An electronic device

Abstract

The application provides an electronic device, comprising: a near field communication chip having a first output end and a second output end; a plurality of antennas, each of the plurality of antennas comprising a first end and a second end, the first end of each antenna being connected to the first output end, and the second end of each antenna being connected to the second output end, so that each antenna serves as a receiving loop of the near field communication chip.

Description

Technical Field

[0001] This application relates to an electronic device. Background Technology

[0002] In related technologies, near-field communication (NFC) chips typically output transmission signals through two output ports to drive a NFC antenna connected between these two output ports. In a differential driving method, the two output ports of the NFC chip output a first transmission signal and a second transmission signal, respectively. The differential antenna connected between these two output ports can form an induction loop based on the first and second transmission signals, thereby obtaining differential driving energy provided by both output ports.

[0003] However, in scenarios where terminal devices require multiple near-field communication antennas—for example, antennas placed at different locations on the device to adapt to different card-swiping postures, device forms, or the locations of different external card readers—the number of output ports of the near-field communication chip becomes a limitation. Figure 6 As shown, one antenna is connected as a differential antenna between two output ports of the near-field communication (NFC) chip, while another antenna is connected as a single-ended antenna between one of the NFC chip's output ports and a reference ground. In this scheme, because the differential antenna can simultaneously utilize the transmitted signals output from both output ports, while the single-ended antenna can typically only utilize the transmitted signal output from one output port, the transmitted energy obtained by the different antennas is not consistent. For example, the differential antenna connected between the two output ports can obtain the differential drive energy formed by the combined output signals from both ports, while the single-ended antenna connected between a single output port and the reference ground can only obtain the drive energy corresponding to that single output port.

[0004] Therefore, in multi-antenna near-field communication schemes, if a structure of "one differential antenna plus one or more single-ended antennas" is adopted, there will be inconsistencies in the driving methods and the transmitted energy obtained by different antennas. For single-ended antennas, since they cannot simultaneously utilize the transmitted signals output from both output ports of the near-field communication chip, it is difficult for the single-ended antenna to obtain transmitted energy close to the differential output capability of the chip, thus affecting the antenna's communication efficiency, near-field coupling capability, and user experience when performing near-field communication in different locations. Summary of the Invention

[0005] The purpose of this application is to provide an electronic device, including: A near-field communication chip, the near-field communication chip having a first output terminal and a second output terminal; Multiple antennas, each of the multiple antennas includes a first end and a second end, the first end of each antenna is connected to the first output end, and the second end of each antenna is connected to the second output end, so that each antenna serves as a sensing loop of the near-field communication chip; The near-field communication chip is configured to select one antenna from the plurality of antennas as the target antenna for communication, and output a first transmission signal in differential form through the first output terminal and a second transmission signal through the second output terminal. The target antenna receives more of the first transmission signal and the second transmission signal than the other antennas in the plurality of antennas, so that the transmission energy of the target antenna relative to the other antennas in the plurality of antennas is closer to the superposition of the transmission energy of the first transmission signal and the second transmission signal.

[0006] In some embodiments, the near-field communication chip is configured to select one antenna from the plurality of antennas as the target antenna for communication, including: The other antennas among the plurality of antennas are configured to be in an open-circuit state so that the first transmitted signal and the second transmitted signal flow into the target antenna.

[0007] In some embodiments, the near-field communication chip is configured to select one antenna from the plurality of antennas as the target antenna for communication, including: The electronic device is configured to include an adjustable module, which puts the target antenna in a low impedance state and the other antennas in a high impedance state, thereby concentrating the first transmission signal output from the first output terminal and the second transmission signal output from the second output terminal onto the target antenna. The adjustable module is used to adjust the impedance state of each of the plurality of antennas.

[0008] In some embodiments, the adjustable module belongs to a matching branch, the first end of the matching branch is connected to the first output terminal, the second end of the matching branch is connected to the second output terminal, and the matching branch is connected in parallel with each of the plurality of antennas.

[0009] In some embodiments, the adjustable module is an adjustable capacitor. Changing the capacitance value of the adjustable capacitor causes multiple antennas to present different equivalent impedance states at the target operating frequency of the near-field communication chip. The target operating frequency is the operating frequency of the first transmitted signal and the second transmitted signal.

[0010] In some embodiments, wherein By configuring the adjustable capacitor to a first capacitance value, the first LCR compensation circuit, the first antenna, and the adjustable capacitor in the first antenna branch are made to form a low input impedance matched state at the target operating frequency. At the same time, the second LCR compensation circuit, the second antenna, and the adjustable capacitor in the second antenna branch are made to form a high input impedance detuned state at the target operating frequency, so that the output current of the near-field communication chip preferentially flows into the first antenna branch, and the second antenna branch is approximately in an open circuit state due to its high input impedance. By configuring the adjustable capacitor to the second capacitance value, the second LCR compensation circuit, the second antenna, and the adjustable capacitor in the second antenna branch are made to form a low input impedance matching state at the target operating frequency, and the first LCR compensation circuit, the first antenna, and the adjustable capacitor in the first antenna branch are made to form a high input impedance detuning state at the target operating frequency. This causes the output current of the near-field communication chip to preferentially flow into the second antenna branch, and the first antenna branch is approximately in an open circuit state due to its high input impedance.

[0011] In some embodiments, the adjustable module comprises multiple adjustable sub-modules located within the near-field communication chip, and multiple control ports on the near-field communication chip corresponding to the multiple adjustable sub-modules are connected to the multiple antennas via multiple cables.

[0012] In some embodiments, the plurality of adjustable submodules are connected via a connection point on the near-field communication chip that is connected to ground representing the electronic device, and the adjustable submodule is an adjustable resistor; By configuring the corresponding adjustable submodules to different resistance values ​​through different control ports, the equivalent impedance of each of the multiple antennas at the target operating frequency of the near-field communication chip is changed. The target operating frequency is the operating frequency of the first transmission signal and the second transmission signal.

[0013] In some embodiments, a first control port is connected to a first antenna branch via a first cable, and the first adjustable resistor is configured as a controller for the first antenna branch; a second control port is connected to a second antenna branch via a second cable, and the second adjustable resistor is configured as a controller for the second antenna branch. in, By configuring the first adjustable resistor to a first resistance value and the second adjustable resistor to a second resistance value higher than the first resistance value, the near-field communication chip is configured to operate in a first antenna state. In the first antenna state, the first antenna branch is in a low equivalent impedance state at the target operating frequency, and the second antenna branch is in a high equivalent impedance state at the target operating frequency, so that the output current of the near-field communication chip preferentially flows into the first antenna branch. By configuring the first adjustable resistor to the second resistance value and the second adjustable resistor to the first resistance value, the near-field communication chip is configured to operate in the second antenna state. In the second antenna operating state, the second antenna branch is in a low equivalent impedance state at the target operating frequency, and the first antenna branch is in a high equivalent impedance state at the target operating frequency, so that the output current of the near-field communication chip preferentially flows into the second antenna branch.

[0014] In some embodiments, the near-field communication chip further includes a receiver, and each of the antennas is used to acquire signal parameters characterizing the strength of the received signal; The near-field communication chip is configured to alternately configure the parameters of the adjustable module in time, so that the multiple antennas are sequentially in a working state that can obtain all the transmitted energy, so as to obtain the signal parameters corresponding to each antenna respectively; The near-field communication chip determines the target antenna from the plurality of antennas based on the signal parameters and preset thresholds. The parameters of the adjustable module and the target antenna are maintained in a working state to obtain all the transmitted energy until the mission is completed. Attached Figure Description

[0015] In drawings that are not necessarily drawn to scale, the same reference numerals may describe similar parts in different views. The drawings generally illustrate various embodiments by way of example rather than limitation and are used, together with the description and claims, to illustrate the disclosed embodiments. Where appropriate, the same reference numerals are used in all drawings to refer to the same or similar parts. Such embodiments are illustrative and not intended to be exhaustive or exclusive embodiments of the apparatus or method.

[0016] Figure 1 This is a schematic diagram of the structure of an electronic device according to an embodiment of this application; Figure 2 This is a circuit diagram of the electronic device and adjustable module according to an embodiment of this application; Figure 3 The circuit diagram shows the electronic device and adjustable submodule according to an embodiment of this application; Figure 4 The circuit diagram shows an electronic device and an adjustable submodule according to another embodiment of this application; Figure 5 This is a flowchart illustrating the determination of the target antenna in an embodiment of this application; Figure 6 This is a circuit diagram of an electronic device that is prior art to this application.

[0017] in: ANT1, First antenna; ANT2, Second antenna; TX1, First output terminal; TX2, Second output terminal; C7, Adjustable capacitor; C8, Fixed capacitor; R01, First adjustable resistor; R02, Second adjustable resistor; Ctrl1, First control port; Ctrl2, Second control port. Detailed Implementation

[0018] To enable those skilled in the art to better understand the technical solution of this application, the application will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0019] The electronic device provided in this application includes: a near-field communication chip and multiple antennas. The near-field communication chip has a first output terminal and a second output terminal. Each of the multiple antennas includes a first terminal and a second terminal. The first terminal of each antenna is connected to the first output terminal, and the second terminal of each antenna is connected to the second output terminal, such that each antenna serves as a sensing loop of the near-field communication chip. The near-field communication chip is configured to select one antenna from the multiple antennas as a target antenna for communication, and output a first transmission signal in differential form through the first output terminal and a second transmission signal through the second output terminal. The target antenna receives more of the first transmission signal and the second transmission signal than other antennas in the multiple antennas, so that the transmission energy of the target antenna relative to other antennas in the multiple antennas is closer to the superposition of the transmission energy of the first transmission signal and the second transmission signal.

[0020] In this embodiment, each of the multiple antennas includes a first end and a second end. The first end of each antenna is connected to the first output terminal of the near-field communication chip, and the second end of each antenna is connected to the second output terminal of the near-field communication chip, so that each antenna can serve as an induction loop connected between the first and second output terminals. Therefore, compared to related technologies where one antenna uses a differential connection and another uses a single-ended connection, this application enables any antenna among the multiple antennas to utilize the differential driving energy formed by the first and second output terminals when selected as the target antenna, avoiding the situation where some antennas can only obtain single-ended driving energy because they are only connected to a single output port.

[0021] Furthermore, the near-field communication chip selects one antenna from multiple antennas as the target antenna for communication, enabling the target antenna to receive more of the first transmitted signal from the first output terminal and the second transmitted signal from the second output terminal compared to other antennas. Since the two ends of the target antenna are connected to the first and second output terminals respectively, the target antenna can form a differential induction loop based on the first and second transmitted signals, thereby allowing more differential driving energy provided by the two output ports to act on the target antenna. Therefore, it can improve the effective transmitted energy received by the target antenna, reduce the difference in transmission capability between antennas caused by single-ended connections, and improve the near-field coupling capability and communication efficiency of the target antenna in multi-antenna near-field communication scenarios.

[0022] For example, such as Figure 1 As shown, a smartphone (i.e., electronic device) with two NFC antennas has its first antenna ANT1 located at the top of the phone and its second antenna ANT2 located at the bottom. The first end of each antenna is connected to the first output terminal TX1 of the NFC chip (i.e., near-field communication chip), and the second end of each antenna is connected to the second output terminal TX2 of the NFC chip, forming two parallel sensing loops. When the user brings the top of the phone close to the card reader, the chip selects the first antenna ANT1 as the target antenna for communication.

[0023] Assume the total differential output power of the near-field communication chip is 2W (1W output from the first output terminal TX1 and 1W output from the second output terminal TX2). In related technologies, if a structure of "one differential antenna + one single-ended antenna" is adopted, the differential antenna can obtain approximately 2W of differential drive energy because it is connected to both the first output terminal TX1 and the second output terminal TX2. However, the single-ended antenna is only connected to one output terminal (such as the first output terminal TX1 or the second output terminal TX2), and can only obtain at most approximately 1W of single-ended drive energy. This results in a severe imbalance in the transmission energy obtained by the two antennas, affecting the communication performance of the single-ended antenna.

[0024] In this application, since each antenna is differentially connected to the first output terminal TX1 and the second output terminal TX2, the selected target antenna (such as the first antenna ANT1) receives most of the differential drive current, that is, the target antenna can obtain a total transmission energy of nearly 2W, while the other antenna (such as the second antenna ANT2) receives almost no transmission energy (close to 0W), thereby ensuring that any selected target antenna can obtain transmission energy that matches the differential output capability of the chip.

[0025] In one embodiment, the near-field communication chip is configured to select one antenna from the plurality of antennas as a target antenna for communication, including configuring the other antennas among the plurality of antennas to be in an open-circuit state, so that the first transmitted signal and the second transmitted signal flow into the target antenna.

[0026] In this embodiment of the application, by configuring the antennas other than the target antenna among the multiple antennas to be in an open circuit state, the first transmission signal and the second transmission signal output by the first output terminal TX1 and the second output terminal TX2 cannot form a current loop in the other antenna branches, thereby forcing the differential drive current to mainly flow through the target antenna.

[0027] Since the first and second ends of the target antenna are connected to the first and second output ends respectively, the differential drive current forms a complete induction loop on the target antenna, enabling the target antenna to obtain differential drive energy jointly provided by the first and second transmitted signals. Thus, through open-circuit control, the differential drive energy is simply and effectively concentrated and distributed to the target antenna, avoiding the dispersion of transmitted energy among multiple antenna branches and ensuring that the target antenna receives sufficient transmitted energy for near-field communication.

[0028] In circuit theory, the open-circuit state refers to a path where current cannot flow. In this embodiment, the "open-circuit state" is an "equivalent open circuit," not a physical disconnection of other antenna branches from the loop using switching devices. Compared to schemes that use physical switches to switch antennas, this application does not require disconnecting any physical connections; all antenna branches remain conductive in the circuit structure at all times.

[0029] This application completely cuts off the shunt channel for non-target antennas in the energy distribution path, ensuring that all transmitted energy is concentrated on the target antenna. The implementation does not rely on physical switches and requires no disconnection of any physical connections. All antenna branches remain physically connected at all times, and the switching process is smooth and without mechanical movement.

[0030] In one embodiment, such as Figure 2 As shown, the near-field communication chip is configured to select one antenna from the plurality of antennas as the target antenna for communication, including: configuring an adjustable module included in the electronic device to make the target antenna in a low impedance state and the other antennas in a high impedance state, thereby concentrating the first transmission signal output through the first output terminal TX1 and the second transmission signal output through the second output terminal TX2 to the target antenna, wherein the adjustable module is used to adjust the impedance state of each of the plurality of antennas.

[0031] In this embodiment, an adjustable module is incorporated into the electronic device to adjust the impedance state of each of the multiple antennas. When a target antenna needs to be selected from the multiple antennas, the adjustable module is configured to place the target antenna in a low-impedance state while simultaneously placing the other antennas in a high-impedance state. Since current preferentially flows to the branch with lower impedance in a parallel branch, the current corresponding to the transmitted signal output by the first output terminal TX1 and the second output terminal TX2 of the near-field communication chip will be concentrated and distributed to the target antenna branch with lower impedance.

[0032] Meanwhile, other antennas, due to their high impedance, are approximately equivalent to open circuits and receive almost no transmission current. Therefore, through an impedance regulation mechanism, differential drive energy can be distributed on demand among multiple antennas without the need for physical switching, enabling the target antenna to receive transmission energy close to the total differential drive energy. This improves the transmission efficiency and communication performance of the target antenna in a multi-antenna near-field communication system.

[0033] The adjustable module is a controllable element or circuit used to adjust the impedance state of each antenna branch, and is not a switching device. The adjustable module functions to continuously adjust the impedance value, rather than switching the antenna branches on or off.

[0034] The low impedance state refers to the antenna branch exhibiting a small equivalent impedance value at the target operating frequency, making it easy for current to flow into the branch. The high impedance state refers to the antenna branch exhibiting a large equivalent impedance value at the target operating frequency, making it difficult for current to flow into the branch.

[0035] The antenna switching process in this application is flexible and controllable; switching between different antennas can be achieved by adjusting the parameters of the adjustable module. No physical disconnection of any branch is required, and all antennas maintain electrical connection at all times.

[0036] In one embodiment, such as Figure 2 As shown, the adjustable module belongs to the matching branch. The first end of the matching branch is connected to the first output terminal TX1, and the second end of the matching branch is connected to the second output terminal TX2. The matching branch is connected in parallel with each of the plurality of antennas.

[0037] In this embodiment, the adjustable module is configured as part of a matching branch. The first end of the matching branch is connected to the first output terminal TX1 of the near-field communication chip, and the second end of the matching branch is connected to the second output terminal TX2 of the near-field communication chip. This matching branch is connected in parallel with each antenna branch. By placing the adjustable module in the matching branch, the adjustable module can simultaneously participate in the formation of the impedance matching state of each antenna branch.

[0038] Because the matching branch is connected in parallel with all antenna branches, changes in the parameters of the adjustable module will simultaneously affect the equivalent impedance of each antenna branch. This allows for differentiated control of the impedance states of different antenna branches by adjusting the adjustable module in the matching branch, without the need for individual control switches for each antenna. This simplifies the structural complexity of multi-antenna impedance control and reduces the number of components and cost of the electronic equipment.

[0039] In one embodiment, such as Figure 2 As shown, the adjustable module is an adjustable capacitor C7. By changing the capacitance value of the adjustable capacitor C7, multiple antennas can present different equivalent impedance states at the target operating frequency of the near-field communication chip. The target operating frequency is the operating frequency of the first transmission signal and the second transmission signal.

[0040] In this embodiment, the adjustable module is specifically configured as an adjustable capacitor C7. By changing the capacitance value of the adjustable capacitor C7, multiple antenna branches exhibit different equivalent impedance states at the target operating frequency of the near-field communication chip. Since the change in capacitance value alters the impedance characteristics of the matching branch, it affects the resonant state and equivalent impedance of each antenna branch connected in parallel with the matching branch at a specific frequency. The antenna branch exhibits low impedance when in a resonant matching state at the target operating frequency, and high impedance when in a detuned state.

[0041] Therefore, by changing the capacitance value of the adjustable capacitor C7, a specific target antenna branch can be selectively made to exhibit a low impedance matching state at the target operating frequency, while other antenna branches exhibit a high impedance detuning state. Thus, a simple adjustable capacitor enables selective control of the impedance state of different antenna branches at the target operating frequency, allowing the differential drive energy output by the near-field communication chip to be distributed to the target antenna branch.

[0042] The equivalent impedance state refers to the overall impedance characteristics of an antenna branch at the target operating frequency, determined by all components within that branch (inductors, capacitors, resistors, and the antenna itself). It should be noted that each antenna branch has its own compensation circuit (e.g., an LCR compensation network). Due to differences in the physical structure, routing, and parameters and quantities of the compensation components (inductors, capacitors, resistors) used in different antenna branches, each antenna branch exhibits different impedance bandwidth characteristics (i.e., different Q values) near the target operating frequency. In other words, at the same target operating frequency, each antenna branch exhibits different passband widths—some branches have wide passband characteristics (lower equivalent impedance, allowing current to pass easily), while others have narrow passband characteristics (higher equivalent impedance, making it difficult for current to pass).

[0043] When the capacitance value of the adjustable capacitor C7 is changed, it forms different filter network combinations with the compensation circuits of each antenna branch. For a certain branch, when the current capacitance value of the adjustable capacitor C7 is combined with the compensation circuit of that branch to make it exhibit wide passband characteristics at the target operating frequency, the equivalent impedance of that branch is low, and the differential current preferentially flows into that branch, so the antenna corresponding to that branch obtains the main transmission energy. Other branches, because the current capacitance value of the adjustable capacitor C7 is combined with its compensation circuit to exhibit narrow passband or even stopband characteristics, have high equivalent impedance, and the current flowing through them is extremely small, which is equivalent to an open circuit state.

[0044] Based on the above principle, by simply adjusting the capacitance value of a single adjustable capacitor C7, different antenna branches can exhibit differentiated states of broadband / narrowband (i.e., low impedance / high impedance) at the target operating frequency, thereby achieving the selection and switching of different antennas. Throughout the entire process, all antenna branches remain physically connected and no switching devices are used for on / off control.

[0045] For example, when the adjustable capacitor C7 is 1pF, the first antenna branch has low impedance (matched) at 13.56MHz, and the second antenna branch has high impedance (detuned); when the adjustable capacitor C7 is 10pF, the situation is reversed.

[0046] In one embodiment, such as Figure 2 As shown, by configuring the adjustable capacitor C7 to the first capacitance value, the first LCR compensation circuit, the first antenna ANT1, and the adjustable capacitor C7 in the first antenna branch are made to form a low input impedance matched state at the target operating frequency. At the same time, the second LCR compensation circuit, the second antenna ANT2, and the adjustable capacitor C7 in the second antenna branch are made to form a high input impedance detuned state at the target operating frequency, so that the output current of the near-field communication chip preferentially flows into the first antenna branch, and the second antenna branch is approximately in an open circuit state due to its high input impedance.

[0047] By configuring the adjustable capacitor C7 to the second capacitance value, the second LCR compensation circuit, the second antenna ANT2, and the adjustable capacitor C7 in the second antenna branch are made to form a low input impedance matching state at the target operating frequency, and the first LCR compensation circuit, the first antenna ANT1, and the adjustable capacitor C7 in the first antenna branch are made to form a high input impedance detuning state at the target operating frequency. This causes the output current of the near-field communication chip to preferentially flow into the second antenna branch, and the first antenna branch is approximately in an open circuit state due to its high input impedance.

[0048] In this embodiment of the application, in an electronic device having a first antenna branch and a second antenna branch, by configuring the adjustable capacitor to a first capacitance value, the first antenna branch, which is composed of a first LCR compensation circuit, a first antenna, and an adjustable capacitor, is in a low input impedance matching state at the target operating frequency, while the second antenna branch, which is composed of a second LCR compensation circuit, a second antenna, and an adjustable capacitor, is in a high input impedance detuning state at the target operating frequency.

[0049] Current preferentially flows to the low-impedance branch, causing the output current of the near-field communication chip to preferentially flow into the first antenna branch. Conversely, by configuring the adjustable capacitor C7 to the second capacitance value, the output current can preferentially flow into the second antenna branch.

[0050] Therefore, by simply changing the capacitance value of an adjustable capacitor C7, the differential drive energy can be preferentially allocated and flexibly switched between the two antenna branches, so that the selected target antenna branch can obtain almost all the differential drive energy, ensuring that different antennas have consistent transmission capabilities when selected as target antennas.

[0051] The first capacitance value and the second capacitance value are two different capacitance values ​​(e.g., 1pF and 10pF) configured for the adjustable capacitor C7, corresponding to two operating states where the first antenna ANT1 and the second antenna ANT2 are selected as the target antennas, respectively. The first antenna branch is equipped with a first LCR compensation circuit (including inductors and resistors, etc.), and the second antenna branch is equipped with a second LCR compensation circuit (including inductors, resistors, etc., and a fixed capacitor C8, etc.). The fixed capacitor C8 is located in the second antenna branch, and its function is to make the compensation parameters of the two branches different, thereby realizing differentiated control of the two branches by a single adjustable capacitor C7.

[0052] In this embodiment, when the first antenna ANT1 is selected, the adjustable capacitor C7 is configured to a first capacitance value (e.g., 1pF). At this time, the adjustable capacitor C7, the first LCR compensation circuit, and the first antenna ANT1 together form a low input impedance matching state at the target operating frequency; simultaneously, the adjustable capacitor C7, the second LCR compensation circuit, and the second antenna ANT2 form a high input impedance detuned state. The chip output current preferentially flows into the first antenna branch, and the second antenna branch is approximately open-circuited due to high impedance. When the second antenna ANT2 is selected, the adjustable capacitor C7 is configured to a second capacitance value (e.g., 10pF). At this time, the adjustable capacitor C7, the second LCR compensation circuit, and the second antenna ANT2 form a low input impedance matching state; the adjustable capacitor C7, the first LCR compensation circuit, and the first antenna ANT1 form a high input impedance detuned state. The chip output current preferentially flows into the second antenna branch, and the first antenna branch is approximately open-circuited due to high impedance.

[0053] The different LCR compensation circuit parameters of the two branches result in different impedance bandwidth characteristics (Q values) at the target operating frequency. Different values ​​of the adjustable capacitor C7, when combined with the two branches, create differentiated wide / narrow passband states. It should be noted that the first and second capacitor values ​​mentioned above are exemplary values; the actual values ​​depend on the compensation circuit parameters of each antenna branch, and those skilled in the art can determine them through conventional experiments based on the target operating frequency and the actual impedance characteristics of each branch.

[0054] In one embodiment, such as Figure 3 As shown, the adjustable module consists of multiple adjustable sub-modules located within the near-field communication chip, and multiple control ports on the near-field communication chip corresponding to the multiple adjustable sub-modules are connected to the multiple antennas via multiple cables.

[0055] In this embodiment, the adjustable module is implemented as multiple adjustable sub-modules located inside the near-field communication chip, and each adjustable sub-module is connected to the corresponding antenna through a control port on the near-field communication chip and a corresponding cable. Integrating the adjustable sub-modules inside the near-field communication chip allows the impedance adjustment function to be implemented inside the chip, eliminating the need for additional adjustable components outside the chip, thereby saving layout space on the printed circuit board and reducing the design complexity of the external circuit.

[0056] Meanwhile, multiple control ports on the chip are connected to multiple antennas via multiple cables, enabling each adjustable submodule inside the chip to independently control its corresponding antenna branch, thus improving the flexibility and accuracy of independently configuring the impedance states of multiple antennas.

[0057] The adjustable submodule is an impedance-adjustable element located inside the NFC chip. The control port is a pin on the NFC chip used for external connections, corresponding to the adjustable submodule inside the chip. Through this port, the adjustable resources inside the chip can be connected to external antenna branches. The chip independently configures the impedance parameters of the corresponding adjustable submodule through each control port, thereby changing the equivalent impedance state of each antenna branch at the target operating frequency—making the target antenna branch exhibit low impedance and other branches exhibit high impedance.

[0058] In one embodiment, such as Figure 3 As shown, the plurality of adjustable submodules are connected to the ground of the electronic device through the connection point on the near-field communication chip. The adjustable submodule is an adjustable resistor. By configuring the corresponding adjustable submodule to different resistance values ​​through different control ports, the equivalent impedance of each of the plurality of antennas at the target operating frequency of the near-field communication chip is changed. The target operating frequency is the operating frequency of the first transmitted signal and the second transmitted signal.

[0059] In this embodiment, multiple adjustable sub-modules within the near-field communication chip are grounded through connection points on the chip that represent the ground of the electronic device, and each adjustable sub-module is specifically an adjustable resistor. By configuring different resistance values ​​for the corresponding adjustable resistors through different control ports, the equivalent impedance of the antenna branch connected to each control port at the target operating frequency can be changed within the chip.

[0060] Because changes in the resistance of the adjustable resistor alter the equivalent load characteristics of the corresponding antenna branch within the chip, thus affecting the input impedance of the entire antenna branch, independent and precise adjustment of the equivalent impedance of multiple antenna branches can be achieved by configuring the resistance value of the adjustable resistor within the chip. This eliminates the need for adjustable components in the external antenna matching network, further simplifying external circuit design and improving the response speed and reliability of impedance adjustment.

[0061] The chip configures the corresponding adjustable resistors to different resistance values ​​(e.g., one with a low resistance and the other with a high resistance) through different control ports. Due to the different resistance values ​​of the adjustable resistors, the equivalent impedance of each antenna branch at the target operating frequency is changed—the branch corresponding to the low resistance value exhibits a low equivalent impedance (current flows in easily), while the branch corresponding to the high resistance value exhibits a high equivalent impedance (current is suppressed).

[0062] In one embodiment, such as Figure 3 As shown, the first control port Ctrl1 is connected to the first antenna branch via a first cable, and the first adjustable resistor R01 is configured as the controller of the first antenna branch; the second control port Ctrl2 is connected to the second antenna branch via a second cable, and the second adjustable resistor R02 is configured as the controller of the second antenna branch.

[0063] Specifically, by configuring the first adjustable resistor R01 to a first resistance value and the second adjustable resistor R02 to a second resistance value higher than the first resistance value, the near-field communication chip is configured to operate in the first antenna ANT1 state. In the first antenna ANT1 operating state, the first antenna branch is in a low equivalent impedance state at the target operating frequency, and the second antenna branch is in a high equivalent impedance state at the target operating frequency, so that the output current of the near-field communication chip preferentially flows into the first antenna branch.

[0064] By configuring the first adjustable resistor R01 to the second resistance value and the second adjustable resistor R02 to the first resistance value, the near-field communication chip is configured to operate in the second antenna ANT2 state. In the second antenna ANT2 operating state, the second antenna branch is in a low equivalent impedance state at the target operating frequency, and the first antenna branch is in a high equivalent impedance state at the target operating frequency, so that the output current of the near-field communication chip preferentially flows into the second antenna branch.

[0065] In this embodiment of the application, in an electronic device having a first antenna branch and a second antenna branch, a first cable connects a first control port to the first antenna branch, and a first adjustable resistor serves as a controller for the first antenna branch; a second cable connects a second control port to the second antenna branch, and a second adjustable resistor serves as a controller for the second antenna branch.

[0066] When the first antenna needs to be selected as the target antenna, the first adjustable resistor is configured to a lower first resistance value, and the second adjustable resistor is configured to a higher second resistance value. This causes the first antenna branch to exhibit a low equivalent impedance state at the target operating frequency, while the second antenna branch exhibits a high equivalent impedance state. Consequently, the output current of the near-field communication chip preferentially flows into the first antenna branch. Conversely, by swapping the resistance values ​​of the two adjustable resistors, the output current can preferentially flow into the second antenna branch.

[0067] Therefore, by simply switching the resistance values ​​of the two adjustable resistors inside the chip, the target antenna can be flexibly switched between the two antenna branches, ensuring that the selected target antenna obtains almost all the differential drive current at the target operating frequency, thereby obtaining transmission energy close to the superposition of differential drive energy, ensuring consistent near-field communication performance under different antenna positions.

[0068] For example, when the first antenna ANT1 is selected, the first adjustable resistor R01 is configured with a first resistance value (low resistance, such as 10Ω), and the second adjustable resistor R02 is configured with a second resistance value (high resistance, such as 1000Ω). The first antenna branch exhibits a low equivalent impedance at the target operating frequency, while the second antenna branch exhibits a high equivalent impedance. The chip output current preferentially flows into the first antenna branch. When the second antenna ANT2 is selected, the first adjustable resistor R01 is configured with a second resistance value (high resistance, such as 1000Ω), and the second adjustable resistor R02 is configured with a first resistance value (low resistance, such as 10Ω). The second antenna branch exhibits a low equivalent impedance, while the first antenna branch exhibits a high equivalent impedance. The chip output current preferentially flows into the second antenna branch.

[0069] In another embodiment, such as Figure 4As shown, the near-field communication chip integrates multiple adjustable sub-modules and corresponding control ports. The adjustable resistors are connected in series to each antenna branch, without needing to be connected to a reference ground. The first control port Ctrl1 of the near-field communication chip is connected to the first antenna branch via a first cable, connecting the internal first adjustable resistor R01 in series with that branch; the second control port Ctrl2 is connected to the second antenna branch via a second cable, connecting the internal second adjustable resistor R02 in series with that branch. Each adjustable resistor acts as a series control device for its corresponding antenna branch; by changing its resistance value, the total equivalent impedance of that branch at the target operating frequency can be directly changed without requiring a grounding loop for adjustment.

[0070] In this embodiment, the adjustable resistors are directly connected in series to the signal paths of each antenna branch, rather than to a reference ground. This allows the resistance changes of the adjustable resistors to be directly added to the total equivalent impedance of the corresponding antenna branch. Compared to schemes that rely on a ground loop for impedance regulation, the series control method in this embodiment does not depend on the internal ground port of the chip and is not affected by fluctuations in the reference ground potential, enabling more direct and precise control of the impedance state of each antenna branch. Furthermore, since there is no need to provide a ground connection for each adjustable resistor, the internal circuit design of the chip and the external PCB layout are simplified, which is beneficial for the miniaturization and high-density integration of terminal devices.

[0071] For example, when the first adjustable resistor R01 is configured to a first resistance value (low resistance, such as 10Ω) and the second adjustable resistor R02 is configured to a second resistance value (high resistance, such as 1000Ω), the total equivalent impedance of the first antenna branch is low because the series resistance is directly superimposed on the total impedance of the branch, while the total equivalent impedance of the second antenna branch is high. The differential output current preferentially flows into the first antenna branch with lower impedance, and the first antenna ANT1 is selected. At this time, the first adjustable resistor R01, due to its low resistance, has a small impediment effect on the differential signal current, allowing most of the differential drive current to pass smoothly through the first antenna branch, thus enabling the first antenna ANT1 to obtain transmission energy close to the total differential output power of the chip; while the second adjustable resistor R02, due to its high resistance, has a large impediment effect on the differential signal current, resulting in almost no current flowing through the second antenna branch, and the second antenna ANT2 obtaining transmission energy close to 0W.

[0072] Conversely, when the first adjustable resistor R01 is configured to the second resistance value (high resistance) and the second adjustable resistor R02 is configured to the first resistance value (low resistance), the total equivalent impedance of the second antenna branch is lower, and the differential output current preferentially flows into the second antenna branch, thus selecting the second antenna ANT2. At this time, the differential drive energy is concentrated and distributed to the second antenna branch, enabling the second antenna ANT2 to obtain transmission energy close to the total differential output power of the chip.

[0073] Compared to related technologies that require switching switches between multiple antenna branches to select an antenna, this embodiment achieves target antenna selection and centralized distribution of differential drive energy simply by configuring the resistance value of an adjustable resistor connected in series within the chip, eliminating the need for any external switching devices. Throughout the switching process, all antenna branches remain physically connected, without any switching devices for on / off control. Switching the target antenna only requires changing the resistance value of the adjustable resistor, eliminating transient shocks and signal interruptions caused by switching on and off. The switching process is smooth and continuous, improving the stability and reliability of near-field communication.

[0074] In one embodiment, such as Figure 5 As shown, the near-field communication chip also has a receiver, and each of the antennas is used to acquire signal parameters characterizing the strength of the received signal; the near-field communication chip is configured to alternately configure the parameters of the adjustable module in time, so that the plurality of antennas are sequentially in a working state capable of acquiring all the transmitted energy, so as to acquire the signal parameters corresponding to each antenna respectively; the near-field communication chip determines the target antenna from the plurality of antennas according to each of the signal parameters and a preset threshold; and maintains the parameters of the adjustable module and the working state of the target antenna acquiring all the transmitted energy until the task is completed.

[0075] In this embodiment, the near-field communication chip also includes a receiver, and each antenna can be used to acquire signal parameters characterizing the received signal strength. The near-field communication chip alternately configures the parameters of the adjustable module over time, causing multiple antennas to sequentially take turns being in a working state capable of acquiring all differential transmission energy, and acquiring signal parameters such as the received signal strength corresponding to each antenna in each state. Then, the near-field communication chip compares the signal parameters corresponding to each antenna with a preset threshold, selecting the antenna whose signal parameters meet the requirements as the target antenna. After determining the target antenna, the current parameter configuration of the adjustable module is maintained, ensuring that the target antenna remains in a working state capable of acquiring all differential transmission energy until the current near-field communication task is completed.

[0076] Therefore, by dynamically detecting the received signal quality of each antenna, the target antenna is intelligently selected and switched, enabling electronic devices to adaptively select the antenna with the best signal conditions for near-field communication based on the actual communication environment. This improves the environmental adaptability and communication success rate of the multi-antenna near-field communication system, and enhances the user's communication experience under different card-swiping postures and device usage scenarios.

[0077] For example, the mobile phone has two antennas: a first antenna ANT1 and a second antenna ANT2. The chip alternately configures an adjustable module (such as an adjustable capacitor C7) to sequentially put the first antenna ANT1 and the second antenna ANT2 into an energy-concentrated state, and measures their respective RSSI values. If the RSSI value of the first antenna ANT1 is -45dBm (exceeding the preset threshold of -60dBm), and the RSSI value of the second antenna ANT2 is -75dBm (below the threshold), then the chip selects the first antenna ANT1 as the target antenna and locks that state until the transaction is completed.

[0078] This application implements complete closed-loop control of intelligent antenna selection and state locking. This enables the entire multi-antenna system to possess adaptive and automated communication capabilities—automatically selecting the optimal antenna without user intervention. Once the target is determined, the state is locked, avoiding signal interruptions or instability caused by frequent switching during communication.

[0079] In summary, this application, during its operation, if Figure 2 As shown, the near-field communication chip has a first output terminal TX1 and a second output terminal TX2. A matching branch (including an adjustable capacitor C7), a first antenna branch (including a first LCR compensation circuit and a first antenna ANT1, etc.), and a second antenna branch (including a second LCR compensation circuit, a fixed capacitor C8, and a second antenna ANT2, etc.) are connected in parallel between the first output terminal TX1 and the second output terminal TX2. All antenna branches remain physically connected at all times, without any physical switches.

[0080] When an electronic device needs to perform NFC communication or is powered on, the near-field communication chip first enters the antenna selection phase. The chip alternately configures the adjustable capacitor C7 to different values ​​over time, ensuring that the two antenna branches are sequentially in a working state capable of receiving full transmission energy. The chip configures the adjustable capacitor C7 to the first capacitance value, making the first antenna branch low impedance (gaining all energy), while the second antenna branch is high impedance (equivalent to an open circuit). The chip obtains the received signal strength parameters (such as RSSI value) sensed by the first antenna ANT1 in the current state through the receiver (such as RX1, RX2) and records these parameters.

[0081] The chip then configures the adjustable capacitor C7 to the second capacitance value, making the second antenna branch low impedance (gaining all energy) and the first antenna branch high impedance (equivalent to an open circuit). The chip acquires the RSSI value sensed by the second antenna ANT2 in the current state and records this parameter.

[0082] The chip compares the two RSSI values ​​with preset thresholds respectively, and determines the antenna with better signal quality (such as a larger RSSI value or exceeding the preset threshold) as the target antenna for this communication.

[0083] For ease of explanation, assume that the first antenna ANT1 is determined to be the target antenna. Based on the selection result of the target antenna, the chip maintains the first capacitance value configured for the adjustable capacitor C7 (corresponding to the capacitance value selected for the first antenna ANT1, for example, 1pF).

[0084] At this capacitance value, the first LCR compensation circuit, the first antenna ANT1, and the adjustable capacitor C7 in the first antenna branch together form a low input impedance matching state (resonance state) at the target operating frequency (e.g., 13.56MHz). The equivalent impedance of this branch is low, and current flows in easily.

[0085] The second LCR compensation circuit, fixed capacitor C8, second antenna ANT2, and adjustable capacitor C7 in the second antenna branch together form a detuned state with high input impedance at the target operating frequency. The equivalent impedance of this branch is extremely high, and the current flowing through it is extremely small, which is equivalent to an open circuit.

[0086] Due to the impedance difference between the two branches (low impedance for the first antenna ANT1 and high impedance for the second antenna ANT2), high-frequency current preferentially flows along the low-impedance path. The differential transmit signal current output by the near-field communication chip through the first output terminal TX1 and the second output terminal TX2 preferentially flows into the first antenna branch. The current in the second antenna branch is extremely small due to its high impedance and can be ignored.

[0087] Therefore, the target antenna (first antenna ANT1) receives more energy from the first and second transmitted signals compared to the other antennas (second antenna ANT2), and its actual transmitted energy approaches the complete superposition of the transmitted energy from the first output terminal TX1 and the transmitted energy from the second output terminal TX2 (i.e., the total power is maximized). Meanwhile, the non-target antenna (second antenna ANT2) fails to obtain significant energy due to its high impedance equivalent open circuit.

[0088] After identifying the target antenna, the chip maintains the current first capacitance value of the adjustable capacitor C7 without switching it, ensuring that the first antenna ANT1 remains in a state where it receives all transmission energy. This locked state continues until the current card reading or communication task is completed. After the task is completed, the chip can re-enter polling to handle scenarios such as changes in device attitude.

[0089] It should be noted that the above implementation using adjustable capacitor C7 as the adjustable module is merely an example. In another set of parallel implementations, the adjustable module can also be implemented using multiple adjustable resistors located inside the near-field communication chip. Depending on the connection method between the adjustable resistors and the antenna branch, this can be further divided into the following two parallel implementation methods: In another embodiment, such as Figure 3As shown, the adjustable resistors are connected in parallel between each antenna branch and the reference ground. One end of each adjustable resistor is connected to the corresponding control port, and the other end is connected to the reference ground. By adjusting the resistance value of each grounding resistor, the equivalent impedance of each branch to ground is changed.

[0090] Specifically, the near-field communication chip integrates multiple adjustable sub-modules, each with a corresponding control port. One end of each adjustable resistor is connected to its corresponding control port (connected to each antenna branch via a cable), and the other end is connected to reference ground (GND, the connection point representing the earth of the electronic device). Each antenna branch is connected to ground via the control port and the adjustable resistor, i.e., in parallel. All antenna branches remain physically connected at all times, without any physical switches.

[0091] When NFC communication is required, the chip enters the antenna selection phase. The chip alternately configures the resistance combinations of the first adjustable resistor R01 and the second adjustable resistor R02 in time, ensuring that the two antenna branches are sequentially in a working state capable of receiving full transmission energy. The chip configures the first adjustable resistor R01 connected to the first antenna branch to a low resistance value (e.g., 10Ω), and the second adjustable resistor R02 connected to the second antenna branch to a high resistance value (e.g., 1000Ω), so that the first antenna branch has a low equivalent impedance (to obtain all energy) at the target operating frequency, and the second antenna branch has a high equivalent impedance. The chip obtains the RSSI value of the first antenna ANT1 in the current state through the receiver and records this parameter.

[0092] The chip then swaps the resistance values ​​of the two resistors—setting the first adjustable resistor R01, connected to the first antenna branch, to a high resistance value, and setting the second adjustable resistor R02, connected to the second antenna branch, to a low resistance value, so that the second antenna branch has a low equivalent impedance (gaining all energy) and the first antenna branch has a high equivalent impedance. The chip obtains the RSSI value of the second antenna ANT2 in the current state and records this parameter.

[0093] The chip compares the two RSSI values ​​with preset thresholds and determines the antenna with the better signal quality as the target antenna for this communication. Let's assume the first antenna, ANT1, is determined as the target antenna.

[0094] Based on the target antenna selection result, the chip configures the first adjustable resistor R01 connected to the first antenna branch to a low resistance value and the second adjustable resistor R02 connected to the second antenna branch to a high resistance value.

[0095] With this resistance configuration, the equivalent impedance of the first antenna branch at the target operating frequency is low. Current easily flows into this branch, and the first antenna ANT1 obtains the main transmission energy. The equivalent impedance of the second antenna ANT2 at the target operating frequency is high. This branch has extremely high impedance, and the current flowing through it is minimal, equivalent to an open circuit.

[0096] Due to the impedance difference between the two branches, the differential transmit signal current output by the near-field communication chip through the first output terminal TX1 and the second output terminal TX2 preferentially flows into the first antenna branch. The current in the second antenna branch is negligible due to its high impedance. Therefore, the target antenna, the first antenna ANT1, obtains transmit energy approaching the total power of the first output terminal TX1 and the second output terminal TX2.

[0097] After identifying the target antenna ANT1, the chip maintains the current resistance values ​​of the two adjustable resistors without switching them, ensuring that ANT1 remains in a state where it receives all transmission energy. This locked state continues until the communication mission is completed. After the mission is completed, the chip can re-enter the polling detection phase.

[0098] In yet another embodiment, such as Figure 4 As shown, the adjustable resistors are connected in series in each antenna branch and do not need to be connected to a reference ground. By adjusting the resistance value of each series resistor, the total equivalent impedance of each branch can be directly changed.

[0099] Specifically, the near-field communication chip integrates multiple adjustable sub-modules, each with a corresponding control port. The first control port Ctrl1 is connected in series via a cable to the first antenna branch (including the first antenna ANT1), with the first adjustable resistor R01 connected in series in this branch. The second control port Ctrl2 is connected in series via a cable to the second antenna branch (including the second antenna ANT2), with the second adjustable resistor R02 connected in series in this branch. Each adjustable resistor does not need to be connected to a reference ground; it directly acts as a series impedance element to adjust the total impedance of each branch. All antenna branches remain physically connected at all times, without any physical switches.

[0100] When NFC communication is required, the chip enters the antenna selection phase. The chip alternately configures the resistance combinations of two adjustable resistors over time, ensuring that the two antenna branches are sequentially in an operating state capable of receiving full transmission energy. The chip configures the first adjustable resistor R01 to a low resistance value (e.g., 10Ω) and the second adjustable resistor R02 to a high resistance value (e.g., 1000Ω), resulting in a lower total impedance for the first antenna branch (to obtain all energy) and a higher total impedance for the second antenna branch. The chip obtains the RSSI value of the first antenna ANT1 in its current state through the receiver and records this parameter.

[0101] The chip then configures the first adjustable resistor R01 to a high resistance value (e.g., 1000Ω) and the second adjustable resistor R02 to a low resistance value (e.g., 10Ω), resulting in a lower total impedance of the second antenna branch (to obtain all energy) and a higher total impedance of the first antenna branch. The chip acquires the RSSI value of the second antenna ANT2 in the current state and records this parameter.

[0102] The chip compares the two RSSI values ​​with preset thresholds and determines the antenna with the better signal quality as the target antenna for this communication. Let's assume the first antenna, ANT1, is determined as the target antenna.

[0103] Based on the target antenna selection result, the chip configures the first adjustable resistor R01 to a first resistance value (low resistance, such as 10Ω) and the second adjustable resistor R02 to a second resistance value (high resistance, such as 1000Ω).

[0104] With this resistance configuration, the first antenna branch, due to the series connection of the low-resistance first adjustable resistor R01, exhibits a low total equivalent impedance at the target operating frequency. Current easily flows into this branch, allowing the first antenna ANT1 to obtain the main transmission energy. The second antenna branch, due to the series connection of the high-resistance second adjustable resistor R02, exhibits a high total equivalent impedance at the target operating frequency. This branch has extremely high impedance, resulting in minimal current flow, effectively functioning as an open circuit.

[0105] Due to the impedance difference between the two branches, the differential transmit signal current output by the near-field communication chip through the first output terminal TX1 and the second output terminal TX2 preferentially flows into the first antenna branch. The current in the second antenna branch is extremely small due to its high impedance and can be ignored.

[0106] As a result, the target antenna, the first antenna ANT1, obtains transmission energy that is close to the total power of the first output terminal TX1 and the second output terminal TX2, while the non-target antenna, the second antenna ANT2, fails to obtain significant energy.

[0107] After identifying the target antenna ANT1, the chip maintains the current resistance values ​​of the two adjustable resistors without switching them, ensuring that ANT1 remains in a state where it receives all transmission energy. This locked state persists until the communication mission is completed. After the mission is finished, the chip can re-enter polling.

[0108] All three parallel schemes described above can achieve the technical effect of the target antenna obtaining all the transmission energy without relying on physical switches or cutting off any physical connections, through impedance regulation. Those skilled in the art can choose the appropriate method to implement according to the actual application scenario (such as chip resources, PCB layout space, cost requirements, etc.).

[0109] It should be understood that the above description using two antennas as an example is merely illustrative, and the technical solution of this application is also applicable to scenarios with three or more antennas. When it is necessary to expand to three antennas, it is only necessary to continue to connect a third antenna branch (including the corresponding compensation circuit and antenna) in parallel on the matching branch. Accordingly, the capacitance value of the adjustable capacitor C7 can be configured to multiple discrete values, each capacitance value corresponding to making one antenna branch present a wide passband / low impedance state (i.e., selected) at the target operating frequency, while other branches present a narrow passband / high impedance state. Similarly, in the internal chip solution, adding a new antenna branch only requires adding a corresponding adjustable submodule.

[0110] The above embodiments are merely exemplary embodiments of this application and are not intended to limit this application. Those skilled in the art can make various modifications or equivalent substitutions to this application within the scope and nature of this application, and such modifications or equivalent substitutions should also be considered to fall within the scope of protection of this application.

Claims

1. An electronic device, comprising: A near-field communication chip, the near-field communication chip having a first output terminal and a second output terminal; Multiple antennas, each of the multiple antennas includes a first end and a second end, the first end of each antenna is connected to the first output end, and the second end of each antenna is connected to the second output end, so that each antenna serves as a sensing loop of the near-field communication chip; The near-field communication chip is configured to select one antenna from the plurality of antennas as the target antenna for communication, and output a first transmission signal in differential form through the first output terminal and a second transmission signal through the second output terminal. The target antenna receives more of the first transmission signal and the second transmission signal than the other antennas in the plurality of antennas, so that the transmission energy of the target antenna relative to the other antennas in the plurality of antennas is closer to the superposition of the transmission energy of the first transmission signal and the second transmission signal.

2. The electronic device according to claim 1, wherein the near-field communication chip is configured to select one antenna from the plurality of antennas as the target antenna for communication, comprising: The other antennas among the plurality of antennas are configured to be in an open-circuit state so that the first transmitted signal and the second transmitted signal flow into the target antenna.

3. The electronic device according to claim 1 or 2, wherein, The near-field communication chip is configured to select one antenna from the plurality of antennas as the target antenna for communication, including: The electronic device is configured to include an adjustable module, which puts the target antenna in a low impedance state and the other antennas in a high impedance state, thereby concentrating the first transmission signal output from the first output terminal and the second transmission signal output from the second output terminal onto the target antenna. The adjustable module is used to adjust the impedance state of each of the plurality of antennas.

4. The electronic device according to claim 3, wherein, The adjustable module belongs to the matching branch. The first end of the matching branch is connected to the first output terminal, the second end of the matching branch is connected to the second output terminal, and the matching branch is connected in parallel with each of the plurality of antennas.

5. The electronic device according to claim 4, wherein, The adjustable module is an adjustable capacitor. By changing the capacitance value of the adjustable capacitor, multiple antennas can present different equivalent impedance states at the target operating frequency of the near-field communication chip. The target operating frequency is the operating frequency of the first transmitted signal and the second transmitted signal.

6. The electronic device according to claim 5, wherein, By configuring the adjustable capacitor to a first capacitance value, the first LCR compensation circuit, the first antenna, and the adjustable capacitor in the first antenna branch are made to form a low input impedance matched state at the target operating frequency. At the same time, the second LCR compensation circuit, the second antenna, and the adjustable capacitor in the second antenna branch are made to form a high input impedance detuned state at the target operating frequency, so that the output current of the near-field communication chip preferentially flows into the first antenna branch, and the second antenna branch is approximately in an open circuit state due to its high input impedance. By configuring the adjustable capacitor to the second capacitance value, the second LCR compensation circuit, the second antenna, and the adjustable capacitor in the second antenna branch are made to form a low input impedance matching state at the target operating frequency, and the first LCR compensation circuit, the first antenna, and the adjustable capacitor in the first antenna branch are made to form a high input impedance detuning state at the target operating frequency. This causes the output current of the near-field communication chip to preferentially flow into the second antenna branch, and the first antenna branch is approximately in an open circuit state due to its high input impedance.

7. The electronic device according to claim 3, wherein, The adjustable module consists of multiple adjustable sub-modules located within the near-field communication chip, and multiple control ports on the near-field communication chip corresponding to the multiple adjustable sub-modules are connected to the multiple antennas via multiple cables.

8. The electronic device according to claim 7, wherein, The plurality of adjustable submodules are connected to the ground of the electronic device via connection points on the near-field communication chip, and the adjustable submodule is an adjustable resistor; By configuring the corresponding adjustable submodules to different resistance values ​​through different control ports, the equivalent impedance of each of the multiple antennas at the target operating frequency of the near-field communication chip is changed. The target operating frequency is the operating frequency of the first transmission signal and the second transmission signal.

9. The electronic device according to claim 8, wherein, The first control port is connected to the first antenna branch via a first cable, and the first adjustable resistor is configured as the controller of the first antenna branch; the second control port is connected to the second antenna branch via a second cable, and the second adjustable resistor is configured as the controller of the second antenna branch. in, By configuring the first adjustable resistor to a first resistance value and the second adjustable resistor to a second resistance value higher than the first resistance value, the near-field communication chip is configured to operate in a first antenna state. In the first antenna state, the first antenna branch is in a low equivalent impedance state at the target operating frequency, and the second antenna branch is in a high equivalent impedance state at the target operating frequency, so that the output current of the near-field communication chip preferentially flows into the first antenna branch. By configuring the first adjustable resistor to the second resistance value and the second adjustable resistor to the first resistance value, the near-field communication chip is configured to operate in the second antenna state. In the second antenna operating state, the second antenna branch is in a low equivalent impedance state at the target operating frequency, and the first antenna branch is in a high equivalent impedance state at the target operating frequency, so that the output current of the near-field communication chip preferentially flows into the second antenna branch.

10. The electronic device according to claim 3, wherein the near-field communication chip further comprises a receiving end, and each of the antennas is used to acquire signal parameters characterizing the strength of the received signal; The near-field communication chip is configured to alternately configure the parameters of the adjustable module in time, so that the multiple antennas are sequentially in a working state that can obtain all the transmitted energy, so as to obtain the signal parameters corresponding to each antenna respectively; The near-field communication chip determines the target antenna from the plurality of antennas based on the signal parameters and preset thresholds. The parameters of the adjustable module and the target antenna are maintained in a working state to obtain all the transmitted energy until the mission is completed.

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