Electronic device

Abstract

The application provides an electronic device, a first radiator includes a first coupling end; a second radiator includes a feeding end and a second coupling end arranged oppositely, and a first coupling gap is formed between the feeding end and the first coupling end; a third radiator includes a third coupling end, a first connecting point and a second grounding end, and a second coupling gap is formed between the third coupling end and the second coupling end; one end of a capacitive tuning circuit is electrically connected to the first connecting point, and the other end of the capacitive tuning circuit is grounded; a feed source is used for exciting the first radiator and the second radiator to form a first resonant mode supporting a first low-frequency frequency band, exciting the second radiator to form a second resonant mode supporting a second low-frequency frequency band, and exciting the third radiator and the capacitive tuning circuit to form a loop mode supporting a third low-frequency frequency band, and the resonant current of the loop mode is from the second grounding end to the first connecting point, the capacitive tuning circuit and the ground. The application provides an electronic device capable of improving antenna efficiency.

Description

Technical Field

[0001] This application relates to the field of communication technology, specifically to an electronic device. Background Technology

[0002] As the communication needs of electronic devices increase, these devices require more and more antennas. Improving antenna efficiency has become a technical problem that needs to be solved. Summary of the Invention

[0003] This application provides an electronic device that can improve antenna efficiency.

[0004] This application provides an electronic device, including an antenna assembly, the antenna assembly comprising:

[0005] The first radiator includes a first coupling end;

[0006] The second radiator includes a feed end and a second coupling end arranged opposite to each other, and a first coupling gap is formed between the feed end and the first coupling end;

[0007] The third radiator includes a third coupling end, a first connection point and a second grounding end, wherein a second coupling gap is formed between the third coupling end and the second coupling end;

[0008] A capacitive tuning circuit, one end of which is electrically connected to the first connection point, and the other end of which is grounded; and

[0009] The feed source is electrically connected to the feed terminal. The feed source is used to excite the first radiator and the second radiator to form a first resonant mode supporting a first low-frequency band. The feed source is also used to excite the second radiator to form a second resonant mode supporting a second low-frequency band. The feed source is also used to excite the third radiator and the capacitive tuning circuit to form a ring mode supporting a third low-frequency band. The resonant current of the ring mode is grounded from the second ground terminal through the first connection point and the capacitive tuning circuit. The center frequency of the first low-frequency band is less than the center frequency of the second low-frequency band, and the center frequency of the second low-frequency band is less than the center frequency of the third low-frequency band.

[0010] The electronic device provided in this application embodiment includes a first radiator comprising a first coupling terminal, a second radiator comprising a feed terminal and a second coupling terminal disposed opposite to each other, with a first coupling gap formed between the feed terminal and the first coupling terminal, and a third radiator comprising a third coupling terminal, a first connection point, and a second ground terminal, with a second coupling gap formed between the third coupling terminal and the second coupling terminal; one end of a capacitive tuning circuit is electrically connected to the first connection point, and the other end of the capacitive tuning circuit is grounded; a feed source is electrically connected to the feed terminal, and the feed source is used to excite the first radiator and the second radiator to form a first resonant mode supporting a first low-frequency band, and the feed source is also used to excite the second radiator. A second resonant mode supporting the second low-frequency band is formed. The feed source is also used to excite the third radiator and the capacitive tuning circuit to form a ring mode supporting the third low-frequency band. The resonant current of the ring mode goes to ground from the second ground terminal through the first connection point and the capacitive tuning circuit. The center frequency of the first low-frequency band is smaller than the center frequency of the second low-frequency band, and the center frequency of the second low-frequency band is smaller than the center frequency of the third low-frequency band. The first resonant mode is used to increase the bandwidth and efficiency of the second low-frequency band, and the ring mode is used to increase the efficiency of the second low-frequency band, thereby improving the efficiency of the second low-frequency band of the main mode (second resonant mode). Attached Figure Description

[0011] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly described below.

[0012] Figure 1 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application;

[0013] Figure 2 This is a partially exploded view of the electronic device provided in the embodiments of this application;

[0014] Figure 3 This is a partial rear view of the electronic device provided in the embodiments of this application;

[0015] Figure 4 This is a schematic diagram of the structure of an antenna assembly provided in an embodiment of this application;

[0016] Figure 5 This is a schematic diagram of the current distribution in the first resonant mode of the antenna assembly provided in the embodiments of this application;

[0017] Figure 6 This is a schematic diagram of the current distribution in the second resonant mode of the antenna assembly provided in the embodiments of this application;

[0018] Figure 7 This is a schematic diagram of the structure of the grounding terminal of the grounding circuit of the second radiator on the antenna assembly provided in this application embodiment being close to the corner point of the reference ground;

[0019] Figure 8This is a schematic diagram of the current distribution at the corner point of the grounding terminal of the grounding circuit of the second radiator on the antenna assembly provided in this application embodiment, which is close to the reference ground.

[0020] Figure 9 This is a schematic diagram of the current distribution in the third resonant mode of the antenna assembly provided in the embodiments of this application;

[0021] Figure 10 This is a schematic diagram of the capacitive tuning circuit including a capacitor element provided in the embodiments of this application;

[0022] Figure 11 This is a schematic diagram of the structure of the first radiator with the first coupling end being the ground end, provided in an embodiment of this application;

[0023] Figure 12 This is a schematic diagram of the structure of the first radiator including the first switching tuning circuit provided in the embodiments of this application;

[0024] Figure 13 This is a schematic diagram of the structure of the first radiator including the second switching tuning circuit provided in the embodiments of this application;

[0025] Figure 14 This is a schematic diagram of the structure of the first radiator including the third switching tuning circuit provided in the embodiments of this application;

[0026] Figure 15 This is a front view of an electronic device provided in this application embodiment, taking a candybar mobile phone as an example;

[0027] Figure 16 This is a schematic diagram of the structure of an electronic device provided in this application embodiment, which is a foldable phone with the hinge on the top.

[0028] Figure 17 This is a schematic diagram of the structure provided in the embodiments of this application, in which the first radiator is located in the first hand-held area, the second radiator is located in the free area, and the third radiator is located in the second hand-held area;

[0029] Figure 18 This is a schematic diagram of the structure of the electronic device provided in the embodiments of this application, which is a foldable electronic device;

[0030] Figure 19 These are the S-reference curve and efficiency curve of the electronic device provided in this application under folded free space;

[0031] Figure 20 These are the S-parameter curves and efficiency curves of the antenna assembly provided in this application;

[0032] Figure 21This application provides for setting a second radiator separately, setting a first radiator and a second radiator, setting a second radiator and a third radiator, and simultaneously setting the S-parameter curves of the first radiator, the second radiator and the third radiator;

[0033] Figure 22 The present application provides the efficiency curves for separately setting a second radiator, setting a first radiator and a second radiator, setting a second radiator and a third radiator, and simultaneously setting the first radiator, the second radiator and the third radiator.

[0034] Explanation of icon numbers:

[0035] Electronic device 1000; Antenna assembly 100; Display screen 200; Mid-frame 300; Back cover 400; Mid-plate 310; Frame 320; Top edge 321; Bottom edge 322; First side edge 323; Second side edge 324; Reference ground 500; First radiator 10; Second radiator 20; Third radiator 30; Capacitive tuning circuit 40; Feed source 50; First coupling terminal C; Feed terminal D; Second coupling terminal E; First coupling slot N1; Third coupling terminal F; First connection point G; Second grounding terminal H; Second coupling gap N2; Capacitive tuning circuit 40; Grounding circuit 60; First grounding terminal A; First side 501; Second side 502; Corner point 503; Inductor L0; First switch tuning circuit T1; First switch unit K1; First impedance tuning branch R1; Second switch tuning circuit T2; Second switch unit K2; Second impedance tuning branch R2; Third switch unit K3; Capacitor C0; First body 710; Second body 720. Detailed Implementation

[0036] The technical solution of this application will now be clearly and completely described with reference to the accompanying drawings. Obviously, the embodiments described in this application are only a part of the embodiments, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments provided in this application without creative effort are within the protection scope of this application.

[0037] In this application, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment to other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this application can be combined with other embodiments.

[0038] The terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a particular order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, an assembly or device comprising one or more components is not limited to the one or more components listed, but may optionally also include one or more components not listed but inherent to the exemplified product, or one or more components that it should have based on the described function.

[0039] Please see Figure 1 , Figure 1 This is a schematic diagram of the structure of an electronic device 1000 provided in an embodiment of this application. The electronic device 1000 includes, but is not limited to, devices with communication functions such as mobile phones, tablets, laptops, computers, wearable devices, drones, robots, and digital cameras. This embodiment uses a mobile phone as an example for illustration; other electronic devices can refer to this embodiment.

[0040] Please see Figure 2 , Figure 2 This is a partially exploded view of electronic device 1000. The electronic device 1000 includes the antenna assembly 100. Taking a mobile phone as an example, the working environment of the antenna assembly 100 is illustrated. The electronic device 1000 includes a display screen 200, a mid-frame 300, and a back cover 400 arranged sequentially along its thickness. The mid-frame 300 includes a mid-plate 310 and a frame 320 surrounding the mid-plate 310. The frame 320 may be a conductive frame. Of course, in other embodiments, the electronic device 1000 may not have a mid-plate 310. The display screen 200, mid-plate 310, and back cover 400 are stacked sequentially, forming receiving spaces between the display screen 200 and the mid-plate 310, and between the mid-plate 310 and the back cover 400, to accommodate components such as the motherboard, camera module, receiver module, battery, and various sensors. One side of the frame 320 surrounds the edge of the display screen 200, and the other side of the frame 320 surrounds the edge of the back cover 400, forming a complete appearance structure of the electronic device 1000. In this embodiment, the frame 320 and the middle plate 310 are an integral structure, while the frame 320 and the back cover 400 can be separate structures. The above describes the working environment of the antenna assembly 100 using a mobile phone as an example, but the antenna assembly 100 of this application is not limited to the above working environment.

[0041] Optionally, the electronic device 1000 is a non-foldable electronic device, such as a candybar mobile phone.

[0042] Optionally, the electronic device 1000 is a foldable electronic device, such as a foldable mobile phone.

[0043] Please see Figure 3 , Figure 3 The image shows a rear view of the electronic device 1000. The frame 320 includes a top edge 321 and a bottom edge 322 oppositely disposed, and a first side edge 323 and a second side edge 324 connecting the top edge 321 and the bottom edge 322. The top edge 321 is the side away from the ground when the user holds and uses the electronic device 1000 in portrait mode, and the bottom edge 322 is the side facing the ground when the user holds and uses the electronic device 1000 in portrait mode. The first side edge 323 is the left side when the user holds and uses the electronic device 1000 in portrait mode. The second side edge 324 is the right side when the user holds and uses the electronic device 1000 in portrait mode. Alternatively, the first side edge 323 can also be the right side when the user holds and uses the electronic device 1000. The second side edge 324 is the left side when the user holds and uses the electronic device 1000.

[0044] The specific structure of the antenna assembly 100 is illustrated below with reference to the accompanying drawings.

[0045] Please see Figure 3 and Figure 4 The electronic device 1000 further includes the antenna assembly 100 and the reference ground plane 500. The antenna assembly 100 includes a first radiator 10, a second radiator 20, a third radiator 30, a capacitive tuning circuit 40, and a feed 50.

[0046] Optionally, the reference ground 500 is disposed within the frame 320. The reference ground 500 is generally rectangular in shape. Because various slots, holes, etc., are formed on the reference ground edge of the reference ground 500 as needed to accommodate components or avoid other structures in the mobile phone. The reference ground 500 includes, but is not limited to, the metal alloy portion of the middle plate 310 and the reference ground metal portion of the circuit board (including the main board and sub-board). Generally speaking, the reference ground system in the electronic device 1000 can be equivalent to a roughly rectangular shape, hence the name reference ground 500. However, the term reference ground 500 does not imply that the reference ground is plate-shaped or a rectangular plate.

[0047] This application does not specifically limit the material of the first radiator 10. Optionally, the first radiator 10 may be made of a conductive material, including but not limited to conductive materials such as metals and alloys. This application does not specifically limit the shape of the first radiator 10. For example, the shape of the first radiator 10 may include, but is not limited to, strip-shaped, sheet-shaped, rod-shaped, coated, or thin-film-shaped. Figure 3The first radiator 10 shown is merely an example and does not limit the shape of the first radiator 10 provided in this application. In this embodiment, the first radiator 10 is always strip-shaped. This application does not limit the extension trajectory of the first radiator 10. Optionally, the first radiator 10 may extend along a straight line, a curve, or a bend. In other embodiments, the first radiator 10 may also extend along a bend or other trajectory. The first radiator 10 described above may be a line of uniform width along its extension trajectory, or it may be a strip of varying width, such as one with a gradually changing width or a widened region.

[0048] This application does not specifically limit the form of the first radiator 10. Optionally, the form of the first radiator 10 includes, but is not limited to, the metal frame 320, a metal frame embedded in the plastic frame 320, a metal radiator located within or on the surface of the frame 320, a flexible circuit board antenna formed on a flexible printed circuit board (FPC), a laser-directly formed antenna (LDS), a printed-directly formed antenna (PDS), a conductive sheet antenna (e.g., a metal bracket antenna), etc. In this embodiment, the first radiator 10 is taken as a part of the metal frame 320 of the electronic device 1000.

[0049] The material, shape, and form of the second radiator 20 and the third radiator 30 can be referenced from the material, shape, and form of the first radiator 10.

[0050] Please see Figure 3 and Figure 4 The first radiator 10 includes a first coupling end C. In other words, one end of the first radiator 10 is the first coupling end C. Optionally, the first coupling end C is a ground end or a free end. In this application, a ground end refers to the end electrically connected to the reference ground 500, and a free end refers to the end disconnected from other conductive parts on the frame 320 through an insulating gap. To ensure the structural strength of the frame 320 of the electronic device 1000, the aforementioned insulating gap is filled with insulating material.

[0051] Please see Figure 3 and Figure 4The second radiator 20 includes a feed end D and a second coupling end E arranged opposite to each other. In other words, the two ends of the second radiator 20 are the feed end D and the second coupling end E, respectively. Optionally, the feed end D is one end electrically connected to the feed source 50. The second coupling end E is a free end. A first coupling gap N1 is formed between the feed end D and the first coupling end C. Optionally, the first coupling gap N1 is an insulating gap, and the width of the first coupling gap N1 is 0.5 to 2 mm, but not limited to this size. The first radiator 10 and the second radiator 20 can be capacitively coupled through the first coupling gap N1. In one perspective, the first radiator 10 and the second radiator 20 can be regarded as two parts formed by the frame 320 being separated by the first coupling gap N1.

[0052] The first radiator 10 and the second radiator 20 are capacitively coupled through the first coupling gap N1. "Capacitive coupling" means that the first coupling gap N1 between the first radiator 10 and the second radiator 20 generates an electric field, allowing the signal from the first radiator 10 to be transmitted to the second radiator 20 through the electric field, and vice versa, so that electrical signals can be conducted between the first radiator 10 and the second radiator 20 even when they are not directly electrically connected.

[0053] Please see Figure 3 and Figure 4 The third radiator 30 includes a third coupling terminal F, a first connection point G, and a second grounding terminal H. A second coupling gap N2 is formed between the third coupling terminal F and the second coupling terminal E. Optionally, the second coupling gap N2 is an insulating gap, and its width is 0.5–2 mm, but not limited to this size. The second radiator 20 and the third radiator 30 can be capacitively coupled through the second coupling gap N2.

[0054] In other words, the two ends of the third radiator 30 are the second grounding terminal H and the third coupling terminal F, respectively, wherein the second grounding terminal H is the end electrically connected to the reference ground 500. The first connection point G can be the third coupling terminal F, or it can be the location between the third coupling terminal F and the second grounding terminal H.

[0055] Please see Figure 3 and Figure 4One end of the capacitive tuning circuit 40 is electrically connected to the first connection point G, and the other end of the capacitive tuning circuit 40 is grounded, which is equivalent to being electrically connected to the reference ground plane 500. The capacitive tuning circuit 40 is capacitive overall. The electrical length of the third radiator 30 is much smaller than the electrical length corresponding to the low-frequency band (i.e., 1 / 4 wavelength of the low-frequency band). The electrical length of the third radiator 30 cannot excite a low-frequency resonant mode. At this time, the third radiator 30 can be equivalent to an inductor. An equivalent LC resonant circuit is formed between the third radiator 30 and the capacitive tuning circuit 40, and the capacitive tuning circuit 40 is used to lower the resonant frequency of the equivalent LC resonant circuit to the low-frequency band.

[0056] The electrical length described in this application can satisfy the following formula:

[0057]

[0058] Where L is the physical length, a is the transmission time of the electrical or electromagnetic signal in the medium, and b is the transmission time in the free scene.

[0059] Please see Figure 4 The feed source 50 is electrically connected to the feed terminal D. That is, the second radiator 20 is the main radiator, the first radiator 10 is a parasitic radiator of the second radiator 20, and the third radiator 30 is a parasitic radiator of the second radiator 20. Optionally, the feed terminal D is also grounded through a grounding circuit 60.

[0060] The feed source 50 is used to excite the first radiator 10 and the second radiator 20 to form a first resonant mode supporting a first low-frequency band. That is, the feed source 50 transmits radio frequency signals to the first radiator 10 via the second radiator 20. Taking the first resonant mode as a 1 / 4 wavelength mode as an example, the electrical length of the first radiator 10 is 1 / 4 wavelength of the center frequency of the first low-frequency band. The first low-frequency band is less than 1 GHz.

[0061] The feed source 50 is also used to excite the second radiator 20 to form the second resonant mode supporting the second low-frequency band. Taking the second resonant mode as a 1 / 4 wavelength mode as an example, the electrical length of the second radiator 20 is 1 / 4 wavelength of the center frequency of the second low-frequency band. The second low-frequency band is less than 1 GHz.

[0062] The feed source 50 is also used to excite the third radiator 30 and the capacitive tuning circuit 40 (i.e., the equivalent LC resonant circuit) to form a ring mode supporting the third low-frequency band. The third low-frequency band is less than 1 GHz. Optionally, the electrical length of the third radiator 30 is much smaller than 1 / 4 wavelength of the third low-frequency band. Therefore, the ring mode formed in this application is not a characteristic resonance at the electrical length of the third radiator 30, but rather the resonance of an equivalent LC resonant circuit formed by the third radiator 30 being equivalent to an inductor and the capacitive tuning circuit 40 being equivalent to a capacitor. The center frequency of the third low-frequency band is the resonance point of this equivalent LC resonant circuit.

[0063] The resonant current in the ring mode flows from the second ground terminal H through the first connection point G and the capacitive tuning circuit 40 to ground. Due to the periodicity of the current, the resonant current in the ring mode can also flow in reverse.

[0064] The current intensity distribution of the resonant current in the ring mode is also different from that of the resonant current in the second resonant mode. For example, the resonant current in the second resonant mode has a current distribution from strong to weak, while the current intensity of the resonant current in the ring mode is relatively uniformly distributed on the third radiator 30.

[0065] The first, second, and third low-frequency bands are all less than 1 GHz. Optionally, the first, second, and third low-frequency bands are all greater than 0.65 GHz and less than 0.9 GHz. Further, the first, second, and third low-frequency bands can collectively cover the range of 0.65 GHz to 0.9 GHz.

[0066] Through the above design, this application forms three resonant modes through one antenna assembly 100 (one feed 50), and each resonant mode supports different frequency bands, thereby increasing the number of frequency bands that the antenna assembly 100 can support in the low-frequency band. For example, the antenna assembly 100 can support LB+LB+LB (low-frequency three-wave) or complex LB dual-wave applications.

[0067] Optionally, the coupling mode between the first radiator 10 and the second radiator 20 is HE mode. The center frequency of the first low-frequency band is lower than the center frequency of the second low-frequency band (the high-frequency side of the first low-frequency band). The first resonant mode is used to form an efficiency bulge in the second low-frequency band.

[0068] Specifically, when the first coupling end C is a free end, the first coupling end C is the point of strongest electric field, the feed end D is the point of strongest electric field, and the first resonant mode is the HE (magnetic field-electric field) mode between the first radiator 10 and the second radiator 20. The second resonant mode supported by the second radiator 20 is the main resonant mode. The first resonant mode formed by the coupling of the first radiator 10 and the second radiator 20 is a parasitic resonant mode. When the resonant point of the first resonant mode is located before the resonant point of the second resonant mode (low-frequency side), the first resonant mode can first form an efficiency dip and then an efficiency bulge after its resonant point (high-frequency side), that is, the first resonant mode is used to form an efficiency bulge on the low-frequency side of the second low-frequency band. Therefore, this application designs the first resonant mode formed by the coupling of the first radiator 10 and the second radiator 20, and designs the resonant point of the first resonant mode to be smaller than the resonant point of the second resonant mode, so that the first resonant mode formed by the first radiator 10 improves the efficiency of the second low-frequency band.

[0069] The center frequency of the second low-frequency band is smaller than that of the third low-frequency band. The ring module is used to form an efficiency protrusion in the second low-frequency band (the low-frequency side of the third low-frequency band).

[0070] The ring mode is integrated with the second resonant mode, and the resonant point of the ring mode is larger than the resonant point of the second low-frequency band. When the resonant point of the second resonant mode is located before the resonant point of the ring mode (on the low-frequency side), the ring mode can first form an efficiency dip and then an efficiency bulge before its resonant point (on the low-frequency side). The ring mode is used to form an efficiency bulge on the high-frequency side of the second low-frequency band. Therefore, this application designs the coupling mode between the third radiator 30 and the second radiator 20, and designs the resonant point of the ring mode to be larger than the resonant point of the second resonant mode, so that the ring mode formed by the third radiator 30 improves the efficiency of the second low-frequency band.

[0071] The electronic device 1000 provided in this application embodiment includes a first radiator 10 comprising a first coupling terminal C, a second radiator 20 comprising a feed terminal D and a second coupling terminal E disposed opposite to each other, with a first coupling gap N1 formed between the feed terminal D and the first coupling terminal C, a third radiator 30 comprising a third coupling terminal F, a first connection point G, and a second ground terminal H, with a second coupling gap N2 formed between the third coupling terminal F and the second coupling terminal E, one end of a capacitive tuning circuit 40 electrically connected to the first connection point G, and the other end of the capacitive tuning circuit 40 grounded, a feed source 50 electrically connected to the feed terminal D, the feed source 50 being used to excite the first radiator 10 to form a first resonant mode supporting a first low-frequency band, and the feed source 50 also being used to excite the second radiator 20. The radiator 20 forms the second resonant mode supporting the second low-frequency band. The feed source 50 is also used to excite the third radiator 30 and the capacitive tuning circuit 40 to form the ring mode supporting the third low-frequency band. The resonant current of the ring mode goes to ground from the second ground terminal H through the first connection point G and the capacitive tuning circuit 40. The center frequency of the first low-frequency band is less than the center frequency of the second low-frequency band, and the center frequency of the second low-frequency band is less than the center frequency of the third low-frequency band. The first resonant mode is used to increase the bandwidth and efficiency of the second low-frequency band, and the ring mode is used to increase the bandwidth and efficiency of the second low-frequency band. The first resonant mode and the ring mode form a dual efficiency-enhancing effect of the second resonant mode, thereby improving the efficiency of the second low-frequency band of the main mode (the second resonant mode).

[0072] Optionally, the third low-frequency band and the second low-frequency band form a continuous frequency band, and the ring mode is also used to increase the efficiency bandwidth of the second low-frequency band (to be explained in detail later) and improve the anti-frequency deviation characteristics.

[0073] Optional, please refer to Figure 4 The first radiator 10 further includes a first grounding terminal A disposed opposite to the first coupling terminal C. The first grounding terminal A is used for electrical connection to the reference floor 500.

[0074] Please see Figure 5 The current in the first resonant mode ( Figure 5 The dashed arrow portion (in the diagram) includes a first sub-current flowing from the first grounding terminal A to the first coupling terminal C, and a second sub-current flowing from the second coupling terminal E to the feed terminal D, and grounded at the feed terminal D. Due to the periodicity of the current, the current direction of the first resonant mode can be reversed. Optionally, the first sub-current is strong at the first grounding terminal A and weak at the first coupling terminal C, and the intensity of the first sub-current gradually decreases from the first grounding terminal A to the first coupling terminal C.

[0075] The intensity of the first sub-current is greater than the intensity of the second sub-current. In other words, the dominant current of the first resonant mode is located on the first radiator 10, while a small amount of current is present on the second radiator 20. The electrical length of the first radiator 10 is close to or equal to one-quarter wavelength of the center frequency of the first low-frequency band, so that the current mode of the first sub-current is one-quarter wavelength of the center frequency of the first low-frequency band. For example, the "close to" target value described in this application can be a range that differs from the target value by 1 / 10 of a wavelength.

[0076] Please see Figure 6 The current in the second resonant mode ( Figure 6 The dashed arrow (as shown in the diagram) indicates that the current flows from the second coupling terminal E to the feed terminal D. Due to the periodicity of the current, the current direction in the second resonant mode can be reversed. The current in the second resonant mode is strongest at the feed terminal D and weakest at the second coupling terminal E. The current intensity of the second resonant mode gradually decreases from the feed terminal D to the second coupling terminal E.

[0077] The electrical length of the current path in the second resonant mode is close to or equal to one-quarter of the wavelength of the center frequency of the second low-frequency band, so that the second resonant mode is a one-quarter wavelength mode of the center frequency of the second low-frequency band. The electrical length of the current path in the second resonant mode can be the electrical length of the second radiator 20, or the electrical length of the second radiator 20 plus the compensating inductor.

[0078] Please see Figure 7 The reference floor 500 includes a first side 501 and a second side 502 that are bent and connected. A corner point 503 is formed at the connection between the first side 501 and the second side 502. The first side 501 and the second side 502 may be perpendicular to each other. This application is not limited to the corner point 503 being the upper left corner, upper right corner, lower left corner, or lower right corner of the reference floor 500.

[0079] Optional, please refer to Figure 7The antenna assembly 100 further includes a grounding circuit 60. One end of the grounding circuit 60 is electrically connected to the feed terminal D, and the other end of the grounding circuit 60 is grounded, i.e., electrically connected to the reference ground 500. The distance between the grounding terminal of the grounding circuit 60 and the corner point 503 is less than or equal to 1 / 16 wavelength of the center frequency of the second low-frequency band. In other words, the return-to-ground position of the second radiator 20 is close to the corner point 503 of the reference ground 500, so that the reference ground 500 acts as a radiator, and the ground current formed by the second resonant mode on the reference ground 500 is canceled out as little as possible, thereby increasing the radiation efficiency of the second low-frequency band supported by the second resonant mode.

[0080] Specifically, regarding the reference ground plane 500 of the mobile phone, the length of its lateral side is similar to one-quarter of the wavelength of the low-frequency band. The reference ground plane 500 can be considered as an antenna element with a certain width. The reference ground plane 500 and the second radiator 20 form a feed-biased dipole antenna. In other words, the reference ground plane 500 can act as a radiator, generating a current distribution under the excitation of the feed source 50, thereby improving the radiation efficiency of the second low-frequency band.

[0081] Since the return position of the second radiator 20 is located near the corner point 503 of the reference floor 500, a floor current is formed on the reference floor 500 under the excitation of the feed source 50. The floor current includes a transverse current along the transverse side and a longitudinal current along the longitudinal side. The flow direction of the transverse current and the longitudinal current is towards the corner point 503. Since the transverse current and the longitudinal current intersect, or are even close to perpendicular, there is little mutual cancellation between the transverse current and the longitudinal current.

[0082] For details, please refer to Figure 8 Taking the first side 501 as the horizontal side and the second side 502 as the vertical side as an example, the length of the horizontal side is less than the length of the vertical side. When the antenna assembly 100 returns to ground at the corner point 503 of the reference ground 500, the maximum angle between the ground currents on the reference ground 500 is approximately 90°. That is, the horizontal current along the first side 501 and the vertical current along the second side 502 are the currents with the maximum angle, no reverse current is generated, and its far-field energy cancellation is small, improving the contribution efficiency of the reference ground 500, thereby enabling the first frequency band to have better radiation efficiency.

[0083] The second radiator 20 is disposed on the bottom edge 322 of the electronic device 1000, which can utilize the space on the bottom edge 322 of the electronic device 1000 and avoid the side position when holding the electronic device 1000 vertically, thereby having better working efficiency when holding the screen vertically.

[0084] In this embodiment, the distance between the grounding terminal of the grounding circuit 60 and the corner point 503 is designed to be less than or equal to 1 / 16 of the wavelength of the second low-frequency band. When the distance between the grounding terminal of the grounding circuit 60 and the corner point 503 is greater than 1 / 16 of the wavelength of the second low-frequency band, the portion of reverse current formed along the horizontal or vertical edge is relatively large. Thus, the portion of the reverse current canceling each other out is larger, resulting in lower radiation efficiency for the second low-frequency band. Therefore, when the distance between the grounding terminal of the grounding circuit 60 and the corner point 503 is less than or equal to 1 / 16 of the wavelength of the second low-frequency band, the portion of reverse current pairs formed along the horizontal or vertical edge is smaller, resulting in less impact on the efficiency of the second low-frequency band. Furthermore, the grounding terminal of the grounding circuit 60 can be located at the corner point 503, further reducing or eliminating the portion of reverse current formed along the horizontal or vertical edge, resulting in even less impact on the efficiency of the second low-frequency band.

[0085] In this embodiment, the distance between the grounding terminal of the grounding circuit 60 and the corner point 503 is less than or equal to 10mm.

[0086] As the communication requirements of the electronic device 1000 increase, more and more antennas need to be installed on it. These antennas occupy considerable space, especially low-frequency antennas, which are relatively large and take up a significant amount of space. Taking a mobile phone as an example, a single low-frequency antenna occupies the entire lower right corner of the device. To further improve the effective connection of low-frequency signals, multiple low-frequency antennas are used on the device, such as four. Because low-frequency antennas operate at low frequencies, each antenna requires an average stub length of 40-50mm in the overall device stack, occupying a considerable amount of space. If the length of the low-frequency antenna is shortened, the antenna radiation efficiency will decrease rapidly.

[0087] The following embodiments of this application will specifically describe the structure of the antenna assembly 100 that achieves miniaturization while ensuring antenna radiation efficiency.

[0088] Optionally, the electrical length of the second radiator 20 is less than 1 / 4 wavelength of the center frequency of the second low-frequency band.

[0089] Please see Figure 8 , Figure 8 This is a schematic diagram of the antenna assembly 100 provided in the first embodiment of this application. The grounding circuit 60 further includes an inductor L0. One end of the inductor L0 is electrically connected to the feed terminal D, and the other end of the inductor L0 is electrically connected to the reference ground plane 500. The inductor L0 is used to compensate for the electrical length of the second radiator 20.

[0090] Generally, the second radiator 20 needs to have an electrical length close to or equal to 1 / 4 wavelength of the center frequency of the second low-frequency band to facilitate the formation of a resonant mode supporting 1 / 4 wavelength of the second low-frequency band on the second radiator 20. However, due to the miniaturization of the second radiator 20 in this embodiment, the length of the second radiator 20 is shortened, and the electrical length of the second radiator 20 is less than or much less than 1 / 4 wavelength of the center frequency of the second low-frequency band.

[0091] The inductor L0 is used to compensate for the electrical length of the second radiator 20. The resonant current of the second resonant mode can flow from the second radiator 20 through the inductor L0 to the reference ground 500. The inductor L0 is used to increase the current path of the resonant current of the second resonant mode, compensate for the electrical length of the second radiator 20, and make the electrical length of the second radiator 20 and the inductor L0 close to 1 / 4 wavelength of the second low-frequency band, thereby providing the electrical length condition for the second radiator 20 to generate the second resonant mode.

[0092] In this embodiment, by placing the grounding position (the grounding terminal of the grounding circuit 60) of the second radiator 20 near the corner of the reference ground 500, the reference ground 500 can be excited to generate lateral and longitudinal currents, which participate in energy radiation, thereby improving the efficiency of the second low-frequency band. Furthermore, the lateral and longitudinal currents have less energy cancellation in the far field, thus also improving the efficiency of the second low-frequency band. Although shortening the length of the second radiator 20 will reduce the efficiency of the second resonant mode, the aforementioned design of this embodiment has already improved the efficiency of the second resonant mode to a good level. Even if the efficiency of the second radiator 20 decreases due to the shortened length, it still meets the usage standards. Therefore, this embodiment appropriately shortens the length of the second radiator 20 based on the above, ensuring the generation of the second resonant mode and relatively good efficiency, reducing the space occupied by the antenna assembly 100, and achieving miniaturization of the antenna assembly 100.

[0093] Furthermore, the length of the second radiator 20 is greater than or equal to 1 / 5 times the wavelength of 1 / 4 of the center frequency of the second low-frequency band. In this embodiment, the length of the second radiator 20 can be shortened to 1 / 2 times the wavelength of 1 / 4 of the center frequency of the second low-frequency band. In other words, the length of the second radiator 20 can be shortened to half its original size. Taking the second low-frequency band as an example, without shortening the length of the second radiator 20, the length of the second radiator 20 is approximately 50 mm. In this embodiment, the length of the second radiator 20 can be approximately 25 mm, which, while generating the second resonant mode, enables the second resonant mode to have relatively good radiation efficiency and achieves miniaturization of the antenna assembly 100. Furthermore, the length of the second radiator 20 can also be approximately 10 mm, which, while generating the second resonant mode, enables the second resonant mode to have relatively good radiation efficiency and further achieves miniaturization of the antenna assembly 100.

[0094] Optional, please refer to Figure 8 The inductor element L0 includes an inductor. One end of the inductor is electrically connected to the other end of the ground terminal of the grounding circuit 60, and the other end of the inductor is grounded. Thus, the resonant current of the second resonant mode can flow from the second radiator 20 and the inductor to ground. The sum of the equivalent electrical length of the inductor and the electrical length of the second radiator 20 is approximately one-quarter wavelength of the second low-frequency band, giving the antenna assembly 100 the electrical length conditions necessary to generate the second resonant mode.

[0095] Please see Figure 8 The antenna assembly 100 further includes a matching circuit M, which is electrically connected between the feed source 50 and the feed terminal D. The matching circuit M is used to tune the impedance matching between the feed source 50 port and the feed terminal D to form the second resonant mode. The matching circuit M includes at least one of a capacitor and an inductor.

[0096] It should be noted that even though the inductor can compensate for the reduction in electrical length caused by the shortening of the second radiator 20, the effect of the inductor on the resonant current is less than the radiation contribution of the radiating branch. Therefore, if the antenna assembly 100 is not positioned near the corner of the aforementioned reference ground 500, the efficiency of the second resonant mode will decrease. However, by positioning the antenna assembly 100 near the corner of the aforementioned reference ground 500, as described in this application, the efficiency reduction caused by the second resonant mode formed by the inductor and the second radiator 20 can be effectively compensated for. This achieves miniaturization of the antenna assembly 100 while also improving the efficiency of the second resonant mode.

[0097] Please see Figure 8Taking the first radiator 10 as a monopole antenna as an example, the monopole antenna is located on the right long side of the electronic device 1000 and near the bottom edge 322. The length of the second radiator 20 of the antenna assembly 100 is approximately 23 mm, which is about half the normal required size of the radiator of an LB antenna.

[0098] In this embodiment, the grounding point of the antenna assembly 100 (the grounding terminal of the grounding circuit 60 connected to the inductor is the grounding point) is located at a corner. This not only ensures that a resonant current in the LB low-frequency band is excited on the second radiator 20, but also ensures that a considerable portion of the energy of the antenna assembly 100 during low-frequency radiation comes from the radiation contribution of the reference ground plane 500 (e.g., a PCB board). The width of the short side (first side 501) of the reference ground plane 500 (e.g., a PCB board) is close to the length required for the LB low-frequency band, thus allowing it to replace more of the shortened second radiator 20 and excite the resonant current in the LB band. Furthermore, the strong current at the grounding point is distributed on the reference ground plane 500 (e.g., a PCB board) as follows... Figure 8 As shown, there is essentially no reverse current. The angle formed by the current on the reference ground 500 (e.g., a PCB board) is a maximum of 90 degrees, and the angle between the currents in other parts is even less than 90 degrees. The current on the reference ground 500 does not cancel out in the far-field energy. However, at other locations except corners, reverse current is generated on the reference ground 500 (e.g., a PCB board), and the current on the reference ground 500 cancels out in the far-field energy. Therefore, grounding the antenna assembly 100 at corners can significantly improve efficiency.

[0099] The above is a schematic diagram of the structure of the first radiator 10, with its grounding position located at the corner point 503 of the reference floor 500, and a miniaturized version of the first radiator 10. The specific structures of the third radiator 30 and the capacitive tuning circuit 40 are illustrated below.

[0100] In this embodiment, the electrical length of the third radiator 30 is less than 1 / 4 wavelength of the third low-frequency band and greater than 1 / 16 wavelength of the third low-frequency band.

[0101] The third radiator 30 serves as a parasitic radiator for the second radiator 20. The third radiator 30 requires an electrical length of approximately one-quarter of the low-frequency wavelength to generate an intrinsic resonant mode under the influence of the feed source 50. However, the electrical length of the third radiator 30 is much shorter than that of the second radiator 20, therefore, the electrical length of the third radiator 30 is insufficient to excite a low-frequency resonant mode.

[0102] Please see Figure 9The third radiator 30 is equivalent to an equivalent inductor with respect to the resonant current of the ring mode. The capacitive tuning circuit 40 and the third radiator 30 are equivalent LC circuits with respect to the resonant current of the ring mode. The electrical length of the third radiator 30 is less than 1 / 4 wavelength of the third low-frequency band. The third radiator 30 does not generate its intrinsic resonant mode; instead, it is equivalent to an inductor and, together with the capacitive tuning circuit 40, forms an equivalent LC resonant circuit. Given a fixed equivalent inductance, the capacitive tuning circuit 40 tunes the resonant frequency of the equivalent LC resonant circuit to a low frequency, which is denoted as the second low-frequency band.

[0103] In other words, the capacitive tuning circuit 40 is used to form an equivalent LC resonant circuit with the third radiator 30, and tunes the resonant point of the equivalent LC resonant circuit to a low-frequency band. The resonant frequency of the equivalent LC circuit is the center frequency of the third low-frequency band.

[0104] Thus, the equivalent LC resonant circuit formed by the third radiator 30 and the capacitive resonant circuit, the second radiator 20, and the third radiator 30, under the excitation of the feed source 50, form a three-wave resonance supporting low frequencies, improving low-frequency efficiency and bandwidth. In this embodiment, both the second radiator 20 and the third radiator 30 can be miniaturized and can support low-frequency three-wave resonance.

[0105] This application does not specifically limit the size of the third radiator 30. Optionally, the electrical length of the third radiator 30 is about 1 / 8 of the wavelength of the third low-frequency band, and the length of the third radiator 30 is 20mm ± 5mm.

[0106] If the length of the third radiator 30 is less than 15mm, it is too far from the physical resonant length (1 / 4 wavelength) of the third radiator 30. In this case, from the perspective of the S-parameters of the ring mode, the ring mode is weak, its contribution to the second resonant mode is small, and its effect on improving the efficiency of the first low frequency is small. In this application, the length of the third radiator 30 is designed to be close to 1 / 8 wavelength of the third low frequency band, realizing an extremely short low-frequency parasitic branch, forming a low-frequency three-wave. The ring mode is integrated with the second resonant mode, improving the radiation efficiency of the second resonant mode, and reducing the size occupied by the antenna assembly 100 while improving the low-frequency efficiency.

[0107] Please see Figure 10The capacitive tuning circuit 40 includes a capacitor element. The number of capacitor elements is at least one. Optionally, the capacitance value of the capacitor element is less than or equal to 10 pF. Taking the electrical length of the third radiator 30 as 1 / 8 wavelength of the third low-frequency band as an example, since the third radiator 30, with a length of approximately 1 / 8 wavelength of the third low-frequency band, can be equivalent to an inductor, for example, 10-20 nH. By setting the capacitive tuning circuit 40 as a capacitor element, the capacitor element and the third radiator 30 form an equivalent LC circuit. The capacitance value of the capacitor element is small, for example, less than 10 pF, to pull the resonant frequency of the equivalent LC resonant circuit down to the low-frequency band, thus forming the ring mode supporting the third low-frequency band.

[0108] In the ring mode, the current intensity in the path from the second ground terminal H to the first connection point G via the third radiator 30 and then to the ground via the capacitive tuning circuit 40 is uniform, and all currents are relatively strong, with no obvious distinction between strong and weak currents.

[0109] Please see Figure 10 The distance between the first connection point G and the third coupling terminal F is relatively small. The close proximity of the third coupling terminal F to the first connection point G makes it easier to excite the efficient ring mode. For the equivalent LC resonant circuit, the portion between the first connection point G and the second ground terminal H is equivalent to an inductor, and the portion between the first connection point G and the third coupling terminal F is equivalent to a capacitor. The longer the distance between the first connection point G and the third coupling terminal F, the greater the impact of the capacitance between them on the equivalent LC resonant circuit. This necessitates the use of traditional inductors to tune for low frequencies and makes it less likely to form the ring mode.

[0110] This application does not specifically limit the distance between the first connection point G and the third coupling end F. Optionally, in this embodiment, the distance between the first connection point G and the third coupling end F is less than or equal to 1 / 5 of the length of the third radiator 30. While satisfying the ring pattern, the position of the first grounding point and the position of the capacitive tuning circuit 40 can be set relatively flexibly, and it has the characteristics of low-frequency dual-wave independence and low-frequency dual-wave fusion.

[0111] Optionally, the first connection point G is located at the third coupling terminal F. The resonant current of the ring mode flows through the entire third radiator 30, and the entire length of the third radiator 30 is equivalent to an inductor. While satisfying the miniaturization of the third radiator 30, a ring current mode is formed to support the third low-frequency band. The ring current mode improves the efficiency of the second resonant mode, thereby improving the efficiency and bandwidth of the second low-frequency band.

[0112] The second resonant mode differs from the ring mode in that the second resonant mode is an intrinsic resonant mode where the electrical length of the second radiator 20 satisfies 1 / 4 wavelength of the first low-frequency band. The ring mode is a resonant mode where the electrical length of the third radiator 30 is much smaller than 1 / 4 wavelength of the third low-frequency band, in which case the third radiator 30 is equivalent to an inductor, and the third radiator 30 and the capacitive tuning circuit 40 form an equivalent LC resonant circuit. The ring mode is not an intrinsic resonant mode of the third radiator 30.

[0113] Optionally, the sub-band switching of the first low-frequency band is independent of the sub-band switching of the second low-frequency band, and the sub-band switching of the second low-frequency band is independent of the sub-band switching of the third low-frequency band. That is, the frequency bands supported by the first resonant mode, the second resonant mode, and the ring mode can all be switched independently, reducing constraints between supported frequency bands and thus supporting more complex frequency band combinations.

[0114] In one alternative implementation, please refer to Figure 10 The first radiator 10 further includes a first grounding terminal A and a second connection point B. The first grounding terminal A is disposed opposite to the first coupling terminal C. The second connection point B is located at the first grounding terminal A or between the first grounding terminal A and the first coupling terminal C. The coupling mode between the first radiator 10 and the second radiator 20 is a HE (magnetic field-electric field) mode.

[0115] In another implementation, please refer to Figure 11 The first coupling terminal C is a ground terminal. The first radiator 10 also includes a free end J and a second connection point B. The free end J is disposed opposite to the first coupling terminal C. The second connection point B is located between the first coupling terminal C and the free end J or located at the first coupling terminal C. The coupling mode between the first radiator 10 and the second radiator 20 is an HH (magnetic field-magnetic field) mode.

[0116] Please see Figure 12The antenna assembly 100 further includes a first switching tuning circuit T1. The first switching tuning circuit T1 includes a first switching unit K1 and a plurality of first impedance tuning branches R1. Each first impedance tuning branch R1 includes an inductor. The first switching unit K1 is electrically connected to the second connection point B and the plurality of first impedance tuning branches R1. The first switching unit K1 is used to switch the second connection point B to conduct with any one or more of the first impedance tuning branches R1, with the other end of each first impedance tuning branch R1 grounded, to switch a sub-band of the first low-frequency band. The first switching tuning circuit T1 is used to independently tune a sub-band of the first low-frequency band. For example, switching from the B28 band to the B5 band.

[0117] Each of the first impedance tuning branches R1 has a different impedance, and one end of each first impedance tuning branch R1 is electrically connected to the selection terminal of the first switching unit K1. The other end of each first impedance tuning branch R1 is electrically connected to the reference ground plane 500. The first switching unit K1 is a switching transistor, including but not limited to at least one of a triode, transistor, and field-effect transistor. The first impedance tuning branch R1 can be an inductor with different inductance values. When the first switching unit K1 switches to different first impedance tuning branches R1, the first impedance tuning branches R1 have different impedances, that is, different equivalent electrical lengths, thus adjusting the size of the sub-band of the first low-frequency band supported by the first resonant mode.

[0118] Please see Figure 13 The antenna assembly 100 further includes a second switching tuning circuit T2. The second switching tuning circuit T2 includes a second switching unit K2 and multiple second impedance tuning branches R2. Each second impedance tuning branch R2 includes an inductor. The second switching unit K2 is electrically connected to the feed terminal D and the multiple second impedance tuning branches R2. The other end of each second impedance tuning branch R2 is grounded. The second switching unit K2 is used to switch the feed terminal D connected to any one or more of the second impedance tuning branches R2 to switch a sub-band of the second low-frequency band. The second switching tuning circuit T2 is used to independently tune a sub-band of the second low-frequency band, for example, switching from the B5 band to the B8 band.

[0119] Please see Figure 14The capacitive tuning circuit 40 further includes a third switching unit K3 and multiple capacitor elements C0. The third switching unit K3 is electrically connected to the first connection point G and the multiple capacitor elements C0. The third switching unit K3 is used to switch the first connection point G to conduct with any one or more of the capacitor elements C0, thereby switching the sub-band of the third low-frequency band supported by the ring mode. The third switching tuning circuit is used to independently tune the sub-band of the third low-frequency band. When the first switching unit K1 switches the first connection point G to conduct with any one or more of the capacitor elements C0, the capacitor tuning circuit can be switched to have different capacitance values ​​(or impedance values). The capacitor elements C0 with different capacitance values ​​will tune the equivalent LC resonant circuit to different resonant points, thereby switching the ring mode to support different low-frequency sub-bands, such as switching from B8 to B5, from B5 to B28, etc.

[0120] It is understandable that the resonant current distribution of the first resonant mode is relatively independent of the resonant current distribution of the second resonant mode, and the resonant current distribution of the second resonant mode is relatively independent of the resonant current distribution of the third resonant mode.

[0121] When the first switching tuning circuit T1 switches the sub-band of the first low-frequency band, its impact on the sub-band of the second low-frequency band supported by the second resonant mode is small or negligible. Similarly, when the second switching tuning circuit T2 switches the sub-band of the second low-frequency band, its impact on the sub-band of the first low-frequency band supported by the first resonant mode is small or negligible. Furthermore, when the second switching tuning circuit T2 switches the sub-band of the second low-frequency band, its impact on the sub-band of the third low-frequency band supported by the third resonant mode is small or negligible. The third switching tuning circuit has little or no impact on the sub-bands of the second low-frequency band supported by the second resonant mode when switching the sub-bands of the third low-frequency band. Therefore, the sub-band switching of the first low-frequency band, the sub-band switching of the second low-frequency band, and the sub-band switching of the third low-frequency band are independent of each other to achieve three-wave three-cut. The frequency bands supported by the antenna assembly 100 can not only meet the B8 band + B28 band, but also realize the more complex L+L requirements of B28 / B5 / B8 dual waves.

[0122] This application does not specify the positions of the first radiator 10, the second radiator 20 and the third radiator 30 on the frame 320.

[0123] The first radiator 10 is disposed on the first side 323 near the bottom edge 322. The second radiator 20 is disposed on the bottom edge 322. A portion of the third radiator 30 is disposed on the bottom edge 322. Another portion of the third radiator 30 is disposed on the second side 324 near the bottom edge 322.

[0124] Please see Figure 15 and Figure 16 , Figure 15 The front view (the side where the display screen 200 is located) of the electronic device 1000, which is a candybar mobile phone. Figure 16 The above is a structural diagram of the electronic device 1000, which is a foldable mobile phone with the hinge on top.

[0125] In a left-hand grip scenario, the area of ​​the first side 323 near the bottom edge 322 is the first hand grip area Z1. The first hand grip area is the area that contacts the first side 323 when the left hand grips the electronic device 1000. The distance between the first hand grip area Z1 and the bottom edge 322 is less than or equal to 40mm.

[0126] In a right-hand grip scenario, the area of ​​the second side 324 near the bottom edge 322 is the second hand grip area Z2. The second hand grip area is the area that contacts the second side 324 when the electronic device 1000 is held by the right hand. The distance between the second hand grip area Z2 and the bottom edge 322 is less than or equal to 40mm.

[0127] The bottom edge 322 includes an open area, which is a region that cannot be touched by the right hand or the left hand when holding the device. Optionally, the open area Z3 of the bottom edge 322 is located in a region that is more than 10mm away from the first side edge 323 and the second side edge 324.

[0128] It is understandable that due to differences in hand size among different users, the position of their hand on the frame 320 of the electronic device 1000 will vary when different users hold the same electronic device 1000 with the same gesture. As an example, the hand-holding area described in this application can be a corresponding area formed when a user with any hand size holds the electronic device 1000 with the same gesture. For instance, the hand-holding area in this application can be the area where the frame 320 of the electronic device 1000 is covered by and in contact with the palm when a user with any hand size holds the electronic device 1000 in the same posture.

[0129] First, please refer to Figure 17 The second radiator 20 is located in the open area Z3 of the bottom edge 322. Thus, as the main radiator, the resonant current of the second radiator 20 will not be affected by hand grip, so as to ensure the antenna performance of the main operating frequency band (second low frequency band) in free space, left-hand grip or right-hand grip state, thereby improving the anti-hand grip performance of the electronic device 1000.

[0130] Then, please see Figure 17 The first radiator 10 has at least a portion of its high-current segment in the first resonant mode located in the first hand-held area Z1 to form a dielectric loading when held by the left hand, thereby improving the radiation efficiency of the first resonant mode when held by the left hand. The third radiator 30 has at least a portion of its high-current segment in the ring mode located in the second hand-held area Z2 to form a dielectric loading when held by the right hand, thereby improving the radiation efficiency of the third resonant mode when held by the right hand.

[0131] It is known that the second radiator 20 is located on the bottom edge 322 of the electronic device 1000. Whether the left hand is folded or the right hand is folded, the second radiator 20 cannot be held. Therefore, regardless of whether the electronic device 1000 is in an unfolded state or a folded state, holding it has little impact on the main mode performance of the antenna assembly 100. The absorption by the hand is small, so the reduction due to holding it is not large. The electronic device 1000 has anti-hand grip characteristics.

[0132] By designing the structure of the antenna assembly 100 and its mounting position on the frame 320, the high-current segment of the first radiator 10 is located within the first hand-held area Z1 of the first side 323, and the high-current segment of the third radiator 30 is located within the second hand-held area Z2 of the second side 324, so that the high-current segment can be held in a hand-held scenario, thereby forming a dielectric loading effect.

[0133] The following provides a detailed explanation of the dielectric loading formed by the antenna assembly 100 in the high-current section 110 when held in a hand grip: Since the high-current section is located in the first hand grip area Z1 of the first side 323, in a left-hand grip scenario, the palm contacts the high-current section. The effective dielectric constant of the palm is relatively large, for example, 25-40, much greater than the dielectric constant 0 in air. Therefore, the palm contacting the high-current section effectively changes the radiation environment of the electromagnetic waves radiated by the high-current section. The palm forms a high-dielectric-constant medium in the electromagnetic wave radiation space. Based on the principle that the wavelength of electromagnetic waves shortens in a high-dielectric-constant medium, having a medium (e.g., a palm) cover or surround the radiator can significantly reduce the antenna size in the corresponding frequency band; that is, dielectric loading can achieve miniaturization. In the electronic device 1000, since the length of the high current segment is equal before and after the hand is held, the equivalent dielectric constant around the high current segment is changed after the hand is held. Since the electrical length of the high current segment remains unchanged, according to the wavelength shortening effect, the radiation capability will shift towards the low frequency, that is, the peak radiation efficiency will shift towards the low frequency side.

[0134] In the first resonant mode, the high-current band encounters a high-dielectric-constant medium formed by the palm during radiation. Therefore, the peak radiation efficiency in the first resonant mode shifts towards the low-frequency side. Since the radiation efficiency of the first resonant mode gradually increases in the first low-frequency band and the high-frequency side of the first low-frequency band (i.e., the radiation efficiency in the high-frequency side of the first low-frequency band is higher than that in the first low-frequency band), the radiation efficiency in the first low-frequency band increases after the peak radiation efficiency shifts towards the low-frequency side. This means that the antenna assembly 100 described herein forms a dielectric loading in the hand-held state and the first resonant mode, thereby improving the radiation efficiency in the first resonant mode.

[0135] Generally, when a hand touches the radiator of the antenna assembly 100, the hand absorbs the electromagnetic waves radiated by the radiator. However, in this application, since the area touched by the palm is not the radiation segment where the first free end D is located, and the efficiency improvement brought by the palm's dielectric loading of the antenna assembly 100 is greater than the efficiency reduction brought by the palm's absorption, the overall effect is that the antenna assembly 100 forms dielectric loading in the hand-held state and the first resonant mode, thereby improving the radiation efficiency in the first resonant mode.

[0136] Please see Figure 18 The electronic device 1000 is a foldable electronic device. Both the first side 323 and the second side 324 can be bent into a folded or unfolded state. The top edge 321 and the bottom edge 322 are stacked on top of each other in the thickness direction of the electronic device 1000 in the folded state.

[0137] Please see Figure 18 The electronic device 1000 includes a first body 710 and a second body 720. The first body 710 and the second body 720 are movably connected (rotatably connected or slidably connected) to present a folded state or an unfolded state. The first body 710 includes a top edge 321. The second body 720 includes a bottom edge 322. When the electronic device 1000 is in the unfolded state, the top edge 321 and the bottom edge 322 are located on opposite sides of the electronic device 1000. When the electronic device 1000 is in the folded state, the top edge 321 and the bottom edge 322 overlap in the thickness direction. In other words, the top edge 321, the first portion of the first side edge 323, and the first portion of the second side edge 324 are located in the first body 710. The bottom edge 322, the second portion of the first side edge 323, and the second portion of the second side edge 324 are located in the second body 720.

[0138] For the foldable electronic device 1000, the efficiency is significantly affected by halving the area of ​​the reference ground plane 500 after folding, especially for low-frequency radiation dependent on the reference ground plane 500. Folding the electronic device 1000 has a substantial impact on the efficiency of the low-frequency antenna, with a maximum reduction of nearly 10 dB in the N28 band. Because the current distribution on the reference ground plane 500 is mostly concentrated vertically, the peak efficiency of the main ground plane shifts to higher frequencies, resulting in a significant decrease in radiation efficiency within the B28 band.

[0139] Please see Figure 8 In this embodiment, the ground current generated by the main antenna (the second radiator 20) on the reference ground 500 in the second resonant mode is mainly a lateral current. That is, the lateral current intensity of the ground current generated by the second radiator 20 on the reference ground 500 in the second resonant mode is greater than the longitudinal current intensity. Since the folding mainly results in a significant reduction in the longitudinal dimension of the reference ground 500, it has little impact on the current distribution of the second radiator 20 on the reference ground 500. In other words, the antenna assembly 100 provided in this application has good self-resonance characteristics and certain anti-folding characteristics, so as to further improve the radiation efficiency of the mid-to-high frequency antenna in the foldable electronic device 1000 after folding, and ensure the stability of the foldable electronic device 1000's call function when the cover is closed.

[0140] Please see Figure 19 , Figure 19 These are the S-reference curves and efficiency curves of the electronic device 1000 in folded free space provided in this application. Curve a is the S-parameter curve of the electronic device 1000 in folded free space. Curve b is the radiation efficiency curve of the electronic device 1000 in folded free space. Curve c is the overall efficiency curve of the electronic device 1000 in folded free space. It can be seen that in the folded scenario, the efficiency of the B28 band supported by the second resonant mode is approximately -10dB. The efficiency of this B28 band is quite good in practical applications when the electronic device 1000 is in a folded state.

[0141] The second radiator 20 is used as a monopole antenna. The grounding position of the monopole antenna is close to the corner of the reference ground plane 500, and the length of the second radiator 20 is shortened to achieve miniaturization of the LB antenna and improve the efficiency of the main mode of the low-frequency antenna itself. The coupling between the first radiator 10 and the second radiator 20 is in the form of HE, resulting in HE parasitism; the coupling between the third radiator 30 and the second radiator 20 is in the form of EE, resulting in ring mode parasitism.

[0142] The antenna assembly 100 described above forms three modes. The first resonant mode is dominated by a quarter-wavelength mode from the first ground terminal A to the first coupling slot N1, while a reverse current flows from the feed terminal D to the second coupling slot N2; this mode is the HE parasitic stub mode. The second resonant mode is the dominant mode, a quarter-wavelength mode on the second radiator 20. The third resonant mode is the ring mode of the third radiator 30, with the second ground terminal H connected to the capacitive tuning circuit 40, where the third radiator 30 is equivalent to an inductor and the capacitive tuning circuit 40 is a ground capacitor, forming an LC resonance; mode 3 is the ring mode.

[0143] Please see Figure 20 , Figure 20 These are the S-parameter curves and efficiency curves of the antenna assembly 100 provided in this application. Curve a refers to the S-parameter curve of the antenna assembly 100. Curve b refers to the radiation efficiency curve of the antenna assembly 100. Curve c refers to the overall efficiency curve of the antenna assembly 100.

[0144] The resonance at point 1 on the S-curve is the first resonant mode, the resonance at point 2 is the second resonant mode, and the resonance at point 3 is the third resonant mode. It can be seen that the first, second, and third resonant modes form a continuous frequency band covering 0.68-0.85 GHz.

[0145] As can be seen from the overall efficiency curve, an efficiency dip is formed after the resonance point of the first resonance mode and an efficiency bulge is formed at the resonance point of the second resonance mode; an efficiency dip is formed before the resonance point of the third resonance mode and an efficiency bulge is formed at the resonance point of the second resonance mode. That is, both the first and third resonance modes can improve the efficiency of the second resonance mode.

[0146] Please see Figure 21 , Figure 21 This application provides S-parameter curves for separately configuring the second radiator 20, configuring the first radiator 10 and the second radiator 20, configuring the second radiator 20 and the third radiator 30, and simultaneously configuring the first radiator 10, the second radiator 20 and the third radiator 30. Curve a is the S-parameter curve for separately configuring the second radiator 20. Curve b is the S-parameter curve for configuring the first radiator 10 and the second radiator 20. Curve c is the S-parameter curve for configuring the second radiator 20 and the third radiator 30. Curve d is the S-parameter curve for simultaneously configuring the first radiator 10, the second radiator 20 and the third radiator 30.

[0147] As can be seen, the resonant frequency of the first resonant mode is slightly lower than that of the second resonant mode (dominant mode), and the first resonant mode improves the in-band efficiency of the dominant mode. The resonant frequency of the ring mode is slightly higher than that of the second resonant mode (dominant mode), thus extending the bandwidth.

[0148] Please see Figure 22 , Figure 22 This application provides efficiency curves for setting up the second radiator 20 alone, setting up the first radiator 10 and the second radiator 20, setting up the second radiator 20 and the third radiator 30, and simultaneously setting up the first radiator 10, the second radiator 20 and the third radiator 30. Curve a1 is the efficiency curve for setting up the second radiator 20 alone. Curve b1 is the efficiency curve for setting up the first radiator 10 and the second radiator 20. Curve c1 is the efficiency curve for setting up the second radiator 20 and the third radiator 30. Curve d1 is the efficiency curve for simultaneously setting up the first radiator 10, the second radiator 20 and the third radiator 30.

[0149] Curve a2 is the efficiency curve when the second radiator 20 is set alone. Curve b2 is the efficiency curve when both the first radiator 10 and the second radiator 20 are set. Curve c2 is the efficiency curve when both the second radiator 20 and the third radiator 30 are set. Curve d2 is the efficiency curve when the first radiator 10, the second radiator 20, and the third radiator 30 are set simultaneously.

[0150] As can be seen, adding the first radiator 10 improves the in-band efficiency (0.7-0.8 GHz) of the second resonant mode (dominant mode) by approximately 0.5 dB. Adding the ring mode second radiator 20 increases the efficiency bandwidth of the second resonant mode (dominant mode) by approximately 50 MHz or more. Figure 22 It can be seen that the third low-frequency band and the second low-frequency band form a continuous frequency band. The efficiency bandwidth of the second low-frequency band when working alone is 0.7-0.82GHz (taking a return loss of -10dB as an example); the efficiency bandwidth of the third low-frequency band + the second low-frequency band is 0.7-0.87GHz (taking a return loss of -10dB as an example), which is an increase of 50MHz in efficiency bandwidth. The ring mode is also used to increase the efficiency bandwidth of the second low-frequency band.

[0151] The electronic device 1000 provided in this application embodiment includes a first radiator 10 comprising a first coupling terminal C, a second radiator 20 comprising a feed terminal D and a second coupling terminal E disposed opposite to each other, with a first coupling gap N1 formed between the feed terminal D and the first coupling terminal C, a third radiator 30 comprising a third coupling terminal F, a first connection point G, and a second ground terminal H, with a second coupling gap N2 formed between the third coupling terminal F and the second coupling terminal E, one end of a capacitive tuning circuit 40 electrically connected to the first connection point G, and the other end of the capacitive tuning circuit 40 grounded, a feed source 50 electrically connected to the feed terminal D, the feed source 50 being used to excite the first radiator 10 to form a first resonant mode supporting a first low-frequency band, and the feed source 50 also being used to excite the second radiator 20. The radiator 20 forms the second resonant mode supporting the second low-frequency band. The feed source 50 is also used to excite the third radiator 30 and the capacitive tuning circuit 40 to form the ring mode supporting the third low-frequency band. The resonant current of the ring mode goes to ground from the second ground terminal H through the first connection point G and the capacitive tuning circuit 40. The center frequency of the first low-frequency band is less than the center frequency of the second low-frequency band, and the center frequency of the second low-frequency band is less than the center frequency of the third low-frequency band. The first resonant mode is used to increase the bandwidth and efficiency of the second low-frequency band, and the ring mode is used to increase the bandwidth and efficiency of the second low-frequency band. The first resonant mode and the ring mode form a dual efficiency-enhancing effect of the second resonant mode, thereby improving the efficiency of the second low-frequency band of the main mode (the second resonant mode).

[0152] By placing the return-to-ground position of the second radiator 20 (the position of the grounding terminal of the grounding circuit 60) near the corner of the reference ground 500, the reference ground 500 can be excited to generate lateral and longitudinal currents, which participate in energy radiation, thereby improving the efficiency of the second low-frequency band. On the other hand, the lateral and longitudinal currents cancel each other out less in the far field, thus also improving the efficiency of the second low-frequency band. Although shortening the length of the second radiator 20 will lead to a decrease in the efficiency of the second resonant mode, since the aforementioned design of this embodiment has already improved the efficiency of the second resonant mode to a good level, even if the efficiency of the second radiator 20 is reduced due to the shortening of its length, it can still meet the usage standards. Therefore, this embodiment appropriately shortens the length of the second radiator 20 on the basis of the above, while ensuring the generation of the second resonant mode and having relatively good efficiency, reducing the space occupied by the antenna assembly 100, and realizing the miniaturization of the antenna assembly 100.

[0153] In this embodiment, the ground current excited by the second radiator 20 on the reference ground 500 in the second resonant mode is mainly a lateral current. That is, the lateral current intensity of the ground current excited by the second radiator 20 on the reference ground 500 in the second resonant mode is greater than the longitudinal current intensity. Since the folding mainly results in a significant reduction in the longitudinal dimension of the reference ground 500, it has little impact on the current distribution of the second radiator 20 on the reference ground 500. In other words, the antenna assembly 100 provided in this application has excellent self-resonance characteristics and certain anti-folding characteristics, so as to further improve the radiation efficiency of the mid-to-high frequency antenna in the foldable electronic device 1000 after folding, and ensure the stability of the foldable electronic device 1000's cover-and-talk function.

[0154] The second radiator 20 is located on the bottom edge 322 of the electronic device 1000. Whether the left hand is folded or the right hand is folded, the second radiator 20 cannot be held. Therefore, regardless of whether the electronic device 1000 is in an unfolded or folded state, holding it has little impact on the main mode performance of the antenna assembly 100. The absorption by the hand is small, so the reduction due to holding it is not large. The electronic device 1000 has anti-hand grip characteristics.

[0155] In summary, the tri-band LB structure provided in this application constructs the main mode using a laterally miniaturized monopole mode. It improves in-band efficiency by adding HE stubs and ring mode stubs to form dual parasitic stubs. This not only provides high efficiency and wide bandwidth coverage but also enables broadband multi-frequency and multi-switching functionality. The second radiator 20 is positioned in the open area Z3 of the bottom edge 322 to prevent the main antenna (second radiator 20) from being held by the hand in gripping scenarios. Positioning the second radiator 20 on the bottom edge 322 provides anti-folding characteristics, resulting in higher efficiency in closed-cover scenarios. The high-current segments of the first radiator 10 and the second radiator 20 are positioned in the hand gripping area in gripping scenarios, allowing the palm to apply dielectric loading to the high-current segments on the antenna, thereby improving low-frequency radiation efficiency. This design achieves dielectric loading by the palm in both left and right hand gripping scenarios, improving performance, balancing left and right hand gripping performance, and forming an anti-folding and anti-grip low-frequency antenna.

[0156] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application, and such improvements and refinements are also considered to be within the protection scope of this application.

Claims

1. An electronic device, characterized in that, Includes an antenna assembly, the antenna assembly comprising: The first radiator includes a first coupling end; The second radiator includes a feed end and a second coupling end arranged opposite to each other, and a first coupling gap is formed between the feed end and the first coupling end; The third radiator includes a third coupling end, a first connection point and a second grounding end, wherein a second coupling gap is formed between the third coupling end and the second coupling end; A capacitive tuning circuit, one end of which is electrically connected to the first connection point, and the other end of which is grounded; and A feed source electrically connected to the feed terminal is used to excite the first radiator and the second radiator to form a first resonant mode supporting a first low-frequency band. The feed source is also used to excite the second radiator to form a second resonant mode supporting a second low-frequency band. The feed source is also used to excite the third radiator and the capacitive tuning circuit to form a ring mode supporting a third low-frequency band. The resonant current of the ring mode is grounded from the second ground terminal through the first connection point and the capacitive tuning circuit. The center frequency of the first low-frequency band is less than the center frequency of the second low-frequency band, and the center frequency of the second low-frequency band is less than the center frequency of the third low-frequency band. The first resonant mode is used to form an efficiency bulge on the low-frequency side of the second low-frequency band. The ring mode is used to form an efficiency bulge on the high-frequency side of the second low-frequency band.

2. The electronic device as claimed in claim 1, characterized in that, The first resonant mode is the HE mode between the first radiator and the second radiator.

3. The electronic device as described in claim 2, characterized in that, The first radiator further includes a first grounding terminal disposed opposite to the first coupling terminal. The current in the first resonant mode includes a first sub-current flowing from the first grounding terminal to the first coupling terminal and a second sub-current flowing from the second coupling terminal to the feed terminal. The intensity of the first sub-current is greater than the intensity of the second sub-current. The current mode of the first sub-current is 1 / 4 wavelength mode of the center frequency point of the first low frequency band.

4. The electronic device as claimed in claim 3, characterized in that, The current in the second resonant mode flows from the second coupling terminal to the feed terminal, and the second resonant mode is the 1 / 4 wavelength mode of the center frequency point of the second low frequency band.

5. The electronic device as claimed in claim 1, characterized in that, The third low-frequency band forms a continuous frequency band with the second low-frequency band, and the ring mode is also used to increase the efficiency bandwidth of the second low-frequency band.

6. The electronic device as claimed in claim 1, characterized in that, The electronic device also includes a reference floor, which includes a first side and a second side that are bent and connected, and the connection between the first side and the second side forms a corner point. The antenna assembly further includes a grounding circuit, one end of which is electrically connected to the feed terminal, and the other end of which is grounded. The distance between the grounding terminal of the grounding circuit and the corner point is less than or equal to 1 / 16 wavelength of the center frequency of the second low-frequency band.

7. The electronic device as claimed in claim 6, characterized in that, The electrical length of the second radiator is less than 1 / 4 wavelength of the center frequency of the second low-frequency band; The grounding circuit also includes an inductor, one end of which is electrically connected to the feed terminal and the other end of which is electrically connected to the reference ground. The inductor is used to compensate for the electrical length of the second radiator.

8. The electronic device as claimed in claim 7, characterized in that, The electrical length of the second radiator is greater than or equal to 1 / 5 times the wavelength of 1 / 4 of the center frequency of the first low-frequency band.

9. The electronic device as claimed in claim 1, characterized in that, The electrical length of the third radiator is less than 1 / 4 wavelength of the third low-frequency band and greater than 1 / 16 wavelength of the third low-frequency band.

10. The electronic device as claimed in claim 1, characterized in that, The electronic device also includes a reference ground plane, and the ground current formed on the reference ground plane by the second radiator in the second resonant mode is mainly a transverse current.

11. The electronic device as claimed in claim 1, characterized in that, The capacitive tuning circuit includes at least one capacitor element, the capacitance of which is less than or equal to 10pF.

12. The electronic device as claimed in claim 1, characterized in that, The distance between the first connection point and the third coupling end is less than or equal to 1 / 5 of the length of the third radiator.

13. The electronic device as claimed in claim 1, characterized in that, The resonant current of the third radiator with respect to the ring mode is an equivalent inductance, and the capacitive tuning circuit and the resonant current of the third radiator with respect to the ring mode are equivalent LC circuits, with the resonant frequency of the equivalent LC circuit being the center frequency of the third low-frequency band.

14. The electronic device according to any one of claims 1-13, characterized in that, The sub-band switching of the first low-frequency band is independent of the sub-band switching of the second low-frequency band, the sub-band switching of the second low-frequency band is independent of the sub-band switching of the third low-frequency band, and the sub-band switching of the first low-frequency band is independent of the sub-band switching of the third low-frequency band.

15. The electronic device as claimed in claim 14, characterized in that, The first radiator further includes a first grounding terminal and a second connection point. The first grounding terminal is disposed opposite to the first coupling terminal, and the second connection point is located at the first grounding terminal or between the first grounding terminal and the first coupling terminal; or... The first coupling end is a grounding end. The first radiator also includes a free end and a second connection point. The free end is disposed opposite to the first coupling end. The second connection point is located between the first coupling end and the free end or located at the first coupling end. The antenna assembly further includes a first switching tuning circuit, which includes a first switching unit and a plurality of first impedance tuning branches. Each first impedance tuning branch includes an inductor. The first switching unit is electrically connected to the second connection point and the plurality of first impedance tuning branches. The first switching unit is used to switch the second connection point to conduct with any one or more of the first impedance tuning branches to switch the sub-band of the first low-frequency band.

16. The electronic device as claimed in claim 14, characterized in that, The antenna assembly further includes a second switching tuning circuit, which includes a second switching unit and a plurality of second impedance tuning branches. Each second impedance tuning branch includes an inductor. The second switching unit is electrically connected to the feed terminal and the plurality of second impedance tuning branches. The second switching unit is used to switch the feed terminal to be connected to any one or more of the second impedance tuning branches to switch the sub-band of the second low-frequency band.

17. The electronic device as claimed in claim 14, characterized in that, The capacitive tuning circuit further includes a third switching unit and multiple capacitor elements. The third switching unit is electrically connected to the first connection point and the multiple capacitor elements. The third switching unit is used to switch the first connection point to conduct with any one or more of the capacitor elements in order to switch the sub-band of the third low-frequency band.

18. The electronic device as described in any one of claims 1-13 and 15-17, characterized in that, The electronic device further includes a frame, which includes a top edge, a first side edge, a bottom edge, and a second side edge connected in sequence. The first radiator is located on the first side near the bottom edge, the second radiator is located on the bottom edge, a portion of the third radiator is located on the bottom edge, and another portion of the third radiator is located on the second side near the bottom edge; the electronic device is a foldable electronic device, and both the first side and the second side can be bent into a folded state or an unfolded state.

19. The electronic device as claimed in claim 18, characterized in that, The first side includes a first hand grip area, which is the area that contacts the first side when the left hand grips the electronic device; At least a portion of the high-current segment of the first radiator in the first resonant mode is located in the first hand-holding area to form a dielectric loading under the left hand-holding; The second side includes a second hand grip area, which is the area that contacts the second side when the right hand grips the electronic device; The high-current segment of the third radiator in the ring mode is located in the second hand grip area to form a dielectric loading under right-hand grip.

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