Foldable electronic equipment

Abstract

The embodiment of the invention discloses foldable electronic equipment, the foldable electronic equipment comprises a first main body, a second main body and a rotating shaft, the first main body and the second main body are connected through the rotating shaft, the foldable electronic equipment can be folded at the rotating shaft, the first main body comprises a first metal frame, and the second main body comprises a second metal frame; the first metal frame comprises a first open end and a second open end; a first grounding point and a second grounding point are arranged on the first metal frame; a first feeding point is arranged between the first grounding point and the first open end, and a second feeding point is arranged between the second grounding point and the second open end; the second main body comprises a second metal frame with two open ends. According to the embodiment of the invention, the radiation performance of the antenna can be improved.

Description

A foldable electronic device

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on December 26, 2023, with application number 202311815859.3 and application name “A Foldable Electronic Device”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of wireless communication technology, and in particular to a foldable electronic device. Background Art

[0003] As mobile phones continue to evolve, they need to support more and more frequency bands, and the requirements for communication quality are becoming increasingly stringent. However, when a foldable phone is folded, the wireless signal transmission and reception performance will decrease, affecting the user's communication experience.

[0004] Summary of the Invention

[0005] An embodiment of the present application discloses a foldable electronic device that can improve the radiation effect of an antenna.

[0006] In the first aspect, the present application provides a foldable electronic device, which includes a first body, a second body and a hinge, the first body and the second body are connected by the hinge, and the foldable electronic device can be folded at the hinge, wherein: the first body includes a first metal frame, the first metal frame includes a first open end and a second open end; a first grounding point and a second grounding point are provided on the first metal frame; a first feeding point is provided between the first grounding point and the first open end, and a second feeding point is provided between the second grounding point and the second open end; the second body includes a second metal frame, and both ends of the second metal frame are open.

[0007] In an embodiment of the present application, the radiation branches of the first antenna and the second antenna are designed to the first metal frame, which can ensure the support and aesthetics of the metal frame and is also conducive to the miniaturization of the antenna design. In the folded state of the foldable electronic device, in order to avoid the second body blocking the signals of the first antenna and the second antenna, resulting in signal difference, the design of the second metal frame and the first metal frame can make the second metal frame further radiate the signal of the first antenna and / or the second antenna, thereby improving the radiation performance of the antenna. In addition, the first grounding point and the second grounding point are respectively provided with feeding points to the corresponding open ends to ensure the isolation between the feeding antennas.

[0008] In one possible embodiment, the second metal frame is a suspended structure. Thus, the second metal frame is designed as a suspended structure so that the second metal frame is coupled to the first metal frame, further radiating the radiation signal of the first metal frame outward, thereby ensuring antenna performance.

[0009] In one possible embodiment, when the foldable electronic device is in the folded state, the projection of the second metal frame on the plane of the first body at least partially overlaps with the first metal frame. In this way, the second metal frame and the first metal frame are very close in the folded state. This close distance ensures that the second metal frame can couple to the first metal frame, thereby achieving an enhanced antenna effect.

[0010] In one possible embodiment, the at least partial overlap specifically includes: the projection of the second metal frame on the plane where the first body is located overlaps at least half of the length direction of the first section of the first metal frame; the first section of the first metal frame is the metal frame from the first open end to the first grounding point; or, the projection of the second metal frame on the plane where the first body is located overlaps at least half of the length direction of the second section of the first metal frame; the second section of the second metal frame is the metal frame from the second open end to the second grounding point. In this way, the above-mentioned design structure of the first metal frame and the second metal frame can ensure that the second metal frame can be coupled to the first metal frame, so that the first antenna further radiates outward.

[0011] In one possible embodiment, the at least partial overlap specifically includes: the projection of the second metal frame on the plane of the first body completely overlaps the first metal frame. In this way, the design structure of the first and second metal frames is such that the second metal frame can be coupled with the first metal frame, thereby achieving a better radiation effect.

[0012] In one possible embodiment, the foldable electronic device further includes a first antenna and a second antenna disposed on the first body; the first metal frame includes a first section and a second section, wherein the first section of the first metal frame is the metal frame extending from the first open end to the first grounding point; and the second section of the second metal frame is the metal frame extending from the second open end to the second grounding point; the first antenna includes the first section of the first metal frame; and the second antenna includes the second section of the first metal frame. Thus, the first section of the first metal frame can serve as a partial radiating branch of the first antenna, and the second section can serve as a partial radiating branch of the second antenna, thereby generating signal radiation.

[0013] In one possible embodiment, when the first antenna is fed at a first frequency, the first metal frame generates a first current at the first frequency in a direction from the first feeding point to the first grounding point. When the second metal frame is coupled to the first antenna, a second current is generated on the second metal frame at the first frequency in a direction from the third open end to the fourth open end. The first current and the second current have the same direction. Thus, when the first antenna is fed, the second metal frame generates a current in the same direction as the first segment, thereby enhancing the signal radiation strength of the first antenna and improving the antenna efficiency of the first antenna.

[0014] In one possible embodiment, the first metal frame generates a third current at a fourth frequency in a direction from the first open end to the second open end; the second metal frame generates a fourth current at the fourth frequency in a direction from the fourth open end to the third open end; the third current and the fourth current are in opposite directions, and the fourth frequency is greater than the first frequency. Thus, at the out-of-band frequency point of the first antenna (the fourth frequency), the current direction of the second metal frame is opposite to the current direction of the first metal frame, resulting in cancellation of the out-of-band radiation signal, thereby improving the in-band antenna efficiency of the first antenna.

[0015] In one possible embodiment, when the second antenna is fed at a second frequency, the first metal frame generates a fifth current at the second frequency in a direction from the second feeding point to the second grounding point. When the second metal frame is coupled to the second antenna, a sixth current is generated on the second metal frame at the second frequency in a direction from the fourth open end to the third open end. The fifth current and the sixth current have the same direction. Thus, when the second antenna is fed, the second metal frame generates a current in the same direction as the second segment, thereby enhancing the signal radiation strength of the second antenna and improving the antenna efficiency of the second antenna.

[0016] In one possible embodiment, the first metal frame generates a seventh current at a fifth frequency in a direction from the second open end to the first open end; the second metal frame generates an eighth current at the fifth frequency in a direction from the third open end to the fourth open end; the seventh current is in the opposite direction to the eighth current, and the fifth frequency is greater than the second frequency. Thus, at the out-of-band frequency point of the second antenna (the fifth frequency), the current direction of the second metal frame is opposite to the current direction of the first metal frame, resulting in cancellation of the out-of-band radiation signal, thereby improving the in-band antenna efficiency of the second antenna.

[0017] In a possible implementation, the resonant frequency of the first antenna is a first frequency, the resonant frequency of the second antenna is a second frequency, and both the first frequency and the second frequency are within a cellular frequency band.

[0018] In a possible implementation manner, the first frequency is the same as the second frequency.

[0019] In one possible implementation, the distance from the first grounding point to the first open end is smaller than the distance from the second grounding point to the first open end; and the distance from the second grounding point to the second open end is smaller than the distance from the first grounding point to the second open end. In this way, the first and second grounding points are defined at the locations of the first metal frame, ensuring that the corresponding radiation branches of the first and second antennas do not cross or overlap, thereby ensuring the reliability and rationality of radiation from both antennas.

[0020] In one possible embodiment, the length of the second metal frame is greater than or equal to 1 / 2 of the first wavelength, where the first wavelength is the maximum of the first operating wavelength and the second operating wavelength, the first operating wavelength is the wavelength of the signal radiated by the first antenna, and the second operating wavelength is the wavelength of the signal radiated by the second antenna. In this way, the second metal frame can generate a resonant frequency greater than the operating frequency of the first antenna and / or the second antenna, causing resonance to occur out of band above the communication frequency band of the first antenna and / or the second antenna, forming a local minimum in antenna efficiency. This, in contrast, improves the operating efficiency of the first antenna and / or the second antenna.

[0021] In a possible embodiment, the first section of the first metal frame is connected to a first frequency modulation circuit, and the first frequency modulation circuit is used to adjust the resonant frequency of the first antenna to a first frequency; the second section of the first metal frame is connected to a second frequency modulation circuit, and the second section is used to adjust the resonant frequency of the second antenna to a second frequency; the second metal frame is connected to a third frequency modulation circuit, and is used to adjust the resonant frequency of the second metal frame to a third frequency; the third frequency is the same as the first frequency, and / or the third frequency is the same as the second frequency.

[0022] In one possible embodiment, the second metal frame has a third grounding point, and the third frequency modulation circuit includes a fourth frequency modulation circuit and a fifth frequency modulation circuit; the fourth frequency modulation circuit is disposed on one side of the third grounding point, and the fifth frequency modulation circuit is disposed on the other side of the third grounding point. The fourth and fifth frequency modulation circuits can adjust the frequencies of the first and second antennas, respectively, thereby re-radiating the radiated signals of the first and second antennas, providing the ability to independently adjust and enhance the radiation performance of the two antennas.

[0023] In one possible implementation, when the foldable electronic device is in the folded state, the projection of the third ground point on the plane of the first body is located between the first ground point and the second ground point. This position of the third ground point is intermediate between the first and second antenna signals, allowing the second metal frame to couple with the first metal frame in the folded state, improving outward radiation performance.

[0024] In one possible implementation, when the foldable electronic device is in the folded state, the projection of the third ground point on the plane of the first body overlaps with the first ground point or the second ground point. This allows the third ground point to be positioned midway between the isolation between the first and second antenna signals. This allows the second metal frame to couple with the first metal frame in the folded state, improving outward radiation performance.

[0025] In a second aspect, the present application provides an antenna system, which includes any one of the foldable electronic devices of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] FIG1A to FIG1C are schematic structural diagrams of a group of foldable electronic devices 100 provided in an embodiment of the present application;

[0027] 2A and 2B are schematic diagrams of an antenna system for a foldable electronic device according to an embodiment of the present application;

[0028] 3A to 3C are schematic structural diagrams of a group of antenna systems in an unfolded state provided by an embodiment of the present application;

[0029] FIG4A is a schematic diagram of S-parameter curves of a first antenna and a second antenna when the electronic device is in an unfolded state according to an embodiment of the present application;

[0030] FIG4B is a schematic diagram of antenna efficiency curves of a first antenna and a second antenna of an electronic device in an unfolded state provided by an embodiment of the present application;

[0031] 5A to 5C are schematic diagrams showing current flows at different frequencies in the first metal frame of FIG. 3B according to an embodiment of the present application;

[0032] FIG6 is a schematic diagram of a folded antenna structure provided by an embodiment of the present application;

[0033] FIG7 is a schematic diagram of a circuit structure of the antenna system in FIG6 provided in an embodiment of the present application;

[0034] FIG8A is a schematic diagram of S-parameter curves of a first antenna and a second antenna when the electronic device is in a folded state, provided by an embodiment of the present application;

[0035] FIG8B is a schematic diagram of antenna efficiency curves of a first antenna and a second antenna when an electronic device provided by an embodiment of the present application is in a folded state;

[0036] 9A to 9D are schematic diagrams showing current flows of a first metal frame and a second metal frame at different frequencies provided by an embodiment of the present application;

[0037] 10A and 10B are schematic diagrams of an antenna system of another foldable electronic device 100 provided in an embodiment of the present application;

[0038] FIG11 is a schematic diagram of the antenna structure of the electronic device in FIG10A in a folded state according to an embodiment of the present application;

[0039] FIG12 is a schematic diagram of a circuit structure of an antenna system provided in an embodiment of the present application;

[0040] FIG13A is a schematic diagram of S-parameter curves of a first antenna and a second antenna of an electronic device in a folded state provided by an embodiment of the present application;

[0041] FIG13B is a schematic diagram of antenna efficiency curves of a first antenna and a second antenna of an electronic device in a folded state provided by an embodiment of the present application;

[0042] 14A to 14C are schematic diagrams of another set of antenna systems for foldable electronic devices provided in accordance with an embodiment of the present application;

[0043] FIG15 is a schematic diagram of an antenna structure of the electronic device in FIG14A in a folded state according to an embodiment of the present application;

[0044] FIG16 is a schematic diagram of a circuit structure of an antenna of the electronic device in FIG15 when the antenna is in a folded state, provided by an embodiment of the present application;

[0045] FIG17A is a schematic diagram of S-parameter curves of a first antenna and a second antenna of an electronic device in a folded state provided by an embodiment of the present application;

[0046] FIG17B is a schematic diagram of antenna efficiency curves of a first antenna and a second antenna of an electronic device in a folded state provided by an embodiment of the present application;

[0047] FIG18A and FIG18B are schematic diagrams of an antenna system of another group of foldable electronic devices 100 provided in an embodiment of the present application;

[0048] FIG19A is a schematic diagram of S-parameter curves of a first antenna and a second antenna of an electronic device in a folded state provided by an embodiment of the present application;

[0049] FIG19B is a schematic diagram of antenna efficiency curves of a first antenna and a second antenna of an electronic device in a folded state provided by an embodiment of the present application;

[0050] 20A and 20B are schematic diagrams of another set of antenna systems of a foldable electronic device 100 provided in an embodiment of the present application;

[0051] FIG21A is a schematic diagram of S-parameter curves of a first antenna and a second antenna of an electronic device in a folded state provided by an embodiment of the present application;

[0052] FIG21B is a schematic diagram of antenna efficiency curves of a first antenna and a second antenna of an electronic device in a folded state provided by an embodiment of the present application. DETAILED DESCRIPTION

[0053] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Among them, the drawings are only for illustrative purposes and represent only schematic diagrams and should not be understood as limiting the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0054] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as those commonly understood by those skilled in the art. The terms used in this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0055] 1A and 1B show a schematic structural diagram of a foldable electronic device 100 provided in an embodiment of the present application, wherein the electronic device 100 includes but is not limited to electronic devices such as mobile phones, tablet computers, and wearable devices.

[0056] As shown in Figures 1A and 1B, the electronic device 100 includes a first body 11 and a second body 12 connected to each other. In the embodiment of the present application, the electronic device 100 also includes a hinge 13 provided between the first body 11 and the second body 12. The first body 11 and the second body 12 are connected via the hinge 13, and the first body 11 and the second body 12 can be folded or unfolded relative to each other via the hinge 13, so that the electronic device 100 can have two usage modes. Figure 1A shows a schematic diagram of the structure of the electronic device 100 in the unfolded usage mode, and Figures 1B and 1C show schematic diagrams of the structure of the electronic device 100 in the folded usage mode.

[0057] To facilitate description of the folded state, unfolded state, and dynamic switching between the two states of a foldable electronic device, as shown in Figures 1A and 1B, the foldable electronic device can be divided into four surfaces: a first surface, a second surface, a third surface, and a fourth surface. The first surface is the plane where the first rear cover 421 of the first body 11 is located, the second surface is the plane where the display screen 14 corresponding to the first body 11 is located, the third surface is the plane where the display screen 14 corresponding to the second body 12 is located, and the fourth surface is the plane where the second rear cover 422 of the second body 12 is located.

[0058] The foldable electronic device can be placed in a fully or nearly fully folded state by folding the first body 11 and the second body 12 inward. In this state, the first and fourth surfaces are exposed, and the second and third surfaces may be partially or fully in contact (as shown in FIG1B ). Here, the inward folding can be as shown in FIG1A , where the first body 11 and the second body 12 fold along a first direction 100A.

[0059] The foldable electronic device can also be placed in another fully or nearly fully folded state by folding the first body 11 and the second body 12 outward. In this state, the second and third surfaces are exposed, and the first and fourth surfaces may be partially or fully in contact. Here, the outward folding can be as shown in FIG. 1A , where the first body 11 and the second body 12 fold along the second direction 100B.

[0060] The foldable electronic device can also be in an unfolded state by folding the first body 11 and the second body 12 outward or inward.

[0061] The shaft 13 may also be provided with a connecting structure (not shown), such as a shaft or a hinge structure. The first body 11 and the second body 12 are connected by the connecting structure, and the two can rotate through the connecting structure, so that the two can switch between a relatively folded state and a relatively unfolded state.

[0062] The electronic device 100 also includes a display screen 14 on the first body 11 and the second body 12. The display screen 14 is used to display visual output to the user. The visual output may include graphics, text, icons, videos, etc. The display screen 14 may include a first display portion 141 and a second display portion 142. When the electronic device 100 is in a folded state, it may have a small-area display screen, which can meet the user's need for easy portability. Among them, the display screen 14 may be a flexible screen. When the electronic device 100 is in a folded state, the display screen 14 may be hidden on the inner side of the electronic device 100 or exposed on the outer side of the electronic device 100. This application does not limit the type of the display screen 14 and the presentation method of the display screen 14 when the electronic device 100 is in a folded state. Figure 1B illustrates the example of the display screen 14 being exposed on the outer side of the electronic device 100 when the electronic device 100 is in a folded state.

[0063] The left edge of the electronic device 100 in the unfolded state is the first edge region A; the right edge of the electronic device 100 in the unfolded state is the second edge region B. In the folded state, the projection of the metal frame of the first body 11 in the first edge region A on the plane of the first body 11 and the metal frame of the second body 12 in the second edge region B may at least partially overlap.

[0064] In the embodiments of this application, the available space within the electronic device is compact. To save space, during the antenna design process, a section of the metal frame is often designed to be used as multiple antennas with the same or similar frequencies. This creates an urgent problem of poor isolation that needs to be addressed. Furthermore, when the electronic device is folded, the second edge region B blocks and overlaps the signal from the first edge region A, resulting in low antenna radiation efficiency and poor radiation performance in the first edge region A.

[0065] The present application provides a foldable electronic device, which includes a first body, a second body and a rotating shaft. The first body and the second body are connected by the rotating shaft, and the foldable electronic device can be folded at the rotating shaft, wherein: the first body includes a first metal frame, and the first metal frame is open at both ends, including a first open end and a second open end. A first grounding point and a second grounding point are provided on the first metal frame, the first grounding point is connected to the first grounding branch, and the second grounding point is connected to the second grounding branch. A first feeding point is provided between the first grounding point and the first open end, and a second feeding point is provided between the second grounding point and the second open end. The second body includes a second metal frame, the second metal frame is open at both ends, and the second metal frame is not connected to the feed source. When the foldable electronic device is in a folded state, the first metal frame for feeding is coupled to the second metal frame to radiate electromagnetic waves outward.

[0066] The first body is provided with a first antenna and a second antenna, the first antenna includes a first section of a first metal frame, one end of the first section is open and the other end is grounded; the first section is provided with a feeding point of the first antenna; the second antenna includes a second section of the first metal frame, one end of the second section is open and the other end is grounded; the second section is provided with a feeding point of the second antenna.

[0067] In an embodiment of the present application, the radiation branches of the first antenna and the second antenna are designed to be on a section of metal frame (first metal frame), which can ensure the support of the metal frame, improve the aesthetics of the antenna structure, and save space. However, designing the antenna branches of the two antennas to the same section of metal frame will result in poor isolation between the two antennas. In the antenna system structure of the present application, the feeding process of the first metal frame can form a resonance, and the resonant frequency is different from the resonant frequency of the first antenna and the resonant frequency of the second antenna to improve the isolation between the first antenna and the second antenna. In addition, when the electronic device is in a folded state, the radiation signals of the first antenna and the second antenna can be further radiated at the second metal frame, reducing the obstruction of signal radiation and improving the radiation efficiency of the first antenna and the second antenna.

[0068] In conjunction with Figures 1A and 1B , the left edge of the electronic device 100 in the unfolded state is the first edge region A. The first edge region A includes a first metal frame. The first section of the first metal frame is provided with the first grounding point and the first feeding point of the first antenna, and the second section of the first metal frame is provided with the second grounding point and the second feeding point of the second antenna. That is, the first metal frame has two open ends, namely the first open end and the second open end. The right edge of the electronic device 100 in the unfolded state is the second edge region B. The second edge region B may include a second metal frame, which may be a suspended structure.

[0069] Optionally, when the electronic device is in the folded state, the projection of the second metal frame on the plane where the first body is located at least partially overlaps with the first metal frame, that is, partially overlaps or completely overlaps.

[0070] At least partial overlap may include: the projection of the second metal frame on the plane where the first body is located overlaps with at least half of the first section of the first metal frame; or, the projection of the second metal frame on the plane where the first body is located overlaps with at least half of the second section of the first metal frame. In this way, in the above-mentioned antenna system structure, the radiation efficiency and performance of the first antenna and the second antenna in the folded state can be improved. It can be understood that there is a minimum standard for the length of the overlapping area, which is 1 / 2 of the length of the first section of the first metal frame, or 1 / 2 of the length of the second section of the first metal frame. When the projection of the second metal frame on the plane where the first body is located only overlaps with the first section of the first metal frame, at least 1 / 2 of the length of the first section of the first metal frame overlaps with the projection of the second metal frame on the plane where the first body is located. When the projection of the second metal frame on the plane where the first body is located only overlaps with the second section of the first metal frame, at least 1 / 2 of the length of the second section of the first metal frame overlaps with the projection of the second metal frame on the plane where the first body is located.

[0071] At least partial overlap may include: the projection of the second metal frame on the plane where the first main body is located completely overlaps with the first metal frame. The two open ends of the first metal frame are aligned with the two open ends of the second metal frame respectively. It can be understood that the second metal frame is open at both ends, including a third open end and a fourth open end, wherein the third open end is aligned with the first open end, and the fourth open end is aligned with the second open end. The second metal frame and the first metal frame are equal in length and aligned in position. In this way, it can be ensured that the two second metal frames and the first metal frame are fully coupled, and when the first metal frame is fed with power, the radiation efficiency is higher and the performance is better.

[0072] The fourth edge regions A and B in Figures 1A and 1B are merely illustrative of the spatial location between the first and second metal frames and are not limiting. For example, as shown in Figure 1A, when the electronic device 100 is unfolded, the left bottom frame is the third edge region C, and the right bottom frame is the fourth edge region D. In this case, the first metal frame can be located in the third edge region C, and the second metal frame can be located in the fourth edge region D. Of course, the first and second metal frames can also be located at the top frame or other locations, which will not be explained in detail.

[0073] Fig. 1C shows a schematic diagram of an exploded structure of the electronic device 100. As shown in Fig. 1C, the electronic device 100 at least includes a display screen 14, a housing 40, and an internal structure 30 housed in a housing cavity enclosed by the display screen 14 and the housing 40.

[0074] Specifically, the housing 40 includes a middle frame 41 and a back cover 42. The middle frame 41 is connected to at least the edge of the back cover 42. The middle frame 41 includes a first middle frame 411 corresponding to the first body 11 and a second middle frame 412 corresponding to the second body 12. The back cover 42 includes a first back cover 421 corresponding to the first body 11 and a second back cover 422 corresponding to the second body 12. The first middle frame 411 and the first back cover 421 are connected to the second middle frame 412 and the second back cover 422 via the hinge 13.

[0075] Referring also to FIG. 1B , when the electronic device 100 is in a fully folded state, the first body 11 and the second body 12 overlap, so that the first middle frame 411 and the second middle frame 412 overlap, and the first back cover 421 and the second back cover 422 overlap. The antenna may be provided on the middle frame 41 and / or the back cover.

[0076] In this embodiment, the internal structure 30 includes, but is not limited to, a first circuit board assembly 311 and a first battery unit 312 corresponding to the first body 11, and a second circuit board assembly 321 and a second battery unit 322 corresponding to the second body 12. The first circuit board assembly 311 is used to house the electronic components contained in the first body 11, the second circuit board assembly 321 is used to house the electronic components contained in the second body 12, and the first battery unit 312 and the second battery unit 322 are used to power the electronic components disposed on the first body 11 and / or the second body 12. In another embodiment, the electronic device 100 may also include one battery unit or two or more battery units.

[0077] It will be understood that the electronic device 100 shown in FIG1C is merely an example of the electronic device, and the electronic device 100 may have more or fewer components than shown in FIG1C , may combine two or more components, or may have a different component configuration.

[0078] In the embodiment of the present application, the first antenna and the second antenna are both arranged on the first middle frame 411 corresponding to the first main body 11, and the first antenna and the second antenna are both arranged on the first metal frame 21, and one end of the first metal frame 21 is separated by the first gap G1 to form a first open end. The other end of the first metal frame 21 is separated by the second gap G2 to form a second open end. A second metal frame 22 is provided on the second middle frame 412 corresponding to the second main body 12, and one end of the first metal frame 21 is separated by the third gap G3 to form a third open end. The other end of the second metal frame 22 is separated by the fourth gap G4 to form a fourth open end. Both ends of the second metal frame 22 are open and not connected to the feeding point, forming a suspended structure, which can also be called a parasitic branch. In the embodiment of the present application, one end of the metal frame is open may refer to a structure in which one end of the metal frame is separated by a gap.

[0079] In the first embodiment, the first middle frame 411 can be made partially or entirely of metal material, and the first metal frame 21 constitutes a portion of the structure of the first middle frame 411. The second middle frame 412 can be made partially or entirely of metal material, and the second metal frame 22 constitutes a portion of the structure of the second middle frame 412.

[0080] Optionally, in other embodiments, the first middle frame 411 may be partially or entirely made of non-conductive material (such as glass or plastic, etc.), the first metal frame 21 is attached to the inner side of the first middle frame 411, and the second metal frame 22 is attached to the inner side of the second middle frame 412.

[0081] Alternatively, in other embodiments, the first back cover 421 may be made of a metal material, the first metal frame 21 constitutes a portion of the first back cover 421, and the second metal frame 22 constitutes a portion of the second back cover 422. For example, the first metal frame 21 and the second metal frame 22 may be separated metal accessories obtained by cutting a slit in the first back cover 421.

[0082] Example 1:

[0083] Figures 2A and 2B are schematic diagrams of antenna systems for a foldable electronic device according to an embodiment of the present application. Figure 2A shows the antenna system when the electronic device is in a folded state, and Figure 2B shows the antenna system when the electronic device is in an unfolded state.

[0084] As shown in Figure 2A, at this point, the hinge 13 folds the first body 11 and the second body 12, and the electronic device is in a folded state. To clearly present the antenna system structure of the first antenna, the second antenna, and the second metal frame, the projections of the first and second bodies on the plane where the first body is located are staggered (the actual projections completely overlap, and the second body 12 will obscure the antenna system structure of the first body). The first body 11 includes a first metal frame, and the second body 12 includes a second metal frame.

[0085] The first metal frame is open at both ends, including a first open end and a second open end. The first metal frame forms a strip conductor through the gap G1 and the gap G2. The first metal frame includes a first section and a second section, the first section is a section from the first open end to the grounding point 1, and the second section is a section from the second open end to the grounding point 2. The first metal frame can be provided with a grounding point 1 and a feeding point 1 of the first antenna, and a grounding point 2 and a feeding point 2 of the second antenna. There is a gap G1 between the first open end of the first section of the first metal frame and the middle frame (main screen frame) of the first body, and there is a gap G2 between the second open end of the second section of the first metal frame and the middle frame (main screen frame) of the first body.

[0086] The distance from ground point 1 to the first open end is less than 1 / 4 of the first operating wavelength. The distance from ground point 2 to the second open end is less than 1 / 4 of the second operating wavelength. The first operating wavelength is the wavelength of the signal radiated by the first antenna, and the second operating wavelength is the wavelength of the signal radiated by the second antenna. Operation refers to the state in which the antenna generates a radiated signal during power feeding.

[0087] Among them, the distance from grounding point 1 to the first open end is smaller than the distance from grounding point 2 to the first open end; the distance from grounding point 2 to the second open end is smaller than the distance from grounding point 1 to the second open end.

[0088] In an optional embodiment, the frequency band of the signal radiated by the first antenna and the frequency band of the signal radiated by the second antenna are at least partially the same. The first antenna and the second antenna can both operate in the cellular frequency band (MHB). For example, the first antenna and the second antenna both operate in the B3 frequency band (1.71-1.88 GHz). The first antenna and the second antenna can also operate in other frequency bands. For example, the first antenna operates in the communication frequency band of the Global Positioning System (GPS) and the second antenna operates in the B3 frequency band. For another example, the first antenna operates in the WiFi frequency band and the second antenna operates in the B40 (2.3-2.4 GHz) frequency band. As described above, since the operating frequency bands of the two antennas are at least partially the same, interference will occur between the first antenna and the second antenna.

[0089] When the electronic device is in the folded state, the first metal frame and the second metal frame are very close in the Z-axis direction (the thickness direction of the electronic device). As shown in Figure 1B, the plane containing the first metal frame and the plane containing the second metal frame can be the same plane. The distance between the first metal frame and the second metal frame in the thickness direction is a first distance, which can be 0-20mm. In this way, the second metal frame can further radiate the antenna signal of the first metal frame, thereby improving radiation performance.

[0090] The second metal frame is open at both ends, including a third open end and a fourth open end. There is a gap G3 between the second metal frame and the middle frame (secondary screen frame) of the second main body 12, forming a third open end; there is a gap G4 between the second metal frame and the middle frame (secondary screen frame) of the second main body 12, forming a fourth open end. The second metal frame is not connected to the feed source. The length of the second metal frame is greater than 1 / 2 of the first wavelength, and the first wavelength is the maximum value between the first working wavelength and the second working wavelength. The second metal frame can be a parasitic structure.

[0091] The oblique pattern portion in Figures 2A and 2B represents a reference ground, for example, a printed circuit board (PCB) floor, wherein the first body 11 may include a first reference ground, and the second body 12 may include a second reference ground. The black filled portion represents a metal frame, for example, a first metal frame and a second metal frame. The blank pattern portion represents a slot / slit / hollowing. The hollow interior is formed between the metal frame and the reference ground, that is, the hollow formed between the suspended metal frame and the reference ground, so that the radiating branches can be suspended on the ground to form a clearance. The gaps on the metal frame and the hollow inside can be filled with an insulating medium. In addition, the feeding point can be connected to the feed source.

[0092] The radiating branches of the two antennas corresponding to the first metal frame can be left-handed antennas or inverted F-shaped antennas (IFA), etc. For example, the first antenna and the second antenna are left-handed antennas to cover the cellular frequency band (MHB, generally operating in the 1.6-2.8 GHz range).

[0093] The second metal frame may be a metal microstrip disk antenna (MDA) or a flexible printed circuit (FPC) antenna, and this application does not limit this.

[0094] It should be noted that the first body and the second body may also include other types of antennas, which are not limited in this application.

[0095] In addition, regarding the overlapping projections of the metal frames of the electronic device when it is in the folded state, please refer to the relevant descriptions in Figures 1A and 1B above, and no further details will be given.

[0096] 2A and 2B , the antenna radiation conditions in the folded state and the unfolded state are described respectively.

[0097] Figures 3A to 5C illustrate the antenna structure and performance in the unfolded state:

[0098] Figures 3A to 3C are schematic diagrams of the structure of a deployed antenna system, exemplarily illustrating an embodiment of the present application. In Figures 3A to 3C, the radiating branches of the first antenna ANT1 and the second antenna ANT are both located on the first metal frame. The two grounding points of the first metal frame block the radiated signals of the two antennas, thereby improving the isolation between the two antennas.

[0099] As shown in Figures 3A to 3C, a gap S1 is formed between the first section of the first metal frame and the first reference ground, and a gap S2 is formed between the second section of the first metal frame and the first reference ground, forming a clearance. The radiating branches of the first antenna ANT1 and the second antenna ANT2 each have two ports Port. Among them, the first section of the first metal frame may include two interfaces Port1 and Port2, Port1 can be connected to one end of the first feed source 311, and the other end of the first feed source 311 is grounded; the second section of the first metal frame may include two interfaces Port3 and Port4; Port4 is connected to one end of the second feed source 314, and the other end of the second feed source 314 is grounded. In the first metal frame, the ports from one end to the other are Port1, Port2, Port3 and Port4 in sequence. Among them, Port1 and Port4 are respectively located on both sides of the first metal frame close to the two open ends, and Port2 and Port3 are respectively located in the middle of the first metal frame away from the two open ends. The specific positional relationship among Port1, Port2, Port3 and Port4 can be referred to in turn with reference to the positional relationship among feeding point 1, grounding point 1, grounding point 2 and feeding point 2 in FIG. 2A and FIG. 2B , which will not be described in detail.

[0100] In the first metal frame, Port 2 and Port 3 need to be grounded (grounded ports). For the above structure, Figures 3A to 3C provide three different grounding solutions:

[0101] Grounding Option 1: Direct Grounding:

[0102] As shown in FIG3A , Port 2 is directly grounded, and Port 3 is directly grounded. In this case, Port 2 and Port 3 of the two antennas need to be grounded to form a barrier.

[0103] Grounding solution 2: Grounding through capacitors:

[0104] As shown in Figure 3B , Port 2 is grounded via capacitor 312, and Port 3 is grounded via capacitor 313. The addition of capacitors creates LC resonance, improving the isolation between the first antenna ANT1 and the second antenna ANT2 when deployed. When the distance between Port 2 and Port 3 is long, using capacitors to block them can achieve better isolation.

[0105] For example, when the capacitor 312 is 6pF and the capacitor 313 is 15pF, when the first antenna ANT1 and / or the second antenna ANT2 operates within the communication frequency band of B3 (1.71-1.88GHz), a 1.1-1.3GHz LC resonance can be generated between Port2 and Port3 of the first metal frame. After the LC resonance is generated, the isolation between the two antennas can be improved. The selection of the capacitance parameters is related to the distance between Port2 and Port3 and the communication frequency band, etc. Therefore, the capacitance parameters need to be flexibly adjusted and are not limited. Among them, operation refers to the state in which the antenna generates a radiation signal during the feeding process.

[0106] Grounding solution 3: Grounding through inductance and capacitance:

[0107] As shown in Figure 3C , Port 2 is coupled to one end of inductor 321, the other end of inductor 321 is coupled to one end of capacitor 322, and the other end of capacitor 322 is grounded. Similarly, Port 3 is coupled to one end of inductor 331, the other end of inductor 331 is coupled to one end of capacitor 332, and the other end of capacitor 332 is grounded. The connection between Port 2 and Port 3 on the first metal frame creates an LC connection, effectively increasing the ground distance between the first antenna ANT1 and the second antenna ANT2. This improves the isolation between the two antennas when Port 2 and Port 3 are close together.

[0108] In addition, as shown in the grounding scheme of FIG3C , the positions of the inductor and the capacitor can be interchanged, and LC resonance can also be formed to improve isolation.

[0109] In grounding schemes 2 and 3, the first and second grounding points form an LC resonant structure. This LC resonant structure isolates the radiated signals from the first and second antennas, effectively decoupling them. The resonant frequency of the LC resonant structure is lower than the frequency of the radiated signals from the first and second antennas. For example, the operating frequency of the first and second antennas is 1.72 GHz, which is lower than the resonant frequency of the LC resonant structure's 1.3 GHz.

[0110] FIG4A is a schematic diagram of S-parameter curves of the first antenna and the second antenna when the electronic device is in the unfolded state. Reference numerals S11 and S22 respectively indicate reflection coefficient curves of the first antenna ANT1 and the second antenna ANT2, and reference numeral S12 indicates a transmission coefficient curve between the first antenna ANT1 and the second antenna ANT2.

[0111] As shown in FIG4A , the first antenna ANT1 and the second antenna ANT2 resonate in the B3 frequency band, and the isolation is approximately -8.5 dB.

[0112] FIG4B is a schematic diagram illustrating antenna efficiency curves for the first antenna and the second antenna of the electronic device when the electronic device is in the unfolded state. The symbols Systerm Rad.Efficiency[AC1]1 and Systerm Rad.Efficiency[AC1]2 are used to indicate the radiation efficiency curves of the first antenna ANT1 and the second antenna ANT2, respectively, and the symbols Systerm Tot.Efficiency[AC1]1 and Systerm Tot.Efficiency[AC1]2 are used to indicate the system efficiency curves of the first antenna ANT1 and the second antenna ANT2, respectively.

[0113] As shown in Figure 4B, in the B3 frequency band, the antenna efficiency of the first antenna and the second antenna is about -2dB. Since the ports Port2 and Port3 in Figure 3C are grounded through capacitors, the radiation efficiency curves of the first antenna ANT1 and the second antenna ANT2 can be seen to resonate (generate LC) in the frequency band of 1.1 to 1.3 GHz, causing the efficiency curve to sag downward, and there is a local minimum value of the antenna efficiency, thereby improving the isolation between the two antennas in the deployed state. Among them, the efficiency pit refers to the situation where the radiation efficiency of the antenna first decreases and then increases in a local range, forming a specific minimum efficiency. Of course, the closer the pit frequency formed by the LC is to the frequency of antenna resonance, the higher the isolation between the two antennas, but the antenna efficiency will be slightly reduced.

[0114] 5A to 5C are schematic diagrams showing current flows in the first metal frame in FIG. 3B at different frequencies.

[0115] Figure 5A is a schematic diagram of the current flow direction of the first metal frame when the operating frequency of the first antenna ANT1 is 1.7 GHz. In Figure 5A, in the first section of the first metal frame, Port2 is connected to the first grounding point, and the current direction is from feed point 1 to Port2 back to the ground. In the second section of the first metal frame, Port3 is connected to the second grounding point, and the current direction is from feed point 2 to Port3 back to the ground. In addition, the current between Port3 and Port2 also flows through Port3 to Port2 and back to the ground. Figure 5A shows that the feed point 1 of the first antenna is fed to generate a radiation signal, and the feed point 2 of the second antenna is not fed, and the current from feed point 1 to port2 is stronger.

[0116] Figure 5B is a schematic diagram showing the current flow in the first metal frame when the second antenna ANT2 operates at a frequency of 1.7 GHz. Unlike Figure 5A, feed point 1 of the first antenna is not fed, while feed point 2 of the second antenna is fed to generate a radiated signal. Therefore, the current from feed point 2 to port 3 is stronger.

[0117] Figure 5C is a schematic diagram of the current flow in the first metal frame when the operating frequency of the first antenna ANT1 is between 1.7 and 2.7 GHz. In Figure 5C, feed point 1 of the first antenna is fed to generate a radiated signal, while feed point 2 of the second antenna is not fed. This generates an LC resonance in the 1 GHz to 1.3 GHz frequency band between Port 2 and Port 3, causing the current to form a stop band (forming a loop between Port 2 and Port 3). The current in Port 3 can return to ground through Port 2 and cannot flow to feed point 1, isolating the current between the two antennas and improving isolation.

[0118] Of course, if the feeding point 2 of the second antenna is fed to generate a radiation signal and the feeding point 1 of the first antenna is not fed, the current flow diagram formed is mirror-symmetrical to the current flow diagram of Figure 5C, and LC will also be generated between Port 2 and Port 3, but the current direction is opposite, which will not be repeated.

[0119] Figures 6 to 9D illustrate the antenna structure and performance in the folded state:

[0120] Figure 6 is a schematic diagram of an antenna structure in a folded state exemplarily shown in an embodiment of the present application. As shown in Figure 6, the radiators (first metal frame) of the two antennas of the first body are placed parallel to the suspended structure (second metal frame) of the second body, that is, the sub-screen frame constructs a suspended structure. Among them, the structure of the first metal frame in the folded state is the same as that in the unfolded state. The description of Port2 and Port3 can refer to the relevant description of Figures 3A to 3C, and Port1 and Port4 can refer to Figures 3A to 3C, as well as the relevant description of Figure 7, which will not be repeated. In conjunction with the folding state of Figure 2A, the description of the first metal frame and the second metal frame can refer to the relevant description in Figures 2A and 2B, as well as Figures 1A to 1C, which will not be repeated.

[0121] Unlike the unfolded state, when the electronic device is in the folded state, during the feeding process of the first antenna and / or the second antenna of the first metal frame, the radiation signal of the first antenna and / or the second antenna can be further radiated in the second metal frame, which can improve the radiation efficiency of the two antennas on the first metal frame. The gaps G3 and G4 formed by the second metal frame can refer to the relevant descriptions in Figures 2A and 2B and are not repeated here. The second metal frame is provided with a port Port5, and Port5 can be connected to a frequency modulation circuit. The frequency modulation circuit of Port5 can modulate the frequency based on the working frequency bands of the two antennas, so that the signal radiation frequency band of the second metal frame can be adapted to the current communication frequency band of the first antenna and / or the second antenna, so as to improve the efficiency of the first antenna ANT1 and the second antenna ANT2.

[0122] Fig. 7 is a schematic diagram of an exemplary circuit structure of the antenna system in Fig. 6. As shown in Fig. 7, Port 1 of the first antenna ANT1 and Port 4 of the second antenna ANT2 can be connected to a frequency modulation circuit in addition to being connected to a feeding point.

[0123] In an embodiment of the present application, the frequency modulation circuit may include at least one switch (for example, a single-pole multi-throw switch) and a number of capacitors and / or inductors. One end of the switch is connected to a port of the first metal frame or the second metal frame, and multiple selection ends of the switch are connected to one end of each capacitor and / or inductor, and the other end of each capacitor and / or inductor is grounded. In this way, the switch can select one of the capacitors or inductors to be connected, which is used to adjust the electrical length in the antenna communication to adjust the operating frequency and improve the flexibility and adaptability of the antenna communication. Of course, the specific structure of the frequency modulation circuit can be adjusted, for example, the linkage control of multiple switches selects capacitors or inductors. For another example, one of the selection ends of the switch can be directly grounded. The switch can be a metal shrapnel.

[0124] Specifically, the first section of the first metal frame is connected to the first frequency modulation circuit, which is used to adjust the operating frequency of the first antenna to the first frequency. Port1 can be connected to a feeding point and a frequency modulation circuit. Port1 can be connected to one end of the capacitor 711 and one end of the switch 3 (713), the other end of the capacitor 711 is connected to one end of the first feeding point 712, and the other end of the first feeding point 712 is grounded. (The first frequency modulation circuit includes switch 3 and K capacitive inductive devices) The K selection ports of switch 3 (713) are connected to one end of each capacitor or inductor 714 in turn, and the other end of each capacitor or inductor 714 is grounded. Each capacitor or inductor 714 includes K capacitive inductive devices, K is an integer greater than 2, and the parameters of each capacitor or inductor should be different.

[0125] Correspondingly, the second section of the first metal frame is connected to the second frequency modulation circuit, which is used to adjust the operating frequency of the second antenna to the second frequency. Port4 can connect a feeding point and a frequency modulation circuit. Port4 can connect one end of the capacitor 741 and one end of the switch 4 (743) (the second frequency modulation circuit includes switch 4 and M capacitive inductive devices), the other end of the capacitor 741 is connected to one end of the second feeding point 742, and the other end of the second feeding point 742 is grounded. The M selection ports of switch 4 (743) are connected to one end of each capacitor or inductor 744 in turn, and the other end of each capacitor or inductor 744 is grounded. Each capacitor or inductor 744 includes M capacitive inductive devices, M is an integer greater than 2, and the parameters of each capacitor or inductor should be different. In the embodiment of the present application, for ease of understanding, the circuit structure of the first antenna ANT1 and the second antenna ANT2 can be roughly regarded as a centrally symmetrical structure.

[0126] Optionally, a feeding point and a frequency modulation circuit (Port 1 and Port 4) can also be connected through different ports. For example, the first section of the first metal frame also includes Port 9. The electronic device can connect the first frequency modulation circuit to Port 9, and the first feeding point 712 to Port 1. In addition, the circuit connecting the metal frame to the feeding point is not connected through a capacitor. For example, Port 1 is directly connected to the first feeding point 712. This application is not limited to the above situation.

[0127] The second metal frame is connected to the third frequency modulation circuit, which is used to adjust the frequency of the second metal frame to the third frequency. Port 5 of the second metal frame can also be connected to the third frequency modulation circuit. Port 5 can be connected to one end of switch 1 (752) (the third frequency modulation circuit includes switch 1 and N capacitive inductors), and the N selection ends of switch 1 (752) can be connected to one end of each capacitor or inductor 751, and the other end of each capacitor or inductor 751 is grounded. N is also an integer greater than 2. Switch 1 (752) can be used to select capacitors or inductors of different specifications for grounding to adapt to the appropriate frequency band and electrical length. During the selection process of switch 1, the inductor shortens the electrical length and the capacitor increases the electrical length. The size of the electrical length shortened and increased by the inductor is related to the size of the device parameters. LC will cause the antenna efficiency to be slightly reduced. The appropriate capacitor or inductor can be selected according to the isolation and efficiency standards. Among them, switch 1 can be a metal spring for selecting the communication frequency band. For example, switch 1 can adjust a total of 8 states, each state corresponding to a different communication frequency band, such as B0, B3, B1, B41, etc.

[0128] The grounding scheme for Port 2 and Port 3 can refer to the description in FIG3B . Port 2 of the first antenna ANT1 can be connected to one end of capacitor 721, and the other end of capacitor 721 can be grounded. Port 3 of the second antenna ANT2 can be connected to one end of capacitor 731, and the other end of capacitor 731 can be grounded. In addition, the grounding scheme for Port 2 and Port 3 can also be the schemes in FIG3A and FIG3C , which are not limited in this application.

[0129] After selecting switches 1, 3, and 4, the first and second antennas can determine the corresponding frequency bands for communication. For example, if the current communication frequency is B3, the connected capacitor and inductor parameters are as follows: capacitor 714 is 0.3pF; capacitor 711 is 0.4pF; capacitor 721 is 6pF; capacitor 731 is 15pF; inductor 744 is 20nH; and capacitor 741 is 0.5pF. If one of the capacitors or inductors 751 is 39nH, when switch 1 selects this capacitor, Port 5 of the second metal frame is connected to ground via the 39nH capacitor.

[0130] Combined with the antenna structure shown in Figure 7, the method of improving antenna efficiency is described:

[0131] The electronic device adjusts the operating frequency of the first antenna by adjusting the first frequency modulation circuit. Different devices are connected to the multiple selection ends of the switch in the first frequency modulation circuit, and the corresponding radiation frequencies of the first antenna are different. The electronic device can store a first mapping relationship between the switch options and frequencies in the first frequency modulation circuit. When the electronic device determines that the first antenna needs to communicate at the first frequency, the electronic device can select the corresponding switch option from the first mapping relationship as the target switch option based on the first frequency. The electronic device can control the open-loop adjustment of the first frequency modulation circuit to the target switch option. At this point, the electronic device adjusts the operating frequency of the first antenna to the first frequency by adjusting the first frequency modulation circuit.

[0132] Referring to the above-mentioned method of adjusting the operating frequency of the first antenna, the electronic device can adjust the operating frequency of the second antenna to the second frequency by adjusting the second frequency modulation circuit. The electronic device can also adjust the radiation frequency of the second metal frame to the third frequency by adjusting the third frequency modulation circuit. It will not be repeated here.

[0133] Furthermore, before adjusting the radiation frequency of the second metal frame to the third frequency, the electronic device needs to first determine the third frequency. If the electronic device determines that the radiation efficiency of the first antenna needs to be improved, the third frequency is determined to be the operating frequency of the first antenna, that is, the third frequency is equal to the first frequency. If the electronic device determines that the radiation efficiency of the second antenna needs to be improved, the third frequency is determined to be the operating frequency of the second antenna, that is, the third frequency is equal to the second frequency.

[0134] FIG8A is a schematic diagram of the S-parameter curves of the first antenna and the second antenna when the electronic device is in a folded state. (Antenna system structure in FIG6 ) In which, the reference numerals S11 and S22 are used to indicate the reflection coefficient curves of the first antenna ANT1 and the second antenna ANT2, respectively. The reference numeral S12 is used to indicate the transmission coefficient curve between the first antenna ANT1 and the second antenna ANT2. As can be seen from the S12 curve, resonance occurs at around 1.7 GHz, with an isolation of -10 dB. In addition, the second metal frame generates a parasitic resonance behind the resonance of the first antenna ANT1 and the second antenna ANT2.

[0135] Figure 8B is a schematic diagram of antenna efficiency curves for the first and second antennas when the electronic device is in a folded state. (Antenna system structure in Figure 6) The labels Systerm Rad.Efficiency[AC1] and Systerm Rad.Efficiency[AC1]2 are used to indicate the radiation efficiency curves of the first antenna ANT1 and the second antenna unit ANT2, respectively, and the labels Systerm Tot.Efficiency[AC1] and Systerm Tot.Efficiency[AC1]2 are used to indicate the system efficiency curves of the first antenna ANT1 and the second antenna ANT2, respectively. It can be seen from the two radiation efficiency curves that the second metal frame produces a parasitic resonance between 1.8 and 2 GHz. This parasitic resonance is reflected in the efficiency curve as a minimum value between 1.8 and 2 GHz, which can improve the efficiency of the two antennas in the folded state and improve the isolation between the two antennas.

[0136] Based on the structures and simulation results of the unfolded and folded electronic devices, the following comparison can be made:

[0137] Table 1

[0138] Table 1 shows a comparison of antenna performance in the folded and unfolded states, as shown in Example 1 of the present application. The isolation is improved by 1.5 dB compared to the unfolded state, and the efficiency of the first antenna ANT1 in the folded state changes by 0.7 dB compared to the unfolded state. The efficiency of the second antenna ANT2 remains unchanged between the unfolded and folded states. Thus, by adding a suspension structure to the structural design, the isolation of the two antennas can be improved, and the efficiency of one of the antennas can be increased in the folded state. Therefore, the efficiency of the folded state is slightly lower than that of the unfolded state, while the isolation is improved.

[0139] 9A to 9D are schematic diagrams showing current flows in the first metal frame and the second metal frame at different frequencies (corresponding to the antenna system structure in FIG. 6 ).

[0140] FIG9A is a schematic diagram of the current flow of the first metal frame and the second metal frame when the operating frequency of the first antenna ANT1 is 1.78 GHz. Among them, the feeding point 2 of the second antenna is not fed, and the feeding point 1 of the first antenna is fed to generate a radiation signal. The current situation of the first metal frame can refer to the relevant description in FIG5A and will not be repeated. The direction of the current on the second metal frame is the same as the direction of the current from the feeding point 1 to the port 2, thereby enhancing the radiation efficiency of the first antenna in the first metal frame.

[0141] In Figure 9A , the electronic device is in a folded state. If the first antenna is fed to generate a radiated signal at the first operating frequency, the first metal frame generates a current 1 from feed point 1 to port 2 at the first operating frequency. During this process, the second metal frame couples the radiated signal from the first antenna at the first operating frequency band, generating a current 2 from the third open end to the fourth open end at the first operating frequency band. Current 1 and current 2 have the same direction.

[0142] Figure 9B is a schematic diagram of the current flow in the first and second metal frames when the operating frequency of the second antenna ANT2 is 1.72 GHz. Feed point 1 of the first antenna is not fed, while feed point 2 of the second antenna is fed to generate a radiated signal. The current flow in the first metal frame can be referred to the relevant description in Figure 5B and will not be repeated here. The direction of the current in the second metal frame is the same as the direction of the current from feed point 2 to port 3, thereby enhancing the radiation efficiency of the second antenna in the first metal frame.

[0143] In Figure 9B , the electronic device is in a folded state. If the second antenna feed generates a radiation signal at the second operating frequency, the first metal frame generates a current 3 at the second operating frequency, flowing from feed point 2 to port 3. In this process, the second metal frame couples the radiation signal at the second operating frequency band of the second antenna, generating a current 4 at the second operating frequency band, flowing from the fourth open end to the third open end. Current 3 and current 4 have the same direction.

[0144] Figure 9C shows the current flow in the first and second metal frames at 1.9 GHz when the operating frequency of the first antenna ANT1 is 1.78 GHz. Feed point 2 of the second antenna is unpowered, while feed point 1 of the first antenna is powered to generate a radiated signal. The current in the first metal frame flows to the right, while the current in the second metal frame flows to the left.

[0145] In Figure 9C , the first metal frame generates a current 5 at the fourth frequency (1.9 GHz) flowing from the first open end to the second open end. When the second metal frame is coupled to the first antenna, a current 6 at the fourth frequency flows from the fourth open end to the third open end. Current 5 and current 6 are in opposite directions, and the fourth frequency is greater than the first frequency (1.78 GHz). The fourth frequency may be the resonant frequency of the second metal frame itself.

[0146] Figure 9D shows the current flow through the first and second metal frames at 1.9 GHz when the operating frequency of the second antenna ANT2 is 1.72 GHz. Feed point 1 of the first antenna is unpowered, while feed point 2 of the second antenna is powered to generate a radiated signal. The current in the first metal frame flows to the left, while the current in the second metal frame flows to the right.

[0147] In Figure 9D, the first metal frame generates a current 7 in the direction from the second open end to the first open end at the fifth frequency (1.9GHz); when the second metal frame is coupled to the first antenna, the second metal frame generates a current 8 in the direction from the third open end to the fourth open end at the fifth frequency; the direction of current 7 is opposite to that of current 8, the fifth frequency is greater than the second frequency, and the fifth frequency is the resonant frequency of the second metal frame itself.

[0148] In Figures 9C and 9D, the currents of the first and second metal frames at a frequency of 1.9 GHz are currents outside the B3 band (outside the operating frequency bands of the first and second antennas). The currents of the second metal frame and the first metal frame flow in opposite directions and are equal in amplitude. Therefore, at 1.9 GHz, the energy of the signal radiated by the first and / or second antennas cancels out the energy of the signal radiated by the second metal frame. Combined with what is shown in Figure 8B, a local minimum in antenna efficiency occurs outside the B3 band (1.8-2 GHz), which can improve the efficiency and performance of the first and / or second antennas within the B3 band.

[0149] Example 2

[0150] In the first embodiment, the connection position of the second metal frame to the third frequency modulation circuit is not limited. The contents in Figures 10A to 13B illustrate the specific situations of connecting the third frequency modulation circuit at different positions on the second metal frame:

[0151] 10A and 10B are schematic diagrams of an antenna system of another set of foldable electronic devices 100 provided in an embodiment of the present application.

[0152] 10A shows an antenna system when the electronic device is in a folded state, and FIG. 10B shows an antenna system when the electronic device is in an unfolded state.

[0153] The antenna system in Figures 10A and 10B differs from that in Figures 2A to 8B above in that switch 2 in Figures 10A and 10B is disposed on a side of the second metal frame close to gap G4. Switch 1 in Figures 2A and 2B is disposed on a side of the second metal frame close to gap G3. In Figures 18A and 18B, the third frequency modulation circuit includes switch 2 and N capacitive inductors, which can be used to adjust the frequency of the second metal frame to a third frequency. The first metal frame, the second metal frame, and the corresponding connection and positional relationships in Figures 10A and 10B can be referred to the relevant contents of Figures 2A and 2B and will not be described in detail.

[0154] The radiation performance of the electronic device in the folded state will be described below with reference to FIG. 11 to FIG. 13B .

[0155] Figure 11 is a schematic diagram of the antenna structure of the electronic device in Figure 10A when folded. The descriptions of the first and second metal frames, G1, G2, G3, and G4, as well as Ports 1, 2, 3, and 4 in Figure 11 can be found in the descriptions of Figure 6 and are omitted. Furthermore, the location of Port 6 can be found in the descriptions of Switch 2 in Figures 10A and 10B and are omitted.

[0156] Figure 12 is a schematic diagram of the circuit structure of an antenna system exemplarily provided in an embodiment of the present application. As shown in Figure 12, the second metal frame can be connected to the third frequency modulation circuit through Port 6, and the third frequency modulation circuit includes a switch 2 and N capacitive inductive devices. One end of switch 2 (1252). Like switch 1 in Example 1, Port 6 can be connected to one end of switch 2 (1252), and the N selection ends of switch 2 (1252) can be connected to one end of each capacitor or inductor 1251, and the other end of each capacitor or inductor 2051 is grounded. In addition, the connection structure of Port 1 to Port 4 in Figure 12 can refer to the relevant description in Figure 7 and will not be repeated.

[0157] After selecting switch 2, switch 3 and switch 4, the first antenna and the second antenna can determine the corresponding frequency band for communication. For example, the current communication is the B3 frequency band, and the connected capacitor and inductor parameters are: capacitor 1214 is 0.3pF; capacitor 1211 is 0.4pF; capacitor 1221 is 6pF; capacitor 1231 is 15pF; inductor 1244 is 21nH; capacitor 1241 is 0.5pF, and inductor 1251 is 39nH.

[0158] FIG13A is a schematic diagram of S-parameter curves of the first antenna and the second antenna of the electronic device in the folded state. Reference numerals S11 and S22 respectively indicate the reflection coefficient curves of the first antenna ANT1 and the second antenna ANT2, and reference numeral S12 indicates the transmission coefficient curve between the first antenna ANT1 and the second antenna ANT2.

[0159] As shown in FIG13A , when the electronic device in FIG11 is in the folded state, the first antenna ANT1 and the second antenna ANT2 resonate in the B3 frequency band, and the isolation is about -10 dB, which is the same as the first embodiment ( FIG8A ), and can greatly improve the performance of the folded state.

[0160] FIG13B is a schematic diagram illustrating antenna efficiency curves for the first antenna and the second antenna of the electronic device when the electronic device is in the folded state. The symbols Systerm Rad.Efficiency[AC1]1 and Systerm Rad.Efficiency[AC1]2 are used to indicate the radiation efficiency curves of the first antenna ANT1 and the second antenna ANT2, respectively; and the symbols Systerm Tot.Efficiency[AC1]1 and Systerm Tot.Efficiency[AC1]2 are used to indicate the system efficiency curves of the first antenna ANT1 and the second antenna ANT2, respectively.

[0161] As shown in Figure 13B, within the B3 frequency band, the antenna efficiency of the first antenna and the second antenna is approximately -2.2dB. This is basically the same as the antenna efficiency of Example 1. In the two radiation efficiency curves of Example 2, the second metal frame also produces a parasitic resonance between 2.2 and 2.4 GHz. This parasitic resonance is reflected in the efficiency curve as a minimum value between 1.8 and 2 GHz, which can also improve the efficiency of the two antennas in the folded state and the isolation between the two antennas.

[0162] The radiation efficiency and isolation data of the second embodiment in the unfolded state and the folded state are compared:

[0163] Table 2

[0164] Table 2 is a comparison table of radiation efficiency and isolation data for Example 2 of the disclosed embodiment of the present application in the unfolded and folded states. As shown in Table 2, the efficiency of the first antenna in the folded state decreases by 0.4dB compared to the unfolded state, and the efficiency of the second antenna in the folded state increases by 0.5dB compared to the unfolded state. The isolation between the first antenna and the second antenna increases by 1.5dB. Therefore, the efficiency change is within 0.5dB, the isolation is improved by about 1.5dB, and the overall antenna performance is improved in the folded state.

[0165] In general, the antenna structures in Examples 1 and 2 can achieve good isolation between the ports of a multiple-input multiple-output (MIMO) antenna system, and have the characteristics of high efficiency, miniaturization, and simple structure. They can meet the performance requirements of antennas in the field of smart terminal communications, and are also conducive to application in miniaturized electronic devices with smaller clearances, and can improve the communication performance of electronic devices.

[0166] Example 3

[0167] Figures 14A to 14C are schematic diagrams of another set of antenna systems for foldable electronic devices provided in an embodiment of the present application. Figure 14A shows the antenna system when the electronic device is in a folded state, and Figure 14B shows the antenna system when the electronic device is in an unfolded state.

[0168] In the third embodiment shown in Figures 14A and 14B, the antenna system on the first body 11 is the same as the antenna structure in the first embodiment. The first metal frame in the first body 11 can refer to the description of Figures 2A, 6 and 7, which will not be repeated here. Similarly, the second metal frame is open at both ends, including a third open end and a fourth open end. There is a gap G5 between the third open end of the second metal frame and the middle frame (sub-screen frame) of the second body, and there is a gap G6 between the fourth open end of the second metal frame and the middle frame (sub-screen frame) of the second body. Different from the first embodiment, the second metal frame in the second body 12 is provided with a grounding branch (i.e., grounding point 3) and at least two frequency modulation circuits (corresponding to switch 5 and switch 6), and the two frequency modulation circuits can be respectively arranged on both sides of the grounding branch.

[0169] The number of FM circuits on both sides of the grounding branch of the second metal frame is not limited. As shown in Figure 14C, two FM circuits are provided on one side of the grounding branch (corresponding to switches 5 and 7), and one FM circuit is provided on the other side (corresponding to switch 6). Of course, there are other possible numbers of FM circuits on both sides of the grounding branch, and this embodiment of the application does not limit this.

[0170] Figure 15 is a schematic diagram of the antenna structure of the electronic device in Figure 14A when it is in a folded state, provided by an embodiment of the present application. As shown in Figure 15, the first metal frame in the first body 11 has the same structure as that in Example 1. For details, please refer to the description of the first body 11 in Figure 6, which will not be repeated here. In Figure 15, the same as in Example 1 is that the first metal frame is in the same position as the first. The second metal branch is also provided with two ports Port7 and Port8 and a ground branch. Among them, the Port7 port can be connected to a frequency modulation circuit, and the Port8 port can be connected to another frequency modulation circuit.

[0171] Figure 16 is a schematic diagram of the circuit structure of an antenna in the folded state of the electronic device shown in Figure 15, provided by an embodiment of the present application. As shown in Figure 16, Port 1 of the first antenna ANT1 and Port 4 of the second antenna ANT2 can be connected to a frequency modulation circuit in addition to a power supply. For a description of the frequency modulation circuit, refer to the description in Figure 7 and are omitted for brevity.

[0172] Specifically, Port 1 can be connected to a feed point and a frequency modulation circuit. Port 1 can be connected to one end of capacitor 1611 and one end of switch 3 (1613). The other end of capacitor 1611 is connected to one end of the first feed source 1612, and the other end of the first feed source 1612 is grounded. The K selection ports of switch 3 (1613) are sequentially connected to one end of each capacitor or inductor 1614, and the other end of each capacitor or inductor 1614 is grounded. Each capacitor or inductor 1614 includes K capacitive and inductive devices, where K is an integer greater than 2, and the parameters of each capacitor or inductor should be different.

[0173] Correspondingly, Port4 can also be connected to a feeding point and a frequency modulation circuit. Port4 can be connected to one end of capacitor 1641 and one end of switch 4 (1643), the other end of capacitor 1641 is connected to one end of the second feed power source 1642, and the other end of the second feed power source 1642 is grounded. The M selection ports of switch 4 (1643) are connected to one end of each capacitor or inductor 1644 in turn, and the other end of each capacitor or inductor 1644 is grounded. Each capacitor or inductor 1644 includes M capacitive and inductive devices, M is an integer greater than 2, and the parameters of each capacitor or inductor should be different. For details, please refer to the description of 7.

[0174] Port 7 and Port 8 of the second metal frame can be connected to a frequency modulation circuit respectively. Port 7 can be connected to one end of switch 5 (1652), and the N selection ends of switch 5 (1652) can be connected to one end of each capacitor or inductor 1651, and the other end of each capacitor or inductor 1651 is grounded. Port 8 can be connected to one end of switch 6 (1662), and the R selection ends of switch 6 (1662) can be connected to one end of each capacitor or inductor 1661, and the other end of each capacitor or inductor 1661 is grounded. N and R are also integers greater than 2. Switch 5 and switch 6 can also be used to select the grounding of capacitor or inductor modules of different specifications to adapt to the operating frequency of the corresponding antenna. For details, please refer to the relevant description of Figure 7 and will not be repeated here.

[0175] Similarly, the grounding scheme for Port 2 and Port 3 can also refer to the description in Figure 3B. Port 2 of the first antenna ANT1 can be connected to one end of capacitor 1621, and the other end of capacitor 1621 can be grounded. Port 3 of the second antenna ANT2 can be connected to one end of capacitor 1631, and the other end of capacitor 1631 can be grounded. In addition, the grounding scheme for Port 2 and Port 3 can also be the schemes in Figures 3A and 3C, which are not limited in this application.

[0176] After selecting switch 3, switch 4, switch 5 and switch 6, the first antenna and the second antenna can determine the corresponding frequency band for communication. For example, the current communication is the B3 frequency band, and the connected capacitor and inductor parameters are: capacitor 1614 is 0.4pF; capacitor 1611 is 0.4pF; capacitor 1621 is 6pF; capacitor 1631 is 15pF; inductor 1644 is 24nH; capacitor 1641 is 0.5pF; inductor 1651 is 56nH; and inductor 1661 is 15nH.

[0177] The second metal frame is provided with a third grounding point (corresponding to Port 9), and the third frequency modulation circuit includes a fourth frequency modulation circuit and a fifth frequency modulation circuit; the fourth frequency modulation circuit is provided on one side of the third grounding point, and the fifth frequency modulation circuit is provided on the other side of the third grounding point. The number of frequency modulation circuits of the fourth frequency modulation circuit and the fifth frequency modulation circuit can be greater than or equal to 1. The grounding method of the third grounding point can refer to the three possible methods shown in Figures 3A to 3C. In this case, Port 9 can be grounded via capacitor 1671.

[0178] Optionally, when the electronic device is in the folded state, the projection of the third grounding point on the plane where the first body is located is between the first grounding point and the second grounding point, that is, the projection of Port 9 on the plane where the first body is located is between Port 2 and Port 3.

[0179] Optionally, when the electronic device is in the folded state, the projection of the third grounding point on the plane where the first body is located overlaps with the first grounding point or the second grounding point, that is, the projection of Port 9 on the plane where the first body is located overlaps with Port 2 or Port 3.

[0180] In embodiment three, since the second metal frame includes a fourth frequency modulation circuit and a fifth frequency modulation circuit. The electronic device can adjust the fourth frequency modulation circuit based on the operating frequency of the first antenna. Specifically, the electronic device can determine that the operating frequency of the first antenna is the target operating frequency of the fourth frequency modulation circuit, and determine the switch option corresponding to the target operating frequency according to the mapping relationship between the frequency and the switch option in the fourth frequency modulation circuit, based on adjusting the fourth frequency modulation circuit to the selected switch option. Similarly, the electronic device can also adjust the fifth frequency modulation circuit based on the operating frequency of the second antenna. The method is the same as the method for adjusting the fourth frequency modulation circuit, which will not be repeated. In addition, the method for determining the target operating frequency can be specifically described with reference to the method for improving antenna efficiency in Figure 7, which will not be repeated.

[0181] At this time, the projection of the first section of the first metal frame on the first body at least partially overlaps with the third section of the second metal frame. The projection of the second section of the first metal frame on the first body at least partially overlaps with the fourth section of the second metal frame. The third section is the section of the second metal frame between the fourth frequency modulation circuit and the third grounding point; the fourth section is the section of the second metal frame between the fifth frequency modulation circuit and the third grounding point.

[0182] FIG17A is a schematic diagram of S-parameter curves of the first antenna and the second antenna of the electronic device in the folded state. Reference numerals S11 and S22 respectively indicate the reflection coefficient curves of the first antenna ANT1 and the second antenna ANT2, and reference numeral S12 indicates the transmission coefficient curve between the first antenna ANT1 and the second antenna ANT2.

[0183] As shown in FIG17A , when the electronic device is in the folded state, the first antenna ANT1 and the second antenna ANT2 resonate at the B3 frequency band, and the isolation is -12.7 dB.

[0184] FIG17B is a schematic diagram of antenna efficiency curves for the first antenna and the second antenna of the electronic device in the folded state. The symbols Systerm Rad.Efficiency[AC1]1 and Systerm Rad.Efficiency[AC1]2 are used to indicate the radiation efficiency curves of the first antenna ANT1 and the second antenna unit ANT2, respectively; and the symbols Systerm Tot.Efficiency[AC1]1 and Systerm Tot.Efficiency[AC1]2 are used to indicate the system efficiency curves of the first antenna ANT1 and the second antenna ANT2, respectively.

[0185] As shown in Figure 17B, within the B3 frequency band, the system efficiency of the first antenna is approximately -1.9dB, and the system efficiency of the second antenna is approximately -3dB. Therefore, in Example 3, a grounding point is added in the middle of the second metal frame. This design generates two parasitic resonances behind the desired resonance, resulting in two minimum values ​​between 1.9 and 2.2 GHz on the antenna efficiency curve. Example 3 provides better isolation and higher antenna performance.

[0186] Solution 1: No processing is performed on the position of the second body corresponding to the first metal frame in the first body.

[0187] Figures 18A and 18B are schematic diagrams of another set of antenna systems for a foldable electronic device 100 according to an embodiment of the present application. Figure 18A shows the antenna system when the electronic device is in a folded state, and Figure 18B shows the antenna system when the electronic device is in an unfolded state.

[0188] The first metal frame in the reference scheme 1 shown in Figures 18A and 18B has the same structure as the first metal frame in Example 1. The structure of the first metal frame can refer to the description of Figures 2A and 2B and will not be repeated here. In the second body 12, the position of the secondary screen frame corresponding to the first antenna and the second antenna in the first body 11 is not specially processed, that is, the overlapping area with the projection of the first metal frame in the first body on the plane where the second body is located (the same position where the second metal frame in Example 1 is located) is not specially processed, and the second middle frame is not subjected to slits and grooves. In Figure 18A, when the electronic device is in a folded state, the overlapping area of ​​the projection of the first metal frame in the first body on the plane where the second body is located is a complete metal frame and reference ground, which will block and interfere with the signal radiation of the first antenna and the second antenna, resulting in poor signal radiation effect.

[0189] FIG19A is a schematic diagram of S-parameter curves of the first antenna and the second antenna of the electronic device in the folded state. Reference numerals S11 and S22 respectively indicate the reflection coefficient curves of the first antenna ANT1 and the second antenna ANT2, and reference numeral S12 indicates the transmission coefficient curve between the first antenna ANT1 and the second antenna ANT2.

[0190] As shown in FIG19A , when the electronic device is in the folded state ( FIG18A ), the first antenna ANT1 and the second antenna ANT2 resonate in the B3 frequency band, and the isolation is about -4 dB. The isolation in embodiment 1 is about -8.5 dB, and the isolation between the two antennas in scheme 1 is even worse.

[0191] 19B is a schematic diagram of antenna efficiency curves of the first antenna and the second antenna when the electronic device is in the folded state, wherein the labels Systerm Tot. Efficiency [AC1] 1 and Systerm Tot. Efficiency [AC1] 2 are used to indicate the system efficiency curves of the first antenna ANT1 and the second antenna ANT2, respectively.

[0192] As shown in FIG19B , the system efficiency in the B3 frequency band is approximately -5 dB. Therefore, the solution of Example 1 (approximately -2 dB in FIG8B ) is about 3 dB more efficient than Solution 1.

[0193] After comparing implementation method 1 with all the solutions, the secondary screen frame corresponding to the two antennas of the main screen frame is not processed at this time. The performance of solution 1 is the worst, and the performance deteriorates a lot in the folded and unfolded states.

[0194] Solution 2: The second body corresponding to the first metal frame of the first body is completely hollowed out.

[0195] Figures 20A and 20B are schematic diagrams of another set of antenna systems for a foldable electronic device 100 according to an embodiment of the present application. Figure 20A shows the antenna system when the electronic device is in a folded state, and Figure 20B shows the antenna system when the electronic device is in an unfolded state.

[0196] The first metal frame in Scheme 2 shown in Figures 20A and 20B has the same structure as the first metal frame in Example 1. The first metal frame can refer to the description of Figure 2A and will not be repeated here. The position of the secondary screen frame corresponding to the first antenna and the second antenna in the first body 11 in the second body 12 (the same position as the second metal frame in Example 1) is completely hollowed out and is in a hollow shape. In Figure 20A, when the electronic device is in a folded state, the portion of the second body 12 that overlaps with the first antenna and the second antenna has no obstruction or overlapping reference ground and metal frame.

[0197] In addition, the descriptions of the first antenna, the second antenna, the reference ground, the metal frame, and the slots / slots / hollowings in Figures 18A and 18B, Figures 19A and 19B, and Figures 20A and 20B can all refer to the relevant descriptions in Figures 1A to 2B and are not repeated here.

[0198] FIG21A is a schematic diagram of S-parameter curves of the first antenna and the second antenna of the electronic device in the folded state. Reference numerals S11 and S22 respectively indicate the reflection coefficient curves of the first antenna ANT1 and the second antenna ANT2, and reference numeral S12 indicates the transmission coefficient curve between the first antenna ANT1 and the second antenna ANT2.

[0199] As shown in FIG21A , when the electronic device in FIG20A is in the folded state, the first antenna ANT1 and the second antenna ANT2 resonate at the B3 frequency band, and the isolation is about -8.5 dB, compared with the isolation of -10 dB in Example 1. The isolation of Example 1 is improved by 1.5 dB compared with Solution 2.

[0200] FIG21B is a schematic diagram of antenna efficiency curves for the first antenna and the second antenna of an electronic device provided in an embodiment of the present application when in a folded state. The symbols Systerm Rad.Efficiency[AC1]1 and Systerm Rad.Efficiency[AC1]2 are used to indicate the radiation efficiency curves of the first antenna ANT1 and the second antenna unit ANT2, respectively; and the symbols Systerm Tot.Efficiency[AC1]1 and Systerm Tot.Efficiency[AC1]2 are used to indicate the system efficiency curves of the first antenna ANT1 and the second antenna ANT2, respectively.

[0201] As shown in FIG. 21B , the efficiency in the B3 frequency band is approximately -2.5 dB. Therefore, the efficiency of the solution in Example 1 is comparable to that of Solution 2.

[0202] By comparing the radiation efficiency and isolation data of the folded embodiment 1, embodiment 3, and solutions 1 and 2:

[0203] Table 3

[0204] Table 3 is a comparison table of radiation efficiency and isolation data of the exemplary disclosed embodiments of the present application, namely, embodiment 1, embodiment 3, and solutions 1 and 2. As shown in Table 3, the antenna efficiency and isolation of solution 1 are the worst, and the antenna efficiency of solution 2 is comparable to that of embodiment 1, but the isolation of embodiment 1 is about 1.5dB higher than that of solution 2. The antenna efficiency of embodiment 3 is slightly higher than that of embodiment 1, and the isolation is about 2.7dB higher than that of embodiment 1, but the second metal frame in embodiment 3 needs to be connected to at least one more FM circuit. Therefore, in embodiment 1 of the present application, a second metal frame is constructed on the second body, and the second metal frame can serve as a parasitic for ANT1 and ANT2 at the same time, thereby improving the performance of the two antennas in multiple frequency bands on the first metal frame in the folded state. Compared with embodiment 1 and embodiment 3, the antenna performance of embodiment 1 is higher, the cost is lower, and the debugging is simpler; the second metal frame structure of embodiment 3 is more complex, the cost is higher, the debugging performance is more flexible, and the antenna efficiency and isolation are better.

[0205] In the present application, any one or more of the slot S1, slot S2, gap G1, gap G2, gap G3, gap G4, gap G5, and gap G6 may be filled with a non-conductive medium, for example, polycarbonate (PC). In practical applications, the widths of the slot S1, slot S2, gap G1, gap G2, gap G3, gap G4, gap G5, and gap G6 may be set according to actual conditions, and the embodiments of the present application do not impose any restrictions on this.

[0206] In this application, the wavelength in a certain wavelength mode of an antenna (such as a half-wavelength mode, a quarter-wavelength mode, etc.) may refer to the wavelength of the signal radiated by the antenna. For example, the half-wavelength mode of an antenna may produce resonance in the 2.4 GHz frequency band, wherein the wavelength in the half-wavelength mode refers to the wavelength of the signal radiated by the antenna in the 2.4 GHz frequency band. It should be understood that the wavelength of the radiated signal in air can be calculated as follows: wavelength = speed of light / frequency, where frequency is the frequency of the radiated signal. The wavelength of the radiated signal in a medium can be calculated as follows: wavelength = (speed of light / √ε) / frequency, where ε is the relative dielectric constant of the medium and frequency is the frequency of the radiated signal.

[0207] The above are only some of the embodiments of this application, and the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A foldable electronic device, characterized in that, The foldable electronic device includes a first body, a second body, and a rotating shaft. The first body and the second body are connected by the rotating shaft, and the foldable electronic device can be folded at the rotating shaft, where: The first body includes a first metal frame, and the first metal frame includes a first open end and a second open end; a first grounding point and a second grounding point are provided on the first metal frame; a first feeding point is provided between the first grounding point and the first open end, and a second feeding point is provided between the second grounding point and the second open end; The second body includes a second metal frame, and both ends of the second metal frame are open.

2. The foldable electronic device according to claim 1, wherein The second metal frame is a floating structure.

3. The foldable electronic device according to claim 1, wherein, When the foldable electronic device is in a folded state, the projection of the second metal frame on the plane where the first body is located overlaps at least partially with the first metal frame.

4. The foldable electronic device according to claim 2, wherein The at least partial overlap specifically includes: The projection of the second metal frame on the plane where the first body is located overlaps at least half in the length direction of the first section of the first metal frame; the first section of the first metal frame is the metal frame between the first open end and the first grounding point; or, The projection of the second metal frame on the plane where the first body is located overlaps at least half in the length direction of the second section of the first metal frame; the second section of the first metal frame is the metal frame between the second open end and the second grounding point.

5. The foldable electronic device according to claim 3 or 4, characterized in that, The at least partial overlap specifically includes: The projection of the second metal frame on the plane where the first body is located completely overlaps with the first metal frame.

6. The foldable electronic device according to any one of claims 3-5, characterized in that, The foldable electronic device further includes a first antenna and a second antenna provided on the first body; The first metal frame includes a first section and a second section. The first section of the first metal frame is the metal frame between the first open end and the first grounding point; the second section of the second metal frame is the metal frame between the second open end and the second grounding point; The first antenna includes the first section of the first metal frame; the second antenna includes the second section of the first metal frame.

7. The foldable electronic device according to claim 6, wherein, When the first antenna is fed at a first frequency, a first current in the direction from the first feeding point to the first grounding point is generated on the first metal frame at the first frequency; When the second metal frame couples with the first antenna, a second current in the direction from a third open end to a fourth open end is generated on the second metal frame at the first frequency; the direction of the first current is the same as that of the second current.

8. The foldable electronic device according to claim 7, wherein, A third current in the direction from the first open end to the second open end is generated on the first metal frame at a fourth frequency; A fourth current in the direction from the fourth open end to the third open end is generated on the second metal frame at the fourth frequency; the direction of the third current is opposite to that of the fourth current, and the fourth frequency is greater than the first frequency.

9. The foldable electronic device according to claim 6, wherein When the second antenna is fed at a second frequency, a fifth current is generated on the first metal frame at the second frequency in a direction from the second feeding point to the second grounding point; When the second metal frame couples the second antenna, a sixth current is generated on the second metal frame at the second frequency in a direction from the fourth open end to the third open end; the fifth current and the sixth current have the same direction.

10. The foldable electronic device according to claim 9, wherein, The first metal frame generates a seventh current at a fifth frequency in a direction from the second open end to the first open end; The second metal frame generates an eighth current at the fifth frequency in a direction from the third open end to the fourth open end; the seventh current and the eighth current have opposite directions, and the fifth frequency is greater than the second frequency.

11. The foldable electronic device according to any one of claims 6-10, characterized in that, The resonant frequency of the first antenna is a first frequency, and the resonant frequency of the second antenna is a second frequency. Both the first frequency and the second frequency fall within the range of the cellular frequency band.

12. The foldable electronic device according to claim 11, wherein The first frequency is the same as the second frequency.

13. The foldable electronic device according to any one of claims 1-12, characterized in that, The distance from the first grounding point to the first open end is less than the distance from the second grounding point to the first open end; the distance from the second grounding point to the second open end is less than the distance from the first grounding point to the second open end.

14. The foldable electronic device according to any one of claims 1-13, characterized in that, The length of the second metal frame is greater than or equal to 1 / 2 of the first wavelength, where the first wavelength is the maximum value of the first operating wavelength and the second operating wavelength. The first operating wavelength is the wavelength of the signal radiated by the first antenna, and the second operating wavelength is the wavelength of the signal radiated by the second antenna.

15. The foldable electronic device according to any one of claims 6-14, characterized in that, The first section of the first metal frame is connected to a first frequency modulation circuit for adjusting the resonant frequency of the first antenna to the first frequency; The second section of the first metal frame is connected to a second frequency modulation circuit for adjusting the resonant frequency of the second antenna to the second frequency; The second metal frame is connected to a third frequency modulation circuit for adjusting the resonant frequency of the second metal frame to a third frequency; The third frequency is the same as the first frequency, and / or the third frequency is the same as the second frequency.

16. The foldable electronic device according to claim 15, wherein The second metal frame is provided with a third grounding point. The third frequency modulation circuit includes a fourth frequency modulation circuit and a fifth frequency modulation circuit. The fourth frequency modulation circuit is disposed on one side of the third grounding point, and the fifth frequency modulation circuit is disposed on the other side of the third grounding point.

17. The foldable electronic device according to claim 16, wherein When the foldable electronic device is in a folded state, the projection of the third grounding point on the plane of the first main body is between the first grounding point and the second grounding point.

18. The foldable electronic device according to claim 16, wherein When the foldable electronic device is in a folded state, the projection of the third grounding point on the plane of the first main body overlaps with the first grounding point or the second grounding point.

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