Near field communication method, module, equipment, medium and product

Abstract

The embodiment of the invention provides a near field communication method, a module, equipment, a medium and a product. The method comprises the following steps: acquiring a first radio frequency signal sent by a main device of near field communication; judging whether the first radio frequency signal is a low-power-consumption signal or not; if the first radio-frequency signal is a low-power-consumption signal, selecting a first target modulated radio-frequency signal matched with the first radio-frequency signal from a plurality of modulated radio-frequency signals; and transmitting the first target modulation radio frequency signal of a first preset duration so as to promote the master device to exit a low-power-consumption mode.

Description

Technical Field

[0001] This specification relates to the field of near-field communication technology, and particularly to a method for near-field communication. This specification also relates to a near-field communication module, a near-field communication device, a computing device, a computer-readable storage medium, and a computer program product. Background Technology

[0002] With the continuous development of computer technology, Near Field Communication (NFC) technology has been widely applied in various scenarios due to its convenience, security, and broad device compatibility. These include payment scenarios, access control scenarios, and turnstile scenarios. In everyday consumption environments such as retail stores, public transportation, vending machines, and restaurants, users can use NFC-enabled smartphones, smartwatches, or other wearable devices to perform fast, contactless payment transactions.

[0003] LPCD (Low) Power Card Detection (LPCD) mode is a power-saving mechanism in the NFC controller to reduce power consumption. It detects the presence of cards or card-simulated devices by periodically emitting radio frequency signals. When LPCD is enabled, the NFC controller only performs polling operations after detecting a proximity event, thereby significantly reducing overall power consumption and improving device battery life and user experience.

[0004] In practical applications, due to the different NFC controller chips used by different smartphones, the different wake-up strategies of LPCD mode, and the different antenna positions and shapes, some phones cannot exit LPCD mode when they are close to external devices, which leads to communication failure.

[0005] Therefore, how to encourage devices such as smartphones to exit LPCD mode, ensure communication stability, and improve user experience is an urgent technical problem to be solved. Summary of the Invention

[0006] In view of this, one or more embodiments of this specification provide a method, module, device, medium, and product for near-field communication to improve the stability of near-field communication.

[0007] According to a first aspect of one or more embodiments of this specification, a near-field communication method is provided, applied to a slave device of near-field communication, comprising: acquiring a first radio frequency signal emitted by a master device of near-field communication; determining whether the first radio frequency signal is a low-power signal; the low-power signal being a radio frequency signal emitted by the master device in a low-power mode; if the first radio frequency signal is a low-power signal, selecting a first target modulated radio frequency signal matching the first radio frequency signal from a plurality of modulated radio frequency signals; the plurality of modulated radio frequency signals being a plurality of radio frequency signals with different phases; and transmitting the first target modulated radio frequency signal for a first preset duration so that the master device exits the low-power mode.

[0008] According to a second aspect of one or more embodiments of this specification, a near-field communication module is provided for use in a slave device of near-field communication. The module may include: a signal detection triggering unit, a control unit, and an active modulation unit. The signal detection triggering unit is connected to the near-field antenna of the slave device and is used to acquire a first radio frequency signal emitted by a master device of near-field communication. If the first radio frequency signal is a low-power signal, a trigger signal is generated. The control unit is connected to the signal detection triggering unit and is used to acquire the trigger signal. The control unit is also connected to the active modulation unit and is used to control the active modulation unit to select a first target modulated radio frequency signal that matches the first radio frequency signal from a plurality of modulated radio frequency signals based on the trigger signal. The active modulation unit is connected to the near-field antenna. The near-field antenna is used to transmit the first target modulated radio frequency signal for a first preset duration so that the master device exits the low-power mode.

[0009] According to a third aspect of one or more embodiments of this specification, a near-field communication apparatus is provided, comprising: a signal acquisition module for acquiring a first radio frequency (RF) signal emitted by a near-field communication master device; a judgment module for determining whether the first RF signal is a low-power signal; wherein the low-power signal is an RF signal emitted by the master device in a low-power mode; a signal matching module for selecting a first target modulated RF signal that matches the first RF signal from a plurality of modulated RF signals if the first RF signal is a low-power signal; wherein the plurality of modulated RF signals are a plurality of RF signals with different phases; and a signal transmission module for transmitting the first target modulated RF signal for a first preset duration so that the master device exits the low-power mode. According to a fourth aspect of one or more embodiments of this specification, a near-field communication device is provided, the device being used to perform the above-described method, or the device comprising a module.

[0010] According to a fifth aspect of one or more embodiments of this specification, a computing device is provided, including a memory and a processor; the memory is used to store computer programs / instructions, and the processor is used to execute the computer programs / instructions, which, when executed by the processor, implement the steps of the above-described method.

[0011] According to a sixth aspect of one or more embodiments of this specification, a computer-readable storage medium is provided that stores computer instructions which, when executed by a processor, implement the steps of the method described above.

[0012] According to a seventh aspect of the embodiments of this specification, a computer program product is provided, including a computer program / instructions that, when executed by a processor, implement the steps of the above-described method.

[0013] One embodiment of this specification can achieve at least the following beneficial effects: After receiving the low-power radio frequency signal emitted by the master device, the slave device of near-field communication can select a target modulated radio frequency signal that matches the low-power radio frequency signal from a plurality of pre-set modulated radio frequency signals and transmit it. Thus, the master device can receive the target modulated radio frequency signal emitted by the slave device at the same time as it emits the low-power radio frequency signal. From the perspective of the master device, the radio frequency signal sensed by the master device is the superposition of its own low-power radio frequency signal and the target modulated radio frequency signal emitted by the slave device. This can change the amplitude of the radio frequency signal sensed by the master device, making the signal change on the master device larger, promoting the master device to exit the low-power mode and enter the normal card search mode, thereby improving the stability and success rate of near-field communication. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments or prior art of this specification, the drawings used in the description of the embodiments or prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this specification. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram illustrating an application scenario of a near-field communication method provided in one embodiment of this specification. Figure 2 This is a flowchart illustrating a near-field communication method provided in one embodiment of this specification; Figure 3 This is a flowchart illustrating a near-field communication method provided in one embodiment of this specification; Figure 4 This is a schematic diagram of the structure of a near-field communication module provided in one embodiment of this specification; Figure 5 This is a schematic diagram of the structure of a signal detection triggering unit provided in one embodiment of this specification; Figure 6 This is a schematic diagram of the structure of an active modulation unit provided in one embodiment of this specification; Figure 7 This is a schematic diagram of a near-field communication device provided in one embodiment of this specification; Figure 8 This is a structural block diagram of a computing device provided for one embodiment of this specification. Detailed Implementation

[0016] To enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this specification, and not all embodiments. Based on the embodiments in this specification, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this specification.

[0017] This specification uses specific terms to describe embodiments thereof. Terms such as "an embodiment," "one embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic associated with at least one embodiment of this specification. Therefore, it should be emphasized and noted that references to "an embodiment," "one embodiment," or "an alternative embodiment" in different locations throughout this specification do not necessarily refer to the same embodiment. Furthermore, those skilled in the art can combine and integrate the different embodiments or examples described herein, as well as the features of those different embodiments or examples, without contradiction.

[0018] The terminology used in one or more embodiments of this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the one or more embodiments of this specification. The singular forms “a,” “an,” “an,” “the,” and “the” as used in one or more embodiments of this specification and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used in one or more embodiments of this specification includes any or all possible combinations of one or more associated listed items.

[0019] The terms “comprising,” “including,” or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, product, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, product, or apparatus. Without further limitation, the presence of additional identical or equivalent elements in the process, method, product, or apparatus that includes said elements is not excluded.

[0020] Although the terms "first," "second," etc., may be used to describe various information in one or more embodiments of this specification, this information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, "first" may also be referred to as "second," and similarly, "second" may also be referred to as "first," without departing from the scope of one or more embodiments of this specification. Ordinal numbers such as "first," "second," etc., do not necessarily indicate order; often they are used to facilitate the distinction of objects. For example, "first server" and "second server" usually refer to two servers. To distinguish these two servers, they are described as "first server" and "second server." Of course, sometimes these two servers may be the same server.

[0021] The word “if” as used in one or more embodiments of this specification may be interpreted as “when”, “when”, or “in response to determination”, depending on the context.

[0022] In this specification, unless explicitly stated otherwise, "receiving and sending data" does not necessarily mean direct receiving and sending; it can also mean indirect receiving and sending. For example, A receiving data sent by B can be understood as A directly receiving the data sent by B, or it can be understood as A indirectly receiving the data sent by B through other entities such as C. Similarly, B sending data to A can be understood as B sending the data directly to A, or it can be understood as B indirectly sending the data to A through other entities such as C. Here, C can be one entity, or it can be two or more entities.

[0023] In this specification, unless explicitly stated otherwise, the relationships between structures can be direct or indirect. For example, when describing "A is connected to B," unless it is explicitly stated that A and B are directly connected, it should be understood that A can be directly connected to B or indirectly connected to B. Similarly, when describing "A is on top of B," unless it is explicitly stated that A is directly above B (AB is adjacent and A is above B), it should be understood that A can be directly above B or indirectly above B (AB is separated by other elements, and A is above B). And so on.

[0024] 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 one or more embodiments of this specification are all information and data authorized by the user or fully authorized by all parties. The collection, use and processing of related data shall comply with the relevant laws, regulations and standards of the relevant regions, and corresponding operation entry points shall be provided for users to choose to authorize or refuse.

[0025] The following explains the terms and concepts used in one or more embodiments of this specification.

[0026] NFC (Near Field Communication) is a short-range wireless communication technology operating at a frequency of 13.56 MHz, with a communication distance typically within 10 centimeters. This technology supports fast, secure, two-way communication between devices and is widely used in mobile payments, access control, public transport cards, and smart identification scenarios. In NFC communication, the device that actively transmits a card-finding signal can be called the master device or the transmitting device, such as an NFC card reader or a device in card reader mode. The device that passively responds to the signal transmitted by the master device can be called the slave device or the target device, such as an NFC tag, a device in card emulation mode, or a device with an NFC tag.

[0027] LPCD (Low-Power Card Detection): An energy-saving mechanism used by NFC controllers. It detects the presence of cards or card emulators nearby by periodically emitting radio frequency signals. Upon detecting a card or card emulator, the NFC controller is activated and enters normal operating mode.

[0028] Polling: The process by which the NFC controller actively searches its surroundings for other NFC devices, cards, or tags. By sending specific query signals, the NFC controller can detect available targets and initiate communication.

[0029] NFC, as a short-range wireless communication technology, boasts high security and fast connection advantages, and has been widely used in various smart devices. With technological advancements and growing market demand, most mainstream smartphones now integrate NFC functionality. LPCD mode is a power-saving mechanism in NFC controllers used to reduce power consumption. It detects the proximity of cards or card-simulated devices by periodically emitting radio frequency signals. When LPCD is enabled, the NFC controller only performs polling operations after detecting a proximity event, significantly reducing overall power consumption and improving device battery life and user experience.

[0030] Under ideal conditions, when a smartphone with LPCD (Low Power Card Detection) mode enabled approaches an external device, the change in coil coupling between the two devices triggers the NFC controller's wake-up mechanism, causing it to exit low power mode and send a polling signal to establish communication. However, in practical applications, due to differences in the NFC controller chip models, LPCD wake-up mechanisms, and antenna designs used by different mobile phone manufacturers, some devices may fail to detect the approach of an external device in a timely or reliable manner and exit LPCD mode, resulting in communication failure and impacting the success rate of interactions and user experience.

[0031] In related technologies, although external devices can actively transmit radio frequency fields to wake up some smartphones in LPCD mode and send polling signals, this radio frequency field may cause some devices to directly enter card emulation mode. If the external device itself is in card emulation mode, and the main device such as a smartphone also mistakenly enters card emulation mode, the mode conflict between the two will lead to communication failure.

[0032] To address the deficiencies in related technologies, in at least one embodiment of this specification, the slave device of near-field communication can select and transmit a modulation signal that matches the radio frequency signal emitted by the master device, such as a smartphone, thereby facilitating the master device to exit the low-power LPCD mode and enter the normal card search mode. It can also prevent the master device from mistakenly entering the card emulation mode, thereby improving the stability and success rate of near-field communication.

[0033] The technical solutions provided in the various embodiments of this specification are described in detail below with reference to the accompanying drawings.

[0034] Figure 1 This is a schematic diagram illustrating an application scenario of a near-field communication method provided in one embodiment of this specification. For example... Figure 1 As shown, the master device 100 of near-field communication (NFC) acts as a NFC reader device and can emit radio frequency (RF) signals to detect the presence of slave devices. In practical applications, to reduce power consumption, the master device 100 can first emit low-power RF signals in LPCD mode to detect the presence of nearby NFC slave devices, such as NFC cards. After sensing the RF signal emitted by the master device 100, the near-field antenna of the slave device 200 can generate electromagnetic coupling with the near-field antenna in the master device 100. This causes a change in the signal parameters in the master device 100. If the change in parameters in the master device 100 exceeds a threshold, the master device 100 can determine that the slave device 200 is nearby and can exit LPCD mode to conduct short-range communication with the detected slave device 200 through normal polling.

[0035] In one embodiment of this specification, to facilitate the master device 100's exit from LPCD mode as quickly as possible, the slave device 200 selects a modulated radio frequency signal from multiple modulated radio frequency signals of different phases that matches the low-power signal currently received by the master device 100 and transmits it. In this way, the master device 100 can sense the modulated radio frequency signal transmitted by the slave device while transmitting the low-power radio frequency signal. Under the influence of the modulated radio frequency signal, the signal parameters at the master device 100 will change more significantly; for example, the signal amplitude at the master device 100 may increase or decrease, thereby facilitating the master device 100's exit from low-power mode and entry into normal card-finding polling mode.

[0036] The main device 100 can be a device with near-field communication (NFC) card reader functionality, such as a smartphone, smartwatch, wristband, laptop, tablet, or other portable terminal device; it can also be a smart home device, in-vehicle device, or a POS machine, self-service checkout device, or other payment device. The slave device 200 can be a device with an NFC tag or a device that can simulate an NFC tag. For example, the slave device 200 can be a device used for processing payment transactions, such as a payment device used at a cashier or self-service checkout; or it can be a device for handling check-in, login, access control, turnstiles, etc., such as a device for checking in at work, school, or events using NFC; a device for member login or application login using NFC; an access control device for residential or office buildings; a card reader for public transportation such as buses and subways; or a device for identity or ticket verification at tourist attractions, events, or concerts. The specific types of the main and slave devices are not limited here.

[0037] This application provides a method for near-field communication, and also relates to a near-field communication module, a near-field communication device, a computing device, a computer-readable storage medium, and a computer program product, which will be described in detail in the following embodiments.

[0038] Figure 2 This is a flowchart illustrating a near-field communication method provided in one embodiment of this specification.

[0039] From a programming perspective, the execution entity of the process can be a program embedded in a slave device of near-field communication. It can be understood that this method can be executed by any device, equipment, platform, or cluster of devices with computing and processing capabilities.

[0040] like Figure 2 As shown, the process may include the following steps: Step 202: Acquire the first radio frequency signal emitted by the master device of near-field communication.

[0041] In practical applications, the NFC master device, acting as a NFC reader, can actively emit radio frequency (RF) signals to detect the presence of NFC cards nearby. If the master device has an LPCD (Limited-Time Discrete Calibration) working mode, the RF signal emitted by the master device can be an LPCD mode signal. Alternatively, the RF signal emitted by the master device can also be a normal polling signal.

[0042] The first radio frequency (RF) signal is an RF signal actively emitted by the master device. It can be a normal polling signal or a low-power signal emitted in LPCD mode. RF signals can represent electromagnetic waves with frequencies ranging from 3kHz to 300GHz. In the Near Field Communication (NFC) scenario, RF signals can represent electromagnetic waves with a 13.56MHz carrier wave and its modulation scheme.

[0043] NFC slave devices (such as card emulators) can be passive or active, relying on the radio frequency field emitted by the master device to obtain power and communicate. Alternatively, NFC slave devices can also communicate with the master device through their own power supply. In practical applications, the slave device's antenna coil can sense the alternating magnetic field generated by the master device's antenna to obtain the radio frequency signal emitted by the master device.

[0044] Step 204: Determine whether the first radio frequency signal is a low-power signal; the low-power signal is the radio frequency signal emitted by the main device in low-power mode.

[0045] Low-power signals can represent intermittent, low-duty-cycle, low-power 13.56MHz carrier pulses emitted by the master device in LPCD (Low Power Card Detection) mode, used to detect the presence of cards nearby, rather than for full communication.

[0046] Low-power LPCD mode can represent a power-saving state that the master device enters to extend battery life. It can periodically emit short radio frequency pulses and does not perform a full polling process.

[0047] The device can include modules or circuits for detecting the type of radio frequency (RF) signal. For example, it can output a high level for low-power signals, thereby triggering the subsequent process of selecting and modulating the RF signal. In practical applications, the type of RF signal can be determined by factors such as pulse length and intensity.

[0048] Step 206: If the first radio frequency signal is a low-power signal, then select a first target modulated radio frequency signal that matches the first radio frequency signal from among multiple modulated radio frequency signals.

[0049] The plurality of modulated radio frequency signals are radio frequency signals with different phases.

[0050] The slave device may include circuitry capable of generating modulated radio frequency signals of different phases. After acquiring a low-power signal emitted by the master device, the slave device can select a target modulated radio frequency signal that matches the low-power signal emitted by the master device from multiple modulated radio frequency signals of different phases.

[0051] In practical applications, the target modulated radio frequency (RF) signal can be either in phase with the first RF signal emitted by the master device or out of phase with the first RF signal. If the target modulated RF signal is in phase with the first RF signal, its phase is the same as or close to the phase of the first RF signal, which can enhance the amplitude of the signal on the master device side. The amplitude of the electromagnetic signal sensed by the master device side will increase, meaning the degree of signal change will increase, which is beneficial for the master device to exit the low-power mode. If the target modulated RF signal is out of phase with the first RF signal, its phase is opposite to or not close to the phase of the first RF signal, which can weaken the amplitude of the signal on the master device side. The amplitude of the electromagnetic signal sensed by the master device side will decrease, thus the degree of signal change will also increase, which is also beneficial for the master device to exit the low-power mode.

[0052] In one implementation, the first target modulated radio frequency signal is a radio frequency signal among the plurality of modulated radio frequency signals whose phase difference with the first radio frequency signal is less than or equal to a first preset threshold; or, the first target modulated radio frequency signal is a radio frequency signal among the plurality of modulated radio frequency signals whose phase difference with the first radio frequency signal is greater than or equal to a second preset threshold.

[0053] The first preset threshold can be a pre-defined angle value used to determine whether the phases are sufficiently close. If the absolute value of the phase difference between a modulated RF signal and the RF signal emitted by the main device is less than or equal to this threshold, then the modulated RF signal can be identified as the target modulated RF signal. By introducing a phase tolerance threshold, the dependence on phase detection accuracy can be reduced, and the stability of the system in noisy environments can be improved.

[0054] The second preset threshold can be a relatively large angle, used to identify inverted or near-inverted signals. The second preset threshold can be greater than the first preset threshold. In capacitive load modulation or reflection coefficient modulation, when the injected signal is 180° out of phase with the carrier or there is a large phase difference, it may cause a large drop in the antenna terminal voltage, making it easier for the master device to detect the impedance change, which can promote the master device to exit the low-power mode.

[0055] In practical applications, if there are multiple radio frequency signals among the multiple modulated radio frequency signals whose phase difference with the first radio frequency signal is less than or equal to the first preset threshold, or if there are multiple radio frequency signals whose phase difference with the first radio frequency signal is greater than or equal to the second preset threshold, one can be randomly selected from the multiple signals, or the radio frequency signal whose phase difference is closest to the first preset threshold or whose phase difference is least close to the second preset threshold can be selected as the target modulated radio frequency signal.

[0056] In practical applications, the target modulated radio frequency (RF) signal can be selected from multiple modulated RF signals, with the closest or least close phase to the first target RF signal. As one implementation, the first target RF signal is the modulated RF signal among the multiple modulated RF signals that has the closest phase to the first RF signal; or, the first target RF signal is the modulated RF signal among the multiple modulated RF signals that has the least close phase to the first RF signal.

[0057] Among them, the modulated radio frequency signal with the closest phase can be represented as the modulated radio frequency signal with the smallest absolute value of phase difference from the first radio frequency signal among all modulated radio frequency signals. In practical applications, in-phase superposition can maximize energy injection efficiency, making the antenna current change most significant in active load modulation, thereby generating the strongest detectable response on the master device side. Achieving maximized load modulation with phase coherence ensures that the master device can detect the presence of the card with the highest signal-to-noise ratio, significantly improving the reliability of interaction.

[0058] The modulated radio frequency (RF) signal with the least phase can be represented by the RF signal with the largest absolute phase difference from the first RF signal among all modulated RF signals, for example, a phase difference of 180°. In some card readers based on amplitude keying (ASK) detection, phase inversion modulation can cause a sudden drop in carrier amplitude, which can also prompt the master device to exit low-power mode. In practical applications, different master devices may adopt different response strategies. For example, some master devices may adopt an amplitude increase strategy, exiting low-power mode when the change in signal amplitude exceeds a preset threshold. Conversely, some master devices may adopt an amplitude decrease strategy, exiting low-power mode when the change in signal amplitude exceeds a preset threshold. Different target modulated RF signals can be used for different master devices.

[0059] In one embodiment of this specification, the slave device may not need to determine the response strategy adopted by the master device and may arbitrarily select a modulated radio frequency signal that is in phase or out of phase with the radio frequency signal emitted by the master device as the target modulated radio frequency signal. Alternatively, the target modulated radio frequency signal selected by the slave device may be pre-defined based on the response strategies adopted by most master devices in the region or application scenario where the master device is located. For example, if the response strategy adopted by most master devices is to increase the amplitude to exit low-power mode, the target modulated radio frequency signal may be a radio frequency signal that is in phase or close to the phase of the radio frequency signal emitted by the master device. Alternatively, based on the actual scenario requirements, the master devices that need to be prompted to exit low-power mode through the interference of the slave device's active modulated signal may be pre-determined, and the target modulated radio frequency signal selected by the slave device may be set according to the response strategy adopted by the master device. For example, in a scenario where a slave device needs to prompt a master device using a certain type of operating system to exit low-power mode, if the master device of that type of operating system adopts a strategy of exiting low-power mode by increasing the amplitude, the slave device can be set as a slave device that outputs the target modulated RF signal in phase; if the master device of that type of operating system adopts a strategy of exiting low-power mode by decreasing the amplitude, the slave device can be set as a slave device that outputs the target modulated RF signal in reverse phase.

[0060] Step 208: Transmit the first target modulated radio frequency signal for a first preset duration so that the master device exits the low power mode.

[0061] After identifying the target modulated radio frequency signal, the slave device can transmit it outward through its device antenna. The device antenna transmitting the target modulated radio frequency signal and the device antenna receiving the radio frequency signal transmitted by the master device can be the same antenna or different antennas.

[0062] During the transmission of the first target modulated RF signal by the slave device, the master device can be transmitting a low-power first RF signal without waiting for the master device to transmit a single pulse of RF signal and then transmitting a modulated RF signal between the transmissions of different pulses of RF signal. Once the slave device determines that the master device is transmitting a low-power RF signal, it can select the target modulated RF signal to transmit. The slave device can transmit its first modulated RF signal immediately after receiving the first low-power first RF signal from the master device. The time from sensing the master device's first RF signal to transmitting the first target modulated RF signal can be less than the pulse duration of a single RF signal transmitted by the master device. Influencing the first RF signal during the master device's transmission process does not require waiting for the master device to transmit multiple cycles of RF signals before the slave device transmits a modulated signal to influence the master device, thus enabling the master device to exit low-power mode more quickly.

[0063] In practical applications, the master device (such as a mobile phone or POS machine) continuously transmits a low-power 13.56MHz carrier wave in LPCD mode, forming an alternating magnetic field. The slave device is originally in a passive state, relying solely on inductive power. However, in one embodiment of this specification, the slave device can have an active modulation circuit that can generate modulated radio frequency signals with different phases. The slave device can actively inject a radio frequency field into the near-field space, which is spatially superimposed on the original field of the master device. The superposition result will significantly change the load impedance, Q value, or resonance characteristics of the master device's antenna circuit, specifically manifested as abrupt changes in antenna current, voltage amplitude, or phase. When the control unit of the master device detects this abnormal disturbance (such as exceeding the noise threshold and lasting for a certain period of time), it can exit LPCD mode and switch to the normal card search mode that sends Polling commands.

[0064] The first preset duration can represent the pre-set modulation duration. In practical applications, the master device needs to detect a sufficiently strong and continuous load change before determining the presence of a card and exiting the low-power mode. The slave device transmits a first target modulation radio frequency signal of the first preset duration, enabling the master device control unit to stably sample and decide to exit LPCD mode.

[0065] For example, after detecting the LPCD signal, the slave device actively modulates the signal with a 90° phase signal for 10µs. During this period, the master device continuously samples the antenna current and detects a significant and stable impedance shift, indicating that a card is approaching. It then exits the LPCD and sends a Polling command.

[0066] While one or more embodiments of this specification provide method steps as described in the embodiments or flowcharts, it is understood that the order of steps listed in the embodiments or flowcharts is merely one possible execution order among many steps and does not represent the only execution order. The order of some steps can be adjusted according to actual needs, or some steps can be omitted. When the claims involve method steps, adjustments to the order of such steps, or parallel execution between steps, are also within the scope of protection of the claims. For example, in practical applications, steps 204 and 206 can be executed synchronously. After acquiring the radio frequency signal emitted by the master device, the steps of determining whether the radio frequency signal is a low-power signal and selecting a matching target modulated radio frequency signal from multiple modulated radio frequency signals can be executed synchronously. In this case, if the radio frequency signal is a low-power signal, the target modulated radio frequency signal can be transmitted.

[0067] Figure 2The method described above allows the slave device to determine the modulation signal that matches the master device's RF signal from multiple modulation RF signals with different phases after receiving the low-power RF signal sent by the master device, and then send it. This proactively intervenes in the master device's state transition, promotes the master device's exit from low-power mode, and improves the stability and success rate of near-field communication.

[0068] based on Figure 2 In addition to the method described herein, one or more embodiments also provide some improvements or specific implementations of the method, which are described below.

[0069] In one or more embodiments of this specification, the slave device may include circuitry or logic for selecting a matching target modulated radio frequency (RF) signal. As one implementation, the target RF signal acting on the master device can be selected by superimposing a first RF signal transmitted by the master device with multiple pre-set modulation signals of different phases in the slave device. Optionally, selecting the first target RF signal matching the first RF signal from the multiple modulation RF signals may include: superimposing the first RF signal with each of the modulation RF signals to obtain multiple superimposed signals; and determining the first target RF signal matching the first RF signal based on the envelope amplitude of each superimposed signal.

[0070] Superposition processing can be represented as vector addition of two signals of the same frequency in the analog or digital domain, which can be physically achieved through analog adder circuits (such as summing circuits composed of operational amplifiers).

[0071] Each superimposed signal can represent a superimposed signal obtained by superimposing the modulated radio frequency signal of each different phase with the radio frequency signal emitted by the master device. Assuming there are N modulated radio frequency signals of different phases (such as 0°, 45°, 90°, etc.), N superimposed outputs can be generated, with each modulated radio frequency signal corresponding to one superimposed signal.

[0072] Envelope amplitude can represent the low-frequency amplitude signal obtained after superimposed signals are envelope-detected (such as diode detection, synchronous detection, or Hilbert transform), and can reflect the instantaneous power or field strength of radio frequency signals.

[0073] In practical applications, the modulated RF signal corresponding to the path with the largest, smallest, or exceeding threshold envelope amplitude can be selected as the first target modulated RF signal. Phase matching is indirectly achieved by comparing the superimposed envelope amplitudes, avoiding the use of high-precision phase detection circuits (such as phase detectors, ADCs, and digital processing), significantly reducing hardware complexity and power consumption. Simultaneously, this method is robust to noise and can stably select a suitable modulation phase in actual non-ideal channels, thereby improving the effectiveness of active load modulation and the success rate of master device wake-up.

[0074] As one implementation, the above-mentioned determination of a first target modulated radio frequency signal matching the first radio frequency signal based on the envelope amplitude of each superimposed signal may include: determining a target superimposed signal with the largest envelope amplitude from the various superimposed signals; and determining the modulated radio frequency signal from which the target superimposed signal is obtained as the first target modulated radio frequency signal.

[0075] Among them, the largest envelope amplitude can be represented by the instantaneous or average envelope value of each superimposed signal measured by an envelope detector (such as diode peak detection, synchronous detection or digital envelope extraction, etc.), and the largest value is selected after comparison.

[0076] The first target modulated RF signal can be the RF signal with the largest envelope amplitude when superimposed with the acquired RF signal emitted by the master device. By using the largest envelope amplitude as the matching criterion, the complex phase measurement problem is transformed into a simple amplitude comparison problem, eliminating the need for high-precision phase detection circuits and significantly reducing hardware complexity, power consumption, and cost. Furthermore, this method can still operate stably in real-world environments with noise or signal distortion, ensuring that active load modulation always occurs under approximately in-phase conditions, thereby maximizing the disturbance intensity to the master device antenna and improving the success rate of LPCD mode exit.

[0077] In practical applications, other methods can also be used to determine the target modulated radio frequency signal that matches the first radio frequency signal. For example, the phase information of the first radio frequency signal can be extracted, and then the target modulated radio frequency signal can be selected from various modulated radio frequency signals based on the extracted phase information. Specifically, phase-locked loops (PLLs) or digital phase-locked loops (DPLLs) can be used to extract the phase information of the first radio frequency signal; alternatively, zero-crossing detection can be used to perform high-precision timing of the rising edge / zero-crossing point of the first radio frequency signal, and then compare it with a local clock reference to calculate the relative phase.

[0078] In practical applications, using signal superposition to determine the target modulated RF signal is suitable for low-cost, low-power slave devices with short response times. Using phase extraction to determine the target modulated RF signal is suitable for high-performance slave devices. Different methods can be set according to actual needs.

[0079] To improve the accuracy of selecting the modulated radio frequency signal, optionally, the method in one embodiment of this specification may further include: performing gain control processing on the first radio frequency signal to obtain a gain-controlled radio frequency signal with a signal strength that meets a preset range.

[0080] Correspondingly, the above-mentioned superposition of the first radio frequency signal with each of the modulated radio frequency signals may include: superposition of the gain control radio frequency signal with each of the modulated radio frequency signals.

[0081] In this context, gain control processing can refer to the amplitude adjustment of the input RF signal through automatic gain control (AGC) or programmable gain amplifier (PGA).

[0082] A signal strength within a preset range indicates that the signal power or voltage amplitude has been adjusted to the appropriate operating range for subsequent circuits (such as adders, mixers, and envelope detectors), avoiding clipping or excessively low signal-to-noise ratios. This can solve the robustness problem caused by large fluctuations in LPCD signal strength in real-world environments (due to distance, antenna differences, different main equipment models, etc.).

[0083] The gain-controlled RF signal can represent the amplitude-normalized first RF signal, which serves as the input for subsequent superposition. This ensures that each superposition channel operates at the same input level, allowing the envelope amplitude comparison results to more accurately reflect phase differences and improve the accuracy of phase matching judgment.

[0084] In practical applications, the distance between the master and slave devices may vary from a few millimeters to a few centimeters, the LPCD transmit power of different master devices may differ by more than 10dB, and the antenna size and Q value of the slave devices may also be different. If the original inductive signals are directly superimposed, the signal may be too strong, causing the adder or envelope detector to saturate, resulting in envelope distortion and inability to distinguish phase differences; or the signal may be too weak, causing the envelope to approach the noise floor, the amplitude comparison to fail, and thus misselecting the unmatched phase.

[0085] In one embodiment of this specification, by performing gain control on the first radio frequency signal before superposition, its amplitude is stabilized within a preset range, effectively avoiding signal overload or insufficient signal-to-noise ratio caused by differences in the transmit power of the main device or changes in coupling strength. This ensures that the subsequent phase matching judgment based on the envelope amplitude has high accuracy and high robustness, thereby further improving the effectiveness of active load modulation and the success rate of main device wake-up.

[0086] In practical applications, there may be situations where the master device does not exit low-power mode after the slave device sends a modulated radio frequency signal once. To expedite the exit of the master device from low-power mode, the slave device can send the modulated radio frequency signal again. As one implementation, after transmitting the first target modulated radio frequency signal for a first preset duration, the process may further include: Determine whether the main device has exited low-power mode; If the low-power mode is not exited, the second radio frequency signal emitted by the master device is acquired; the second radio frequency signal is the radio frequency signal of another pulse emitted by the master device after the first radio frequency signal is emitted. Based on the second radio frequency signal, a second target modulated radio frequency signal that matches the second radio frequency signal is selected from the plurality of modulated radio frequency signals; Transmit the second target modulated radio frequency signal for a second preset duration to facilitate the master device exiting the low-power mode.

[0087] In practical applications, it can be determined whether the master device has exited low-power mode by monitoring whether it transitions from periodic LPCD pulses to continuous ISO / IEC 14443 Type A / B Polling frames (such as REQA or WUPA commands). Alternatively, circuits such as RF power meters can be used to detect the RF signals emitted by the master device to determine whether it has exited low-power mode.

[0088] The second radio frequency signal can represent the next radio frequency pulse signal emitted by the master device after sending the first radio frequency signal, which can also be called the first LPCD pulse.

[0089] The second target modulated radio frequency signal can be the modulated radio frequency signal to be transmitted selected from multiple modulated radio frequency signals according to the processing logic for selecting the first target modulated radio frequency signal described above. The second target modulated radio frequency signal can be the same as or different from the first target modulated radio frequency signal.

[0090] In practical applications, slight changes in the relative positions of the master and slave devices, antenna impedance drift, or errors in the initial phase detection can cause changes in the phase of the second radio frequency signal. In one embodiment of this specification, matching can be re-performed based on the newly acquired second radio frequency signal, rather than using the previous selection. This can improve the accuracy of selecting the modulation signal and facilitate the master device's exit from low-power mode.

[0091] The second preset duration can represent the transmission duration of the second target modulated radio frequency signal.

[0092] As one implementation, the second preset duration can be greater than the first preset duration to provide a stronger or more persistent disturbance.

[0093] In practical applications, if the previous or first short modulation may not be enough to trigger the master device's judgment, extending the modulation time can increase the probability of being sampled, thereby increasing the probability of the master device exiting the low-power mode.

[0094] Optionally, in order to reduce the impact on normal communication and to avoid the main device accidentally switching to card emulation mode or the card packet pop-up problem, the first preset duration and / or the second preset duration may be less than the signal pulse duration of the low power signal.

[0095] The signal pulse duration of a low-power signal (LPCD) represents the effective duration of the LPCD signal and is a part of the pulse period. For example, assuming the period of a master device's LPCD signal is 500ms and the pulse duration is 1ms, the first preset duration could be 0.2ms, and the second preset duration could be 0.3ms. Different master devices may transmit LPCD signals with different pulse durations. The pulse duration can be determined empirically, or it can be based on analysis of various master devices, selecting the average, maximum, minimum, or median pulse durations from each device as the basis for setting the first or second preset duration. Alternatively, the specific values ​​of the first or second preset duration can be determined by the success rate of near-field communication.

[0096] By setting the active modulation duration within the LPCD pulse duration, it is possible to ensure that the modulation energy acts on the effective detection window of the master device, maximizing the wake-up efficiency; at the same time, it avoids invalid transmission in the fieldless region, which can reduce the power consumption of the slave device, and also prevent communication anomalies or protocol compatibility issues caused by timing misalignment, thereby improving the system's robustness and standardization compatibility.

[0097] In one embodiment of this specification, phase matching is re-performed based on a new radio frequency signal after the first or previous wake-up failure, achieving adaptive compensation for dynamic environments and initial errors. This significantly improves wake-up robustness in scenarios with weak coupling, movement, or noise interference. Furthermore, it avoids the power waste caused by blindly modulating for extended periods without the main device exiting low-power mode, thus balancing reliability and energy efficiency.

[0098] In practical applications, the second radio frequency (RF) signal may be a normal card search signal or a low-power signal. To further avoid affecting normal communication and to avoid power waste caused by blind modulation, as an implementation method, after acquiring the second RF signal emitted by the main device, it can be determined whether the second RF signal is a low-power signal. The above-mentioned selection of a second target modulated radio frequency (RF) signal matching the second RF signal from the plurality of modulated RF signals based on the second RF signal may include: if the second RF signal is a low-power signal, then selecting a second target modulated RF signal matching the second RF signal from the plurality of modulated RF signals.

[0099] If the first radio frequency signal emitted by the master device is a low-power signal, the slave device can emit a matching first target modulated radio frequency signal. Under the influence of the first target modulated radio frequency signal, the master device may exit the low-power LPCD mode, or it may not exit the low-power mode. If the radio frequency signal of the next pulse emitted by the master device after the first radio frequency signal (the second radio frequency signal) is also a low-power signal, the slave device can also emit a second target modulated radio frequency signal that matches this low-power signal, further prompting the master device to exit the low-power mode.

[0100] In one implementation, the slave device can select the second target modulated radio frequency (RF) signal according to the logic of selecting the first target RF signal. For example, the second RF signal can be superimposed with multiple modulated RF signals, and the RF signal corresponding to the lowest superimposed signal with the largest envelope amplitude can be selected as the second target RF signal. Alternatively, the phase information of the second RF signal can be extracted, and the second target RF signal can be selected from multiple modulated RF signals based on the phase information.

[0101] Optionally, the second target modulated radio frequency signal is a radio frequency signal among the plurality of modulated radio frequency signals whose phase difference with the second radio frequency signal is less than or equal to a third preset threshold; or, the second target modulated radio frequency signal is a radio frequency signal among the plurality of modulated radio frequency signals whose phase difference with the second radio frequency signal is greater than or equal to a fourth preset threshold.

[0102] Alternatively, the second target modulated radio frequency signal is the modulated radio frequency signal among the plurality of modulated radio frequency signals whose phase is closest to that of the second radio frequency signal; or, the second target modulated radio frequency signal is the modulated radio frequency signal among the plurality of modulated radio frequency signals whose phase is least close to that of the second radio frequency signal.

[0103] The third preset threshold can be the same as or different from the first preset threshold. The fourth preset threshold can be the same as or different from the second preset threshold. Similar to the logic of selecting the first target modulated radio frequency signal, the second target modulated radio frequency signal can be a modulated radio frequency signal with a phase close to the second radio frequency signal, or it can be a modulated radio frequency signal with an opposite or dissimilar phase. It can be set according to actual needs, which will not be elaborated here.

[0104] In practical applications, the slave device may not be able to predict the response strategy adopted by the master device. Different card reader master devices have different sensitivities to modulation phase, and a single phase strategy may not be compatible with all devices. As one implementation method, when the first target modulation radio frequency signal fails to cause the master device to exit low-power mode, the second target modulation radio frequency signal can be a modulation radio frequency signal other than the first target modulation radio frequency signal among multiple modulation radio frequency signals.

[0105] Alternatively, the first target modulated radio frequency (RF) signal can be a modulated signal with a phase close to that of the first RF signal, and the second target RF signal can be a modulated signal with a phase dissimilarity to the second RF signal. For example, if the first target RF signal is an RF signal among multiple modulated RF signals whose phase difference with the first RF signal is less than or equal to a first preset threshold, the second target RF signal can be an RF signal among multiple modulated RF signals whose phase difference with the second RF signal is greater than or equal to a fourth preset threshold. Alternatively, the first target RF signal can be a modulated RF signal among multiple modulated RF signals whose phase is closest to that of the first RF signal, and the second target RF signal can be a modulated RF signal among multiple modulated RF signals whose phase is least close to that of the second RF signal.

[0106] Alternatively, the first target modulated radio frequency (RF) signal can be a modulated signal whose phase is not close to that of the first RF signal, while the second target RF signal can be a modulated signal whose phase is close to that of the second RF signal. For example, if the first target RF signal is an RF signal among multiple modulated RF signals whose phase difference with the first RF signal is greater than or equal to a second preset threshold, the second target RF signal can be an RF signal among multiple modulated RF signals whose phase difference with the second RF signal is less than or equal to a third preset threshold. Alternatively, the first target RF signal can be a modulated RF signal among multiple modulated RF signals whose phase is least close to that of the first RF signal, while the second target RF signal can be a modulated RF signal among multiple modulated RF signals whose phase is closest to that of the second RF signal.

[0107] In one embodiment of this specification, after the first or previous wake-up failure, a different modulation strategy can be switched to. For example, if the first selection is an in-phase or near-in-phase modulation RF signal, and the second selection is an out-of-phase or near-out-of-phase modulation RF signal, this can adapt to various types of master devices and significantly improve cross-vendor and cross-platform compatibility and wake-up success rate.

[0108] To further ensure that the master device can exit the low-power mode as quickly as possible, if the master device still has not exited the low-power mode after two modulations, the slave device can also send an excitation field signal. Optionally, in one embodiment of this specification, after transmitting the second target modulated radio frequency signal for a second preset duration, the method may further include: determining whether the master device has exited the low-power mode; if the master device has not exited the low-power mode, then sending a radio frequency excitation signal for a third preset duration.

[0109] The radio frequency (RF) excitation signal can be an RF signal of any phase, and can be a 13.56MHz continuous wave or modulated signal actively radiated by the antenna and driven by the slave device's own power supply. It can be independent of whether the master device is currently transmitting LPCD pulses. When the master device is not transmitting low-power LPCD signals, the slave device can transmit RF excitation signals to radiate electromagnetic fields into space.

[0110] The third preset duration can be the same as the first preset duration or the second preset duration, or the third preset duration can be greater than or less than the second preset duration or the first preset duration, and can be set according to actual needs.

[0111] In one embodiment of this specification, if the active load modulation based on phase matching in the first two stages fails to bring the master device out of low-power mode, a detectable electromagnetic disturbance is established in the near-field space by actively transmitting a radio frequency excitation signal, thereby improving the wake-up success rate of the master device. Simultaneously, this excitation signal is briefly activated when necessary, balancing power consumption controllability and user experience reliability.

[0112] In one implementation, if the plurality of modulated radio frequency signals are sorted according to their phase values, the phase difference between adjacent modulated radio frequency signals is the same.

[0113] Multiple modulated radio frequency (RF) signals can be structured with uniform phase quantization or equally spaced phase grids, and the phase interval can be a fixed value. The phase interval can be 360° / N, where N is the total number of modulated RF signals. For example, with 4 modulated RF signals, the phases can be 0°, 90°, 180°, and 270°. Similarly, with 2 modulated RF signals, the phases can be 0° and 180°. Furthermore, with 8 modulated RF signals, the phases can be 0°, 45°, 90°, 135°, 180°, 225°, 270°, and 315°.

[0114] In one embodiment of this specification, by setting multiple modulated radio frequency signals to be distributed with equal phase intervals, the ability to match the phase of any input LPCD signal is ensured, and the phase matching error can be minimized. On the other hand, it simplifies the design complexity of the phase generation, selection and control circuits, improves the system symmetry and manufacturing yield, and provides a unified hardware foundation for multiple wake-up strategies such as in-phase / out-of-phase, thereby achieving a highly robust auxiliary card finding function with limited hardware resources.

[0115] Figure 3 This is a flowchart illustrating a near-field communication method provided in one embodiment of this specification. Figure 3As shown, after the slave device's system starts working, the parameters of the slave device's control unit can be initialized to prepare for subsequent control. Then, the control unit can set the circuit unit used for phase detection to the active path, waiting for the rising edge signal of the low-power LPCD detection trigger circuit used to detect whether the RF signal emitted by the master device is a low-power signal. When the first RF signal emitted by the master device is detected as a low-power LPCD pulse signal, the low-power LPCD detection trigger circuit generates a rising edge signal and triggers an external interrupt of the control unit. If this interrupt is entered for the first time, the phase detection and active load modulation circuits are used to perform phase detection and phase selection, selecting the first target modulated RF signal whose phase matches the first RF signal emitted by the master device, for example, the signal with the closest phase. After phase selection, the first target modulated RF signal can be emitted for a time T1 (e.g., 10µs). After that, the control unit can switch back to the phase detection path and then determine whether the master device sends a polling signal. If the master device sends a polling signal, it indicates that the master device has exited low-power mode, and the slave device can delay for Td1 time before re-initializing the system and ending active modulation. Otherwise, the slave device can wait for the next interrupt trigger. If the interrupt is triggered a second time, and the second RF signal emitted by the master device is still a low-power signal, the low-power LPCD detection trigger circuit will generate a rising edge signal to trigger the external interrupt of the control unit again. This is the second interrupt. Then, the phase detection and active load modulation circuit is used to perform phase detection and phase selection. A second target modulated RF signal that matches the phase of the second RF signal emitted by the master device is selected and sent for T2 (e.g., 40µs). After that, the control unit can switch back to the phase detection path. Then, it is determined whether the master device sends a polling signal. If it does, the system is reinitialized after a delay of Td1. Otherwise, after a delay of Td2, an RF field with arbitrary phase and a duration of T3 is emitted, and then the system is reinitialized after a delay of Td1. As one implementation, the delay Td1 satisfies the requirement of initializing the system after communication is completed. For example, if the total duration of NFC communication is 1 second, the delay time can be greater than this time. The delay Td2 can be a shorter time, such as about 10ms, and then the RF field is actively emitted directly.

[0116] In practical applications, if the first radio frequency signal sent by the master device obtained from the device is a polling signal, the relevant active modulation process can be omitted.

[0117] In practical applications, the durations of polling and LPCD signals differ significantly. For example, a polling signal can last for hundreds of milliseconds, while an LPCD signal lasts for tens of microseconds. If it's an LPCD signal, the high level will only last for tens of microseconds, while if it's a polling signal, the high level will last for hundreds of milliseconds. For instance, if the level is detected approximately 1 millisecond after an interrupt is triggered, and it's still high, it indicates that the master device is sending a normal card-finding polling signal. If no level is detected within 1 millisecond after the interrupt is triggered, or no high level is detected, it indicates that the master device is sending a low-power LPCD signal.

[0118] The various technical features in the above embodiments can be combined arbitrarily, as long as there is no conflict or contradiction between the combinations of features. However, due to space limitations, they have not been described one by one. Therefore, the arbitrary combination of various technical features in the above embodiments is also within the scope of this specification.

[0119] Based on the same idea, one embodiment of this specification also provides a module corresponding to the above method. Figure 4 This is a schematic diagram of a near-field communication module provided in one embodiment of this specification. This module can be used as a slave device in near-field communication and can execute the methods described in the above embodiments.

[0120] like Figure 4 As shown, the module 400 may include: a signal detection triggering unit 402, a control unit 404, and an active modulation unit 406.

[0121] The signal detection trigger unit 402 is connected to the near-field antenna 202 of the slave device 200 and is used to acquire the first radio frequency signal emitted by the master device 100 of near-field communication. If the first radio frequency signal is a low-power signal, a trigger signal is generated.

[0122] The control unit 404 is connected to the signal detection trigger unit 402 and is used to acquire the trigger signal.

[0123] The control unit 404 is also connected to the active modulation unit 406 and is used to control the active modulation unit 406 to select a first target modulation radio frequency signal that matches the first radio frequency signal from a plurality of modulation radio frequency signals based on the trigger signal.

[0124] The active modulation unit 406 is connected to the near-field antenna 202; the near-field antenna 202 is used to transmit the first target modulated radio frequency signal for a first preset duration so that the main device exits the low-power mode.

[0125] The master device 100 can also be an NFC card reader, and may include a card reader antenna 102 and a card reader control unit 104. The slave device 200 can also be called an NFC card emulation device or a card device, and may include a near-field antenna 202 and a communication control unit 204. A near-field communication module 400 provided in one embodiment of this specification can be applied to the slave device 100, for example, it can be included inside the slave device 100 as part of the slave device 100. The module 400 may include a signal detection trigger circuit 402, a control unit 404, and an active modulation unit 406. The master device and the slave device achieve near-field coupling through the antenna, and the remaining modules or units can achieve data transmission and control through electrical connections.

[0126] The signal detection trigger unit can be connected to the NFC near-field antenna of the slave device, enabling it to acquire the first radio frequency (RF) signal emitted by the master device and determine whether the RF signal emitted by the master device is a low-power signal. As one implementation, if the RF signal emitted by the master device is a low-power signal, the signal detection trigger unit can output a digital trigger signal (such as a rising edge interrupt) so that the control unit can trigger the selected modulation RF signal. The signal detection trigger unit may include a bandpass filter, an RF power meter, a comparator, a shaping circuit, etc.

[0127] The control unit can receive a trigger signal and control the active modulation unit. Specifically, in response to the trigger signal, it can activate the phase matching logic, select a first target modulation radio frequency signal from multiple pre-stored modulation radio frequency signals that matches the first radio frequency signal, and output a strobe signal or configuration parameters to the active modulation unit. The control unit can be a microcontroller (MCU), a state machine, or a dedicated logic circuit, etc.

[0128] The active modulation unit can be connected to the control unit and the near-field antenna. It can generate a modulation signal of the selected phase according to the control unit's instructions and inject this signal into the near field within a first preset duration, achieving active load modulation and changing the equivalent load of the main device antenna. The active modulation unit may include components such as a multi-phase oscillator, an RF switch, and a power amplifier.

[0129] In one embodiment of this specification, a near-field communication module integrating three functional units—signal detection, intelligent control, and active modulation—can automatically sense and actively apply phase-matching load disturbances when the master device is in a low-power detection state, thereby promoting the master device to exit the low-power mode and improving the master device's wake-up success rate.

[0130] In one embodiment of this specification, the signal detection triggering unit can generate a trigger signal within a short time. The signal detection triggering unit can generate a trigger signal within a preset duration based on the radio frequency signal emitted by the master device sensed from the device's near-field antenna. This preset duration can be less than the pulse duration of a low-power radio frequency signal emitted by the master device.

[0131] As one implementation method, Figure 5 This is a schematic diagram of the structure of a signal detection triggering unit provided in one embodiment of this specification, as shown below. Figure 5 As shown, the signal detection triggering unit may include a bandpass filter circuit 502, a buffer adjustment circuit 504, an RF power meter 506, and a comparison triggering circuit 508. The output terminal of the bandpass filter circuit 502 is connected to the input terminal of the buffer adjustment circuit 504; the output terminal of the buffer adjustment circuit 504 is connected to the input terminal of the RF power meter 506; and the output terminal of the RF power meter 506 is connected to the input terminal of the comparison triggering circuit 508. The signal detection triggering unit is connected to the near-field antenna of the slave device, which may include: the input terminal of the bandpass filter circuit 502 being connected to the near-field antenna 202 of the slave device. The control unit is connected to the signal detection triggering unit, which may include: the control unit 404 being connected to the output terminal of the comparison triggering circuit 508.

[0132] A bandpass filter circuit is a circuit that allows only signals within a preset frequency band to pass through, such as signals at 13.56MHz or 13.56MHz ± several hundred kHz. It can suppress environmental noise, harmonics, and interference from other frequency bands, preventing false triggering by non-NFC signals and improving detection specificity. Bandpass filter circuits can include components such as LC resonant circuits, ceramic filters, or active filters.

[0133] A buffer adjustment circuit can adjust LPCD signals of different intensities to the appropriate dynamic range of the RF power meter. It avoids drawing excessive current from the front-end (antenna), preventing impact on the antenna Q value and energy harvesting, and can also drive the subsequent RF power meter, ensuring signal integrity. The buffer adjustment circuit can include emitter followers, operational amplifier buffers, or programmable gain buffers, etc.

[0134] An RF power meter can linearly map the power (or squared amplitude) of an input RF signal to a DC voltage, outputting a slowly changing DC signal for easy comparison. RF power meters can be based on diode square-law detection, thermopile, or dedicated ICs.

[0135] The comparator trigger circuit compares the DC voltage output by the RF power meter with a preset threshold voltage. When the voltage exceeds the preset threshold, it outputs a digital rising edge signal, which is sent to the control unit as an external interrupt. The comparator trigger circuit may include a high-speed comparator, a Schmitt trigger shaper, etc.

[0136] The signal detection trigger unit can read and detect the LPCD signal from both ends of the near-field antenna, and the detection result can be output to the control unit in the form of a rising edge. The RF signals at the near-field antenna, such as the first RF signal and the second RF signal, after being input to the signal detection trigger unit, can first undergo a 13.56MHz bandpass filter to remove interference signals. The buffer adjustment circuit has high input impedance and low output impedance characteristics, and can also adjust the signal amplitude to the dynamic range adapted to the RF power meter, realizing signal buffer adjustment. The RF power meter can map the power of the input RF signal to a DC voltage. When the output voltage of the RF power meter exceeds the set threshold of the comparison trigger circuit, a rising edge signal is generated to trigger an external interrupt of the auxiliary card search control unit.

[0137] In practical applications, both the low-power LPCD signal and the normal card search polling signal may generate rising signals and trigger interrupts, but their durations are significantly different. The low-power LPCD signal lasts for tens of microseconds, while the normal card search polling signal lasts for hundreds of milliseconds. The signal detection triggering unit can also have algorithmic logic to distinguish between the low-power LPCD signal and the normal card search polling signal.

[0138] In one embodiment of this specification, a four-stage analog link consisting of bandpass filtering, buffer conditioning, power detection, and threshold comparison is employed. This signal detection triggering unit can identify LPCD pulses with high sensitivity and selectivity in strong interference environments and convert them into reliable digital trigger signals. At the same time, the buffer conditioning circuit ensures impedance matching between the preceding and following stages and adapts the signal dynamic range, preventing saturation due to excessively strong signals or being overwhelmed by noise due to excessively weak signals. This provides an accurate start-up opportunity for subsequent phase matching and active modulation, significantly improving system robustness and wake-up reliability.

[0139] In practical applications, the signal detection trigger unit can also be implemented in other ways. For example, it can be a unit based on phase-locked loop (PLL) or frequency / phase lock detection, which can include PLL circuits, phase / frequency error output circuits, and decision logic. If the master device transmits continuous or periodic carrier waves, the PLL can lock and output a lock status signal; the LPCD pulse can be regarded as a brief lock event. Another example is an incoherent method based on energy detection, which can include a broadband receiver, energy integrator, threshold comparison, etc., to detect whether there is burst energy within a preset frequency band (such as the 13.56MHz band), and can be implemented using a zero-IF receiver or a power detection IC.

[0140] Figure 6 This is a schematic diagram of an active modulation unit provided in one embodiment of this specification. Figure 6 As shown, the active modulation unit may include a modulation signal circuit 602, an adder circuit 604, an envelope extraction circuit 606, a phase detection circuit 608, and a phase selection circuit 610.

[0141] The output terminal of the modulation signal circuit 602 is connected to the input terminal of the adder circuit 604; the modulation signal circuit 602 is used to output the plurality of modulated radio frequency signals; the adder circuit 604 is used to superimpose the plurality of modulated radio frequency signals with the first radio frequency signal respectively.

[0142] The output terminal of the adder circuit 604 is connected to the input terminal of the envelope extraction circuit 606; the envelope extraction circuit 606 is used to extract the envelope amplitude of the superimposed signal obtained by superimposing the plurality of modulated radio frequency signals with the first radio frequency signal.

[0143] The electrical output terminal of the envelope extraction circuit 606 is connected to the input terminal of the phase detection circuit 608; the phase detection circuit 608 can determine the first target modulated radio frequency signal based on the envelope amplitude of the multiple superimposed signals.

[0144] The output terminal of the phase detection circuit 608 is connected to the input terminal of the control unit 404; the output terminal of the control unit 404 is connected to the input terminal of the phase selection circuit 610; the control unit is used to control the phase selection circuit to select and turn on the modulation circuit that can output the first target modulated radio frequency signal.

[0145] The active modulation unit described above is connected to the near-field antenna, which may include: the output terminal of the phase selection circuit 610 is connected to the near-field antenna 202 so that the near-field antenna 202 transmits the first target modulated radio frequency signal.

[0146] Modulation signal circuits can be used to generate multiple modulation signals with different phases, such as 13.56MHz modulation signals with different phases. A modulation signal circuit can include a signal source with a preset frequency and different phase units, such as a numerically controlled oscillator (NCO), a voltage-controlled oscillator (VCO), or a phase shifter network.

[0147] An adder circuit can contain multiple independent adders (or summing nodes), each of which superimposes a modulated signal with the acquired RF signal from the master device, such as a first RF signal and a second video signal. The adder circuit may include a resistor summing network, an operational amplifier adder, or an RF hybrid coupler, etc.

[0148] Envelope extraction circuits can perform envelope detection on each superimposed signal and output its instantaneous or average amplitude. Envelope extraction circuits may include diode peak detectors, synchronous detectors, or RMS-to-DC converters, etc.

[0149] Phase detection circuits can be used to compare multiple envelope amplitudes to identify the desired modulation path, such as finding the channel index corresponding to the maximum value. Phase detection circuits may include multiplexers, encoders, etc.

[0150] The phase selection circuit can, according to the control unit's instructions, direct the modulation signal path of the corresponding channel to the antenna. The phase selection circuit may include RF analog switches, transmission gate arrays, or multiplexers, etc.

[0151] In practical applications, active modulation units can generate multiple sets of modulation signals with different phases, such as... Figure 6 There are four types. Assume the low-power signal emitted by the master device is... ,in, It is the signal amplitude. It is the signal frequency. Represents phase.

[0152] Phase is The modulated radio frequency signal is defined as .in, This indicates the phase of the modulated signal. The adder circuit will... and The superimposed signal can be obtained by adding them together. for .

[0153] According to the sum-to-product formula, the above equation can be simplified to: .

[0154] in envelope amplitude It can be represented as .

[0155] As one implementation method, when the LPCD low-power signal and the phase are When the phases of the modulated signals are closest, their envelope amplitudes The maximum value is determined by the envelope size. Therefore, after envelope extraction, the phase proximity of the superimposed signals can be inferred by judging the envelope size. The phase detection circuit can detect the envelope size of the superimposed four signals and output a reference signal with the largest envelope through high and low level signals. The control unit can then adjust the phase selection circuit to select the selected signal based on the detection result and transmit the selected target modulated radio frequency signal through the near-field antenna.

[0156] The target modulated RF signal and the LPCD low-power signal have close phase, at which point the signal amplitude at both ends of the main device antenna is reduced from... Change to This process has the same effect as a change in the equivalent impedance of the host device's antenna. When the host device's control unit detects this change, it will either further confirm the change or exit low-power mode and send a polling signal, depending on its low-power response strategy.

[0157] Understandable Figure 6 This is merely an illustration of an active modulation unit. In practical applications, active modulation units can also be implemented in other ways. For example, they can be implemented using phase-locked loops (PLLs) or delay-locked loops (DLLs) for phase tracking. The LPCD signal input is quickly captured by the PLL, and after the PLL locks, its VCO output is an in-phase signal. Alternatively, multiple phase delay versions can be generated using multi-tap delay lines (DLLs), and the tap aligned with the input signal is selected as the modulation signal. Another approach is to use a single-channel adjustable phase shifter combined with feedback optimization. Specifically, a fixed reference signal (e.g., a 0° modulation signal) can be generated first, and the phase can be adjusted using a voltage- or digitally controlled variable phase shifter. The modulation signal is then transmitted, and the response of the master equipment is monitored (e.g., through antenna voltage feedback). A hill-climbing algorithm or gradient search is used to automatically adjust the phase shift to maximize the disturbance. Yet another approach is to use a coarse detection combined with fine adjustment. First, an envelope comparison method is used to quickly select candidate phases (e.g., 2 or 3). From the candidate set, digital fine-tuning or feedback optimization is used to further select a matching modulation signal.

[0158] To improve communication stability and provide more accurate modulated radio frequency signals, one implementation method is as follows: Figure 6 As shown, the active modulation unit further includes an RF switch 612. The input terminal of the RF switch 612 can be connected to the near-field antenna 202 to acquire the first RF signal; the output terminal of the RF switch 612 and the output terminal of the modulation signal circuit 602 are respectively connected to the input terminal of the adder circuit 604.

[0159] The radio frequency switch may have at least two ports: an input port for connecting to a near-field communication antenna to receive a first radio frequency signal emitted by the main device; and an output port for connecting to one input port of the adder circuit. The output port of the modulation signal circuit is also connected to the other input port of the adder circuit. The adder circuit can have two input signals: one is the original LPCD signal from the antenna, and the other is a locally generated modulated RF signal. When the RF switch is turned on, the adder circuit can acquire the RF signal sensed by the near-field antenna.

[0160] RF switches can be used to isolate the antenna from the analog front end and prevent load effects. If the LPCD signal is directly coupled from the antenna to the adder circuit, the input impedance of the adder circuit will be applied to the antenna resonant circuit, reducing the Q value and affecting energy harvesting efficiency and communication sensitivity. With an RF switch, the signal can be turned on only when detection is needed and turned off at other times, reducing the impact on the antenna.

[0161] Radio frequency (RF) switches can also be used to control the timing of signal paths. LPCD signals are intermittent pulses (e.g., once every 500ms, lasting 1ms); the RF switch can be turned on by the control unit within the detection window and turned off at other times to avoid noise injection or DC offset accumulation, thereby improving the signal-to-noise ratio (SNR) and system stability.

[0162] To further improve the accuracy of selecting the modulated radio frequency signal and better facilitate the main device's exit from low-power mode. For example... Figure 6 As shown, in one embodiment, the active modulation unit further includes a gain control circuit 614; the gain control circuit is used to perform gain control processing on the first radio frequency signal to obtain a gain control radio frequency signal with a signal strength that meets a preset range.

[0163] Wherein, the output terminal of the RF switch and the output terminal of the modulation signal circuit are respectively connected to the input terminal of the adder circuit, which may include: the output terminal of the RF switch being connected to the input terminal of the gain control circuit; and the output terminal of the gain control circuit and the output terminal of the modulation signal circuit being respectively connected to the input terminal of the adder circuit.

[0164] The gain control circuit can be an automatic gain control (AGC) loop, which may include a variable gain amplifier (VGA), envelope detector, feedback comparator, etc., capable of adjusting the gain in real time to stabilize the output envelope at the target value. Alternatively, the gain control circuit can be a programmable gain amplifier (PGA), which allows the control unit to set a fixed gain level based on a coarse power estimate, resulting in lower power consumption. Another option is a digitally assisted automatic gain control (AGC), which digitally calculates the gain after sampling and then configures the analog programmable gain amplifier (PGA). No specific limitations are imposed here.

[0165] In practical applications, a low-power signal (such as the first radio frequency signal) is input to the active modulation unit via a radio frequency switch, and a gain control signal can be obtained through automatic gain control. ,in, It is the signal amplitude after automatic gain control. It is the signal frequency. The phase can be a random phase relative to the local signal source.

[0166] In one embodiment of this specification, by cascading a gain control circuit after the RF switch, the LPCD signal with a wide dynamic range is automatically adjusted to a preset amplitude range suitable for superposition and envelope detection, effectively avoiding circuit saturation or insufficient signal-to-noise ratio caused by differences in the transmit power of the main device or changes in coupling strength; thereby ensuring that the comparison result of the envelope amplitude can be determined by the phase difference, significantly improving the phase matching accuracy and wake-up reliability, while being compatible with various main devices and usage scenarios.

[0167] To more effectively facilitate the main device's exit from low-power mode, optional features include... Figure 6 As shown, the active modulation unit may further include a power amplifier circuit 616; the power amplifier circuit is used to amplify the original radio frequency signal output by the modulation circuit selected by the phase selection circuit to obtain the first target modulated radio frequency signal.

[0168] The output terminal of the aforementioned phase selection circuit is connected to the near-field antenna, which may include: the output terminal of the phase selection circuit being connected to the input terminal of the power amplifier circuit; and the output terminal of the power amplifier circuit being connected to the near-field antenna.

[0169] In practical applications, the output power of the phase selection circuit may be limited. For example, the phase selection circuit can be composed of an analog switch or a transmission gate, which has a high output impedance and weak driving capability. If it directly drives the antenna, the signal amplitude will be small and unable to generate effective near-field disturbance. In one embodiment of this specification, the power amplifier circuit can be an RF power amplifier, which can balance efficiency and linearity. For example, in near-field communication scenarios, the center frequency of the power amplifier circuit can be 13.56 MHz, and the bandwidth can cover the NFC modulation sideband. It can be controlled by the control unit to be turned on during the transmission of modulated RF signals, such as during the first preset duration, the second preset duration, and the third preset duration, to save power consumption.

[0170] In one embodiment of this specification, a power amplifier circuit is introduced to amplify the phase-selected modulation signal to a power level sufficient to effectively disturb the near field of the master device, thereby enhancing the strength and reliability of active load modulation. Furthermore, the power amplifier can be activated when necessary, balancing wake-up performance with slave device power consumption control. For small terminals with limited antenna efficiency, it can also successfully trigger the master device to exit low-power mode in weakly coupled scenarios.

[0171] Optionally, after selecting the phase circuit to be turned on, the debugging RF signal of this path can be output to the RF switch through the power amplifier. The common port of the RF switch is connected to the port where the power amplifier output is located. This signal is transmitted through the near-field antenna and coupled to the antenna of the main device through the near field.

[0172] In practical applications, the active modulation unit may also include a bandpass filter circuit, or the bandpass filter circuit in the signal detection trigger unit and the active modulation unit may be the same bandpass filter circuit, used to remove interference signals.

[0173] Based on the near-field communication methods described in the above embodiments, the working process of the near-field communication module provided in one or more embodiments of this specification will be described here. In practical applications, after the radio frequency (RF) signal emitted by the main device is obtained from the near-field antenna of the device, the RF signal can be input to the signal detection trigger unit for filtering, buffering, power measurement, and comparison triggering. If the RF signal is a low-power signal, a trigger signal, such as an interrupt signal, can be generated and input to the control unit. At the same time, the control unit can initialize the RF switch connected to the gain control circuit. In this way, the RF signal emitted by the main device can also be superimposed with multiple phase modulation signals simultaneously. The envelope amplitude of each path is obtained through the envelope extraction circuit, and then the phase detection circuit obtains the path with the largest or smallest envelope amplitude and transmits it to the control unit. The process of superimposing multiple modulated RF signals with the RF signal emitted by the main device and then selecting the matching modulated RF signal can be performed synchronously after obtaining the RF signal emitted by the main device and the process of determining whether the RF signal is a low-power signal, or it can be performed after determining that the RF signal is a low-power signal.

[0174] After the control unit is triggered by an external interrupt, it selects the corresponding signal through the phase selection circuit based on the acquired matching phase information. The RF switch is then switched and held to the corresponding channel of the power amplifier for active load modulation, with the holding time being, as described above, the first preset duration, the second preset duration, etc. After active load modulation is completed, it can switch back to the automatic gain control channel. If the main device still has not exited low-power mode after the terminal sends a second preset duration of debugging RF signal, as one implementation method, the phase selection circuit can select 0 degrees, or other degrees. Then, the RF switch switches and holds one channel of the power amplifier for a third preset duration, and then returns to the automatic gain control channel, waiting for the next active modulation.

[0175] This specification provides a method or module for rapidly converting the power of a low-power signal into a DC signal using an RF power meter, and generating a rising edge signal to be output to a control unit via a comparison trigger circuit. The trigger response time can be less than 1µs, enabling faster active modulation of the master device.

[0176] In one embodiment of this specification, a method is provided to detect the phase difference between a low-power signal and a radio frequency signal with different phase modulations by superimposing signals, and to select the modulation signal with the closest or dissimilar phase for active load modulation, which can quickly change the equivalent impedance of the main device antenna, enabling the main device to exit the low-power mode more quickly.

[0177] In one embodiment of this specification, a master device in LPCD mode can be quickly woken up and prompted to send a polling signal by two unequal-timing phase-coherent active load modulations and one active field transmission. This solves the randomness and instability caused by phase incoherence in existing active load modulations and effectively prevents the master device from entering card emulation mode after receiving an external radio frequency field, thereby improving the success rate and stability of NFC interactions and enhancing the user experience. Based on the same idea, an embodiment of this specification also provides a corresponding device for the above method.

[0178] Figure 7 This is a schematic diagram of a near-field communication device provided in one embodiment of this specification. Figure 7 As shown, the device may include: The signal acquisition module 702 is used to acquire the first radio frequency signal emitted by the master device of near-field communication; The judgment module 704 is used to determine whether the first radio frequency signal is a low power signal; the low power signal is the radio frequency signal emitted by the main device in low power mode; The signal matching module 706 is used to select a first target modulated radio frequency signal that matches the first radio frequency signal from a plurality of modulated radio frequency signals if the first radio frequency signal is a low-power signal; the plurality of modulated radio frequency signals are a plurality of radio frequency signals with different phases. The signal transmitting module 708 is used to transmit the first target modulated radio frequency signal for a first preset duration so that the master device exits the low power mode.

[0179] It is understood that the modules mentioned above refer to computer programs or program segments used to perform one or more specific functions. Furthermore, the distinction between these modules does not imply that the actual program code must also be separate.

[0180] For ease of description, the above devices are described by dividing them into various modules or units based on their functions. Of course, when implementing one or more of these specifications, the functions of each module or unit can be implemented in the same or different software and / or hardware, or a module that performs the same function can be implemented by a combination of multiple sub-modules or sub-units, etc. The device embodiments described above are merely illustrative. For example, the division of units is only a logical functional division; in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed.

[0181] The above is a schematic representation of a near-field communication device according to this embodiment. It should be noted that the technical solution of this near-field communication device and the technical solution of the aforementioned near-field communication method belong to the same concept. Details not described in detail in the technical solution of the near-field communication device can be found in the description of the technical solution of the aforementioned near-field communication method. This device can be a slave device in near-field communication, or it can be a component of a slave device, or it can be associated with a slave device.

[0182] Based on the same idea, one embodiment of this specification also provides a near-field communication device, which is used to perform the above-described near-field communication method, or the device may include the above-described near-field communication module.

[0183] Based on the same idea, this specification also provides devices corresponding to the above methods in its embodiments.

[0184] Figure 8 A structural block diagram of a computing device 800 provided according to an embodiment of this specification is shown.

[0185] The computing device 800 includes: Memory 810 and processor 820; The memory 810 is used to store computer programs / instructions, and the processor 820 is used to execute the computer programs / instructions, which, when executed by the processor 820, implement the steps of the above-described near-field communication method.

[0186] Specifically, the components of the computing device 800 include, but are not limited to, a memory 810 and a processor 820. The processor 820 is connected to the memory 810 via a bus 830, and the database 850 is used to store data.

[0187] The computing device 800 also includes an access device 840, which enables the computing device 800 to communicate via one or more networks 860. Examples of these networks include Public Switched Telephone Network (PSTN), Local Area Network (LAN), Wide Area Network (WAN), Personal Area Network (PAN), or combinations of communication networks such as the Internet. The access device 840 may include one or more of any type of wired or wireless network interface (e.g., a network interface card (NIC)), such as an IEEE 802.11 Wireless Local Area Network (WLAN) wireless interface, a Wi-MAX (Worldwide Interoperability for Microwave Access) interface, an Ethernet interface, a Universal Serial Bus (USB) interface, a cellular network interface, a Bluetooth interface, a Near Field Communication (NFC) interface, and so on.

[0188] In one embodiment of this specification, the above-described components of the computing device 800 and Figure 8 Other components, not shown, can also be connected to each other, for example, via a bus. It should be understood that... Figure 8 The block diagram of the computing device shown is for illustrative purposes only and is not intended to limit the scope of this application. Those skilled in the art can add or replace other components as needed.

[0189] The computing device 800 can be any type of stationary or mobile computing device, including mobile computers or mobile computing devices (e.g., tablet computers, personal digital assistants, laptop computers, notebook computers, netbooks, etc.), mobile phones (e.g., smartphones), wearable computing devices (e.g., smartwatches, smart glasses, etc.) or other types of mobile devices, or stationary computing devices such as desktop computers or personal computers (PCs). The computing device 800 can also be a mobile or stationary server.

[0190] The processor 820 executes the computer instructions to implement the steps of the above-described near-field communication method.

[0191] The above is an illustrative scheme of a computing device according to this embodiment. It should be noted that the technical solution of this computing device and the technical solution of the near-field communication method described above belong to the same concept. For details not described in detail in the technical solution of the computing device, please refer to the description of the technical solution of the near-field communication method described above.

[0192] An embodiment of this specification also provides a computer-readable storage medium storing computer instructions that, when executed by a processor, implement the steps of the near-field communication method as described above.

[0193] The above is an illustrative scheme of a computer-readable storage medium according to this embodiment. It should be noted that the technical solution of this storage medium belongs to the same concept as the technical solution of the near-field communication method described above. For details not described in detail in the technical solution of the storage medium, please refer to the description of the technical solution of the near-field communication method described above.

[0194] An embodiment of this specification also provides a computer program product, including a computer program / instructions that, when executed by a processor, implement the steps of the above-described near-field communication method.

[0195] The above is an illustrative scheme of a computer program product according to this embodiment. It should be noted that the technical solution of this computer program product and the technical solution of the near-field communication method described above belong to the same concept. For details not described in detail in the technical solution of the computer program product, please refer to the description of the technical solution of the near-field communication method described above.

[0196] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, for the embodiments of apparatus, devices, media, and products, since they are basically similar to the method embodiments, the descriptions are relatively simple, and relevant parts can be referred to the descriptions of the method embodiments. The apparatus, devices, media, products, and methods provided in the embodiments of this specification correspond to each other; therefore, the apparatus, devices, media, and products also have similar beneficial technical effects as the corresponding methods. Since the beneficial technical effects of the methods have been described in detail above, the beneficial technical effects of the corresponding apparatus, devices, media, and products will not be repeated here.

[0197] The foregoing has described specific embodiments of this specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in a different order than that shown in the embodiments and may still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require a specific or sequential order to achieve the desired result. In some embodiments, multitasking and parallel processing are possible or may be advantageous.

[0198] In the 1990s, improvements to a technology could be clearly distinguished as either hardware improvements (e.g., improvements to the circuit structure of diodes, transistors, switches, etc.) or software improvements (improvements to methodology). However, with technological advancements, many methodological improvements today can be considered direct improvements to hardware circuit structures. Designers almost always obtain the corresponding hardware circuit structure by programming the improved methodology into the hardware circuit. Therefore, it cannot be said that a methodological improvement cannot be implemented using hardware physical modules. For example, a Programmable Logic Device (PLD) (such as a Field Programmable Gate Array (FPGA)) is such an integrated circuit whose logic function is determined by the user programming the device. Designers can program a digital system themselves to "integrate" it onto a PLD, without needing chip manufacturers to design and manufacture dedicated integrated circuit chips. Furthermore, nowadays, instead of manually manufacturing integrated circuit chips, this programming is mostly implemented using "logic compiler" software. Similar to the software compiler used in program development, the original code before compilation must also be written in a specific programming language, called a Hardware Description Language (HDL). There are many HDLs, such as ABEL (Advanced Boolean Expression Language), AHDL (Altera Hardware Description Language), Confluence, CUPL (Cornell University Programming Language), HDCal, JHDL (Java Hardware Description Language), Lava, Lola, MyHDL, PALASM, and RHDL (Ruby Hardware Description Language). Currently, the most commonly used are VHDL (Very-High-Speed ​​Integrated Circuit Hardware Description Language) and Verilog. Those skilled in the art should also understand that by simply performing some logic programming on the method flow using one of these hardware description languages ​​and programming it into an integrated circuit, the hardware circuit implementing the logical method flow can be easily obtained.

[0199] The controller can be implemented in any suitable manner. For example, it can take the form of a microprocessor or processor and a computer-readable medium storing computer-readable program code (e.g., software or firmware) executable by the (micro)processor, logic gates, switches, application-specific integrated circuits (ASICs), programmable logic controllers, and embedded microcontrollers. Examples of controllers include, but are not limited to, the following microcontrollers: ARC 625D, Atmel AT91SAM, Microchip PIC18F26K20, and Silicon Labs C8051F320. A memory controller can also be implemented as part of the control logic of the memory. Those skilled in the art will also recognize that, in addition to implementing the controller in purely computer-readable program code form, the same functionality can be achieved by logically programming the method steps to make the controller take the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers. Therefore, such a controller can be considered a hardware component, and the means included therein for implementing various functions can also be considered as structures within the hardware component. Alternatively, the means for implementing various functions can be considered as both software modules implementing the method and structures within the hardware component.

[0200] The systems, devices, modules, or units described in the above embodiments can be implemented by computer chips or entities, or by products with certain functions. A typical implementation device is a computer. Specifically, a computer can be, for example, a personal computer, a laptop computer, a cellular phone, a camera phone, a smartphone, a personal digital assistant, a media player, a navigation device, an email device, a game console, a tablet computer, a wearable device, or any combination of these devices.

[0201] For ease of description, the above devices are described separately by function as various units. Of course, in implementing this application, the functions of each unit can be implemented in one or more software and / or hardware.

[0202] Those skilled in the art will understand that one or more embodiments of this specification can be provided as a method, system, or computer program product. Therefore, the invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0203] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0204] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0205] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0206] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0207] Memory may include non-persistent storage in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0208] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital character versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0209] This application can be described in the general context of computer-executable instructions, such as program modules, that are executed by a computer. Generally, program modules include routines, programs, objects, components, data structures, etc., that perform a specific task or implement a specific abstract data type. This application can also be practiced in distributed computing environments where tasks are performed by remote processing devices connected via a communication network. In distributed computing environments, program modules can reside in local and remote computer storage media, including storage devices.

[0210] The above description is merely an embodiment of this application and is not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A near-field communication method, applied to a slave device in near-field communication, the method comprising: Acquire the first radio frequency signal emitted by the master device of near-field communication; Determine whether the first radio frequency signal is a low-power signal; The low-power signal is a radio frequency signal emitted by the master device in low-power mode; If the first radio frequency signal is a low-power signal, then a first target modulated radio frequency signal that matches the first radio frequency signal is selected from multiple modulated radio frequency signals; The multiple modulated radio frequency signals are multiple radio frequency signals with different phases; The first target modulated radio frequency signal is transmitted for a first preset duration so that the master device exits the low power mode.

2. The method according to claim 1, wherein the first target modulated radio frequency signal is a radio frequency signal among the plurality of modulated radio frequency signals whose phase difference with the first radio frequency signal is less than or equal to a first preset threshold; or, the first target modulated radio frequency signal is a radio frequency signal among the plurality of modulated radio frequency signals whose phase difference with the first radio frequency signal is greater than or equal to a second preset threshold; Alternatively, the first target modulated radio frequency signal is the modulated radio frequency signal among the plurality of modulated radio frequency signals that has the closest phase to the first radio frequency signal; or, the first target modulated radio frequency signal is the modulated radio frequency signal among the plurality of modulated radio frequency signals that has the least phase to the first radio frequency signal.

3. The method according to claim 1, wherein selecting a first target modulated radio frequency signal that matches the first radio frequency signal from a plurality of modulated radio frequency signals comprises: The first radio frequency signal is superimposed on each of the modulated radio frequency signals to obtain each superimposed signal; Based on the envelope amplitude of each superimposed signal, a first target modulated radio frequency signal that matches the first radio frequency signal is determined.

4. The method according to claim 3, wherein determining the first target modulated radio frequency signal matching the first radio frequency signal based on the envelope amplitude of each superimposed signal comprises: From the various superimposed signals, determine the target superimposed signal with the largest envelope amplitude; The modulated radio frequency signal of the target superimposed signal is determined as the first target modulated radio frequency signal.

5. The method according to claim 3, further comprising: The first radio frequency signal is subjected to gain control processing to obtain a gain control radio frequency signal with a signal strength that meets the preset range; The step of superimposing the first radio frequency signal with each of the modulated radio frequency signals includes: The gain control radio frequency signal is superimposed on each of the modulation radio frequency signals.

6. The method according to claim 1, further comprising, after transmitting the first target modulated radio frequency signal for a first preset duration: Determine whether the main device has exited low-power mode; If the low-power mode has not been exited, the second radio frequency signal emitted by the master device is acquired; The second radio frequency signal is a radio frequency signal of another pulse emitted by the master device after the first radio frequency signal is sent; Based on the second radio frequency signal, a second target modulated radio frequency signal that matches the second radio frequency signal is selected from the plurality of modulated radio frequency signals; Transmit the second target modulated radio frequency signal for a second preset duration to facilitate the master device exiting the low-power mode.

7. The method according to claim 6, wherein the second target modulated radio frequency signal is a radio frequency signal among the plurality of modulated radio frequency signals whose phase difference with the second radio frequency signal is less than or equal to a third preset threshold; or, the second target modulated radio frequency signal is a radio frequency signal among the plurality of modulated radio frequency signals whose phase difference with the second radio frequency signal is greater than or equal to a fourth preset threshold; Alternatively, the second target modulated radio frequency signal is the modulated radio frequency signal among the plurality of modulated radio frequency signals whose phase is closest to that of the second radio frequency signal; or, the second target modulated radio frequency signal is the modulated radio frequency signal among the plurality of modulated radio frequency signals whose phase is least close to that of the second radio frequency signal.

8. The method according to claim 6, wherein the second preset duration is greater than the first preset duration; Alternatively, the first preset duration and / or the second preset duration may be less than the signal pulse duration of the low-power signal.

9. The method according to claim 6, further comprising, after transmitting the second target modulated radio frequency signal for a second preset duration: Determine whether the main device has exited low-power mode; If the master device has not exited the low-power mode, it sends a radio frequency excitation signal for a third preset duration.

10. The method according to any one of claims 1 to 9, wherein the plurality of modulated radio frequency signals are sorted according to their phase values, and the phase difference between adjacent modulated radio frequency signals is the same.

11. A near-field communication module, used as a slave device in near-field communication, the module comprising: Signal detection triggering unit, control unit, active modulation unit; The signal detection triggering unit is connected to the near-field antenna of the slave device and is used to acquire the first radio frequency signal emitted by the master device of near-field communication. If the first radio frequency signal is a low-power signal, a trigger signal is generated. The control unit is connected to the signal detection trigger unit and is used to acquire the trigger signal; The control unit is also connected to the active modulation unit and is used to control the active modulation unit to select a first target modulation radio frequency signal that matches the first radio frequency signal from multiple modulation radio frequency signals based on the trigger signal; The active modulation unit is connected to the near-field antenna; the near-field antenna is used to transmit the first target modulated radio frequency signal for a first preset duration so that the main device exits the low-power mode.

12. The module according to claim 11, wherein the signal detection triggering unit comprises a bandpass filter circuit, a buffer adjustment circuit, an RF power meter, and a comparison triggering circuit; The output of the bandpass filter circuit is connected to the input of the buffer adjustment circuit. The output terminal of the buffer adjustment circuit is connected to the input terminal of the radio frequency power meter; The output terminal of the radio frequency power meter is connected to the input terminal of the comparison trigger circuit; The signal detection triggering unit is connected to the near-field antenna of the slave device, including: the input terminal of the bandpass filter circuit is connected to the near-field antenna of the slave device; The control unit is connected to the signal detection trigger unit, including: the control unit is connected to the output terminal of the comparison trigger circuit.

13. The module according to claim 11, wherein the active modulation unit comprises a modulation signal circuit, an addition circuit, an envelope extraction circuit, a phase detection circuit, and a phase selection circuit; The output terminal of the modulation signal circuit is connected to the input terminal of the adder circuit; The modulation signal circuit is used to output the plurality of modulated radio frequency signals; The adder circuit is used to superimpose the plurality of modulated radio frequency signals onto the first radio frequency signal, respectively. The output terminal of the adder circuit is connected to the input terminal of the envelope extraction circuit; the envelope extraction circuit is used to extract the envelope amplitude of the superimposed signal obtained by superimposing the plurality of modulated radio frequency signals with the first radio frequency signal respectively; The electrical output terminal of the envelope extraction circuit is connected to the input terminal of the phase detection circuit; the phase detection circuit can determine the first target modulated radio frequency signal based on the envelope amplitude of the multiple superimposed signals. The output terminal of the phase detection circuit is connected to the input terminal of the control unit; The output terminal of the control unit is connected to the input terminal of the phase selection circuit; the control unit is used to control the phase selection circuit to select and activate the modulation circuit that can output the first target modulated radio frequency signal. The active modulation unit is connected to the near-field antenna, including: the output terminal of the phase selection circuit is connected to the near-field antenna so that the near-field antenna transmits the first target modulated radio frequency signal.

14. The module according to claim 13, wherein the active modulation unit further comprises a radio frequency switch; The input terminal of the radio frequency switch is connected to the near-field antenna to acquire the first radio frequency signal; The output terminal of the radio frequency switch and the output terminal of the modulation signal circuit are respectively connected to the input terminal of the adder circuit.

15. The module according to claim 14, wherein the active modulation unit further comprises a gain control circuit; the gain control circuit is used to perform gain control processing on the first radio frequency signal to obtain a gain control radio frequency signal with a signal strength conforming to a preset range; The output terminal of the radio frequency switch and the output terminal of the modulation signal circuit are respectively connected to the input terminal of the adder circuit, including: The output terminal of the radio frequency switch is connected to the input terminal of the gain control circuit; The output terminals of the gain control circuit and the modulation signal circuit are respectively connected to the input terminal of the adder circuit.

16. The module according to claim 14, wherein the active modulation unit further comprises a power amplifier circuit; the power amplifier circuit is used to amplify the original radio frequency signal output from the modulation circuit selected by the phase selection circuit to obtain the first target modulated radio frequency signal; The output of the phase selection circuit is connected to the near-field antenna, including: The output terminal of the phase selection circuit is connected to the input terminal of the power amplifier circuit; The output of the power amplifier circuit is connected to the near-field antenna via the radio frequency switch.

17. A near-field communication device, comprising: The signal acquisition module is used to acquire the first radio frequency signal emitted by the master device of near-field communication. The judgment module is used to determine whether the first radio frequency signal is a low-power signal; The low-power signal is a radio frequency signal emitted by the master device in low-power mode; A signal matching module is used to select a first target modulated radio frequency signal that matches the first radio frequency signal from a plurality of modulated radio frequency signals if the first radio frequency signal is a low-power signal. The multiple modulated radio frequency signals are multiple radio frequency signals with different phases; The signal transmitting module is used to transmit the first target modulated radio frequency signal for a first preset duration so that the master device exits the low power mode.

18. A near-field communication device, the device being used to perform the method of any one of claims 1 to 10, or the device comprising a module of any one of claims 11 to 16.

19. A computing device, comprising: Memory and processor; The memory is used to store computer programs / instructions, and the processor is used to execute the computer programs / instructions, which, when executed by the processor, implement the steps of the method according to any one of claims 1 to 10.

20. A computer-readable storage medium storing computer instructions that, when executed by a processor, implement the steps of the method according to any one of claims 1 to 10.

21. A computer program product comprising a computer program / instructions that, when executed by a processor, implement the steps of the method according to any one of claims 1 to 10.

Images