Electronic device

Abstract

The application discloses an electronic device, comprising: an antenna coil, the antenna coil having at least three spaced-apart connection points; an NFC chip, the NFC chip being electrically connected with any two of the connection points; an SAR chip, the SAR chip being electrically connected with any two of the connection points; a switching switch, the antenna coil being connected with the NFC chip through the switching switch; a part of the antenna coil between any two of the connection points constitutes an induction antenna, in the case that the NFC chip is connected with two of the connection points, the antenna coil between the two connection points connected with the NFC chip constitutes a first induction antenna; in the case that the SAR chip is connected with two of the connection points, the antenna coil between the two connection points connected with the SAR chip constitutes a second induction antenna. The antenna connected with the NFC chip and the SAR chip can be combined on the antenna coil, the NFC card reading success rate can be improved, and the detection accuracy of the SAR chip when a human body is close can be improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of electronic equipment, and particularly relates to an electronic equipment. BACKGROUND

[0002] Near Field Communication (NFC) is mainly used in scenarios such as access control cards, traffic cards, attendance cards, identity cards and the like, and is a mature technical configuration on a mobile phone at present. An electronic equipment with a radio frequency transmitting function will emit radio frequency signals and energy when communicating, and the energy emitted by the antenna will cause certain harm to the human body when the human body is close to the radio frequency transmitting antenna of the electronic equipment. Therefore, a Specific Absorption Rate (SAR) standard is formulated, and the electronic equipment needs to rely on a SAR sensor to detect the situation of the human body being close. In the existing electronic equipment, the NFC antenna and the SAR antenna are designed separately, and the NFC antenna and the SAR antenna can only work in a single antenna state and cannot be switched in multiple antenna states according to actual needs, resulting in low NFC card reading success rate and low detection accuracy of the SAR sensor when detecting the human body being close. SUMMARY

[0003] The purpose of the embodiments of the application is to provide an electronic equipment to solve the problem that the NFC antenna and the SAR antenna in the existing electronic equipment cannot be switched in multiple antenna states, resulting in low NFC card reading success rate and low detection accuracy of the SAR sensor when detecting the human body being close.

[0004] The embodiments of the application provide an electronic equipment, which comprises:

[0005] An antenna coil, the antenna coil has at least three spaced-apart connection points;

[0006] An NFC chip, the NFC chip is used to be electrically connected with any two of the connection points;

[0007] A SAR chip, the SAR chip is used to be electrically connected with any two of the connection points;

[0008] A switching switch, the antenna coil is connected with the NFC chip through the switching switch and any two of the at least three connection points;

[0009] A part of the antenna coil between any two of the connection points constitutes an induction antenna, and in the case that the NFC chip is connected with two of the connection points, the antenna coil between the two connection points connected with the NFC chip constitutes a first induction antenna;

[0010] In the case that the SAR chip is in conduction with two of the connection points, the antenna coil located between the two connection points in conduction with the SAR chip constitutes a second induction antenna.

[0011] The electronic device further comprises:

[0012] A matching circuit, one end of the matching circuit being electrically connected with the corresponding connection point, and the other end of the matching circuit being electrically connected with the switch.

[0013] The number of the matching circuits is multiple, and any two of the connection points are electrically connected with the switch through the corresponding matching circuits.

[0014] The electronic device further comprises:

[0015] A control module, configured to control the switch to turn on the NFC chip and any two of the connection points.

[0016] The SAR chip has multiple input channels, and any two of the connection points are electrically connected with the corresponding input channels.

[0017] The electronic device further comprises:

[0018] A third antenna, the third antenna being arranged adjacent to the antenna coil.

[0019] The electronic device further comprises:

[0020] A control module, configured to control the third antenna to reduce the transmission power in the case that the SAR chip detects that the distance between the obstacle and the electronic device is less than or equal to a preset distance.

[0021] The antenna coil is wound with multiple turns, and the ends of the two ends of the antenna coil respectively have the connection points.

[0022] The interval distance between any two adjacent connection points is different.

[0023] The antenna coil located between any two of the connection points constitutes an induction area, and the parameters of at least two of the induction areas are different, the parameters including at least one of the length, diameter, material and shape of the coil.

[0024] In the electronic device of the embodiment of the present application, the antenna coil has at least three spaced-apart connection points, the NFC chip is configured to be electrically connected with any two of the connection points, the SAR chip is configured to be electrically connected with any two of the connection points, the antenna coil is connected with the NFC chip through the switching switch to any two of the at least three connection points, and the part of the antenna coil between any two of the connection points constitutes an induction antenna. In the case that the NFC chip is connected with any two of the connection points, the antenna coil between the two connection points connected with the NFC chip constitutes a first induction antenna. In the case that the SAR chip is connected with any two of the connection points, the antenna coil between the two connection points connected with the SAR chip constitutes a second induction antenna. The antenna connected with the NFC chip and the SAR chip can be combined on the antenna coil, different induction antennas can be formed by connecting different connection points of the antenna coil, and the induction antennas connected with the NFC chip and the SAR chip can be switched among different dynamic states, so that the NFC chip and the SAR chip can be connected with different induction antennas, and the NFC card reading success rate and the detection accuracy of the SAR chip when a human body is close can be improved, and the antenna induction sheet of the SAR chip does not need to be designed separately. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 FIG. 1 is a structural schematic diagram of an electronic device according to an embodiment of the present application;

[0026] Figure 2 FIG. 2 is a schematic diagram of an antenna coil in an electronic device according to an embodiment of the present application;

[0027] Figure 3 FIG. 3 is a connection schematic diagram of an antenna coil according to an embodiment of the present application;

[0028] Figure 4 FIG. 4 is a corresponding curve of different antennas and ADC values;

[0029] Figure 5 FIG. 5 is a schematic diagram of a third antenna and an antenna coil according to an embodiment of the present application.

[0030] REFERENCE NUMERALS

[0031] Antenna coil 10; base body 11;

[0032] NFC chip 20;

[0033] SAR chip 30;

[0034] Switching switch 40;

[0035] Matching circuit 50;

[0036] Third antenna 60;

[0037] The application processor 70. DETAILED DESCRIPTION

[0038] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0039] The terms "first", "second", and the like in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described herein. In addition, "and / or" in the specification and claims indicates at least one of the connected objects, and the character " / ", generally indicates that the front and rear associated objects are in a "or" relationship.

[0040] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application. Figures 1 to 5 The electronic device provided by the embodiments of the present application is described in detail below with reference to specific embodiments and application scenarios.

[0041] As Figures 1 to 3As shown, the electronic device of the embodiment of the application comprises an antenna coil 10, an NFC chip 20, an SAR chip 30 and a switching switch 40. The antenna coil 10 can be a coil formed by winding a conductive wire at least once. The antenna coil 10 has at least three spaced-apart connection points. The NFC chip 20 is electrically connected to any two of the connection points. The SAR chip 30 is electrically connected to any two of the connection points. For example, the antenna coil 10 has three spaced-apart connection points. The NFC chip 20 can be electrically connected to any two of the three connection points. The SAR chip 30 can be electrically connected to any two of the three connection points. The NFC chip 20 can be selectively connected to any two of the three connection points. The SAR chip 30 can be selectively connected to any two of the three connection points. When the NFC chip 20 is connected to two of the three connection points, the SAR chip 30 can not be connected to any of the three connection points. Alternatively, when the SAR chip 30 is connected to two of the three connection points, the NFC chip 20 can not be connected to any of the three connection points. The NFC chip 20 and the SAR chip 30 are not connected to the connection points at the same time, which can reduce the mutual interference between the inductive antennas required by the NFC chip 20 and the SAR chip 30 when working. The NFC chip 20, the SAR chip 30 and the connection points can be connected through connection terminals or connection lines, which is convenient for spatial arrangement and connection. The antenna coil 10 can be arranged on a base body 11. The antenna coil 10 can be wound into multiple turns. The antenna coil 10 can be arranged on the surface of the base body 11.

[0042] The NFC chip is an integrated circuit with a microcontroller unit (MCU) and a radio frequency modem inside. It is mainly used to realize the function of an IC chip for near field communication. The IC chip has NFC communication function and can contain NFC functions such as card reading and card simulation. It can have low power card detection (LPCD) function and can accurately detect the antenna detuning condition after metal equivalent objects such as human body, card and metal are close. The IC chip can have the ability to quantitatively detect the distance of the object close to it.

[0043] Electronic devices with radio frequency transmitting function will emit radio frequency signals and energy when communicating. When the human body is close to the radio frequency transmitting antenna of the electronic device, the energy emitted by the antenna will cause certain harm to the human body, so the electromagnetic wave absorption ratio or specific absorption rate (SAR) standard is established. In order to reduce the harm to the human body, the antenna transmitting power can be appropriately reduced when the electronic device is close to the human body. The human body proximity detection can be realized through a SAR chip. The sensor used for human body proximity detection can be referred to as a SAR chip. The proximity of external objects to the antenna of the SAR chip will cause a change in capacitance, and the change in capacitance can be used to detect whether an object is close. The change in capacitance can be converted into a change in voltage, and the voltage signal can be converted into an analog signal. The human body proximity condition can be detected according to the analog signal. The SAR chip can have a single or multiple ADC detection channel, and one SAR chip can be equipped with one or more sensing antennas.

[0044] As shown in Figure 3 The electronic device can further include an application processor 70, which can be electrically connected with the NFC chip 20 and the SAR chip 30. The application processor 70 can analyze and process data or signals of the NFC chip 20 and the SAR chip 30, and control the NFC chip 20 and the SAR chip 30 through the application processor 70. The application processor 70 can wake up the NFC chip 20. In the case of requiring sensing detection, the application processor 70 can wake up the NFC chip 20 to perform sensing detection through the NFC chip 20. The application processor 70 can be woken up through the NFC chip 20, so that the application processor 70 is in a working state. The application processor 70 and the NFC chip 20 can be electrically connected through an I 2 C (Inter-Integrated Circuit) bus to transmit signals. The application processor 70 and the NFC chip 20 can be connected through a serial peripheral interface (SPI) to stabilize signal transmission. The SAR chip 30 can process signals according to a clock signal input by the application processor 70.

[0045] The antenna coil 10 is connected with the NFC chip 20 through the switching switch 40 to any two connection points of the at least three connection points. As Figure 3As shown, the antenna coil 10 can be connected to the NFC chip 20 through the switch 40 by switching any two of the three connection points. For example, the antenna coil 10 has three spaced-apart connection points, and the antenna coil 10 can be connected to the NFC chip 20 through the switch 40 by switching any two of the three connection points. When the antenna coil 10 is connected to the NFC chip 20 through the switch 40 by switching different two connection points, the inductive antenna formed by the antenna coil between the different two connection points connected to the NFC chip 20 can be different, so that the NFC chip 20 can be inducted and detected under different inductive antennas, and the detection success rate is improved.

[0046] The part of the antenna coil 10 between any two connection points can form an inductive antenna. When the NFC chip 20 is connected to the two connection points, the antenna coil between the two connection points connected to the NFC chip 20 forms a first inductive antenna. The NFC chip 20 can be connected to any two connection points by switching, so that the first inductive antenna can be different. By connecting the NFC chip 20 to different connection points, the NFC chip 20 is connected to different inductive antennas, detection under different inductive antennas is realized, the NFC card reading success rate is improved, and the adaptability of NFC chip 20 card reading failure is reduced.

[0047] When the SAR chip 30 is connected to the two connection points, the antenna coil between the two connection points connected to the SAR chip 30 forms a second inductive antenna. The SAR chip 30 can be connected to any two connection points, and the SAR chip 30 can be detected under different inductive antennas, so that the detection accuracy of the SAR chip 30 when the human body is close is improved. The antenna inductive sheet of the SAR chip does not need to be designed separately. By connecting the SAR chip 30 to different connection points, the SAR chip 30 is connected to different inductive antennas, and detection under different inductive antennas is realized.

[0048] In the electronic device of the embodiment of the present application, the antenna connected to the NFC chip and the SAR chip can be combined on the antenna coil. Different inductive antennas can be formed by connecting different connection points on the antenna coil. The inductive antennas connected to the NFC chip and the SAR chip can be switched between multiple different dynamic states, so that the NFC chip and the SAR chip can be connected to different inductive antennas, inductive and detection are performed through different inductive antennas, the NFC card reading success rate is improved, the detection accuracy of the SAR chip when the human body is close is improved, the antenna inductive sheet of the SAR chip does not need to be designed separately, and the process technology is simple. The inductive antennas corresponding to the NFC chip and the SAR chip are the same antenna coil, and the NFC chip and the SAR chip work in time division mode, so that mutual interference of the NFC chip and the SAR chip during detection is avoided.

[0049] In some embodiments, as shown in Figure 3 The electronic device can further include a matching circuit 50, one end of the matching circuit 50 being electrically connected to the corresponding connection point, and the other end of the matching circuit 50 being electrically connected to the switching switch 40. The impedance of the circuit can be adjusted through the matching circuit 50, and the passive device composition required for NFC detection can be ensured, and the antenna connected with the NFC chip 20 can normally transmit field strength.

[0050] Optionally, the number of matching circuits 50 can be multiple, and any two connection points can be electrically connected to the switching switch 40 through the corresponding matching circuit 50, so that the switching switch 40 can independently adjust the impedance of the circuit when different connection points are turned on.

[0051] In some embodiments, the electronic device can further include a control module, which can be integrated in the application processor 70, and the control module can be used to control the switching switch 40 to turn on the NFC chip 20 and any two connection points. The NFC chip 20 can be turned on with different connection points, so that the NFC chip 20 is connected with different inductive antennas to realize detection under different inductive antennas and improve the success rate of NFC card reading. The control module can control the switching switch 40 to turn on the NFC chip 20 and any two connection points, and according to actual needs, the control module can control the switching switch 40 to turn on the NFC chip 20 and different two connection points to make the NFC chip 20 connected with different inductive antennas.

[0052] Optionally, the SAR chip 30 can have multiple input channels, any two connection points being electrically connected to the corresponding input channels, and the second inductive antenna formed by the antenna coils between any two connection points can be different. The SAR chip 30 can be connected with multiple different second inductive antennas, so that the SAR chip 30 can detect through different second inductive antennas to improve the detection accuracy of the SAR chip when the human body is close.

[0053] In the embodiments of the present application, as shown in Figure 5 The electronic device can further include a third antenna 60, which can be arranged adjacent to the antenna coil 10, and the third antenna 60 can be arranged spaced apart from the antenna coil 10, so that the human body proximity detected by the antenna coil 10 is similar to the case of the third antenna 60 being away from the human body, and the emission power of the third antenna 60 can be controlled according to the human body proximity.

[0054] In some embodiments, the electronic device can further include a control module configured to control the third antenna 60 to reduce the transmission power in a case where the SAR chip 30 detects that the distance between the obstacle and the electronic device is less than or equal to a preset distance. The control module can control the third antenna 60 to reduce the transmission power in a case where the SAR chip 30 detects that the distance between the human body and the electronic device is less than or equal to a preset distance, so as to reduce the harm of the radiation of the third antenna 60 to the human body. The third antenna 60 can be a radio frequency (RF) antenna, and the inductive antenna of the NFC and the third antenna 60 can be arranged as required. The antenna of the NFC can be arranged according to the area where the user is actually easy to read the card, so as to improve the ease of use and convenience of the user. The third antenna 60 can be arranged at a position with good peripheral clearance, so as to improve the antenna performance and transmission efficiency. The antenna coil 10 can be located in the vicinity of the third antenna 60.

[0055] The antenna coil realizes the SAR human body proximity detection. When the human body approaches the third antenna 60, the antenna coil needs to be able to sense. Taking a human hand profile of 12 cm in width and 20 cm in length as an example, the human hand profile area can be as shown in region A. When the edge of the antenna coil and the third antenna 60 are within the single hand profile range, the antenna coil can realize the function of NFC sensing compatible with SAR human body proximity detection, and the power of the third antenna 60 can be reduced as required. Figure 5

[0056] In the embodiments of the present application, the antenna coil 10 can be wound with multiple turns. The ends of the two ends of the antenna coil 10 can respectively have connection points. For example, the antenna coil 10 can be wound with multiple turns. The antenna coil 10 has three connection points distributed at intervals. The ends of the two ends of the antenna coil 10 can respectively have connection points. The interval distance between the adjacent two connection points can be different. The interval distance between the adjacent two connection points can be greater than or equal to one turn. The ends of the two ends of the antenna coil 10 respectively have connection points, which is convenient for connection and can effectively utilize the antenna coil 10 to form an inductive antenna.

[0057] Optionally, the interval distance between any adjacent two connection points is different, so that the part between any adjacent two connection points on the antenna coil is different, so as to form different inductive antennas.

[0058] ​In some embodiments, the antenna coil between any two connection points forms an induction area, and parameters of at least two induction areas are different, and the parameters can include at least one of length, diameter, material, shape of the coil. For example, the antenna coil between two connection points forms an induction area, and the length, diameter, material or shape of at least two induction areas can be different, the length and diameter of at least two induction areas can be different, the length and material of at least two induction areas can be different, and the parameters of the induction area formed by the antenna coil between the two connection points are set to be different, so that the antenna coil between the two connection points forms different induction antennas.

[0059] The antenna coil 10 can serve as an induction antenna for a user to transmit and receive near field communication radio frequency signals and detect the proximity of metal equivalents (human body, etc.). The antenna coil 10 can be composed of a coil on a flexible circuit board, and the antenna coil 10 has certain antenna characteristics, such as inductance L, parasitic capacitance C, internal resistance R, etc., and the parasitic capacitance C characteristic will change after the proximity of external metal equivalents. Any two connection points can be combined to form three different induction antennas. The antenna coil 10 can have three spaced-apart connection points, and the ends of the two ends of the antenna coil 10 can each have a connection point. Two of the three connection points can form a first induction antenna, and due to the three connection points, the three connection points can be a first connection point (ANT1), a second connection point (ANT2), and a third connection point (ANT3), respectively, and the portion between any two connection points can form an induction antenna.

[0060] When NFC is working, the card reading adaptability or success rate can be improved. There are many types of cards on the market, and the design parameters and production processes of various cards may have some deviations. When the NFC card reading device reads the card, a small part of the card reading will fail, resulting in card reading adaptability problems. The antenna coil 10 can be combined into three different induction antennas by connecting different connection points: the connection points ANT1+ANT2 can form antenna 1, the connection points ANT1+ANT3 can form antenna 2, and the connection points ANT2+ANT3 can form antenna 3. When reading the card, different antennas can be dynamically switched for card reading to improve the card reading success rate.

[0061] After the card reading starts, the initial state can be antenna 1 by default, detection is carried out through antenna 1, the NFC chip 20 can send a card reading detection command, when a card is detected, the application processor can be notified that a card is close, and the NFC chip 20 can read the card. If no card is detected, the switching of the antenna is carried out, whether the three antennas of antenna 1, antenna 2 and antenna 3 are switched, if the three antennas are switched, the card reading ends; if the three antennas are not switched, switching to antenna 2 or antenna 3, the NFC chip 20 sends a card reading detection command, when a card is detected, the application processor can be notified that a card is close, and the NFC chip 20 can read the card. For NFC, there are four protocols in the specification, namely ISO14443A protocol, ISO14443B protocol, ISO18902Felica protocol and ISO15693 protocol, and there are also four kinds of cards corresponding to the four protocol categories, each card will only respond to the instruction meeting the requirement of its own protocol, and can periodically send complete card reading commands of four kinds of A, B, F and V protocols, the card reading detection command can include the card reading commands of A, B, F and V protocols, so as to realize the compatible reading support of the four kinds of cards.

[0062] When the SAR chip works, the SAR chip can be connected to different connection points, and different antennas can be combined according to different connection point connection conditions, each different antenna has different electrical characteristics (inductance, capacitance, etc.), and when a metal equivalent object is close, the electrical characteristics of each antenna will change, and the ADC value detected by the SAR chip will also be different. The antenna can be combined into several different antennas, in order to accurately and quantitatively measure the absolute value of the distance of the human body close, the calibration can be carried out on each antenna.

[0063] In the calibration process, antenna 1 can be calibrated first, the SAR chip detects a first ADC value when the simulation human body tool is in the first position, the SAR chip detects a second ADC value when the simulation human body tool is in the second position, the position of the simulation human body tool is moved, and the ADC value detected by the SAR chip when the simulation human body tool is in different positions is detected. Then, antenna 2 and antenna 3 can be calibrated according to the above method, and the ADC value and the distance of the tool of antenna 1, antenna 2 and antenna 3 are fitted respectively, three ADC-distance characteristic curves are obtained, which can be as shown in Figure 4 Antenna 1 corresponds to the ADC-distance characteristic curve a, antenna 2 corresponds to the ADC-distance characteristic curve b, and antenna 3 corresponds to the ADC-distance characteristic curve c.

[0064] In actual operation, when a metallic equivalent object approaches, antennas 1, 2, and 3 undergo different electrical characteristic changes. The SAR chip detects different ADC values, and by substituting them into their respective ADC-distance characteristic curves, the distance values ​​for different antennas can be obtained. The distance values ​​of the three antennas are then averaged to obtain the precise distance to the metallic equivalent object. After receiving the distance value of the metallic equivalent object, the application processor can adjust the transmission power of the RF antennas adjacent to the antenna coils based on the preset distance-RF power relationship. For example, if the SAR chip 30 detects that the distance between the human body and the electronic device is less than or equal to the preset distance, the transmission power of the third antenna 60 can be reduced; if the SAR chip 30 detects that the distance between the human body and the electronic device is greater than the preset distance, the transmission power of the third antenna 60 can be restored to normal power. Because this scheme can obtain a relatively accurate distance value for the metallic equivalent object, a more refined distance-RF power adjustment strategy can be formulated in practical applications. On the one hand, power can be reduced in time when the metallic equivalent object (human body) approaches to avoid harm to the human body; on the other hand, power reduction too early (when approaching) and power restoration too late (when moving away) can be avoided, improving the user experience.

[0065] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. An electronic device, comprising: The application relates to an antenna coil, an NFC chip, a SAR chip, a switching switch and a control module. The antenna coil has at least three spaced-apart connection points. The NFC chip is electrically connected with any two of the connection points. The SAR chip is electrically connected with any two of the connection points. The antenna coil is connected with the NFC chip through the switching switch. The part of the antenna coil between any two of the connection points forms an induction antenna. When the NFC chip is connected with any two of the connection points, the part of the antenna coil between the two connection points forms a first induction antenna. When the SAR chip is connected with any two of the connection points, the part of the antenna coil between the two connection points forms a second induction antenna. When the antenna coil is connected with the NFC chip through the switching switch, the part of the antenna coil between any two of the connection points forms different induction antennas. When the NFC chip is connected with any two of the connection points, the part of the antenna coil between the two connection points forms different first induction antennas.

2. The electronic device of claim 1, wherein, When the SAR chip is connected with any two of the connection points, the part of the antenna coil between the two connection points forms different second induction antennas. The application further comprises a matching circuit.

3. The electronic device of claim 2, wherein, One end of the matching circuit is electrically connected with a corresponding connection point, and the other end of the matching circuit is electrically connected with the switching switch.

4. The electronic device of claim 1, wherein, The number of the matching circuits is plural, and any two of the connection points are electrically connected with the switching switch through corresponding matching circuits. The application further comprises a control module.

5. The electronic device of claim 1, wherein, The control module is used for controlling the switching switch to connect the NFC chip with any two of the connection points.

6. The electronic device of claim 1, wherein, The SAR chip has a plurality of input channels, and any two of the connection points are electrically connected with corresponding input channels. The application further comprises a third antenna.

7. The electronic device of claim 6, wherein, The third antenna is arranged adjacent to the antenna coil. The application further comprises a control module.

8. The electronic device of claim 1, wherein, When the SAR chip detects that the distance between an obstacle and an electronic device is less than or equal to a preset distance, the control module controls the third antenna to reduce the transmission power.

9. The electronic device of claim 1, wherein, The antenna coil has a plurality of turns, and the two ends of the antenna coil have the connection points.

10. The electronic device of claim 1, wherein, The interval distance between any two adjacent connection points is different. The part of the antenna coil between any two of the connection points forms an induction area, and the parameters of at least two induction areas are different, the parameters including at least one of the length, diameter, material and shape of the coil.

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