A near field communication system and electronic device

Abstract

The present disclosure relates to the technical field of near field communication, and discloses a near field communication system and an electronic device. The near field communication system comprises a near field communication control chip, a first low-pass filter, a first impedance matching circuit, a second impedance matching circuit, a first antenna and a second antenna. The first antenna is a near field communication antenna, and the second antenna is any one of a near field communication antenna or a high frequency communication antenna. The first impedance matching circuit is connected between two output ends of the first low-pass filter and the first antenna, and the second impedance matching circuit is connected between one output end of the first low-pass filter and the second antenna. When the second antenna is a near field communication antenna, the second impedance matching circuit is connected with the second antenna. When the second antenna is a high frequency communication antenna, an isolation circuit is further included between the second impedance matching circuit and the second antenna. The electronic device comprises the above near field communication system. The present disclosure can improve the communication range of the electronic device and improve the user experience.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of near field communication, and in particular to a near field communication system and an electronic device. BACKGROUND

[0002] At present, near field communication (NFC) technology is a short-range wireless communication technology, allowing electronic devices to exchange data through non-contact point-to-point data transmission, and the application on mobile terminals has become more and more common. The NFC function mainly relies on the NFC controller chip to realize, and the NFC controller (NFCC) realizes the functions of the radio frequency front end, as well as the functions of contactless technology detection, protocol activation, NFCEE management, routing management, NFC controller interface (NCI), etc. The radio frequency front end is mainly responsible for establishing a near field communication link based on a 13.56 MHz carrier between a remote endpoint. Currently, NFC has three working modes: card emulation mode (card mode), point-to-point mode (P2P mode), and reader / writer mode (card machine mode).

[0003] With the increase of user groups, users have increasing experience of using the NFC system, and electronic devices need to better support the communication between the card mode and the card machine mode. The communication performance of the card machine mode requires the device to transmit a large enough field strength, which means that a good antenna environment is needed. However, with the increasing functions of electronic devices such as mobile phones, a large part of the area on the device needs to be occupied by other modules, such as the increasing space occupied by the camera module, and the NFC antenna layout environment is becoming increasingly poor. In order to ensure that the electronic device has good communication performance in the card machine mode, the existing technology generally sets the NFC antenna position downward to expand the communication range of the NFC antenna, but after moving the NFC antenna downward, the user's card swiping is limited to a certain posture, which is not conducive to the user's card swiping habits, and the user experience is not good. However, if a part of the performance is sacrificed to expand the communication range of the NFC antenna, the use experience of other modules will be reduced.

[0004] Therefore, how to improve the communication range of the electronic device and improve the user experience is a technical problem that needs to be solved by those skilled in the art. SUMMARY

[0005] In order to solve the above technical problems, the present disclosure provides a near field communication system and an electronic device to solve the problem that the electronic device in the prior art cannot improve the near field communication effect and improve the user experience.

[0006] The present disclosure provides a near field communication system, comprising at least a near field communication control chip, a first low pass filter, a first impedance matching circuit, a second impedance matching circuit, a first antenna and a second antenna; wherein the first antenna is a near field communication antenna, and the second antenna is any one of a near field communication antenna or a high frequency communication antenna;

[0007] The near field communication control chip comprises a first sending end and a second sending end, and the first sending end and the second sending end are connected with two input ends of the first low pass filter respectively;

[0008] The first impedance matching circuit is connected between two output ends of the first low pass filter and the first antenna, and the second impedance matching circuit is connected between one output end of the first low pass filter and the second antenna;

[0009] When the second antenna is a near field communication antenna, the second impedance matching circuit is connected with the second antenna;

[0010] When the second antenna is a high frequency communication antenna, the second impedance matching circuit and the second antenna further comprise an isolation circuit.

[0011] Optionally, the second antenna is a high frequency communication antenna;

[0012] The isolation circuit comprises a second low pass filter and a high pass filter, an input end of the second low pass filter is connected with an output end of the second impedance matching circuit, and an output end of the high pass filter and an output end of the second low pass filter are both connected with the second antenna.

[0013] Further optionally, the first impedance matching circuit comprises two first capacitors and two second capacitors, one end of the two first capacitors is connected with two output ends of the first low pass filter respectively, the other end of the two first capacitors is connected with one end of the two second capacitors respectively, and the other end of the two second capacitors is grounded;

[0014] The second impedance matching circuit comprises a third capacitor and a fourth capacitor, one end of the third capacitor is connected with one output end of the first low pass filter, the other end of the third capacitor is connected with one end of the fourth capacitor, and the other end of the fourth capacitor is grounded;

[0015] One end of the isolation circuit is connected between the third capacitor and the fourth capacitor, and the other end of the isolation circuit is connected with the second antenna.

[0016] Optionally, an equivalent impedance formed by the first impedance matching circuit and the first antenna is a first equivalent impedance, and an equivalent impedance formed by the second impedance matching circuit and the second antenna is a second equivalent impedance; wherein the first equivalent impedance is greater than the second equivalent impedance.

[0017] Optionally, the first low pass filter comprises two fifth capacitors and two first inductors;

[0018] One end of the two first inductors is connected to the first sending end and the second sending end respectively, and the other end of the two first inductors is connected to one end of the two fifth capacitors respectively, and the other end of the two fifth capacitors is grounded.

[0019] Optionally, the near field communication control chip further comprises a first receiving end and a second receiving end.

[0020] The first receiving end and the second receiving end are connected to the first antenna through a peripheral receiving circuit.

[0021] The first receiving end and the second receiving end are connected to the second antenna through a peripheral receiving circuit.

[0022] The first receiving end, the second receiving end and the peripheral receiving circuit form a receiving circuit.

[0023] Further optionally, the peripheral receiving circuit comprises two groups of series-connected sixth capacitors and first resistors, the first receiving end is connected to one output end of the first low-pass filter through one group of series-connected sixth capacitors and first resistors, and the second receiving end is connected to the other output end of the first low-pass filter through the other group of series-connected sixth capacitors and first resistors.

[0024] Based on the same inventive concept, the disclosure further provides an electronic device comprising the above-mentioned near field communication system.

[0025] Optionally, the second antenna is a high-frequency communication antenna.

[0026] The electronic device comprises a main body area and a frame area at least partially surrounding the main body area.

[0027] The second antenna is located in the frame area, and the first antenna is located in the main body area.

[0028] Further optionally, the electronic device further comprises a high-frequency communication control chip and a high-frequency impedance matching circuit, and the high-frequency communication control chip is connected to the second antenna through the high-frequency impedance matching circuit.

[0029] The isolation circuit comprises a second low-pass filter and a high-pass filter, an input end of the second low-pass filter is connected to an output end of the second impedance matching circuit, and an input end of the high-pass filter is connected to an output end of the high-frequency impedance matching circuit.

[0030] An output end of the high-pass filter and an output end of the second low-pass filter are both connected to the second antenna.

[0031] Compared with the prior art, the technical scheme provided by the embodiments of the disclosure has the following advantages:

[0032] In the near field communication system of the present disclosure, the near field communication control chip is connected with the first antenna through the first impedance matching circuit, and is connected with the second antenna through the second impedance matching circuit. When the second antenna is a near field communication antenna, it can work together with the first antenna which is also a near field communication antenna to expand the communication range and improve the communication effect. At this time, the second impedance matching circuit and the second antenna can be directly connected without the need to set an isolation circuit, which can save the layout space of the isolation circuit in the device, and is beneficial to increase the layout space of other antenna structures and save costs. When the second antenna is a high-frequency communication antenna, it can reuse the high-frequency communication antenna included in the electronic device using the near field communication system of the present disclosure, and work together with the original first antenna. Even in the card mode, the magnetic field excited by the first antenna and the magnetic field excited by the second antenna of the reused high-frequency communication antenna can be superimposed, and the output power of the near field communication control chip will not be dispersed, which can greatly improve the communication range. When the second antenna is a high-frequency communication antenna, the second impedance matching circuit and the second antenna further include an isolation circuit, which plays a role in isolating the interference between high and low frequencies. When the near field communication system is applied to an electronic device, if the second antenna is a high-frequency communication antenna and the first antenna is a near field communication antenna, the second antenna can be reused without being additionally set, and only the original high-frequency communication antenna in the electronic device is used for near field communication, which can effectively improve the communication range, will not affect the user's card using experience, and can make the user's card using posture more diversified, better improve the user's using satisfaction, and the reuse of the second antenna of the original high-frequency communication antenna of the device for near field communication will not additionally occupy the space of the device. BRIEF DESCRIPTION OF DRAWINGS

[0033] The accompanying drawings, which are incorporated into and form a part of the specification, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the disclosure.

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or the prior art, the accompanying drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, those skilled in the art can obtain other drawings according to these drawings without any creative effort.

[0035] Figure 1 is a structural block diagram of the near field communication system provided by the present disclosure;

[0036] Figure 2 is another structural block diagram of the near field communication system provided by the present disclosure;

[0037] Figure 3 is an electronic device using the near field communication system provided by the present disclosure; Figure 2 is a structural schematic diagram of the electronic device using the near field communication system provided by the present disclosure;

[0038] Figure 4 is adopted Figure 2 Another structural schematic diagram of an electronic device of a near field communication system provided by the present disclosure;

[0039] Figure 5 is adopted Figure 2 Another structural schematic diagram of an electronic device of a near field communication system provided by the present disclosure;

[0040] Figure 6 is Figure 2 Equivalent circuit diagram of the first antenna and the second antenna after resonance in a near field communication system provided by the present disclosure;

[0041] Figure 7 Another structural block diagram of a near field communication system provided by the present disclosure;

[0042] Figure 8 Another structural block diagram of a near field communication system provided by the present disclosure;

[0043] Figure 9 is Figure 8 A circuit model structural schematic diagram of

[0044] Figure 10 is Figure 8 Another circuit model structural schematic diagram of

[0045] Figure 11 is Figure 8 Another circuit model structural schematic diagram of

[0046] Figure 12 A structural schematic diagram of an electronic device provided by the present disclosure;

[0047] Figure 13 is Figure 12 A structural block diagram of an electronic device of DETAILED DESCRIPTION

[0048] In order to enable a person skilled in the art to more clearly understand the above-mentioned purposes, features and advantages of the present disclosure, the schemes of the present disclosure will be further described below. It should be noted that the embodiments of the present disclosure and the features in the embodiments can be combined with each other without conflict.

[0049] In the following description, many specific details are set forth in order to fully understand the present disclosure, but the present disclosure can also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only some of the embodiments of the present disclosure, not all the embodiments.

[0050] Please refer to Figure 1 and Figure 2 , Figure 1is a structural block diagram of a near field communication system provided by an embodiment of the present disclosure, Figure 2 is another structural block diagram of a near field communication system provided by an embodiment of the present disclosure, the near field communication system 000 provided by the embodiment includes at least a near field communication control chip 10, a first low-pass filter 20, a first impedance matching circuit 301, a second impedance matching circuit 302, a first antenna 401 and a second antenna 402; wherein the first antenna 401 is a near field communication antenna, and the second antenna 402 is any one of a near field communication antenna or a high frequency communication antenna;

[0051] The near field communication control chip 10 includes a first sending end TX1 and a second sending end TX2, and the first sending end TX1 and the second sending end TX2 are respectively connected with two input ends of the first low-pass filter 20;

[0052] The first impedance matching circuit 301 is connected between two output ends of the first low-pass filter 20 and the first antenna 401, and the second impedance matching circuit 302 is connected between one output end of the first low-pass filter 20 and the second antenna 402;

[0053] When the second antenna 402 is a near field communication antenna, the second impedance matching circuit 302 and the second antenna 402 are connected;

[0054] When the second antenna 402 is a high frequency communication antenna, the second impedance matching circuit 302 and the second antenna 402 further include an isolation circuit 50 therebetween.

[0055] Specifically, the near field communication system 000 provided by the embodiment can be used in a terminal electronic device with a near field communication function. The near field communication system 000 includes a near field communication control chip 10 and a first low-pass filter 20, and the near field communication control chip 10 can be an NFC control chip. The near field communication control chip 10 includes a first sending end TX1 and a second sending end TX2, and the first sending end TX1 and the second sending end TX2 are respectively connected with two input ends of the first low-pass filter 20. The first low-pass filter 20 is used for low frequency signal shaping and filtering electromagnetic interference, so as to realize that the signals sent and output by the first sending end TX1 and the second sending end TX2 are filtered and output as a sine wave with a frequency of 13.56 MHz. Since the near field communication works at a frequency of 13.56 MHz, the working frequency of the near field communication system 000 can be 13.56 MHz through the first low-pass filter 20, so as to realize wireless identification and communication through inductive coupling and data transmission.

[0056] The near field communication system 000 of the embodiment further comprises a first impedance matching circuit 301, a second impedance matching circuit 302, a first antenna 401 and a second antenna 402. The first antenna 401 is a near field communication antenna. Optionally, the first antenna 401 can be a near field communication antenna included in an electronic device using the near field communication system 000 of the embodiment. The second antenna 402 is either a near field communication antenna or a high frequency communication antenna. Optionally, when the second antenna 402 is a near field communication antenna, the second antenna 402 can be a near field communication antenna additionally added in an electronic device using the near field communication system 000 of the embodiment, or when the second antenna 402 is a high frequency communication antenna, the second antenna 402 can reuse a high frequency communication antenna included in an electronic device using the near field communication system 000 of the embodiment, such as any one of a cellular antenna, a global positioning system antenna, a wireless system antenna, and a Bluetooth system antenna included in a general electronic communication device, which can be reused as the second antenna 402 to enhance the near field communication function.

[0057] The near field communication control chip 10 of the embodiment is connected with the first antenna 401 through the first impedance matching circuit 301, and is also connected with the second antenna 402 through the second impedance matching circuit 302. When the second antenna 402 is a near field communication antenna, the second antenna 402 can jointly act with the first antenna 401 which is also a near field communication antenna to expand the communication range. When the first antenna 401 and the second antenna 402 are both near field communication antennas, both of them can radiate magnetic field to the outside to expand the communication range and improve the communication effect, because they are both metal good conductors. When the second antenna 402 is a near field communication antenna, the second impedance matching circuit 302 and the second antenna 402 can be directly connected, i.e. without the need of setting an isolation circuit, which can save the layout space of the isolation circuit in the device, and is beneficial to increase the layout space of other antenna structures, save the cost, and improve the communication effect.

[0058] The near field communication control chip 10 of the embodiment is connected with the first antenna 401 through the first impedance matching circuit 301, and is also connected with the second antenna 402 through the second impedance matching circuit 302. If the second antenna 402 is a high frequency communication antenna, the high frequency communication antenna included in the electronic device using the near field communication system 000 of the embodiment can be reused, and the first antenna 401 included in the electronic device can work together to expand the near field communication range. Even if used in the card mode, the magnetic field excited by the first antenna 401 can be superimposed with the magnetic field excited by the reused high frequency communication antenna, and the output power of the near field communication control chip 10 will not be dispersed, so that the communication range can be greatly improved and the user experience can be improved. In addition, when the second antenna 402 is a high frequency communication antenna, the second impedance matching circuit 302 and the second antenna 402 further include an isolation circuit 50. Since the working frequency of the high frequency communication antenna such as a cellular antenna, a global positioning system antenna, a wireless system antenna, and a Bluetooth system antenna is in the order of several hundred MHz or several GHz, and the working frequency of the near field communication antenna is generally 13.56 MHz, if the second antenna 402 is a high frequency communication antenna, the isolation circuit 50 can be arranged between the second impedance matching circuit 302 and the second antenna 402, and the isolation circuit 50 can isolate the interference between high frequency and low frequency.

[0059] In the near field communication system 000 of the embodiment, the first impedance matching circuit 301 and the second impedance matching circuit 302 are both used to adjust the transmission load and the resonance frequency. The near field communication control chip 10 simultaneously outputs a differential equal-amplitude square wave signal through the first sending end TX1 and the second sending end TX2, and then converts the differential equal-amplitude square wave signal into a differential equal-amplitude sine wave signal through the first low-pass filter, and then transmits the differential equal-amplitude sine wave signal to the first antenna 401 through the first impedance matching circuit 301, so that the first antenna 401 generates an induced magnetic field to realize radio frequency signal transmission. Optionally, the near field communication system 000 can also include a receiving circuit. The radio frequency signal received by the first antenna 401 is transmitted to the receiving end of the near field communication control chip 10 through the first impedance matching circuit 301 and the receiving circuit, and is demodulated by the near field communication control chip 10. Similarly, the radio frequency signal emitted by the near field communication control chip 10 through the first sending end TX1 and the second sending end TX2 is transmitted to the second antenna 402 through the first low-pass filter and the second impedance matching circuit 302, so that the second antenna 402 generates an induced magnetic field to realize radio frequency signal transmission. The radio frequency signal received by the second antenna 402 is transmitted to the receiving end of the near field communication control chip 10 through the second impedance matching circuit 302 and the receiving circuit, and is demodulated by the near field communication control chip 10.

[0060] Optionally, in this embodiment, the first impedance matching circuit 301 and the second impedance matching circuit 302 can be appropriately adjusted so that the radio frequency signal output by the near-field communication control chip 10 is allocated more than 80% of its power for main communication after passing through the first impedance matching circuit 301, while the remaining power is allocated through the second impedance matching circuit 302 for auxiliary communication.

[0061] When the near-field communication system 000 of this embodiment is applied to an electronic device, if both the second antenna 402 and the first antenna 401 are near-field communication antennas, then by adding another near-field communication antenna in the electronic device to work in conjunction with the existing first antenna 401, the communication range can be effectively improved and the communication effect can be guaranteed. If the second antenna 402 is a high-frequency communication antenna and the first antenna 401 is a near-field communication antenna, then the second antenna 402 does not need to be added separately. It is only necessary to reuse any of the existing high-frequency communication antennas in the electronic device, such as cellular antennas, GPS antennas, wireless system antennas, or Bluetooth antennas, to effectively improve the communication range and guarantee the communication effect. This is beneficial for effectively expanding the near-field communication range and will not occupy additional space in the device.

[0062] In general electronic devices, high-frequency communication antennas are placed on the frame of the device, while near-field communication antennas are placed in the upper half or middle area of ​​the device. Therefore, in order to ensure good communication performance of electronic devices, the position of the near-field communication antenna is usually moved down to expand its communication range. However, after moving the near-field communication antenna down, the user's card swiping posture is more limited to a certain position, which is not conducive to the user's card swiping habits and results in a poor user experience. However, if some performance of the electronic device is sacrificed (such as reducing the space of the camera module and sacrificing camera performance) to expand the communication range of the near-field communication antenna, the user experience of other modules will be reduced.

[0063] In this embodiment, the high-frequency communication antenna (i.e., the second antenna 402) included in the electronic device itself is connected to one output terminal of the first low-pass filter 20 through a second impedance matching circuit 302. By multiplexing the high-frequency communication antenna included in the electronic device itself as the second antenna 402, the placement of the first antenna 401 can be diversified. For example... Figures 3-5 As shown, Figure 3 Is adopted Figure 2 A schematic diagram of the structure of an electronic device in a near-field communication system is provided. Figure 4 Is adopted Figure 2 Another schematic diagram of the electronic device of the provided near-field communication system. Figure 5 Is adopted Figure 2 Another structural diagram of the electronic device provided for the near-field communication system shows that the first antenna 401 can be superimposed on other modules 001 (such as the camera module typically included in electronic devices), as shown below.Figure 3 or the setting position of the first antenna 401 and the setting position of the other module 001 can also be arranged separately in the upper half region of the electronic device, as shown in Figure 4 As shown, even if the setting space of the first antenna 401 is reduced to ensure that the space of the other module 001 is large enough, the communication range will not be reduced because of the second antenna 402; or the setting position of the first antenna 401 can be lowered to the lower half region of the electronic device. Since the second antenna 402 of the embodiment multiplexes any one of the cellular antenna, the global positioning system antenna, the wireless system antenna, and the Bluetooth system antenna originally in the electronic device, that is, the second antenna 402 multiplexes the high-frequency communication antenna included in the electronic device itself, the high-frequency communication antenna is generally arranged at the top frame of the electronic device, so even if the setting position of the first antenna 401 is lowered or the setting space is reduced, it will not affect the user's usage habit, and the user can ensure the near field communication effect of the first antenna 401 or the second antenna 402 in any posture.

[0064] Therefore, the Figure 2 The design scheme that the second antenna 402 multiplexes the high-frequency communication antenna included in the electronic device itself and the near field communication control chip 10 to generate communication can greatly improve the communication range by multiplexing other high-frequency communication antennas through the second antenna 402 without sacrificing the communication performance, and improve the user experience. Even if the first antenna 401 is lowered or the setting space is reduced, the second antenna 402 can also expand the card area to ensure the communication performance in the card mode, improve the near field communication success rate, meet the higher communication performance requirements of the terminal device, not only will not affect the user's card use experience, but also can make the user's card posture more diversified, and better improve the user's use satisfaction.

[0065] Optionally, in the near field communication system 000 of the embodiment, when the second antenna 402 is a high-frequency communication antenna and multiplexes the high-frequency communication antenna included in the electronic device itself and the near field communication control chip 10 to generate communication, the second antenna 402 can only be used as a near field communication antenna when the electronic device needs near field communication, and work together with the first antenna 401 to realize the signal communication effect between the near field communication control chip 10. When the electronic device using the near field communication system 000 of the embodiment does not need to perform near field communication, the second antenna 402 can still be used as a high-frequency communication antenna to realize its own high-frequency communication function.

[0066] Optionally, as Figure 1 and Figure 2As shown, the second impedance matching circuit 302 of the embodiment is connected between an output end of the first low-pass filter 20 and the second antenna 402, and the other end of the second antenna 402 is grounded GND, that is, the second antenna 402 can be a separately arranged near field communication antenna, or can be a high frequency communication antenna originally existing in the electronic device and used as a near field communication antenna, but the second antenna 402 can be arranged as a single-ended grounded antenna and connected with the first transmitting end TX1 of the near field communication control chip 10, and the first antenna 401 is a near field communication system 000 itself and can be a differential antenna structure, so that when the first antenna 401 and the second antenna 402 jointly perform near field communication, the power allocated by the second antenna 402 is low, and the second antenna 402 and the second impedance matching circuit 302 can be more flexible in circuit design and have lower cost.

[0067] In some optional embodiments, please refer to Figure 2 and Figure 6 , Figure 6 is Figure 2 The equivalent circuit diagram of the first antenna and the second antenna after resonance in the near field communication system provided by the embodiment, in the embodiment, the equivalent impedance formed by the first impedance matching circuit 301 of the near field communication system 000 and the first antenna 401 is a first equivalent impedance Z L1 , and the equivalent impedance formed by the second impedance matching circuit 302 and the second antenna 402 is a second equivalent impedance Z L2 ; wherein the first equivalent impedance Z L1 is greater than the second equivalent impedance Z L2 .

[0068] The embodiment explains that in the near field communication system 000, all the power output by the near field communication control chip 10 can be oscillated and dissipated on the equivalent impedance formed by the first impedance matching circuit 301 and the first antenna 401 and the equivalent impedance formed by the second impedance matching circuit 302 and the second antenna 402. To ensure that after the second antenna 402 of the near field communication multiplexes the high frequency communication antenna, the communication performance of the first antenna 401 in the near field communication system 000 does not decrease or decreases to an acceptable range, the ratio of the first equivalent impedance Z L1 and the second equivalent impedance Z L2 can be determined. Generally, the first equivalent impedance Z L1 is greater than the second equivalent impedance Z L2 , for example, the ratio of the first equivalent impedance Z L1 and the second equivalent impedance Z L2 can be adjusted to 3:1 or 4:1, etc. Since the first antenna 401 is originally a near field communication antenna of the near field communication system 000, the setting range is relatively large, and the original main near field communication impedance, that is, the first equivalent impedance Z L1The second antenna 402 can be a little larger, and can assist the near field communication. Thus, the second equivalent impedance Z L2 The second antenna 402 can be a little smaller, so that the inevitable signal interference between the two can be as small as possible, and even if there is interference, it can be minimized. When the near field communication system is in the card mode, the magnetic field excited by the first antenna 401 originally has of the near field communication system 000 and the magnetic field excited by the second antenna 402 of the multiplexed high-frequency communication antenna can be superimposed, and all the power output by the near field communication control chip 10 will not be dispersed; when the near field communication system is in the card mode, the power required during communication is not large, and even if the power is distributed, it will not affect the communication effect.

[0069] In some optional embodiments, please refer to Figure 7 , Figure 7 is another structural block diagram of the near field communication system provided by the embodiment of the present disclosure. In the embodiment, the near field communication system 000 can further include a third impedance matching circuit 303 and a third antenna 403. The third antenna 403 and the second antenna 402 are high-frequency communication antennas, and the first antenna 401 is a near field communication antenna.

[0070] The near field communication control chip 10 includes a first sending end TX1 and a second sending end TX2. The first sending end TX1 and the second sending end TX2 are respectively connected with two input ends of the first low-pass filter 20.

[0071] The first impedance matching circuit 301 is connected between two output ends of the first low-pass filter 20 and the first antenna 401. The second impedance matching circuit 302 is connected between one output end of the first low-pass filter 20 and the second antenna 402. The third impedance matching circuit 303 is connected between the other output end of the first low-pass filter 20 and the third antenna 403.

[0072] The second impedance matching circuit 302 and the second antenna 402 further include a first isolation circuit 501. The third impedance matching circuit 303 and the third antenna 403 further include a second isolation circuit 502.

[0073] The embodiment explains that when the second antenna 402 is a high-frequency communication antenna, the second antenna 402 can multiplex a high-frequency communication antenna included in an electronic device using the near field communication system 000 of the embodiment, such as any one of a cellular antenna, a global positioning system antenna, a wireless system antenna, and a Bluetooth system antenna included in a general electronic communication device, which can be multiplexed as the second antenna 402, to enhance the near field communication function. Moreover, not only one high-frequency communication antenna included in the electronic device can be multiplexed, but also other high-frequency communication antennas can be multiplexed as the near field communication at the same time. For example, Figure 7As shown, the near field communication system 000 can further include a third impedance matching circuit 303 and a third antenna 403, the second antenna 402 is one of a cellular antenna, a global positioning system antenna, a wireless system antenna, a Bluetooth system antenna included in the electronic communication device itself, the third antenna 403 is another one of the cellular antenna, the global positioning system antenna, the wireless system antenna, the Bluetooth system antenna included in the electronic communication device itself, the first antenna 401 is a near field communication antenna, the three NFC antennas (the first antenna 401, the second antenna 402, and the third antenna 403) can work at the same time, which is beneficial to further improve the communication range and improve the near field communication effect.

[0074] It can be understood that, in the embodiment, the impedance distribution of the three NFC antennas can be configured with different powers according to actual scenes in specific implementation, which is not limited in the embodiment. Generally, the first antenna 401 is the main communication antenna, the second antenna 402 is the auxiliary communication antenna, and the third antenna 403 is the supplementary communication antenna of the second antenna 402. For example, the third antenna 403 can only have a card mode communication function, which is beneficial to improve the communication range in the card mode and ensure the communication effect of the near field communication system 000 in different modes.

[0075] In some optional embodiments, please refer to Figure 2 and Figure 8 , Figure 8 is another structure block diagram of the near field communication system provided by the embodiment of the present disclosure. In the embodiment, the second antenna 402 is a high-frequency communication antenna, that is, the second antenna 402 is used for multiplexing the high-frequency communication antenna included in the electronic device for near field communication.

[0076] When the second antenna 402 is a high-frequency communication antenna, the isolation circuit 50 is included between the second impedance matching circuit 302 and the second antenna 402. The isolation circuit 50 includes a second low-pass filter 50L and a high-pass filter 50H. The input end of the second low-pass filter 50L is connected with the output end of the second impedance matching circuit 302. The output end of the high-pass filter 50H and the output end of the second low-pass filter 50L are both connected with the second antenna 402.

[0077] Optionally, when the near field communication system of the embodiment is applied to the electronic device, the input end of the high-pass filter 50H can be connected with a high-frequency impedance matching circuit (not shown in the figure) in the electronic device. For details, please refer to the subsequent embodiments, which are not described herein.

[0078] The embodiment explains that the isolation circuit 50 includes the second low-pass filter 50L and the high-pass filter 50H, that is, the isolation circuit 50 can include a combiner composed of the second low-pass filter 50L and the high-pass filter 50H, the second low-pass filter 50L allows low-frequency signals to pass and attenuates high-frequency signals, and the high-pass filter 50H allows high-frequency signals to pass and attenuates low-frequency signals. The combination of the second low-pass filter 50L and the high-pass filter 50H together forms a combiner, which can realize the separation of low-frequency signals and high-frequency signals. When the electronic device needs near field communication, the second antenna 402 is used as a near field communication antenna and cooperates with the first antenna 401 to realize signal communication effect with the near field communication control chip 10. At this time, the isolation circuit 50 can avoid the influence of high-frequency signals on low-frequency signal transmission during near field communication when the near field communication system is working. When the electronic device does not need near field communication, the second antenna 402 is still used as a high-frequency communication antenna. At this time, the isolation circuit 50 can avoid the influence of low-frequency signals on high-frequency signal transmission during high-frequency communication of the electronic device.

[0079] In some optional embodiments, please refer to Figure 2 and Figure 9 , Figure 9 is Figure 8 a circuit model structure diagram. In the embodiment, the second antenna 402 is used as a high-frequency communication antenna, that is, the second antenna 402 is used for multiplexing the high-frequency communication antenna included in the electronic device for near field communication in the embodiment. In the embodiment, the first low-pass filter 20 includes two fifth capacitors C0 and two first inductors L0.

[0080] One end of the two first inductors L0 is respectively connected to the first sending end TX1 and the second sending end TX2, and the other end of the two first inductors L0 is respectively connected to one end of the two fifth capacitors C0. The other end of the two fifth capacitors C0 is connected to the ground GND1.

[0081] The first low-pass filter 20 is an EMC filter circuit formed by the two fifth capacitors C0 and the two first inductors L0. The first low-pass filter 20 is used for filtering the signals output by the first sending end TX1 and the second sending end TX2 to obtain a filtered signal. The filtered signal is, for example, a fundamental wave signal obtained by eliminating harmonic signals in the transmitted signal after filtering. The signal output by the first sending end TX1 and the second sending end TX2 in the embodiment can output a sine wave with a frequency of 13.56 MHz after filtering by the first low-pass filter 20.

[0082] In the embodiment, the first impedance matching circuit 301 includes two first capacitors C11 and two second capacitors C21, one end of the two first capacitors C11 is connected with two output ends of the first low-pass filter 20 respectively, for example, one end of the two first capacitors C11 is connected between a fifth capacitor C0 and a first inductor L0 included in the first low-pass filter 20 respectively, the other end of the two first capacitors C11 is connected with one end of the two second capacitors C21 respectively, the other end of the two second capacitors C21 is grounded GND1;

[0083] The second impedance matching circuit 302 includes a third capacitor C12 and a fourth capacitor C22, one end of the third capacitor C12 is connected with one output end of the first low-pass filter 20, for example, one end of the third capacitor C12 is connected between a fifth capacitor C0 and a first inductor L0 included in the first low-pass filter 20, the other end of the third capacitor C12 is connected with one end of the fourth capacitor C22, the other end of the fourth capacitor C22 is grounded GND2 (it can be understood that the ground end at this time can be a different grounding position from the ground end connected with the first impedance matching circuit 301, therefore, the ground end is marked as GND2 here);

[0084] One end of the isolation circuit 50 is connected between the third capacitor C12 and the fourth capacitor C22, the other end of the isolation circuit 50 is connected with the second antenna 402, for example, one end of the second low-pass filter 50L included in the isolation circuit 50 is connected between the third capacitor C12 and the fourth capacitor C22, the other end of the second low-pass filter 50L and the high-pass filter 50H are connected with the second antenna 402.

[0085] The embodiment explains that the structure of the first impedance matching circuit 301 can include two first capacitors C11 and two second capacitors C21, one end of the two first capacitors C11 is connected between a fifth capacitor C0 and a first inductor L0 included in the first low-pass filter 20 respectively, the other end of the two first capacitors C11 is connected with one end of the two second capacitors C21 respectively, the other end of the two second capacitors C21 is grounded GND1; the first impedance matching circuit 301 is used for receiving a filtered signal output by the first low-pass filter 20 and outputting a first excitation signal to the first antenna 401, the first excitation signal is used for driving the first antenna 401 to generate a magnetic field. One first capacitor C11 in the first impedance matching circuit 301 is mainly used for realizing impedance matching of one end of the first antenna 401 to the first transmitting end TX1, realizing optimal transmission efficiency, and the other first capacitor C11 is mainly used for realizing impedance matching of the other end of the first antenna 401 to the second transmitting end TX2, realizing optimal transmission efficiency; the two second capacitors C21 in the first impedance matching circuit 301 are mainly used for making the resonant frequency of the first antenna 401 at 13.56 MHz.

[0086] The second impedance matching circuit 302 of the embodiment comprises a third capacitor C12 and a fourth capacitor C22, one end of the third capacitor C12 is connected between a fifth capacitor C0 and a first inductor L0 comprised in the first low pass filter 20, the other end of the third capacitor C12 is connected with one end of the fourth capacitor C22, the other end of the fourth capacitor C22 is connected with the ground GND2; the second impedance matching circuit 302 is used for receiving the filtered signal output by the first low pass filter 20 and outputting a second excitation signal to the second antenna 402, the second excitation signal is used for driving the second antenna 402 to generate a magnetic field. The third capacitor C12 in the second impedance matching circuit 302 is mainly used for realizing impedance matching between one end of the second antenna 402 and the first sending end TX1, realizing optimal transmission efficiency, and the fourth capacitor C22 is mainly used for making the resonant frequency of the second antenna 402 when used as a near field communication be 13.56 MHz.

[0087] It can be understood that, in the first impedance matching circuit 301 of the embodiment, a first node N1 is comprised between a first capacitor C11 and a second capacitor C21, and a second node N2 is comprised between another first capacitor C11 and another second capacitor C21; one end of the first antenna 401 is connected with the first node N1, and the other end of the first antenna 401 is connected with the second node N2; in the second impedance matching circuit 302, a third node N3 is comprised between the third capacitor C12 and a fourth capacitor C22, one end of the isolation circuit 50 is connected with the third node N3, the other end of the isolation circuit 50 is connected with the second antenna 402, and the other end of the second antenna 402 is connected with the ground GND2, thereby realizing the connection between the first impedance matching circuit 301 and the first antenna 401 and realizing the connection between the second impedance matching circuit 302 and the second antenna 402. Since the first antenna 401 is a differential antenna and the second antenna 402 is a single-ended ground antenna in the embodiment, the circuit structure of the first impedance matching circuit 301 is different from the circuit structure of the second impedance matching circuit 302.

[0088] It can be understood that the specific circuit structure of the second low pass filter 50L and the high pass filter 50H comprised in the isolation circuit 50 of the embodiment is not limited, and in the specific implementation, only the second low pass filter 50L needs to allow low-frequency signals to pass through and attenuate high-frequency signals, and the high pass filter 50H needs to allow high-frequency signals to pass through and attenuate low-frequency signals, and the combiner composed of the second low pass filter 50L and the high pass filter 50H can realize the separation of low-frequency signals and high-frequency signals. Optionally, as shown in Figure 10 Figure 10 Figure 8 Another circuit model structure diagram of LPF and an inductor L LPF , and the high pass filter 50H can be a structure comprising a capacitor C​​HPF and inductance L HPF The structure of the isolation circuit 50 in this embodiment Figure 10 This is only an example, and the structure of the isolation circuit 50 in actual implementation includes but is not limited to this, and can be set according to actual needs.

[0089] In some optional embodiments, please refer to Figure 8 and Figure 11 , Figure 11 is Figure 8 Another circuit model structure diagram of the near field communication control chip 10 in this embodiment, the near field communication control chip 10 further includes a first receiving end RX1 and a second receiving end RX2.

[0090] The first receiving end RX1 and the second receiving end RX2 are connected with the first antenna 401 through a peripheral receiving circuit 60.

[0091] The first receiving end RX1 is connected with the second antenna 402 through the peripheral receiving circuit 60.

[0092] The first receiving end RX1, the second receiving end RX2 and the peripheral receiving circuit 60 form a receiving circuit.

[0093] Optionally, the peripheral receiving circuit 60 includes two groups of the sixth capacitor Cr1 and the first resistor Rr1 in series, the first receiving end RX1 is connected with one output end of the first low-pass filter 20 through one group of the sixth capacitor Cr1 and the first resistor Rr1 in series, the second receiving end RX2 is connected with another output end of the first low-pass filter 20 through another group of the sixth capacitor Cr1 and the first resistor Rr1 in series, wherein the sixth capacitor Cr1 is used for filtering out direct current signals.

[0094] When the near field communication system 000 of the embodiment performs near field communication, the near field communication control chip 10 outputs differential equal-amplitude square wave signals through the first sending end TX1 and the second sending end TX2 at the same time, and then converts the differential equal-amplitude square wave signals into differential equal-amplitude sine wave signals through the first low-pass filter 20, and then transmits the differential equal-amplitude sine wave signals to the first antenna 401 through the first impedance matching circuit 301, so that the first antenna 401 generates an induced magnetic field to realize radio frequency signal transmission. The near field communication system 000 can also include a receiving circuit composed of the first receiving end RX1 and the second receiving end RX2 of the near field communication control chip 10 and the sixth capacitor Cr1 and the first resistor Rr1 in series. The radio frequency signal received by the first antenna 401 is transmitted to the near field communication control chip 10 after passing through the receiving circuit formed by the first impedance matching circuit 301, the peripheral receiving circuit 60, the first receiving end RX1 and the second receiving end RX2, and is demodulated by the near field communication control chip 10. Similarly, the radio frequency signal transmitted by the near field communication control chip 10 through the first sending end TX1 is transmitted to the second antenna 402 after passing through the first low-pass filter 20 and the second impedance matching circuit 302, and the second antenna 402 generates an induced magnetic field to realize radio frequency signal transmission. The radio frequency signal received by the second antenna 402 is transmitted to the near field communication control chip 10 after passing through the receiving circuit formed by the second impedance matching circuit 302, the peripheral receiving circuit 60 and the first receiving end RX1, and is also demodulated by the near field communication control chip 10. No matter whether the radio frequency signal received by the antenna passes through the first antenna 401 or the second antenna 402, the signal enters the near field communication control chip 10 from the same receiving circuit and is then demodulated, thereby facilitating cost saving.

[0095] In some optional embodiments, please refer to Figures 1-11 and Figure 12 , Figure 12 is a structural schematic diagram of an electronic device provided by the embodiment of the present disclosure. The electronic device 111 provided by the embodiment can include the near field communication system 000 in any of the foregoing embodiments. Figure 12The embodiments are described by taking the electronic device 111 as a mobile phone as an example. The electronic device 111 in the embodiments can be a terminal device, a mobile phone, a tablet computer, a notebook computer, a desktop computer, a game device, a vehicle-mounted electronic device, a wearable smart device, or other electronic devices such as an electronic database, a car, and an automatic teller machine. The wearable smart device includes a device with full functions and large size, which can realize complete or partial functions without relying on a smart phone, such as a smart watch or smart glasses, and a device that focuses on a certain type of application function and needs to be used in cooperation with other devices such as a smart phone, such as various smart bracelets and smart jewelry for monitoring physical signs. The electronic device 111 provided in the embodiments of the present disclosure has the beneficial effects of the near field communication system 000 provided in the embodiments of the present disclosure, and specific descriptions can be made with reference to the specific descriptions of the near field communication system 000 in the above embodiments. The embodiments will not be described herein again.

[0096] In some optional embodiments, please continue to refer to Figure 12 In the embodiments, the second antenna 402 is a high-frequency communication antenna.

[0097] The electronic device 111 includes a main body area 111A and a frame area 111B surrounding at least part of the main body area 111A.

[0098] The second antenna 402 is located in the frame area 111B, and the first antenna 401 is located in the main body area 111A.

[0099] In the electronic device 111 of the embodiment, the near field communication system 000 included therein is connected to a high frequency communication antenna, i.e., the second antenna 402, included in the electronic device 111 itself via a second impedance matching circuit 302 at an output end of the first low pass filter 20. By multiplexing the high frequency communication antenna included in the electronic device 111 itself as the second antenna 402, the setting position of the first antenna 401 can be diversified. The setting position of the first antenna 401 can be superimposed with other modules (such as a camera module generally included in the electronic device) included in the electronic device 111; or the setting position of the first antenna 401 and the setting position of the other modules can also be arranged separately in the upper half region of the electronic device. In this case, even if the setting space of the first antenna 401 is reduced in order to ensure that the space of the other modules is large enough, the near field communication range will not be reduced because of the multiplexing of the second antenna 402; or the setting position of the first antenna 401 can also be moved down to the lower half region of the electronic device, i.e., the setting position of the first antenna 401 can be located at any position of the main body region 111A of the electronic device 111. The second antenna 402 can multiplex any one of the cellular antenna, the global positioning system antenna, the wireless system antenna, and the Bluetooth system antenna originally included in the electronic device, i.e., the second antenna 402 multiplexes the high frequency communication antenna included in the electronic device itself. Generally, the high frequency communication antenna is arranged in the frame region 111B of the electronic device, such as Figure 12 the schematic top frame region. Therefore, even if the setting position of the first antenna 401 is moved down in the main body region 111A or the setting space is reduced, it will not affect the user's usage habit, and the user can ensure the near field communication effect of the first antenna 401 or the second antenna 402 in any posture.

[0100] In the design scheme of the embodiment, the second antenna 402 multiplexes the high frequency communication antenna included in the electronic device 111 itself and the near field communication control chip 10. Without sacrificing the communication performance, the communication range can be greatly improved by multiplexing other high frequency communication antennas included in the electronic device 111 itself via the second antenna 402, and the user experience can be improved. Even if the setting position of the first antenna 401 is moved down in the main body region 111A or the setting space is reduced, the card swiping area can be expanded by the second antenna 402, the communication performance in the card swiping mode can be ensured, the near field communication success rate can be improved, the higher communication performance requirement of the terminal device can be met, the user's card swiping experience will not be affected, and the user's card swiping posture can be diversified, and the user's usage satisfaction can be better improved.

[0101] Optionally, in the electronic device 111 of the present embodiment, when the second antenna 402 multiplexes the high-frequency communication antenna included in the electronic device 111 itself and the near-field communication control chip 10 to generate communication, the second antenna 402 can be used as a near-field communication antenna only when the electronic device 111 needs near-field communication, and cooperates with the first antenna 401 to achieve the signal communication effect between the near-field communication control chip 10. When the electronic device 111 does not need to perform near-field communication, the second antenna 402 can still be used as a high-frequency communication antenna to achieve its own high-frequency communication function.

[0102] In some optional embodiments, please refer to Figure 12 and Figure 13 , Figure 13 is Figure 12 a structural block diagram of an electronic device, in the present embodiment, the electronic device 111 further includes a high-frequency communication control chip 70 and a high-frequency impedance matching circuit 80, the high-frequency communication control chip 70 is connected with the second antenna 402 through the high-frequency impedance matching circuit 80;

[0103] The isolation circuit 50 includes a second low-pass filter 50L and a high-pass filter 50H, the input end of the second low-pass filter 50L is connected with the output end of the second impedance matching circuit 302, the input end of the high-pass filter 50H is connected with the output end of the high-frequency impedance matching circuit 80,

[0104] The output end of the high-pass filter 50H and the output end of the second low-pass filter 50L are both connected with the second antenna 402.

[0105] The electronic device 111 of the present embodiment includes a near-field communication system 000, and can further include a high-frequency communication control chip 70 and a high-frequency impedance matching circuit 80 for the use of a high-frequency communication antenna. The input end of the high-pass filter 50H in the near-field communication system 000 can be connected with the high-frequency impedance matching circuit 80 in the electronic device 111, and the high-frequency communication performance of the electronic device 111 can be achieved through the control of the high-frequency communication control chip 70.

[0106] The isolation circuit 50 in the near field communication system 000 comprises a second low pass filter 50L and a high pass filter 50H, that is, the isolation circuit 50 can comprise a combiner composed of the second low pass filter 50L and the high pass filter 50H, the second low pass filter 50L allows low frequency signals to pass and attenuates high frequency signals, while the high pass filter 50H allows high frequency signals to pass and attenuates low frequency signals, the combination of the second low pass filter 50L and the high pass filter 50H forms a combiner, which can realize the separation of low frequency signals and high frequency signals, when the electronic device 111 needs near field communication, the second antenna 402 is used as a near field communication antenna, cooperates with the first antenna 401, and realizes signal communication effect between the near field communication control chip 10, at this time, the isolation circuit 50 can avoid the influence of high frequency signals on low frequency signal transmission when the near field communication system 000 works. When the electronic device 111 does not need near field communication, the second antenna 402 is still used as a high frequency communication antenna, at this time, through the control of the high frequency communication control chip 70 and the adjustment of the high frequency impedance matching circuit 80, the high frequency communication performance of the electronic device 111 is realized, and the isolation circuit 50 can avoid the influence of low frequency signals on high frequency signal transmission during the high frequency communication process of the second antenna 402 of the electronic device 111.

[0107] It can be understood that the embodiment does not repeat the structure and principle of how the high frequency communication control chip 70 and the high frequency impedance matching circuit 80 communicate high frequency signals with the second antenna 402, and the specific understanding can refer to the high frequency communication structure of the electronic device in the related technology.

[0108] It should be noted that in this paper, relationship terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between the entities or operations. Moreover, the term "includes", "contains" or any other variant thereof is intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or device. Without more limitation, the element defined by the statement "including a" does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0109] The foregoing is merely illustrative of the various implementations of the present disclosure and the general principles thereof. Numerous modifications can be made to these illustrations, and equivalents can be substituted therefor, without departing from the scope of the present disclosure. The specific embodiments commensurate with the specific application are intended to be illustrative only and not limiting of the scope of the application as set forth in the following claims.

Claims

1. A near field communication system, characterized in that, At least comprising a near field communication control chip, a first low pass filter, a first impedance matching circuit, a second impedance matching circuit, a first antenna and a second antenna; wherein the first antenna is a near field communication antenna, and the second antenna is a high frequency communication antenna; The near field communication control chip comprises a first sending end and a second sending end, and the first sending end and the second sending end are connected with two input ends of the first low pass filter respectively; two output ends of the first low pass filter are connected with the first impedance matching circuit and the second impedance matching circuit respectively; The first impedance matching circuit is connected between two output ends of the first low pass filter and the first antenna, and the second impedance matching circuit is connected between one output end of the first low pass filter and the second antenna; The second impedance matching circuit and the second antenna further comprise an isolation circuit; An equivalent impedance formed by the first impedance matching circuit and the first antenna is a first equivalent impedance, and an equivalent impedance formed by the second impedance matching circuit and the second antenna is a second equivalent impedance; wherein the first equivalent impedance is greater than the second equivalent impedance; The isolation circuit comprises a combiner composed of a second low pass filter and a high pass filter, an input end of the second low pass filter is connected with an output end of the second impedance matching circuit, and an output end of the high pass filter and an output end of the second low pass filter are both connected with the second antenna; the second low pass filter allows low frequency signals to pass through and attenuates high frequency signals, and the high pass filter allows high frequency signals to pass through and attenuates low frequency signals.

2. The near field communication system according to claim 1, wherein The first impedance matching circuit comprises two first capacitors and two second capacitors, one end of the two first capacitors is connected with two output ends of the first low pass filter respectively, the other end of the two first capacitors is connected with one end of the two second capacitors respectively, and the other end of the two second capacitors is grounded; The second impedance matching circuit comprises a third capacitor and a fourth capacitor, one end of the third capacitor is connected with one output end of the first low pass filter, the other end of the third capacitor is connected with one end of the fourth capacitor, and the other end of the fourth capacitor is grounded; One end of the isolation circuit is connected between the third capacitor and the fourth capacitor, and the other end of the isolation circuit is connected with the second antenna.

3. The near field communication system of claim 1, wherein, The first low pass filter comprises two fifth capacitors and two first inductors; One end of the two first inductors is connected with the first sending end and the second sending end respectively, the other end of the two first inductors is connected with one end of the two fifth capacitors respectively, and the other end of the two fifth capacitors is grounded.

4. The near field communication system of claim 1, wherein, The near field communication control chip further comprises a first receiving end and a second receiving end; The first receiving end and the second receiving end are connected with the first antenna through a peripheral receiving circuit; The first receiving end and the second receiving end are connected with the second antenna through the peripheral receiving circuit; The first receiving end, the second receiving end and the peripheral receiving circuit form a receiving circuit.

5. The near field communication system of claim 4, wherein, The peripheral receiving circuit comprises two groups of series-connected sixth capacitors and first resistors, one output end of the first low-pass filter is connected with the first receiving end through one group of series-connected sixth capacitors and first resistors, and the other output end of the first low-pass filter is connected with the second receiving end through the other group of series-connected sixth capacitors and first resistors.

6. An electronic device, comprising: The near field communication system comprises the near field communication system according to any one of claims 1-5. 7.The electronic device of claim 6, wherein, The electronic device comprises a main body area and a frame area at least partially surrounding the main body area; The second antenna is located in the frame area, and the first antenna is located in the main body area.

8. The electronic device of claim 7, wherein, The electronic device further comprises a high-frequency communication control chip and a high-frequency impedance matching circuit, and the high-frequency communication control chip is connected with the second antenna through the high-frequency impedance matching circuit.

Images