Antenna structure and antenna working mode switching method

Abstract

The present application discloses an antenna structure and an antenna working mode switching method, wherein the antenna structure comprises: a first antenna arm; a second antenna arm, wherein the distance between the second antenna arm and the first antenna arm is variable; a first tuning device connected to the first antenna arm; and a second tuning device connected to the second antenna arm; when the second antenna arm and the first antenna arm are in a coupled state, if the first tuning device is in a first state and the second tuning device is in a second state, the antenna structure is in a first working mode; if the first tuning device is in the first state and the second tuning device is in a third state, the antenna structure is in a second working mode; wherein the electromagnetic wave specific absorption rate SAR of the antenna structure in the first working mode is less than a first threshold value, and / or the antenna efficiency of the antenna structure in the second working mode is greater than a second threshold value.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to an antenna structure and an antenna working mode switching method. Background Art

[0002] With the development of communication technology, terminals have various forms. In the terminal structure, two antenna structures that can move relatively can be set, such as a main antenna and a parasitic antenna. For example, a main antenna and a parasitic antenna are set on the two main bodies of a folding screen product. When the two antenna structures are close to each other, coupling may cause reverse current.

[0003] For existing terminals, since the distance between the two antenna parts is close, the parasitic antenna may be excited by the main antenna arm, and the excitation current generated by the parasitic antenna may affect the antenna performance or cause a higher specific absorption rate (SAR) of electromagnetic waves. Summary of the invention

[0004] The present application aims to provide an antenna structure and an antenna working mode switching method, so as to solve the problem that the excitation current generated by the parasitic antenna in the existing antenna structure may affect the antenna performance or cause a higher SAR.

[0005] In a first aspect, an embodiment of the present application provides an antenna structure, including:

[0006] a first antenna arm;

[0007] a second antenna arm, wherein the distance between the second antenna arm and the first antenna arm is variable;

[0008] A first tuning device connected to the first antenna;

[0009] a second tuning device connected to the second antenna arm;

[0010] When the second antenna arm is in a coupled state with the first antenna arm, the antenna structure includes a first working mode and a second working mode, and the working mode of the antenna structure is related to the distance between the antenna structure and the human body;

[0011] Wherein, if the first tuning device is in the first state and the second tuning device is in the second state, the antenna structure is in the first working mode; if the first tuning device is in the first state and the second tuning device is in the third state, the antenna structure is in the second working mode;

[0012] The electromagnetic wave specific absorption rate SAR of the antenna structure in the first working mode is less than a first threshold, and / or the antenna efficiency of the antenna structure in the second working mode is greater than a second threshold.

[0013] In a second aspect, an embodiment of the present application provides an electronic device, including the above-mentioned antenna structure; the electronic device also includes:

[0014] A first body and a second body, wherein the first body and the second body are movable relative to each other;

[0015] The first antenna arm is disposed on the first body, and a clearance area is provided between the first antenna arm and the first body;

[0016] The second antenna arm is disposed on the second body, and a clearance area is defined between the second antenna arm and the second body.

[0017] In a third aspect, an embodiment of the present application provides a method for switching an antenna working mode, including:

[0018] When the first antenna arm and the second antenna arm are in a coupled state, detecting the distance between the antenna structure and the human body;

[0019] According to the distance, the antenna structure is placed in a first working mode or a second working mode by adjusting the states of the first tuning device and the second tuning device;

[0020] The SAR of the antenna structure in the first working mode is less than a first threshold, and / or the antenna efficiency of the antenna structure in the second working mode is greater than a second threshold.

[0021] Thus, in the above-mentioned scheme of the present application, the antenna structure includes a first antenna arm and a second antenna arm, the first antenna arm is connected to the first tuning device, and the second antenna arm is connected to the second tuning device. When the first antenna arm and the second antenna arm are in a coupled state, the first tuning device and the second tuning device can be adjusted according to the distance between the antenna structure and the human body, so that the antenna structure operates in a first working mode with a lower SAR, thereby reducing the impact on the human body; or the antenna structure operates in a second working mode with a higher antenna efficiency, thereby improving the antenna efficiency. The antenna structure can meet different working requirements.

[0022] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0024] Figure 1 One of the structural schematic diagrams showing the antenna structure of an embodiment of the present application;

[0025] Figure 2 One of the schematic diagrams showing the dimensions of the first antenna arm and the second antenna arm of the embodiment of the present application;

[0026] Figure 3 A second schematic diagram showing dimensions of the first antenna arm and the second antenna arm of an embodiment of the present application;

[0027] Figure 4 The relationship between the second antenna arms of different lengths and the coupled current according to the embodiment of the present application is shown;

[0028] Figure 5 A third schematic diagram showing dimensions of the first antenna arm and the second antenna arm of an embodiment of the present application;

[0029] Figure 6 A second structural schematic diagram showing the antenna structure of an embodiment of the present application;

[0030] Figure 7 A third structural diagram showing the antenna structure of an embodiment of the present application;

[0031] Figure 8 A fourth structural diagram showing the antenna structure of an embodiment of the present application;

[0032] Fig. 9 A fifth structural diagram showing the antenna structure of an embodiment of the present application;

[0033] Fig.10 A sixth structural diagram showing the antenna structure of an embodiment of the present application;

[0034] Fig.11 A seventh structural diagram showing the antenna structure of an embodiment of the present application;

[0035] Fig.12 One of the S11 schematic diagrams showing the main antenna and the parasitic antenna according to the embodiment of the present application;

[0036] Fig.13 A second S11 schematic diagram showing a main antenna and a parasitic antenna according to an embodiment of the present application;

[0037] Fig.14 S11 schematic diagram 3 showing the main antenna and the parasitic antenna;

[0038] Fig.15 An eighth structural diagram showing the antenna structure of an embodiment of the present application;

[0039] Fig.16A fourth S11 schematic diagram showing a main antenna and a parasitic antenna according to an embodiment of the present application;

[0040] Fig.17 A schematic diagram showing the structure of an electronic device according to an embodiment of the present application;

[0041] Fig.18 A schematic diagram showing the structure of an electronic device in a folded state according to an embodiment of the present application;

[0042] Fig.19 A schematic diagram showing an excitation path of a parasitic antenna according to an embodiment of the present application;

[0043] Fig. 20 A flowchart showing a method for switching antenna working modes according to an embodiment of the present application is shown.

[0044] Explanation of the accompanying drawings: 1. first antenna arm, 2. second antenna arm, 3. first tuning device, 4. second tuning device, 31. first matching network, 32. RF circuit, 33. first tuning network, 34. first switch; 41. second matching network, 42. load, 43. second tuning network, 44. second switch; 21. feed source, 22. first clearance area, 23. second clearance area, 24. first break, 25. second break. DETAILED DESCRIPTION

[0045] Embodiments of the present invention will be described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0046] The features of the terms "first" and "second" in the specification and claims of this application may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0047] In the description of the present invention, 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", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0048] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0049] The antenna structure according to the embodiment of the present invention is described below.

[0050] like Figure 1-Figure 16 As shown, the antenna structure includes:

[0051] First antenna arm 1;

[0052] a second antenna arm 2, wherein the distance between the second antenna arm 2 and the first antenna arm 1 is variable;

[0053] A first tuning device 3 connected to the first antenna arm 1;

[0054] A second tuning device 4 connected to the second antenna arm 2;

[0055] When the second antenna arm 2 is in a coupled state with the first antenna arm 1, the antenna structure includes a first working mode and a second working mode, and the working mode of the antenna structure is related to the distance between the antenna structure and the human body;

[0056] Wherein, if the first tuning device 3 is in the first state and the second tuning device 4 is in the second state, the antenna structure is in the first working mode; if the first tuning device 3 is in the first state and the second tuning device 4 is in the third state, the antenna structure is in the second working mode;

[0057] The electromagnetic wave specific absorption rate SAR of the antenna structure in the first working mode is less than a first threshold, and / or the antenna efficiency of the antenna structure in the second working mode is greater than a second threshold.

[0058] In this embodiment, the first antenna arm 1 and the second antenna arm 2 are two antenna arms arranged on the same electronic device, the first antenna arm 1 can be a main antenna arm, the second antenna arm 2 can be a parasitic antenna arm, and the distance between the second antenna arm 2 and the first antenna arm 1 is variable. For example, the first antenna arm 1 and the second antenna arm 2 are respectively arranged on two foldable parts of the electronic device, and the first antenna arm 1 and the second antenna arm 2 are relatively close to or far away from each other through folding of the electronic device; or, the first antenna arm 1 is arranged on the body of the electronic device, and a retractable and movable structure (such as a camera, an external display screen, etc.) is installed on the electronic device, and the second antenna arm 2 is arranged on the retractable and movable structure, and the first antenna arm 1 and the second antenna arm 2 are relatively close to or far away from each other through the telescopic movement of the structure.

[0059] When the first antenna arm 1 and the second antenna arm 2 are coupled, a reverse current may be generated. Optionally, when the distance between the second antenna arm 2 and the first antenna arm 1 is less than a predetermined threshold, the second antenna arm 2 is coupled with the first antenna arm 1, and the predetermined threshold may be obtained through experiments, for example, by changing the distance between the first antenna arm 1 and the second antenna arm 2 for multiple times, and measuring that the second antenna arm 2 generates a current when the distance is less than the predetermined threshold.

[0060] The first tuning device 3 is connected to the first antenna arm 1, and can adjust the operating frequency of the first antenna arm; the second tuning device 4 is connected to the second antenna arm 2, and can adjust the operating frequency of the second antenna arm 2. When the distance between the second antenna arm 2 and the first antenna arm 1 is relatively close, for example, when the electronic device with a folding screen is in a folded state, the first antenna arm 1 and the second antenna arm 2 are coupled, and the second antenna arm 2 generates a reverse current. The working mode of the antenna structure can be switched by adjusting the first tuning device 3 and the second tuning device 4. The working mode of the antenna structure includes a first working mode (i.e., a low SAR state, which has little impact on the human body) and a second working mode (i.e., a high antenna efficiency state, where the antenna has a high working efficiency). According to the distance between the antenna structure and the human body, when the antenna structure is close to the human body and needs to achieve a low SAR, the first tuning device 3 can be placed in the first state and the second tuning device 4 can be placed in the second state. At this time, the directional current on the second antenna arm 2 is the largest, and the SAR reduction effect is the best. It is the first working mode, which can reduce the impact of the antenna on the human body when the human body is close to the antenna.

[0061] When the antenna structure is far away from the human body and has little impact on the human body and needs to improve the antenna efficiency, the first tuning device 3 can be placed in the first state and the second tuning device 4 can be placed in the third state. At this time, the directional current on the second antenna arm 2 becomes smaller, the SAR reduction effect becomes weaker, and the antenna efficiency of the first antenna arm 1 is improved, which can reduce the influence of the reverse current of the parasitic antenna and improve the antenna efficiency.

[0062] In this embodiment, the state of the first tuning device 3 may refer to the connection state of the device included in the first tuning device 3, for example, the first tuning device 3 includes a switch, and when the switch is connected to a target device, it indicates that the first tuning device 3 is in the first state. The state of the second tuning device 4 may refer to the connection state of the device included in the second tuning device 4, for example, the second tuning device 4 includes a switch, and when the switch is connected to a first target device, it indicates that the second tuning device 4 is in the first state, and when the switch is connected to a second target device, it indicates that the second tuning device 4 is in the third state.

[0063] When the second antenna arm 2 is coupled with the first antenna arm 1, the second antenna arm 2 generates an excitation current, and the working mode of the antenna structure can be adjusted according to the current usage requirements of the electronic device. For example, when the electronic device is close to the human body, in order to avoid a greater impact of the antenna on the human body, the antenna structure can be controlled to switch to the first working mode, that is, the low SAR state; when the electronic device is far away from the human body, a higher antenna working efficiency needs to be ensured, and the antenna structure can be controlled to switch to the second working mode, that is, the high antenna efficiency state.

[0064] In an embodiment of the present application, the antenna structure includes a first antenna arm and a second antenna arm, the first antenna arm is connected to a first tuning device, and the second antenna arm is connected to a second tuning device. When the first antenna arm and the second antenna arm are in a coupled state, the first tuning device and the second tuning device can be adjusted according to the distance between the antenna structure and the human body, so that the antenna structure operates in a first working mode with a lower SAR, thereby reducing the impact on the human body; or the antenna structure operates in a second working mode with a higher antenna efficiency, thereby improving the antenna efficiency. The antenna structure can meet different working requirements.

[0065] Optionally, the first antenna arm 1 and the second antenna arm 2 have the same size; or, the second antenna arm 2 has a smaller size than the first antenna arm 1 .

[0066] In this embodiment, the size of the first antenna arm 1 and the second antenna arm 2 may include antenna lengths, that is, the length of the first antenna arm 1 and the length of the second antenna arm 2 may be the same or different. For example, the first antenna arm 1 is arranged at the B part of the electronic device, and the second antenna arm 2 is arranged at the A part of the electronic device. Figure 2 and Figure 3 As shown, Figure 2 is a schematic diagram showing that the length of the first antenna arm 1 is the same as the length of the second antenna arm 2, Figure 3 This is a schematic diagram showing that the length of the second antenna arm 2 is smaller than the length of the first antenna arm 1 .

[0067] For second antenna arms 2 of different lengths, the amplitude of the coupling current obtained by exciting the second antenna arm 2 is different. Assume that the first antenna arm 1 is the antenna arm of the main antenna, and the second antenna arm 2 is the parasitic antenna arm. Figure 2 and Figure 3 For example, the main antennas of the two groups of models are both monopole antennas, wherein the feed 21 is connected to the first antenna arm 1 (i.e., the antenna arm of the main antenna). Figure 2 The parasitic antenna arm shown has the same size as the antenna arm of the main antenna, so the operating frequency is the same. The parasitic antenna arm can couple to obtain a stronger current in the operating frequency band. The current flow directions of the main antenna and the parasitic antenna arm are shown by arrows. Figure 3 The parasitic antenna arm shown is shorter and has a higher operating frequency than the main antenna. Therefore, the current coupled by the parasitic antenna arm at the main antenna operating frequency is weaker. The relationship between the parasitic antenna arm of different lengths and the coupled current is shown in Figure 1. Figure 4 As shown, L1 represents the length of the antenna arm of the main antenna, and L2 represents the length of the parasitic antenna arm. When the length of the parasitic antenna arm L2 = L1, the coupling current is maximum; when L2 is at 3*L1, the coupling current will also be slightly larger because a higher-order mode appears in the parasitic antenna arm of this length.

[0068] In this embodiment, when the size of the second antenna arm 2 is smaller than that of the first antenna arm 1, the opening between the second antenna arm 2 and the electronic device is symmetrical to the opening between the first antenna arm 1 and the electronic device. Figure 5 As shown, assuming that the first antenna arm 1 is arranged at part B of the electronic device with a folding screen, and the second antenna arm 2 is arranged at part A of the electronic device with a folding screen, the first antenna arm 1 is the antenna arm of the main antenna, and the second antenna arm 2 is the parasitic antenna arm, then the parasitic antenna arm is physically shorter than the antenna arm of the main antenna, which can reduce the intensity of the reverse current coupled to the parasitic antenna arm and enhance the antenna performance of the folding screen in the folded state, and the fractures of part A and part B of the folding screen still satisfy symmetry.

[0069] It should be noted that, in this embodiment, the specific form of the antenna is not limited, and the reverse current intensity is mainly weakened by reducing the physical size of the parasitic antenna.

[0070] The first tuning device 3 and the second tuning device 4 may be composed of a matching network, a tuning network, a radio frequency circuit, a switch and the like, which will be described below through specific embodiments.

[0071] As an optional embodiment, Figure 6 and Figure 7 As shown, the first tuning device 3 includes:

[0072] A first matching network 31 and a radio frequency circuit 32, wherein a first end of the first matching network 31 is connected to the first antenna arm 1, and a second end of the first matching network 31 is connected to the radio frequency circuit 32;

[0073] The second tuning device 4 includes a second matching network 41 and a load 42. The first end of the second matching network 41 is connected to the second antenna arm 2, the second end of the second matching network 41 is connected to the load 42, and the load 42 is grounded.

[0074] Figure 6 The antenna structure is a monopole. Figure 7 The antenna structure of IFA type 1 is shown. Figure 7 As shown, the first antenna arm 1 and the second antenna arm 2 can be grounded respectively. The specific structures of the first matching network 31, the second matching network 41, and the radio frequency circuit 32 are not limited and can be composed of any device capable of achieving tuning, such as capacitors, inductors, switching devices, etc.

[0075] Optionally, the first tuning device 3 further includes: a first tuning network 33 , wherein the first tuning network 33 is connected to the first antenna arm 1 ; the second tuning device 4 further includes: a second tuning network 43 , wherein the second tuning network 43 is connected to the second antenna arm 2 .

[0076] like Figure 8 and Fig. 9 As shown, Figure 8 The antenna structure is a LOOP structure. Fig. 9 It is the antenna structure of IFA type 2. Figure 8 As shown, the first tuning network 33 and the second tuning network 43 are respectively connected to one end of the first antenna arm 1 and the second antenna arm 2 where the lengths are aligned; Fig. 9 As shown, the first tuning network 33 and the second tuning network 43 are respectively connected to the ends of the first antenna arm 1 and the second antenna arm 2 where the lengths are not aligned.

[0077] When the first antenna arm 1 is a main antenna and the second antenna arm 2 is a parasitic antenna, the second tuning device 4 also uses a matching network and a tuning network to adjust the working mode of the passive antenna to be consistent with the working mode of the main antenna, so as to achieve good results in multi-band situations.

[0078] As an optional embodiment, the first tuning device 3 further includes: a first switch 34, the first switch 34 is connected to the M first devices respectively, and when the first switch 34 is connected to different first devices, the operating frequency of the first antenna arm 1 is different;

[0079] The second tuning device 4 further includes: a second switch 44, the second switch 44 is connected to the N second devices respectively, when the second switch 44 is connected to different second devices, the operating frequency of the second antenna arm 2 is different;

[0080] The first switch 34 is connected to the first matching network 31, and the second switch 44 is connected to the second matching network 41; or, the first switch 34 is connected to the first tuning network 33, and the second switch 44 is connected to the second tuning network 43; wherein M is greater than or equal to 1, and N is greater than or equal to 2.

[0081] In this embodiment, a switch may be provided in the first tuning device 3 and / or the second tuning device 4, and the switch may be connected to multiple devices (such as inductors, capacitors, etc.). By switching the connection state between the switch and the device, the antenna structure can work in different working modes.

[0082] Optionally, the first tuning device 3 may include a first matching network 31, a radio frequency circuit 32, a first switch 34, and a plurality of devices connected to the first switch, the first switch 34 is connected to the first matching network 31, and the second tuning device 4 may include a second matching network 41, a load 42, a second switch 44, and a plurality of devices connected to the second switch, the second switch 44 is connected to the second matching network 41. Fig.10 As shown, it is assumed that the first switch 34 connects two devices a and b, and the second switch 44 connects four devices c, d, e, and f.

[0083] Optionally, the first tuning device 3 may include a first matching network 31, a radio frequency circuit 32, a first tuning network 33, a first switch 34, and a plurality of devices connected to the first switch, wherein the first switch 34 is connected to the first tuning network 33; the second tuning device 4 may include a second matching network 41, a load 42, a second tuning network 43, a second switch 44, and a plurality of devices connected to the second switch, wherein the second switch 44 is connected to the second tuning network 43. Fig.11 As shown, it is assumed that the first switch 34 connects two devices a and b, and the second switch 44 connects four devices c, d, e, and f.

[0084] According to the physical dimensions of the first antenna arm 1 and the second antenna arm 2 , different functions of the antenna structure may be achieved by adjusting the first tuning device 3 and the second tuning device 4 .

[0085] As an optional embodiment, Figures 6 to 9 As shown, when the size of the second antenna arm 2 is smaller than the size of the first antenna arm 1:

[0086] The structure of the first matching network 31 is the same as the structure of the second matching network 41;

[0087] The structure of the first tuning network 33 is the same as the structure of the second tuning network 43;

[0088] The N is the same as the M, and the first device is the same as the second device.

[0089] In this embodiment, taking the first antenna arm as the antenna arm of the main antenna and the second antenna arm 2 as the parasitic antenna arm as an example, when the physical size of the parasitic antenna arm is smaller than the antenna arm size of the main antenna, the matching network connected to the parasitic antenna arm and the matching network connected to the main antenna are basically consistent in topological form and device values ​​(it should be noted that they can be slightly adjusted according to the environmental differences between the main antenna and the parasitic antenna); the tuning network connected to the parasitic antenna arm and the tuning network connected to the main antenna are basically consistent in topological form and device values ​​(it should be noted that they can be slightly adjusted according to the environmental differences between the main antenna and the parasitic antenna); the matching network of the main antenna is connected to the radio frequency circuit, and the matching network of the parasitic antenna is connected to the ground under the load; the matching network and the tuning network may both include switching devices, and when including switching devices, the number and device values ​​of the switching devices connected to the main antenna and the switching devices connected to the parasitic antenna arm are basically consistent.

[0090] for Figures 6 to 9 The antenna structure shown in the figure uses the side lobe level (S11) to illustrate the principle of the antenna structure. In order to obtain the S11 of the parasitic antenna, it is necessary to adjust the side lobe level (S11) during the debugging test. Figures 6 to 9Remove the load shown in the figure and connect a network analyzer to it, then the S11 of the parasitic antenna can be measured. For an antenna without a switch, Fig.12 As shown in the figure, the three modes of the first antenna arm (i.e., the main antenna) correspond to the operating frequency bands f4, f5, and f6. Since the physical size of the parasitic antenna is shorter than that of the main antenna, under the basically identical matching network, the three modes of the parasitic antenna are consistent with those of the main antenna, except that the operating frequencies are f1, f2, and f3, which are correspondingly higher than the three operating frequencies of the main antenna. For antennas with switches, such as Fig.13 As shown, this is the situation in switch state 1, the main antenna works at f8. Since the physical size of the parasitic antenna is shorter than that of the main antenna, under basically the same matching network (including the switch state), the operating frequency f7 of the parasitic antenna will be higher than f8; when the switch is switched to switch state 2, by the same token, the operating frequency f9 of the parasitic antenna is higher than the operating frequency f10 of the main antenna, and the same is true for the other switch states.

[0091] It should be noted that the antenna structure of the embodiment of the present application includes but is not limited to Figures 6 to 9 The antenna forms shown are monopole, IFA, PIFA, LOOP, etc.

[0092] As an optional embodiment, when the size of the second antenna arm 2 is smaller than the size of the first antenna arm 1, the N is twice the M;

[0093] When the second antenna arm 2 is coupled to the first antenna arm 1, if the first switch 34 is connected to a first target device among the M first devices, and the second switch 44 is connected to a second target device among the N second devices, the antenna structure is in a first operating mode;

[0094] If the first switch 34 is connected to a first target device among the M first devices, and the second switch 44 is connected to a third target device among the N second devices, the antenna structure is in the second operating mode.

[0095] In this embodiment, the first switch 34 is connected to the first target device among the M first devices, which can be considered that the first tuning device 3 is in the first state; the second switch 44 is connected to the second target device among the N second devices, which can be considered that the second tuning device 4 is in the second state, and the antenna structure is in the first working mode. The second switch 44 is connected to the third target device among the N second devices, which can be considered that the second tuning device 4 is in the third state, and the antenna structure is in the second working mode.

[0096] When the size of the second antenna arm 2 is smaller than that of the first antenna arm 1, the purpose of reducing SAR can be achieved by adding more switching states to the matching network or tuning network of the second antenna arm, that is, the number of devices connected to the second switch 44 connected to the second antenna arm 2 is set to be twice the number of devices connected to the first switch 34 connected to the first antenna arm 1, for example Fig.10 and Fig.11 As shown. The first antenna arm 1 is the antenna arm of the main antenna, and the second antenna arm 2 is the parasitic antenna arm. Fig.10 In the embodiment, two switch states are added to the second switch 44 in the second matching network 41 of the parasitic antenna (if the number of switch states of the main antenna is n, the parasitic antenna needs to have 2n states, Fig.10 The switch of the main antenna has two states, so the parasitic antenna only needs 4 states). Fig.11 The second switch 44 in the second tuning network 43 of the parasitic antenna adds two switch states.

[0097] Fig.10 and Fig.11 This is to illustrate the topological structure performance of the implementation method under two antenna forms. The antenna forms include but are not limited to monopole, IFA, PIFA, LOOP and other antenna forms, and the switch topology is not limited to Fig.10 and Fig.11 shown.

[0098] by Fig.10 For example, assuming that when the first switch 34 is connected to device a (ie, the first target device), the operating frequency of the main antenna is f1, such as Fig.14 As shown. If the second switch 44 is connected to device c (i.e., the second target device), the parasitic antenna operating frequency is also at f1. At this time, the current in the direction of the parasitic antenna is the largest, and the SAR reduction effect is the best, which is a low SAR state, that is, the antenna structure works in the first working mode. If the second switch 44 is connected to device d (i.e., the third target device), the parasitic antenna operating frequency is f3. At this time, the parasitic antenna current becomes smaller, the SAR reduction effect becomes weaker, and the antenna efficiency of the main antenna is improved, which is a high antenna efficiency state, that is, the antenna structure works in the second working mode.

[0099] Similarly, when the first switch 34 is connected to device b (the device b can be the first target device at this time), the main antenna operating frequency is f2. If the second switch 44 is connected to device e (the device e is the second target device at this time), the parasitic antenna operating frequency is also f2, at which time the current in the direction of the parasitic antenna is the largest, the SAR reduction effect is the best, and it is in a low SAR state, that is, the antenna structure works in the first working mode; if the second switch 44 is connected to device f (the device f is the third target device at this time), the parasitic antenna operating frequency is f4, at which time the parasitic antenna current becomes smaller, the SAR reduction effect becomes weaker, and the antenna efficiency of the main antenna is improved, which is a high antenna efficiency state, that is, the antenna structure works in the second working mode.

[0100] As an optional embodiment, when the size of the second antenna arm 2 is the same as the size of the first antenna arm 1, the N is the same as the M, and the first component is different from the second component;

[0101] When the second antenna arm 2 is coupled to the first antenna arm 1, if the first switch 34 is connected to a first target device among the M first devices, and the second switch 44 is connected to a second target device among the N second devices, the antenna structure is in a first operating mode;

[0102] If the first switch 34 is connected to a first target device among the M first devices, and the second switch 44 is connected to a third target device among the N second devices, the antenna structure is in the second operating mode.

[0103] In this embodiment, when the size of the second antenna arm 2 is the same as the size of the first antenna arm 1, relative to Fig.10 and Fig.11 The antenna structure shown can reduce the number of switch states of the second antenna arm 2 to the same number of switch states as the first antenna arm, for example Fig.15 As shown. The first antenna arm 1 is the antenna arm of the main antenna, and the second antenna arm 2 is the parasitic antenna arm. Fig.15 In the embodiment, the number of states of the second switches 44 connected to the second matching network 41 of the parasitic antenna is consistent with the number of states of the first switches 34 connected to the first matching network 31 of the main antenna.

[0104] When the first switch 34 is connected to device a (ie, the first target device), the operating frequency of the main antenna is f1. Fig.16If the second switch 44 is connected to device c (i.e., the second target device), the parasitic antenna operating frequency is also at f1, at which time the current in the direction of the parasitic antenna is the largest, the SAR reduction effect is the best, and it is in a low SAR state, and the antenna structure works in the first working mode; if the second switch 44 is connected to device d (i.e., the third target device), the parasitic antenna operating frequency is f3, at which time the parasitic antenna current becomes smaller, the SAR reduction effect becomes weaker, the antenna efficiency of the main antenna is improved, and it is in a high antenna efficiency state, and the antenna structure works in the second working mode.

[0105] Similarly, when the first switch 34 is connected to device b (device b is the first target device at this time), the main antenna operating frequency is f2. If the second switch 44 is connected to device d (device d is the second target device at this time), the parasitic antenna operating frequency is also f2, at this time the current in the direction of the parasitic antenna is the largest, the SAR reduction effect is the best, it is a low SAR state, and the antenna structure works in the first working mode; if the second switch 44 is connected to device c (device c is the third target device at this time), the parasitic antenna operating frequency is f1, at this time the parasitic antenna current becomes smaller, the SAR reduction effect becomes weaker, the antenna efficiency of the main antenna is improved, it is a high antenna efficiency state, and the antenna structure works in the second working mode.

[0106] In this embodiment, when the electronic device detects that the antenna structure is close to the human body, the switching states of the first switch 34 and the second switch 44 can be controlled to make the antenna structure operate in the first operating mode, i.e., the low SAR state, thereby avoiding a greater impact of the antenna on the human body; when the antenna is far away from the human body, the switching states of the first switch 34 and the second switch 44 can be controlled to make the antenna structure operate in the second operating mode, i.e., the high antenna efficiency state, thereby improving the antenna efficiency.

[0107] The embodiments of the present application can reduce the impact of the antenna on the human body when the human body is close to the antenna in a low SAR state; in a high antenna efficiency state, it can reduce the impact of the reverse current of the parasitic antenna and improve the antenna efficiency; the implementation method of the embodiments of the present application only needs to add some devices with the same topology as the main antenna matching network or tuning network, which can be capacitors, inductors, and switching devices, without a large investment in cost.

[0108] It should be noted that in the embodiments of the present application, the specific form of the antenna is not limited, and the antenna form can be a monopole, IFA, PIFA, LOOP, etc.; the topological structure of the switch is not limited, and this embodiment only shows some topological forms, and any topological form that can be used in the antenna is actually available; the implementation of the present application does not limit the switch model and device model, and any device that meets the antenna function is available; the implementation of the present application does not limit the operating frequency range and the number of operating frequency bands of the antenna, and does not make specific requirements on the position of the antenna on the electronic device, as long as the spatial coupling path generates a reverse current.

[0109] In an embodiment of the present application, the antenna structure includes a first antenna arm and a second antenna arm, the first antenna arm is connected to a first tuning device, and the second antenna arm is connected to a second tuning device. When the first antenna arm and the second antenna arm are coupled, the first tuning device and the second tuning device can be adjusted according to the distance between the antenna structure and the human body, so that the antenna structure operates in a first working mode with a lower SAR, thereby reducing the impact on the human body; or the antenna structure operates in a second working mode with a higher antenna efficiency, thereby improving the antenna efficiency. The antenna structure can meet different working requirements.

[0110] An embodiment of the present application further provides an electronic device, comprising the above antenna structure; the electronic device further comprises:

[0111] A first body and a second body, wherein the first body and the second body are movable relative to each other;

[0112] The first antenna arm 1 is arranged on the first main body, and there is a clearance area between the first antenna arm 1 and the first main body;

[0113] The second antenna arm 2 is disposed on the second body, and a clearance area is provided between the second antenna arm 2 and the second body.

[0114] In this embodiment, the electronic device may be a folding screen device, that is, the first body and the second body are respectively two parts of the body where the folding screen is located, and when the electronic device changes between the unfolded state and the folded state, the distance between the first body and the second body changes, and the distance between the first antenna arm 1 and the second antenna arm 2 changes; or, the electronic device may also be a device including two parts of the body that can move relative to each other, for example, a retractable camera structure is provided on the body of the electronic device, the first antenna arm 1 is provided on the body of the electronic device, and the second antenna arm 2 is provided on the retractable camera structure, and the second antenna arm 2 is driven to move through the retractable movement of the retractable camera structure, thereby realizing the change of the distance between the first antenna arm 1 and the second antenna arm 2.

[0115] There is a clearance area between the first antenna arm 1 and the first body, and there is a clearance area between the second antenna arm 2 and the second body, so as to prevent the metal frame of the electronic device from affecting the antenna performance.

[0116] Take the electronic device as an example, which is an electronic device with a foldable screen. Fig.17 As shown, it includes part A and part B, wherein the first antenna arm 1 is arranged in the part B, and the second antenna arm 2 is arranged in the part A. Taking the first antenna arm 1 as the antenna arm of the main antenna and the second antenna arm 2 as the parasitic antenna arm as an example, there is a first clearance area 22 between the first antenna arm 1 and the part B, and a first break 24 between the first antenna arm 1 and the frame of the part B; there is a second clearance area 23 between the second antenna arm 2 and the part A, and there is a second break 25 between the second antenna arm 2 and the frame of the part A. When the electronic device is in a folded state, the part A and the part B are close to each other and folded as shown in FIG. Fig.18 As shown, the second antenna arm 2 and the first antenna arm 1 are coupled to generate a reverse current, such as Fig.18 As indicated by the arrow in .

[0117] Wherein, when the main antenna (ie, the first antenna arm 1) is working, the parasitic antenna arm (ie, the second antenna arm 2) may be excited in two ways, such as: Fig.19 As shown in the figure, excitation path a indicates that the main antenna excites the current on the parasitic branch through spatial coupling, and excitation path b indicates that the main antenna excites the current on the parasitic branch through the hinge structure through the ground current. Excitation path a has a great influence mainly in the folded state, and has a greater influence on medium and high frequencies (above 1GHz).

[0118] In an embodiment of the present application, the electronic device includes the antenna structure. When the first antenna arm is working, if the first antenna arm and the second antenna arm are coupled, the first tuning device connected to the first antenna arm and the second tuning device connected to the second antenna arm can be adjusted according to the distance between the electronic device and the human body, so that the antenna structure works in a first working mode with lower SAR, thereby reducing the impact on the human body; or the antenna structure works in a second working mode with higher antenna efficiency, thereby improving the antenna efficiency and meeting different working requirements.

[0119] like Fig. 20 As shown, the embodiment of the present application also provides an antenna working mode switching method, which is applied to Figures 1 to 16 The antenna structure shown, the method comprises:

[0120] Step 201: When the first antenna arm and the second antenna arm are in a coupled state, detecting the distance between the antenna structure and the human body;

[0121] Step 202: According to the distance, the antenna structure is placed in a first working mode or a second working mode by adjusting the states of the first tuning device and the second tuning device;

[0122] The SAR of the antenna structure in the first working mode is less than a first threshold, and / or the antenna efficiency of the antenna structure in the second working mode is greater than a second threshold.

[0123] In this embodiment, when the first antenna arm and the second antenna arm are coupled, the second antenna arm generates a reverse current. In order to reduce the impact of the reverse current on the human body or avoid affecting the antenna performance, the working mode of the antenna structure can be adjusted as needed.

[0124] The working modes of the antenna structure include: a first working mode, in which the SAR of the antenna structure is less than a first threshold, indicating that the antenna structure is in a low SAR state; a second working mode, in which the antenna efficiency of the antenna structure is greater than a second threshold, indicating that the antenna structure is in a high antenna efficiency state. Both the first threshold and the second threshold can be set according to the antenna radiation requirements and the impact test on the human body.

[0125] According to the distance between the antenna structure and the human body, the working mode of the antenna structure can be adjusted by adjusting the working states of the first tuning device and the second tuning device. For example, when the antenna structure is close to the human body, the antenna structure is in the first working mode, that is, the antenna structure is in a low SAR state and has little impact on the human body; when the antenna structure is far away from the human body, the impact on the human body is small, the radiation performance of the antenna can be improved, and the antenna structure is in the second working mode.

[0126] As an optional embodiment, according to the distance, by adjusting the states of the first tuning device and the second tuning device, the antenna structure is placed in the first working mode or the second working mode, including:

[0127] When the distance is less than or equal to a third threshold, the antenna structure is placed in a first working mode by adjusting the states of the first tuning device and the second tuning device;

[0128] or,

[0129] When the distance is greater than a third threshold, the antenna structure is placed in a second working mode by adjusting the states of the first tuning device and the second tuning device.

[0130] In this embodiment, the third threshold is a safe distance between the human body and the antenna structure. When the distance is less than or equal to the safe distance, it is considered that the antenna has a greater impact on the human body when it is working. When the distance is greater than the third threshold, it is considered that the antenna structure has a smaller impact on the human body when it is working.

[0131] The electronic device can detect the distance between the antenna structure and the human body. When the distance between the antenna structure and the human body is less than or equal to the third threshold, it is considered that the antenna has a greater impact on the human body and the SAR needs to be reduced. The first tuning device and the second tuning device are adjusted to make the antenna structure work in the first working mode, that is, the low SAR state. When the distance between the antenna structure and the human body is greater than the third threshold, it is considered that the antenna structure has a less impact on the human body and the working efficiency of the antenna should be guaranteed. The first tuning device and the second tuning device can be adjusted to make the antenna structure work in the second working mode, that is, the high antenna efficiency state.

[0132] As an optional embodiment, when the distance is less than or equal to a third threshold, adjusting the states of the first tuning device and the second tuning device so that the antenna structure is in the first working mode includes:

[0133] When the distance is less than or equal to a third threshold, the first tuning device is adjusted to a first state and the second tuning device is adjusted to a second state; wherein, when the first tuning device is in the first state and the second tuning device is in the second state, the antenna structure is in the first working mode.

[0134] Optionally, adjusting the first tuning device to a first state and adjusting the second tuning device to a second state includes: controlling a first switch in the first tuning device to connect to a first target device among M first devices, and controlling a second switch in the second tuning device to connect to a second target device among N second devices.

[0135] In this embodiment, when the antenna structure needs to work in a low SAR state (i.e., the antenna structure is close to the human body), the first tuning device can be placed in a first state, i.e., the first switch in the first tuning device is connected to the first target device among the M first devices; and the second tuning device is adjusted to a second state, i.e., the second switch in the second tuning device is connected to the second target device among the N second devices. In this state, the excitation current generated by the second antenna arm (i.e., the parasitic antenna arm) in the antenna structure is the largest, the SAR reduction effect is the best, and it is a low SAR state, which can reduce the impact of the antenna operation on the human body.

[0136] As an optional embodiment, when the distance is greater than a third threshold, adjusting the states of the first tuning device and the second tuning device so that the antenna structure is in the second working mode includes:

[0137] When the distance is greater than a third threshold, the first tuning device is adjusted to a first state, and the second tuning device is adjusted to a third state; wherein, when the first tuning device is in the first state and the second tuning device is in the third state, the antenna structure is in the second working mode.

[0138] Optionally, adjusting the first tuning device to the first state and adjusting the second tuning device to the third state includes: controlling a first switch in the first tuning device to connect to a first target device among M first devices, and controlling a second switch in the second tuning device to connect to a third target device among N second devices.

[0139] In this embodiment, when the antenna structure needs to work in a high antenna efficiency state (i.e., the antenna structure is far away from the human body and has high antenna performance requirements), the first tuning device can be placed in a first state, i.e., the first switch in the first tuning device is connected to the first target device among the M first devices; and the second tuning device is adjusted to a third state, i.e., the second switch in the second tuning device is connected to the third target device among the N second devices. In this state, the excitation current generated by the second antenna arm (i.e., the parasitic antenna arm) in the antenna structure becomes smaller, the SAR reduction effect is weakened, and the efficiency of the main antenna is improved, which is a high antenna efficiency state.

[0140] In an embodiment of the present application, when the first antenna arm and the second antenna arm of the antenna structure are coupled, based on the distance between the antenna structure and the human body, when the distance is less than or equal to a third threshold, the antenna structure is switched to the first operating mode by adjusting the states of the first tuning device and the second tuning device, thereby achieving low SAR and reducing the impact of the antenna on the human body; when the distance is greater than the third threshold, the antenna structure is switched to the second operating mode by adjusting the states of the first tuning device and the second tuning device, thereby achieving higher antenna efficiency and meeting different working requirements.

[0141] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0142] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. An antenna structure, characterized in that: include: A first antenna arm (1); A second antenna arm (2), wherein the distance between the second antenna arm (2) and the first antenna arm (1) is variable; A first tuning device (3) connected to the first antenna arm (1); A second tuning device (4) connected to the second antenna arm (2); When the second antenna arm (2) is in a coupled state with the first antenna arm (1), the antenna structure comprises a first working mode and a second working mode, and the working mode of the antenna structure is related to the distance between the antenna structure and the human body; Wherein, if the first tuning device (3) is in a first state and the second tuning device (4) is in a second state, the antenna structure is in a first working mode; if the first tuning device (3) is in a first state and the second tuning device (4) is in a third state, the antenna structure is in a second working mode; Wherein, the electromagnetic wave specific absorption rate SAR of the antenna structure in the first working mode is less than a first threshold value, and / or the antenna efficiency of the antenna structure in the second working mode is greater than a second threshold value; The first tuning device (3) comprises: A first matching network (31) and a radio frequency circuit (32), wherein a first end of the first matching network (31) is connected to the first antenna arm (1), and a second end of the first matching network (31) is connected to the radio frequency circuit (32); The second tuning device (4) comprises a second matching network (41) and a load (42), wherein a first end of the second matching network (41) is connected to the second antenna arm (2), a second end of the second matching network (41) is connected to the load (42), and the load (42) is grounded.

2. The antenna structure according to claim 1, characterized in that: The first antenna arm (1) and the second antenna arm (2) have the same size; or, The size of the second antenna arm (2) is smaller than the size of the first antenna arm (1).

3. The antenna structure according to claim 1, characterized in that: The first tuning device (3) further comprises: a first tuning network (33), wherein the first tuning network (33) is connected to the first antenna arm (1); The second tuning device (4) further comprises: a second tuning network (43), wherein the second tuning network (43) is connected to the second antenna arm (2).

4. The antenna structure according to claim 1 or 3, characterized in that: The first tuning device (3) further comprises: a first switch (34), the first switch (34) being connected to the M first devices respectively, and when the first switch (34) is connected to different first devices, the operating frequency of the first antenna arm (1) is different; The second tuning device (4) further comprises: a second switch (44), the second switch (44) being connected to the N second devices respectively, and when the second switch (44) is connected to different second devices, the operating frequency of the second antenna arm (2) is different; The first switch (34) is connected to the first matching network (31), and the second switch (44) is connected to the second matching network (41); or the first switch (34) is connected to the first tuning network (33), and the second switch (44) is connected to the second tuning network (43); Among them, M is greater than or equal to 1, and N is greater than or equal to 2.

5. The antenna structure according to claim 4, characterized in that: When the size of the second antenna arm (2) is smaller than the size of the first antenna arm (1): The structure of the first matching network (31) is the same as the structure of the second matching network (41); The structure of the first tuning network (33) is the same as the structure of the second tuning network (43); The N is the same as the M, and the first device is the same as the second device.

6. The antenna structure according to claim 4, characterized in that: When the size of the second antenna arm (2) is smaller than the size of the first antenna arm (1), N is twice the size of M; When the second antenna arm (2) and the first antenna arm (1) are in a coupled state, if the first switch (34) is connected to a first target device among the M first devices, and the second switch (44) is connected to a second target device among the N second devices, then the antenna structure is in a first working mode; If the first switch (34) is connected to a first target device among the M first devices, and the second switch (44) is connected to a third target device among the N second devices, the antenna structure is in a second operating mode.

7. The antenna structure according to claim 4, characterized in that: When the size of the second antenna arm (2) is the same as the size of the first antenna arm (1), the N is the same as the M, and the first device is different from the second device; When the second antenna arm (2) and the first antenna arm (1) are in a coupled state, if the first switch (34) is connected to a first target device among the M first devices, and the second switch (44) is connected to a second target device among the N second devices, then the antenna structure is in a first working mode; If the first switch (34) is connected to a first target device among the M first devices, and the second switch (44) is connected to a third target device among the N second devices, the antenna structure is in a second operating mode.

8. An electronic device, characterized in that: The electronic device comprises the antenna structure according to any one of claims 1 to 7; the electronic device further comprises: A first body and a second body, wherein the first body and the second body are movable relative to each other; The first antenna arm (1) is arranged on the first main body, and a clearance area is provided between the first antenna arm (1) and the first main body; The second antenna arm (2) is arranged on the second main body, and a clearance area is provided between the second antenna arm (2) and the second main body.

9. A method for switching an antenna working mode, characterized in that: The antenna structure as claimed in claim 1 comprises: When the first antenna arm and the second antenna arm are in a coupled state, detecting the distance between the antenna structure and the human body; According to the distance, the antenna structure is placed in a first working mode or a second working mode by adjusting the states of the first tuning device and the second tuning device; The SAR of the antenna structure in the first working mode is less than a first threshold, and / or the antenna efficiency of the antenna structure in the second working mode is greater than a second threshold.

10. The method according to claim 9, characterized in that According to the distance, the antenna structure is placed in the first working mode or the second working mode by adjusting the states of the first tuning device and the second tuning device, including: When the distance is less than or equal to a third threshold, the antenna structure is placed in a first working mode by adjusting the states of the first tuning device and the second tuning device; or, When the distance is greater than a third threshold, the antenna structure is placed in a second working mode by adjusting the states of the first tuning device and the second tuning device.

11. The method according to claim 10, characterized in that When the distance is less than or equal to a third threshold, the antenna structure is placed in a first working mode by adjusting the states of the first tuning device and the second tuning device, including: When the distance is less than or equal to a third threshold, adjusting the first tuning device to a first state and adjusting the second tuning device to a second state; Wherein, when the first tuning device is in the first state and the second tuning device is in the second state, the antenna structure is in the first working mode.

12. The method according to claim 11, characterized in that The step of adjusting the first tuning device to a first state and adjusting the second tuning device to a second state comprises: A first switch in the first tuning device is controlled to be connected to a first target device in the M first devices, and a second switch in the second tuning device is controlled to be connected to a second target device in the N second devices.

13. The method according to claim 10, characterized in that When the distance is greater than a third threshold, the antenna structure is placed in a second working mode by adjusting the states of the first tuning device and the second tuning device, including: When the distance is greater than a third threshold, adjusting the first tuning device to a first state, and adjusting the second tuning device to a third state; Wherein, when the first tuning device is in the first state and the second tuning device is in the third state, the antenna structure is in the second working mode.

14. The method according to claim 13, characterized in that The step of adjusting the first tuning device to a first state and adjusting the second tuning device to a third state comprises: A first switch in the first tuning device is controlled to be connected to a first target device among the M first devices, and a second switch in the second tuning device is controlled to be connected to a third target device among the N second devices.

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