Antenna structure and terminal equipment

Abstract

The invention provides an antenna structure and terminal equipment, and belongs to the technical field of antennas. The antenna structure comprises a first radiation branch knot, a second radiation branch knot, an inductive circuit, a first feed circuit and a second feed circuit, the first feed circuit and the second feed circuit are electrically connected with the first radiation branch knot, and the first radiation branch knot and the second radiation branch knot are electrically connected through the inductive circuit. The first radiation branch knot and the second radiation branch knot are electrically grounded. According to the antenna structure, the first radiation branch knot and the second radiation branch knot are electrically connected through the inductive circuit, so that the effective conductive length of the antenna structure is increased, the antenna structure can meet the radiation requirement of an NFC antenna, integration of the NFC antenna and a conventional antenna is achieved, the NFC antenna is arranged at the position of the conventional antenna, and the antenna structure is more compact. The stacking space of the camera module is avoided, and the implementation difficulty of the NFC antenna is reduced.

Description

Technical Field

[0001] The present application relates to the field of antenna technology, and in particular to an antenna structure and a terminal device. Background Art

[0002] With the development of terminal devices such as smart phones, in addition to basic functions, people have increasingly strong demands for functions such as photography, payment, and access cards. The photography demand requires a larger camera module (including but not limited to sensors, cameras, exterior covers, etc.), while the payment and access card demands support for Near Field Communication (NFC) technology. The implementation of NFC technology depends on NFC antennas.

[0003] However, in the terminal device of the related art, the stacking space of the camera module and the NFC antenna overlaps, and the increase in the volume of the former makes the stacking space of the latter insufficient, which makes the implementation of the NFC antenna more difficult. Summary of the invention

[0004] The present application provides an antenna structure and a terminal device, which can solve the problem of insufficient stacking space for NFC antennas and increased implementation difficulty.

[0005] The technical solution is as follows:

[0006] In one aspect, an antenna structure is provided, the antenna structure comprising: a first radiating branch, a second radiating branch, an inductive circuit, a first feeding circuit, and a second feeding circuit;

[0007] The first feeding circuit and the second feeding circuit are electrically connected to the first radiation branch respectively, and the first radiation branch is electrically connected to the second radiation branch via the inductive circuit;

[0008] The first radiation branch and the second radiation branch are electrically grounded respectively.

[0009] In some embodiments, the antenna structure includes a first operating state and a second operating state;

[0010] In the first working state, the first feeding circuit inputs a first radio frequency signal to the first radiating branch, and the antenna structure operates at 0.7-2.7 GHz;

[0011] In the second working state, the second feeding circuit inputs a second radio frequency signal to the first radiation branch, and the antenna structure operates at 13.56 MHz.

[0012] In some embodiments, the effective conductive length of the first radiation branch between the second feeding circuit and the inductive circuit is L1;

[0013] The effective conductive length of the inductive circuit is L2;

[0014] The effective conductive length between the inductive circuit and the grounding point of the second radiation branch is L3;

[0015] Satisfies the requirement of L1+L2+L3≥40mm.

[0016] In some embodiments, the first feeding circuit includes at least one first capacitive device connected in series, and the total capacitance of the at least one first capacitive device ranges from 90 pF to 110 pF;

[0017] and / or,

[0018] The inductive circuit includes at least one inductive device connected in series, and the total inductance of the at least one inductive device ranges from 58 to 78 nH.

[0019] In some embodiments, the antenna structure further includes a third feeding circuit, and the third feeding circuit is electrically connected to the second radiation branch;

[0020] The antenna structure includes a third working state;

[0021] In the third working state, the third feeding circuit inputs a third radio frequency signal to the second radiation branch, and the antenna structure operates at 1.7-2.7 GHz.

[0022] In some embodiments, the first feeding circuit includes at least one first capacitive device connected in series, and the total capacitance of the at least one first capacitive device ranges from 90 pF to 110 pF;

[0023] and / or,

[0024] The inductive circuit includes at least one inductive device connected in series, and the total inductance of the at least one inductive device ranges from 158 to 178 nH.

[0025] In some embodiments, the first radiation branch node is provided with a first electrical connection point, a second electrical connection point and a third electrical connection point, and the second radiation branch node is provided with a fourth electrical connection point and a fifth electrical connection point;

[0026] The first feeding circuit and the second feeding circuit are electrically connected to one of the first electrical connection point and the second electrical connection point respectively;

[0027] One end of the inductive circuit is electrically connected to the third electrical connection point, a second end of the inductive circuit is electrically connected to the fourth electrical connection point, and the fifth electrical connection point is electrically grounded.

[0028] In some embodiments, the antenna structure further includes a first metal dome, a second metal dome and a circuit board;

[0029] The third electrical connection point is electrically connected to the circuit board through the first metal spring, the fourth electrical connection point is electrically connected to the circuit board through the second metal spring, the inductive circuit is located on the circuit board, and the inductive circuit is electrically connected between the first metal spring and the second metal spring.

[0030] In some embodiments, the antenna structure further includes a first switching circuit, the first feeding circuit is electrically connected to one of the first electrical connection point and the second electrical connection point, and the first switching circuit is electrically connected to the other of the first electrical connection point and the second electrical connection point;

[0031] and / or,

[0032] The antenna structure includes a third feeding circuit and a second switching circuit, and the second radiation branch also includes a sixth electrical connection point;

[0033] The third feeding circuit is electrically connected to one of the fourth electrical connection point and the sixth electrical connection point, and the second switch circuit is electrically connected to the other of the fourth electrical connection point and the sixth electrical connection point.

[0034] On the other hand, a terminal device is provided, the terminal device comprising the antenna structure described in the present application;

[0035] At least a portion of the antenna structure is located at the bottom of the device body.

[0036] The beneficial effects of the technical solution provided by this application include at least:

[0037] The antenna structure of the present application utilizes an inductive circuit to electrically connect the first radiation branch and the second radiation branch, thereby increasing the effective conductive length of the antenna structure, so that the antenna structure can meet the radiation requirements of the NFC antenna, realize the integration of the NFC antenna and the conventional antenna, and arrange the NFC antenna at the position of the conventional antenna, avoiding the stacking space of the camera module, thereby reducing the difficulty of implementing the NFC antenna. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0039] Figure 1is a structural schematic diagram of the antenna structure provided in Embodiment 1 of the present application;

[0040] Figure 2 is a schematic diagram of the structure of the inductive circuit provided in the embodiment of the present application;

[0041] Figure 3 is a structural schematic diagram of the antenna structure provided in Embodiment 2 of the present application;

[0042] Figure 4 is a schematic diagram of the structure of a terminal device provided in an embodiment of the present application;

[0043] Figure 5 is a schematic diagram of the structure of a terminal device provided by another embodiment of the present application;

[0044] Figure 6 is a frequency response curve of the inductive circuit in the antenna structure of the first embodiment of the present application;

[0045] Figure 7 It is a frequency response curve of the inductive circuit in the antenna structure of the second embodiment of the present application.

[0046] The reference numerals in the figures represent respectively:

[0047] 100. antenna structure; 200. device body;

[0048] 1. first radiation branch; 101. first electrical connection point; 102. second electrical connection point; 103. third electrical connection point;

[0049] 2. second radiating branch; 201. fourth electrical connection point; 202. fifth electrical connection point; 203. sixth electrical connection point;

[0050] 3. Inductive circuit; 301. Inductive device; 3011. First inductor; 3012. Second inductor;

[0051] 4. First feeding circuit; 401. First capacitive device; 402. Second capacitive device;

[0052] 5. A second feeding circuit;

[0053] 6. The third feeding circuit;

[0054] 7. The first metal dome;

[0055] 8. Second metal dome;

[0056] 9. Circuit board;

[0057] 10. The first switching circuit. DETAILED DESCRIPTION

[0058] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0059] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate directions or positional relationships based on the attached Figure 1 The orientation or positional relationship shown is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0060] It should be understood that in the present application, "electrical connection" and "electrical connection" can be understood as physical contact and electrical conduction between components; it can also be understood as a form of connection between different components in the circuit structure through physical lines such as printed circuit board (PCB) copper foil or wires that can transmit electrical signals. "Communication connection" can refer to electrical signal transmission, including wireless communication connection and wired communication connection. Wireless communication connection does not require a physical medium and does not belong to a connection relationship that limits the product structure. "Connection" and "connected" can both refer to a mechanical connection relationship or a physical connection relationship, that is, A is connected to B or A is connected to B, which can mean that there is a fastening component (such as screws, bolts, rivets, etc.) between A and B, or A and B are in contact with each other and A and B are difficult to separate.

[0061] Unless otherwise defined, all technical terms used in the embodiments of the present application have the same meanings as commonly understood by those of ordinary skill in the art.

[0062] The technical solution provided in this application is applicable to electronic devices that adopt one or more of the following communication technologies: Bluetooth (Blue Tooth, BT) communication technology, Global Positioning System (Global Positioning System, GPS) communication technology, Wireless Fidelity (Wireless Fidelity, WiFi) communication technology, Global System For mobile communications (Global System For mobile Communications, GSM) communication technology, Wideband Code Division Multiple Access (Wideband Code Division Multiple Access, WCDMA) communication technology, Long Term Evolution (Long Term Evolution, LTE) communication technology, 5G communication technology and other future communication technologies.

[0063] The electronic device in the embodiment of the present application may be a mobile phone, a tablet computer, a laptop computer, a smart bracelet, a smart watch, a smart helmet, smart glasses, etc. The electronic device may also be a cellular phone, a cordless phone, a Session Initiation Protocol (SIP) phone, a Wireless Local Loop (WLL) station, a Personal Digital Assistant (PDA), a handheld device with wireless communication function, a computing device or other processing device connected to a wireless modem, a vehicle-mounted device, an electronic device in a 5G network, or an electronic device in a future Public Land Mobile Network (PLMN), etc., and the embodiment of the present application does not limit this.

[0064] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below with reference to the accompanying drawings.

[0065] On the one hand, combined with Figure 1 As shown, this embodiment provides an antenna structure 100 , which includes: a first radiation branch 1 , a second radiation branch 2 , an inductive circuit 3 , a first feeding circuit 4 and a second feeding circuit 5 .

[0066] The first feeding circuit 4 and the second feeding circuit 5 are electrically connected to the first radiation branch 1 respectively. The first radiation branch 1 is electrically connected to the second radiation branch 2 via the inductive circuit 3. The first radiation branch 1 and the second radiation branch 2 are electrically grounded respectively.

[0067] The antenna structure 100 of the present application utilizes the inductive circuit 3 to electrically connect the first radiation branch 1 and the second radiation branch 2, thereby increasing the effective conductive length of the antenna structure 100, so that the antenna structure 100 can meet the radiation requirements of the NFC antenna, realize the integration of the NFC antenna and the conventional antenna, arrange the NFC antenna at the position of the conventional antenna, avoid the stacking space of the camera module, and reduce the difficulty of implementing the NFC antenna.

[0068] In some possible implementations, the first radiation branch 1 and the second radiation branch 2 are radiation structures of conventional antennas. Optionally, the types of these conventional antennas include but are not limited to: FPC (Flexible Printed Circuitboard) antenna, LDS (Laser Direct Structuring) antenna, metal middle frame antenna, etc. Alternatively, the functions of these conventional antennas include but are not limited to GPS antenna, WiFi antenna, cellular antenna, etc.

[0069] In some embodiments, the antenna structure 100 includes a first working state and a second working state; in the first working state, the first feeding circuit 4 inputs a first radio frequency signal to the first radiation branch 1, and the antenna structure 100 operates at 0.7-2.7 GHz; in the second working state, the second feeding circuit 5 inputs a second radio frequency signal to the first radiation branch 1, and the antenna structure 100 operates at 13.56 MHz.

[0070] Therefore, the antenna structure 100 of this embodiment can cover the NFC frequency band of 13.56 MHz by switching different radio frequency input sources, so that the conventional antenna can realize the integration of the NFC antenna.

[0071] Meanwhile, the working frequency band of the antenna structure 100 in the first working state is the LMHB band (0.7-2.7 GHz), and the inductive circuit 3 can present a high impedance characteristic in this frequency band, which is equivalent to a short circuit, and can reduce the influence of the inductive circuit 3 on the first working state.

[0072] Combination Figure 2 As shown, in some embodiments, the effective conductive length of the first radiation branch 1 between the second feeding circuit 5 and the inductive circuit 3 is L1; the effective conductive length of the inductive circuit 3 is L2; ​​the effective conductive length between the inductive circuit 3 and the grounding point of the second radiation branch 2 is L3; and L1+L2+L3≥40mm.

[0073] Since the wavelength of the NFC frequency band is relatively large, the effective conductive length required for signal radiation in the NFC frequency band is relatively large. Therefore, the antenna structure 100 of this embodiment uses the inductive circuit 3 to connect the first radiating branch 1 and the second radiating branch 2 in series. The sum of the effective conductive lengths of the first radiating branch 1, the inductive circuit 3 and the second radiating branch 2 is greater than or equal to 40 mm, which can meet the signal radiation requirements of the NFC frequency band.

[0074] In some possible implementations, the value of L1+L2+L3 is, for example, 40 mm, 50 mm, 60 mm, 70 mm, 80 mm, etc. Optionally, L1+L2+L3=47.15 mm.

[0075] Combination Figure 1 As shown, in some embodiments, the first feeding circuit 4 includes at least one first capacitive device 401 connected in series, and the total capacitance of the at least one first capacitive device 401 ranges from 90 pF to 110 pF.

[0076] Since the NFC (13.56MHz) and LB (0.7GHz-1GHz) + MB (1.7GHz-2.2GHz) + HB (2.3GHz-2.7GHz) antennas share the first radiation branch 1 and the second radiation branch 2, in order to avoid mutual influence between the two, corresponding isolation measures are required. Figure 1 In order to avoid the influence of the second working state (NFC frequency band) on the first working state (LMHB frequency band), at least one first capacitor device 401 is connected in series in the first feeding circuit 4 to isolate the influence of the NFC low-frequency signal on the LMHB antenna performance.

[0077] In some possible implementations, the total capacitance of the at least one first capacitive device 401 is, for example, 90 pF, 92 pF, 94 pF, 96 pF, 98 pF, 100 pF, 102 pF, 104 pF, 106 pF, 108 pF, 110 pF, etc. Optionally, the total capacitance of the at least one first capacitive device 401 is 100 pF.

[0078] Exemplarily, the number of the first capacitive devices 401 in the first feeding circuit 4 is, for example, one, two, three, etc. When the number of the first capacitive devices 401 is multiple, the total capacitance is the equivalent capacitance value of all the first capacitive devices 401 .

[0079] Combination Figure 1As shown, in some embodiments, the inductive circuit 3 includes at least one inductive device 301 connected in series, and the total inductance of the at least one inductive device 301 ranges from 58 to 78 nH. When the total inductance in the inductive circuit 3 satisfies the above range, the inductive circuit 3 presents a high impedance characteristic in the LMHB frequency band, which is conducive to reducing the influence of the inductive circuit 3 on the performance of the LMHB antenna.

[0080] In some possible implementations, the total inductance of the at least one inductor 301 is, for example, 58nH, 60nH, 62nH, 64nH, 66nH, 68nH, 70nH, 72nH, 74nH, 76nH, 78nH, etc. Optionally, the total inductance of the at least one inductor 301 is 68nH.

[0081] Exemplarily, the number of the inductor devices 301 of the inductive circuit 3 is, for example, one, two, three, etc. When the number of the inductor devices 301 is multiple, the total inductance is the equivalent inductance value of all the inductor devices 301 .

[0082] Combination Figure 3 As shown, in some embodiments, the antenna structure 100 also includes a third feeding circuit 6, which is electrically connected to the second radiating branch 2; the antenna structure 100 includes a third working state; in the third working state, the third feeding circuit 6 inputs a third RF signal to the second radiating branch 2, and the antenna structure 100 operates at 1.7-2.7 GHz.

[0083] By electrically connecting the third feeding circuit 6 to the second radiation branch 2 , the antenna structure 100 can operate in the third operating state, thereby enriching the operating range of the antenna structure 100 and improving the integration of the antenna structure 100 .

[0084] Combination Figure 3 As shown, in some embodiments, the first feeding circuit 4 includes at least one first capacitive device 401 connected in series, the third feeding circuit 6 includes at least one second capacitive device 402 connected in series, the total capacitance of the at least one first capacitive device 401 is in the range of 90-110 pF, and the total capacitance of the at least one second capacitive device 402 is in the range of 90-110 pF, which is conducive to eliminating the mutual influence between the NFC frequency band and the LMHB frequency band.

[0085] In some possible implementations, the total capacitance of at least one first capacitive device 401 or at least one second capacitive device 402 is, for example, 90 pF, 92 pF, 94 pF, 96 pF, 98 pF, 100 pF, 102 pF, 104 pF, 106 pF, 108 pF, 110 pF, etc. Optionally, the total capacitance of at least one first capacitive device 401 or at least one second capacitive device 402 is 100 pF.

[0086] Combination Figure 3 As shown, in some embodiments, the inductive circuit 3 includes at least one inductive device 301 connected in series, and the total inductance of the at least one inductive device 301 ranges from 158 to 178 nH. When the total inductance in the inductive circuit 3 satisfies the above range, the inductive circuit 3 presents a high impedance characteristic in the LMHB frequency band, which is conducive to reducing the influence of the inductive circuit 3 on the performance of the LMHB antenna.

[0087] In some possible implementations, the total inductance of the at least one inductor device 301 is, for example, 158nH, 160nH, 162nH, 164nH, 166nH, 168nH, 170nH, 172nH, 174nH, 176nH, 178nH, etc. Optionally, the total inductance of the at least one inductor device 301 is 168nH.

[0088] In some other possible implementations, the inductor device 301 includes a first inductor 3011 and a second inductor 3012 , the first inductor 3011 and the second inductor 3012 are connected in series, and the total inductance is the sum of the inductance value of the first inductor 3011 and the inductance value of the second inductor 3012 .

[0089] Combination Figure 1-3 As shown, in some embodiments, the first radiation branch 1 is provided with a first electrical connection point 101 , a second electrical connection point 102 and a third electrical connection point 103 , and the second radiation branch 2 is provided with a fourth electrical connection point 201 and a fifth electrical connection point 202 .

[0090] The first feeding circuit 4 and the second feeding circuit 5 are electrically connected to one of the first electrical connection point 101 and the second electrical connection point 102 respectively; one end of the inductive circuit 3 is electrically connected to the third electrical connection point 103, the second end of the inductive circuit 3 is electrically connected to the fourth electrical connection point 201, and the fifth electrical connection point 202 is electrically grounded.

[0091] Thus, the second feeding circuit 5 corresponding to the NFC frequency band can share an electrical connection point with the first feeding circuit 4 corresponding to the LMHB frequency band, thereby reducing the difficulty of modifying the antenna structure 100. There is no need to add new electrical connection points and routing structures in the antenna structure 100, thereby reducing the difficulty of designing and implementing the antenna structure 100.

[0092] Exemplarily, the first feed circuit 4 is electrically connected to the first electrical connection point 101, and the second feed circuit 5 is electrically connected to the second electrical connection point 102; or, the first feed circuit 4 is electrically connected to the second electrical connection point 102, and the second feed circuit 5 is electrically connected to the first electrical connection point 101; or, the first feed circuit 4 and the second feed circuit 5 are electrically connected to the first electrical connection point 101 at the same time; it is also possible that the first feed circuit 4 and the second feed circuit 5 are electrically connected to the second electrical connection point 102 at the same time.

[0093] Combination Figure 2 As shown, in some embodiments, the antenna structure 100 also includes a first metal spring 7, a second metal spring 8 and a circuit board; the third electrical connection point 103 is electrically connected to the circuit board through the first metal spring 7, and the fourth electrical connection point 201 is electrically connected to the circuit board through the second metal spring 8. The inductive circuit 3 is located on the circuit board, and the inductive circuit 3 is electrically connected between the first metal spring 7 and the second metal spring 8.

[0094] This embodiment makes full use of the structure of the first radiation branch 1 and the second radiation branch 2, and utilizes the first metal spring 7, the second metal spring 8 and the circuit board to realize the routing of the inductive circuit 3. It has a simple structure and requires little change to the antenna structure 100. It is unnecessary to add new electrical connection points and routing structures in the antenna structure 100, thereby reducing the difficulty in designing and implementing the antenna structure 100.

[0095] In some possible implementations, the circuit board 9 includes a printed circuit board (PCB), a flexible printed circuit board (FPC), a rigid-flex board, etc. Exemplarily, the first metal spring 7 and the second metal spring 8 are welded on the circuit board and abut against the first radiation branch 1 and the second radiation branch 2, respectively, so as to realize the electrical connection between the first radiation branch 1 and the second radiation branch 2.

[0096] In another exemplary embodiment, the inductive circuit 3 includes a plated circuit on the surface of the circuit board 9 , and the inductive device 301 is soldered and integrated on the surface of the circuit board 9 .

[0097] Combination Figure 1 , 3As shown, in some embodiments, the antenna structure 100 further includes a first switch circuit 10, the first feed circuit 4 is electrically connected to one of the first electrical connection point 101 and the second electrical connection point 102, and the first switch circuit 10 is electrically connected to the other of the first electrical connection point 101 and the second electrical connection point 102. By using the first feed circuit 4 and the first switch circuit 10, the antenna structure 100 can be frequency tuned within the LMHB frequency band to meet different communication requirements.

[0098] Exemplarily, the first feed circuit 4 is electrically connected to the first electrical connection point 101, and the first switch circuit 10 is electrically connected to the second electrical connection point 102; or, the first feed circuit 4 is electrically connected to the second electrical connection point 102, and the first switch circuit 10 is electrically connected to the first electrical connection point 101.

[0099] Combination Figure 1 , 3 As shown, in some embodiments, the antenna structure 100 includes a third feeding circuit 6 and a second switching circuit 11 , and the second radiation branch 2 further includes a sixth electrical connection point 203 .

[0100] The third feeding circuit 6 is electrically connected to one of the fourth electrical connection point 201 and the sixth electrical connection point 203 , and the second switch circuit 11 is electrically connected to the other of the fourth electrical connection point 201 and the sixth electrical connection point 203 .

[0101] By using the third feeding circuit 6 and the second switch circuit 11 , the antenna structure 100 can be frequency tuned within the LMHB frequency band to meet different communication requirements.

[0102] Exemplarily, the third feed circuit 6 is electrically connected to the fourth electrical connection point 201, and the second switch circuit 11 is electrically connected to the sixth electrical connection point 203; or, the third feed circuit 6 is electrically connected to the sixth electrical connection point 203, and the second switch circuit 11 is electrically connected to the fourth electrical connection point 201.

[0103] Taking the antenna structure 100 provided in the first embodiment of the present application as an example, the first working state is an NFC (13.56MHz) antenna, and the second working state is an LB (0.7GHz-1GHz) + MB (1.7GHz-2.2GHz) + HB (2.3GHz-2.7GHz) antenna. The total inductance of the inductive circuit 3 is 68nH, and the total capacitance of the first capacitive device 401 is 100pF.

[0104] Figure 6 The frequency response curve of the inductive circuit 3 in the first embodiment is shown. Figure 6It can be seen that the inductive circuit 3 exhibits a high impedance characteristic in the MB (1.7 GHz-2.2 GHz) frequency band, which is equivalent to a short circuit, reducing the impact of the inductive connection on the radiation performance in the MB frequency band.

[0105] The following Table 1 is a comparison of the efficiency of the antenna structure 100 of the first embodiment of the present application and the LMHB antenna in the related art. It can be seen from Table 1 that while the antenna structure 100 of the first embodiment of the present application is compatible with NFC, the performance of the LMHB antenna is not significantly reduced. The antenna structure 100 of the first embodiment of the present application can realize the integration of the LMHB antenna and the NFC antenna.

[0106] Table 1 Efficiency comparison between embodiment 1 and related technologies

[0107] Frequency band B28Tx B28R B5Tx B5X B8T B8 Relevant technical efficiency -4.2 -5.9 -6.5 -8.2 -7.8 -8.8 Example 1 Efficiency -4.8 -6.3 -6.8 -8.8 -8.3 -9 Frequency band B3 B1 B40 B41 —— —— Relevant technical efficiency -3 -3.7 -3.3 -2.16 —— —— Example 1 Efficiency -3.2 -3.7 -3.3 -2.2 —— ——

[0108] Taking the antenna structure 100 provided in the second embodiment of the present application as an example, the first working state is an NFC (13.56MHz) antenna, the second working state is an LB (0.7GHz-1GHz) + MB (1.7GHz-2.2GHz) + HB (2.3GHz-2.7GHz) antenna, and the third working state is an MB (1.7GHz-2.2GHz) + HB (2.3GHz-2.7GHz) antenna. The total inductance of the inductive circuit 3 is 168nH (of which the first inductance is 68nH and the second inductance is 100nH), the total capacitance of the first capacitive device 401 is 100pF, and the total capacitance of the second capacitive device 402 is 100pF.

[0109] Figure 7 The frequency response curve of the inductive circuit 3 in the second embodiment is shown. Figure 7 It can be seen that the inductive circuit 3 presents a high impedance characteristic in the LB+HB band, which is equivalent to a short circuit, reducing the influence of the inductive connection on the radiation performance in the LMHB band.

[0110] The following Table 2 is a comparison of the efficiency of the antenna structure 100 of the second embodiment of the present application and the LMHB antenna in the related art. It can be seen from Table 2 that while the antenna structure 100 of the second embodiment of the present application is compatible with NFC, the performance of the LMHB antenna is not significantly reduced. The antenna structure 100 of the second embodiment of the present application can realize the integration of the LMHB antenna and the NFC antenna.

[0111] Table 2 Efficiency comparison between Example 1 and related technologies

[0112]

[0113] On the other hand, combined Figure 4 , 5As shown, this embodiment provides a terminal device, which includes the antenna structure 100 of the present application and a device body 200 ; at least a portion of the antenna structure 100 is located at the bottom of the device body 200 .

[0114] The terminal device of this embodiment adopts the antenna structure of this application and has all the beneficial technical effects of all the embodiments of this invention. The terminal device of this embodiment integrates the NFC antenna on the antenna structure at the bottom of the device body 200, which can avoid the camera module in the back cover area and reduce the design and stacking difficulty of the terminal device.

[0115] It should be noted that the "several" and "at least one" mentioned in this article refer to one or more, and "multiple" and "at least two" refer to two or more. "And / or" describes the association relationship of the associated objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the associated objects before and after are in an "or" relationship.

[0116] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0117] In the description of this specification, the reference terms "certain embodiments", "one embodiment", "some embodiments", "illustrative embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present application.

[0118] The above description is only an embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the principles of the present application shall be included in the protection scope of the present application.

Claims

1. An antenna structure, characterized in that: The antenna structure (100) comprises: a first radiation branch (1), a second radiation branch (2), an inductive circuit (3), a first feeding circuit (4) and a second feeding circuit (5); The first feeding circuit (4) and the second feeding circuit (5) are electrically connected to the first radiation branch (1) respectively, and the first radiation branch (1) and the second radiation branch (2) are electrically connected via the inductive circuit (3); The first radiation branch node (1) and the second radiation branch node (2) are electrically grounded respectively.

2. The antenna structure according to claim 1, characterized in that: The antenna structure (100) comprises a first working state and a second working state; In the first working state, the first feeding circuit (4) inputs a first radio frequency signal to the first radiation branch (1), and the antenna structure (100) operates at 0.7-2.7 GHz; In the second working state, the second feeding circuit (5) inputs a second radio frequency signal to the first radiation branch (1), and the antenna structure (100) operates at 13.56 MHz.

3. The antenna structure according to claim 2, characterized in that: The effective conductive length of the first radiation branch (1) between the second feeding circuit (5) and the inductive circuit (3) is L1; The effective conductive length of the inductive circuit (3) is L2; The effective conductive length between the inductive circuit (3) and the grounding point of the second radiation branch (2) is L3; Satisfies the requirement of L1+L2+L3≥40mm.

4. The antenna structure according to claim 2, characterized in that: The first feeding circuit (4) comprises at least one first capacitive device (401) connected in series, and the total capacitance of the at least one first capacitive device (401) ranges from 90 pF to 110 pF; and / or, The inductive circuit (3) comprises at least one inductive device (301) connected in series, and the total inductance of the at least one inductive device (301) ranges from 58 to 78 nH.

5. The antenna structure according to claim 2, characterized in that: The antenna structure (100) further comprises a third feeding circuit (6), wherein the third feeding circuit (6) is electrically connected to the second radiation branch (2); The antenna structure (100) comprises a third working state; In the third working state, the third feeding circuit (6) inputs a third radio frequency signal to the second radiation branch (2), and the antenna structure (100) operates at 1.7-2.7 GHz.

6. The antenna structure according to claim 5, characterized in that: The first feeding circuit (4) comprises at least one first capacitive device (401) connected in series, and the total capacitance of the at least one first capacitive device (401) ranges from 90 pF to 110 pF; and / or, The inductive circuit (3) comprises at least one inductive device (301) connected in series, and the total inductance of the at least one inductive device (301) ranges from 158 to 178 nH.

7. The antenna structure according to any one of claims 1 to 6, characterized in that: The first radiation branch node (1) is provided with a first electrical connection point (101), a second electrical connection point (102) and a third electrical connection point (103), and the second radiation branch node (2) is provided with a fourth electrical connection point (201) and a fifth electrical connection point (202); The first feeding circuit (4) and the second feeding circuit (5) are electrically connected to one of the first electrical connection point (101) and the second electrical connection point (102), respectively; One end of the inductive circuit (3) is electrically connected to the third electrical connection point (103), a second end of the inductive circuit (3) is electrically connected to the fourth electrical connection point (201), and the fifth electrical connection point (202) is electrically grounded.

8. The antenna structure according to claim 7, characterized in that: The antenna structure (100) further comprises a first metal spring (7), a second metal spring (8) and a circuit board (9); The third electrical connection point (103) is electrically connected to the circuit board (9) via the first metal spring (7), the fourth electrical connection point (201) is electrically connected to the circuit board (9) via the second metal spring (8), the inductive circuit (3) is located on the circuit board (9), and the inductive circuit (3) is electrically connected between the first metal spring (7) and the second metal spring (8).

9. The antenna structure according to claim 7, characterized in that: The antenna structure (100) further comprises a first switch circuit (10), the first feed circuit (4) being electrically connected to one of the first electrical connection point (101) and the second electrical connection point (102), and the first switch circuit (10) being electrically connected to the other of the first electrical connection point (101) and the second electrical connection point (102); and / or, The antenna structure (100) comprises a third feeding circuit (6) and a second switching circuit, and the second radiation branch (2) further comprises a sixth electrical connection point (203); The third feeding circuit (6) is electrically connected to one of the fourth electrical connection point (201) and the sixth electrical connection point (203), and the second switch circuit is electrically connected to the other of the fourth electrical connection point (201) and the sixth electrical connection point (203).

10. A terminal device, characterized in that: The terminal device comprises the antenna structure (100) and a device body (200) according to any one of claims 1 to 9; At least part of the antenna structure (100) is located at the bottom of the device body (200).

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