuit) and matching circuit B2 (fourth sub-circuit) constitute the second matching circuit.

[0113] As shown in Table 3 below, the microcontroller controls CTRL1 to send a high-level signal and CTRL2 to send a low-level signal, which enables the switching circuit to connect TX1_A and matching circuit A1, and TX2_B and matching circuit B1. The microcontroller controls CTRL1 to send a low-level signal and CTRL2 to send a high-level signal, which enables the switching circuit to connect TX1_A and matching circuit A2, and TX2_B and matching circuit B2.

[0114] Control signal status Matching circuit with TX1_A conducting Matching circuit with TX2_B conducting CTRL1 high level, CTRL2 low level Matching circuit A1 Matching circuit B1 CTRL1 low level, CTRL2 high level Matching circuit A2 Matching circuit B2

[0115] Table 3

[0116] In some embodiments, the switching circuit includes a first control switch, a second control switch, a third control switch, and a fourth control switch. A first control signal input terminal is also used to connect the first control switch and the third control switch. A second control signal input terminal is also used to connect the second control switch and the fourth control switch. The switching circuit is further configured to turn on the first control switch and the third control switch after the microcontroller sends a high-level signal to the first control signal input terminal. The switching circuit is further configured to turn off the second control switch and the fourth control switch after the microcontroller sends a low-level signal to the first control signal input terminal. The switching circuit is further configured to turn on the second control switch and the fourth control switch after the microcontroller sends a high-level signal to the second control signal input terminal. The switching circuit is further configured to turn off the first control switch and the third control switch after the microcontroller sends a low-level signal to the first control signal input terminal.

[0117] For example, Figure 7 This application illustrates another further demonstration of a near-field communication device provided in an embodiment of the present application. Figure 7 Reference numeral 701 in the figure illustrates a switching circuit. In the switching circuit shown by reference numeral 701, CTRL1 is the first control signal input terminal. CTRL2 is the second control signal input terminal. Transistor Q1 is the first control switch. Transistor Q2 is the second control switch. Transistor Q3 is the third control switch. Transistor Q4 is the fourth control switch. CTRL1 is used to connect Q1 and Q3. CTRL2 is used to connect Q2 and Q4.

[0118] For example, after CTRL1 sends a high-level signal, Q1 and Q3 are turned on, and A1 is turned on. After CTRL2 sends a low-level signal, Q2 and Q4 are turned off. After CTRL2 sends a high-level signal, Q1 and Q3 are turned on. After CTRL1 sends a low-level signal, Q1 and Q3 are turned off.

[0119] In this way, the microcontroller can easily control the switching circuit by sending a high-level signal or a low-level signal at the control signal input terminal.

[0120] In some embodiments, the first sub-circuit, the second sub-circuit, the third sub-circuit, and the fourth sub-circuit include capacitors with different capacitance values.

[0121] In some embodiments, the switching circuit is further configured to activate the first matching circuit when the first control switch and the third control switch are turned on, including: the switching circuit is further configured to activate the first sub-circuit when the first control switch is turned on and the third sub-circuit when the third control switch is turned on. The switching circuit is further configured to activate the second matching circuit when the second control switch and the fourth control switch are turned on, including: the switching circuit is further configured to activate the second sub-circuit when the second control switch is turned on and the fourth sub-circuit when the fourth control switch is turned on.

[0122] In some embodiments, the first control switch, the second control switch, the third control switch, and the fourth control switch include transistors and / or MOSFETs, which are used to turn on different sub-circuits.

[0123] This allows the first matching circuit composed of A1 and B1 to be activated.

[0124] For example, Figure 7 Figure 702 shows four matching circuits. In the matching circuit shown by figure 702, capacitors C5 and C6 form the first sub-circuit. Capacitors C7 and C8 form the second sub-circuit. Capacitors C9 and C10 form the third sub-circuit. Capacitors C11 and C12 form the fourth sub-circuit. The switching circuit can conduct the first sub-circuit when the first control switch (transistor Q1) is turned on. The switching circuit can conduct the third sub-circuit when the third control switch (transistor Q3) is turned on. The switching circuit can conduct the second sub-circuit when the second control switch (transistor Q2) is turned on. The switching circuit can conduct the fourth sub-circuit when the second control switch (transistor Q4) is turned on. Thus, when transistors Q1 and Q3 are turned on, the switching circuit can conduct the first matching circuit composed of the first and third sub-circuits. When transistors Q2 and Q4 are turned on, the switching circuit can conduct the second matching circuit composed of the second and fourth sub-circuits.

[0125] In this way, the switching structure set in the switching circuit can easily and flexibly realize the switching of the matching circuit.

[0126] This application also provides a near-field communication system, which includes a near-field communication device and a near-field communication tag. (The above is in conjunction with...) Figures 4-7This application describes a near-field communication (NFC) device provided in its embodiments. In some examples, the NFC tag includes a second antenna and a second NFC chip. The second antenna receives radio frequency (RF) signals transmitted by the NFC device and transmits these RF signals to the second NFC chip. The second NFC chip parses the RF signals transmitted by the NFC device to obtain communication requests, which may include a first communication request, and / or a second communication request, and / or a third communication request. The second NFC chip also verifies the communication requests, determines that communication has been established with the NFC device, and controls the second antenna to send a response signal to the NFC device in the form of a third RF signal. The antenna is used to send the third RF signal to the NFC device.

[0127] This application also provides an NFC card reader for performing the functions of the above-described near-field communication device.

[0128] This application also provides an air purifier, including the above-mentioned near-field communication device and / or the above-mentioned near-field communication system.

[0129] This application also provides a chip system. Figure 8 A block diagram of a chip system provided in an embodiment of this application is shown.

[0130] See Figure 8 As shown, the chip system includes at least one processor 801 and at least one interface circuit 802. The processor 801 and the interface circuit 802 are interconnected via lines. For example, the interface circuit 802 can be used to receive signals from other devices (e.g., the memory of an electronic device). As another example, the interface circuit 802 can be used to send signals to other devices. Exemplarily, the interface circuit can read instructions stored in the memory and send those instructions to the processor 801. When the instructions are executed by the processor 801, the electronic device can perform the steps in the above embodiments. Of course, the chip system may also include other discrete components, which are not specifically limited in this application embodiment.

[0131] This application also provides a computer-readable storage medium including computer instructions that, when executed on the near-field communication device, cause the near-field communication device to perform various functions or steps performed by the near-field communication device in the above method embodiments.

[0132] Through the above description of the embodiments, those skilled in the art will clearly understand that, for the sake of convenience and brevity, the division of the above functional modules is only used as an example. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0133] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For example, the division of modules or units is merely a logical functional division, and there may be other division methods in actual implementation. For example, multiple units or components may be combined or integrated into another device, or some features may be ignored or not executed. Furthermore, the mutual coupling or direct coupling or communication connection shown or discussed may be through some interfaces, and the indirect coupling or communication connection of devices or units may be electrical, mechanical, or other forms.

[0134] The units described as separate components may or may not be physically separate. A component shown as a unit can be one or more physical units; that is, it can be located in one place or distributed in multiple different locations. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0135] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0136] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a readable storage medium. Based on this understanding, the technical solutions of the embodiments of this application, in essence, or the parts that contribute to the prior art, or all or part of the technical solutions, can be embodied in the form of a software product. This software product is stored in a storage medium and includes several instructions to cause a device (which may be a microcontroller, chip, etc.) or processor to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0137] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions within the technical scope disclosed in this application should be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0138] It should be noted that those skilled in the art, upon considering the specification and practicing the application disclosed herein, will readily conceive of other embodiments of this application. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and embodiments are to be considered exemplary only, and the true scope of this application is indicated by the claims.

[0139] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A near-field communication device, characterized in that, include: Microcontroller, near-field communication chip, switching circuit, at least two sets of matching circuits, antenna; The microcontroller is used to control the switching circuit to turn on the first matching circuit; The microcontroller is used to send a first operation instruction to the near-field communication chip. The first operation instruction is used to instruct the near-field communication chip to send a first communication request to the near-field communication tag in the form of sending a first radio frequency signal according to a preset combination parameter and using a first matching circuit and an antenna. The microcontroller is also configured to control the switching circuit to activate the second matching circuit after determining that the near-field communication chip has failed to complete communication with the near-field communication tag; The microcontroller is also used to send a second operation instruction to the near-field communication chip, the second operation instruction being used to instruct the near-field communication chip to send a second communication request to the near-field communication tag in the form of sending a second radio frequency signal, according to a preset combination parameter and using a second matching circuit and the antenna.

2. The apparatus according to claim 1, characterized in that, The antenna is used to receive the third radio frequency signal of the near-field communication tag response and return the third radio frequency signal to the near-field communication chip through a matching circuit; The near-field communication chip is used to process the third radio frequency signal to obtain a first communication result, and then returns the first communication result to the microcontroller.

3. The apparatus according to claim 2, characterized in that, The near-field communication chip is also used to parse the response information sent by the near-field communication tag from the third radio frequency signal, verify the response information, and generate the first communication result after the response message is verified.

4. The apparatus according to claim 3, characterized in that, The microcontroller is also configured to, after detecting the first communication result returned by the near-field communication chip, determine, based on the content parsed from the first communication result, that the near-field communication device has successfully established communication with the near-field communication tag.

5. The apparatus according to claim 4, characterized in that, The microprocessor is further configured to send a third communication instruction to the near-field communication chip after determining that the near-field communication chip controls the first matching circuit and the antenna to transmit radio frequency signals according to the first preset combination parameters, and after determining that the near-field communication device has failed to establish communication with the near-field communication tag; the third communication instruction is used to instruct the near-field communication chip to change the preset combination parameters and control the first matching circuit and the antenna to transmit radio frequency signals according to the changed preset combination parameters.

6. The apparatus according to claim 5, characterized in that, The microcontroller is also configured to send the second operation command to the near-field communication chip within a preset time period after sending the third communication command, after detecting that the near-field communication device has failed to establish communication with the near-field communication tag.

7. The apparatus according to claim 6, characterized in that, The switching circuit includes a first control signal input terminal and a second control signal input terminal; The microcontroller is also used to control the first control signal input terminal to send a high-level signal and control the second control signal input terminal to send a low-level signal, so that the switching circuit turns on the first matching circuit; The microcontroller is also used to control the first control signal input terminal to send a low-level signal and control the second control signal input terminal to send a high-level signal, so that the switching circuit turns on the second matching circuit.

8. The apparatus according to claim 7, characterized in that, The switching circuit includes a first control switch, a second control switch, a third control switch, and a fourth control switch; The first control signal input terminal is also used to connect the first control switch and the third control switch; the second control signal input terminal is also used to connect the second control switch and the fourth control switch; The switching circuit is also used to turn on the first control switch and the third control switch and conduct the first matching circuit after the microcontroller controls the first control signal input terminal to send a high-level signal. The switching circuit is also used to turn off the second control switch and the fourth control switch after the microcontroller sends a low-level signal to the first control signal input terminal. The switching circuit is also used to turn on the second control switch and the fourth control switch and conduct the second matching circuit after the microcontroller controls the second control signal input terminal to send a high-level signal; The switching circuit is also used to turn off the first control switch and the third control switch after the microcontroller sends a low-level signal at the second control signal input terminal. The first matching circuit includes a first sub-circuit and a third sub-circuit, and the second matching circuit includes a second sub-circuit and a fourth sub-circuit. The first sub-circuit, the second sub-circuit, the third sub-circuit, and the fourth sub-circuit include capacitors with different capacitance values.

9. A communication system, characterized in that, Including near-field communication devices and near-field communication tags; The near-field communication device includes a microcontroller, a near-field communication chip, a switching circuit, at least two sets of matching circuits, and an antenna; The microcontroller is used to control the switching circuit to turn on the first matching circuit; The microcontroller is used to send a first operation instruction to the near-field communication chip. The first operation instruction is used to instruct the near-field communication chip to send a first communication request to the near-field communication tag in the form of sending a first radio frequency signal according to a preset combination parameter and using a first matching circuit and an antenna. The microcontroller is also configured to control the switching circuit to activate the second matching circuit after the near-field communication device determines that the near-field communication chip has failed to complete communication with the near-field communication tag; The microcontroller is also used to send a second operation instruction to the near-field communication chip, the second operation instruction being used to instruct the near-field communication chip to send a second communication request to the near-field communication tag in the form of sending a second radio frequency signal according to a preset combination parameter using a second matching circuit and the antenna; The near-field communication tag includes a second antenna and a second near-field communication chip; The second antenna is used to receive the radio frequency signals sent by the near-field communication device and transmit the radio frequency signals sent by the near-field communication device to the second near-field communication chip; The second near-field communication chip is used to parse the radio frequency signals sent by the near-field communication device to obtain communication requests, the communication requests including the first communication request, and / or the second communication request, and / or the third communication request; The second near-field communication chip is also used to verify the communication request, determine that communication has been established with the near-field communication device, and control the second antenna to send response information to the near-field communication device in the form of a third radio frequency signal; The antenna is used to transmit a third radio frequency signal to the near-field communication device.

10. An air purifier, characterized in that, include: The apparatus as described in any one of claims 1-8, or the system as described in claim 9.

Images