Cavity antenna and electronic equipment

Abstract

The utility model relates to the technical field of antennas, and provides a cavity antenna and electronic equipment, the cavity antenna comprises a circuit board, a metal cover, a feed structure and a metal member, and the circuit board is used for electrically connecting a transceiver of the electronic equipment; the metal cover is arranged on the circuit board to enclose a resonant cavity, and a radiation window is formed in one side of the resonant cavity; the feed structure is arranged at the radiation window and is electrically connected with the circuit board and the metal cover; the metal component is arranged in the resonant cavity. The electrical length of the antenna can be increased, and the radiation efficiency of the antenna is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of antennas, and particularly provides a cavity antenna and an electronic device. BACKGROUND

[0002] The cavity antenna is an antenna that uses a metal cavity structure to control electromagnetic wave propagation. The basic principle is to limit the propagation path of electromagnetic waves through the metal cavity to achieve directional radiation or signal reception.

[0003] In the existing cavity antenna design, ABS material medium is filled in the antenna to support the antenna cavity and adjust the working frequency. However, this material can cause energy loss of electromagnetic waves during propagation, i.e. dielectric loss, thereby reducing the overall radiation efficiency of the antenna. UTILITY MODEL CONTENT

[0004] The purpose of the embodiments of the present application is to provide a cavity antenna and an electronic device, aiming to solve the problem of low radiation efficiency of the existing cavity antenna due to the use of ABS material medium to adjust the frequency.

[0005] To achieve the above purpose, the technical solution adopted by the present application is:

[0006] The present application provides a cavity antenna, comprising:

[0007] A circuit board for electrically connecting a transceiver of an electronic device;

[0008] A metal cover arranged on the circuit board to enclose a resonant cavity, one side of the resonant cavity being provided with a radiation window;

[0009] A feeding structure arranged at the radiation window and electrically connected with the circuit board and the metal cover;

[0010] A metal member arranged in the resonant cavity.

[0011] The cavity antenna provided by the present application can increase the electrical length of the antenna by adding a metal member in the resonant cavity, and at the same time, it can play the role of tuning and supporting the metal cover. Compared with the existing ABS material medium, the present application can significantly reduce dielectric loss and improve the radiation efficiency of the antenna.

[0012] Optionally, the metal cover comprises:

[0013] A cover plate connected to the feeding structure on one side along the length direction;

[0014] A first side plate connected to the other side of the cover plate along the length direction and arranged opposite to the feeding structure;

[0015] A second side plate and a third side plate connected to opposite sides of the cover plate along the width direction.

[0016] The first side plate, the second side plate and the third side plate are connected to the circuit board to form the radiation window at opposite sides of the first side plate.

[0017] Optionally, the metal cover further comprises:

[0018] a support plate connected to one side of the cover plate along the length direction and arranged at the radiation window, the support plate being connected to the circuit board; the support plate is arranged between the second side plate and the feed structure with a spacing, and / or the support plate is arranged between the third side plate and the feed structure with a spacing.

[0019] Optionally, the bottom layer of the circuit board is a full copper layer, and in the circuit board within the enclosing area of the metal cover, all layers except the bottom layer are non-metal clearance areas formed after removing copper foils.

[0020] Optionally, the circuit board is integrated with a feed interface and an antenna matching network, the feed interface is arranged outside the resonant cavity and used to electrically connect the transceiver, the antenna matching network is arranged at the radiation window, and the feed interface is electrically connected to the feed structure through the antenna matching network.

[0021] Optionally, the antenna matching network comprises capacitors and inductors in series or in parallel.

[0022] Optionally, the metal cover and the feed structure are integrally formed;

[0023] and / or the feed structure is a metal sheet or a probe;

[0024] and / or the metal member is a metal strip or a metal sheet.

[0025] Optionally, the lowest resonant frequency of the cavity antenna is f0, and the wavelength λ0=c / f0, c is the speed of light;

[0026] The length of the resonant cavity is X, the width is Y, and the height is Z; the length of the metal member is L, and the height is H, which satisfy:

[0027] Y=0.25λ0;

[0028] YX<0.5λ0;

[0029] 0<Z<Y;

[0030] 0<L<Y;

[0031] H=Z.

[0032] Optionally, the cavity antenna has a first resonant frequency point and a second resonant frequency point, the first resonant frequency point is 2.45GHz, and the second resonant frequency point is 5.5GHz.

[0033] The application further provides an electronic device, comprising a transceiver and the cavity antenna described above, wherein the transceiver is used for electrically connecting the circuit board.

[0034] The electronic device provided by the application can increase the electrical length of the antenna and realize higher antenna radiation efficiency through the cavity antenna described above. BRIEF DESCRIPTION OF DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0036] Figure 1 The structural schematic diagram of the cavity antenna provided by the embodiments of the application is shown in the figure.

[0037] Figure 2 The structural exploded view of the cavity antenna provided by the embodiments of the application is shown in the figure.

[0038] Figure 3 The structural schematic diagram of the metal cover provided by the embodiments of the application is shown in the figure.

[0039] Figure 4 The S parameter curve diagram of the cavity antenna provided by the embodiments of the application is shown in the figure.

[0040] Figure 5 The S parameter curve comparison diagram of the cavity antenna provided by the embodiments of the application under different lengths of metal members is shown in the figure.

[0041] Figure 6 The radiation efficiency curve comparison diagram of the cavity antenna provided by the embodiments of the application under different filling media is shown in the figure.

[0042] Figure 7 The structural schematic diagram of the electronic device provided by the embodiments of the application is shown in the figure.

[0043] In the figure, various reference signs are as follows:

[0044] 1, circuit board; 2, metal cover; 3, feed structure; 4, metal member; 5, radiation window;

[0045] 6, cover plate; 7, first side plate; 8, second side plate; 9, third side plate; 10, support plate;

[0046] 11, non-metal clearance area; 12, feed interface; 13, antenna matching network; 14, capacitor;

[0047] 15, inductor; 16, housing; 17, connecting hole; 18, connecting column. DETAILED DESCRIPTION

[0048] The embodiments of the present application are described below in detail, examples of which are shown in the drawings, wherein the same or similar notations represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary, and are intended to explain the present application, and cannot be understood as a limitation of the present application.

[0049] In the description of the embodiments of the present application, it should be understood that the terms "length", "width", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the embodiments of the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the embodiments of the present application.

[0050] In addition, the terms "first", "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the embodiments of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited.

[0051] In the embodiments of the present application, unless otherwise specifically defined and limited, the terms "mounting", "connecting", "connecting", "fixing" and the like should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0052] In the existing cavity antenna design, the antenna cavity is supported and the operating frequency is adjusted by filling ABS material medium inside the antenna. However, such material can cause energy loss, i.e. dielectric loss, of electromagnetic waves during propagation, thereby reducing the overall radiation efficiency of the antenna.

[0053] To solve the above technical problems, the cavity antenna provided by the present application is provided by setting a metal member in the resonant cavity of the cavity antenna, instead of the traditional ABS material medium. This not only can increase the electrical length of the antenna, optimize its tuning characteristics, but also reduce the medium loss, thereby improving the radiation efficiency of the antenna.

[0054] In one embodiment, referring to Figures 1 to 3 The cavity antenna provided by the present application includes a circuit board 1, a metal cover 2, a feed structure 3, and a metal member 4. The circuit board 1 is used to electrically connect the transceiver (not shown in the figure) of the electronic device; the metal cover 2 is arranged on the circuit board 1 to enclose a resonant cavity, and a radiation window 5 is arranged on one side of the resonant cavity; the feed structure 3 is arranged at the radiation window 5 and electrically connected with the circuit board 1 and the metal cover 2; and the metal member 4 is arranged in the resonant cavity.

[0055] In this embodiment, the circuit board 1 serves as the basic component for electrical connection, which is responsible for connecting the transceiver of the electronic device with the antenna. The metal cover 2 is mounted on the circuit board 1 to enclose a resonant cavity, and a radiation window 5 is arranged on one side of the resonant cavity for electromagnetic wave transmission and reception. The feed structure 3 is located at the radiation window 5 and is electrically connected with the circuit board 1 and the metal cover 2, and also serves as a feed for electromagnetic waves, allowing electromagnetic waves to enter or exit the resonant cavity. The metal member 4 is arranged inside the resonant cavity, and its presence can increase the electrical length of the antenna, which is helpful for the tuning process and provides physical support for the metal cover 2.

[0056] The working modes of the cavity antenna provided by the present application include a transmission mode and a reception mode.

[0057] Transmission mode: when electromagnetic wave signals need to be transmitted, the electromagnetic waves generated by the transceiver are transmitted to the feed structure 3 through the circuit board 1. Then, these electromagnetic waves are fed into the resonant cavity and interact with the metal member 4 in the resonant cavity to produce a resonance effect. Finally, the adjusted electromagnetic waves are radiated outward through the radiation window 5.

[0058] Reception mode: conversely, in the reception process, external electromagnetic waves enter the resonant cavity through the radiation window 5, resonate in the resonant cavity, and then are transmitted to the transceiver through the feed structure 3 and the circuit board 1 for processing.

[0059] It can be understood that by adding the metal member 4 inside the resonant cavity, the electrical length of the antenna can be effectively increased without significantly increasing the physical size of the antenna. This is because the metal member 4 can change the propagation path of the electromagnetic waves in the resonant cavity, so that the electromagnetic waves need to bypass the metal member 4 and experience a longer effective path length in the resonant cavity. This effect is similar to extending the propagation distance of electromagnetic waves in a limited space.

[0060] And, since the metal member 4 has good electrical conductivity, it can reflect and guide electromagnetic waves, change the electromagnetic field distribution inside the resonant cavity, and thus adjust the resonant frequency of the resonant cavity to approach the target operating frequency, thereby optimizing the performance of the antenna. By adjusting the position, shape and number of the metal member 4, the resonant frequency of the resonant cavity can be further fine-tuned to better match the target operating frequency.

[0061] In addition, since metal has high electrical conductivity and low loss tangent, the metal member 4 will hardly cause additional energy loss compared to the existing ABS material medium, which allows more electromagnetic energy to be effectively transmitted, reflected and radiated rather than being absorbed or dissipated, thereby improving the overall radiation efficiency of the antenna.

[0062] Therefore, the cavity antenna provided by the embodiments of the present application can increase the electrical length of the antenna, optimize the tuning characteristics, reduce the medium loss, and thus improve the radiation efficiency of the antenna, and achieve more efficient electromagnetic wave transmission and reception performance. In addition, the additional support provided by the metal member 4 enhances the mechanical stability of the entire antenna and optimizes the overall structure and durability of the antenna.

[0063] In one embodiment, referring to Figures 1 to 3 As shown in the figure, the metal cover 2 includes a cover plate 6, a first side plate 7, a second side plate 8 and a third side plate 9. The cover plate 6 is connected to the feed structure 3 on one side along the length direction P. The first side plate 7 is connected to the cover plate 6 on the other side along the length direction P and is arranged opposite to the feed structure 3. The second side plate 8 and the third side plate 9 are connected to the opposite sides of the cover plate 6 along the width direction Q. The first side plate 7, the second side plate 8 and the third side plate 9 are connected to the circuit board 1 to form a radiation window 5 on the opposite side of the first side plate 7.

[0064] In this embodiment, the cover plate 6 is substantially rectangular in shape, and the cover plate 6 is the top part of the metal cover 2, and is connected to the feed structure 3 on one side along the length direction P. The first side plate 7, the second side plate 8 and the third side plate 9 are connected to the edges of the cover plate 6 to form a resonant cavity with an open side (the radiation window 5) on the circuit board 1.

[0065] The metal cover 2 can be an integrally formed structure. When designing, the edges of a metal plate can be bent towards the same side to form the cover plate 6, the first side plate 7, the second side plate 8 and the third side plate 9. Such a design can facilitate processing, simplify the structure, and improve the overall structural strength.

[0066] In one embodiment, referring to Figures 1 to 3As shown, the metal cover 2 further comprises: a support plate 10 connected to one side of the cover plate 6 along the length direction P and arranged at the radiation window 5, and the support plate 10 is connected to the circuit board 1; the support plate 10 is arranged between the second side plate 8 and the feed structure 3 at intervals, and / or the support plate 10 is arranged between the third side plate 9 and the feed structure 3 at intervals.

[0067] In this embodiment, since the radiation window 5 is an open structure, it is easy to cause the overall structure of the metal cover 2 to be not stable enough. The support plate 10 and the cover plate 6 can be an integral structure, which is convenient for processing and improves the overall structural strength. The support plate 10 is supported between the cover plate 6 and the circuit board 1, which can provide additional support for the metal cover 2 to prevent it from deforming due to vibration or other external forces during use, thereby ensuring the long-term stability of the antenna.

[0068] And the support plate 10 is designed at intervals, which can reduce the shielding of the radiation window 5 as much as possible to ensure that the electromagnetic waves can be smoothly transmitted and received through the radiation window 5, thereby maximizing the transmission efficiency of the electromagnetic waves.

[0069] Therefore, the embodiment of the present application introduces the support plate 10, which not only enhances the mechanical stability of the overall structure, but also reduces the shielding of the radiation window 5 through the interval design to ensure the efficient transmission of electromagnetic waves and further improve the reliability and performance of the antenna.

[0070] In one embodiment, referring to Figures 1 to 3 As shown, the metal cover 2 and the feed structure 3 are an integral structure.

[0071] In this embodiment, the feed structure 3 is integrally formed on one side of the cover plate 6 along the length direction P. By adopting an integral design, not only the mechanical strength and electromagnetic performance of the overall structure are enhanced, but also the manufacturing process is simplified and the production cost is reduced.

[0072] In one embodiment, the feed structure 3 can be a metal sheet or a probe.

[0073] In this embodiment, as Figures 1 to 3 As shown, the feed structure 3 can be a metal sheet, which is a conductive sheet that can be vertically bent and connected to the side edge of the cover plate 6 along the length direction P, fixed at the radiation window 5, and used for electrically connecting the circuit board 1.

[0074] The feed structure 3 can also be a probe, which is an elongated conductive rod, one end of the probe is connected to the side edge of the cover plate 6 along the length direction P, the other end extends into the resonant cavity, and the probe is used for electrically connecting the circuit board 1.

[0075] Transmitting mode: when the transceiver generates electromagnetic waves, the electromagnetic waves are transmitted through the circuit board 1 to the metal sheet or probe, and then the energy is coupled into the resonant cavity through the metal sheet or probe, and then radiated outward through the radiation window 5 after resonance.

[0076] Receiving mode: external electromagnetic waves enter the resonant cavity through the radiation window 5, and then the signal is transmitted to the circuit board 1 through the metal sheet or probe, and finally transmitted to the transceiver.

[0077] The embodiment of the application can select a suitable feed structure 3 according to specific antenna design requirements and application scenarios to improve the overall performance and reliability of the antenna.

[0078] In one embodiment, referring to FIGS. 1 and 2, Figure 2 and Figure 3 the metal member 4 is a metal strip or a metal sheet.

[0079] In this embodiment, the metal strip and the metal sheet can be made of copper, aluminum or the like, and can be arranged at a middle position of the resonant cavity and extend along the width direction Q of the cover plate 6. The metal strip or the metal sheet can be connected between the cover plate 6 and the circuit board 1 by laser welding, conductive adhesive bonding, screw fixing or the like to ensure good electrical connection.

[0080] In one embodiment, referring to FIGS. 1 and 2, Figures 1 to 3 the metal cover 2 can be made of copper, aluminum or the like, and the feed structure 3 is a metal sheet, which is an integral molding structure with the metal cover 2. The metal cover 2 is mainly surrounded by a rectangular cover plate 6 and three side plates with three side edges bent, and the remaining one side edge is not enclosed to form a radiation window 5. The side edge has a discontinuous integral molding support plate 10 and a metal sheet (feed structure 3).

[0081] The metal member 4 is a metal strip, which can be laser welded on the cover plate 6 of the metal cover 2 and parallel to the second side plate 8 and the third side plate 9. Except for the welding part connected with the cover plate 6, other parts are not connected with the cover plate 6. After the metal strip is welded, the bottom of the metal strip is flush with the bottoms of the three side plates to ensure the stability of the metal cover 2 on the circuit board 1. Then, the metal cover 2 and the metal strip are fixed and connected as a whole on the circuit board 1 to form a cavity antenna.

[0082] In one embodiment, referring to FIGS. 1 and 2, Figure 2 the bottom layer of the circuit board 1 is a full copper layer, and the circuit board 1 in the enclosed area of the metal cover 2 has a non-metal clearance area 11 formed by removing the copper foil except the bottom layer.

[0083] In this embodiment, the bottom layer of the circuit board 1 is a full copper layer, which provides a good ground plane and shielding effect, reduces the influence of external electromagnetic interference, and helps to improve the stability and reliability of the antenna.

[0084] Within the area enclosed by the metal cover 2, the copper foil of the remaining layers of the circuit board 1 (excluding the bottom layer, such as the top and middle layers) is removed, forming a non-metallic clearance area 11. This design reduces interference from the metal on these layers (top and middle layers) on the electromagnetic field within the resonant cavity, such as reflection and scattering, allowing more electromagnetic energy to be effectively used for transmission and reception, thereby improving the antenna's radiation efficiency. Furthermore, it increases the effective height inside the resonant cavity. This means there is more space for electromagnetic waves to propagate within the resonant cavity, thus optimizing the distribution of the electromagnetic field and improving the overall performance of the antenna.

[0085] Therefore, by designing the bottom layer of the circuit board 1 as a fully copper-covered layer and making the remaining layers clear, the interference with the electromagnetic field can be reduced, the effective height inside the cavity can be increased, and the propagation path of electromagnetic waves can be optimized, thereby improving the radiation efficiency of the antenna.

[0086] In one embodiment, refer to Figure 1 and Figure 2 As shown, the circuit board 1 integrates a power supply interface 12 and an antenna matching network 13. The power supply interface 12 is located outside the resonant cavity and is used to electrically connect the transceiver. The antenna matching network 13 is located at the radiation window 5. The power supply interface 12 is electrically connected to the power supply structure 3 through the antenna matching network 13.

[0087] In this embodiment, the power supply interface 12 is located outside the resonant cavity, near the edge of the circuit board 1. It is used to transmit the electromagnetic wave signal generated by the transceiver to the cavity antenna and to transmit the electromagnetic wave signal received by the cavity antenna back to the transceiver. Different types of power supply interfaces 12 (such as SMA connectors, coaxial cables, etc.) can be selected according to actual needs, facilitating integration and maintenance.

[0088] Antenna matching network 13 is located at the radiation window 5, adjacent to the feed structure 3, to reduce signal transmission path losses. Antenna matching network 13 can effectively adjust the antenna's input impedance to match the transceiver's output impedance, reducing reflection losses and improving energy transmission efficiency. Furthermore, by adjusting the component parameters (such as inductance and capacitance values) in antenna matching network 13, the antenna's resonant frequency can be fine-tuned to achieve the target operating frequency, thus improving antenna performance.

[0089] Transmission mode: The electromagnetic wave signal generated by the transceiver is transmitted to the antenna matching network 13 through the feed interface 12. After impedance matching by the antenna matching network 13, it is transmitted to the feed structure 3. Then, after resonance in the resonant cavity through the feed structure 3, it is radiated outward through the radiation window 5.

[0090] Transmitting mode: In this mode, the signal is transmitted from the transceiver to the antenna through the feed interface 12, the antenna matching network 13, the feed structure 3, and the radiation window 5.

[0091] It can be understood that good impedance matching can reduce the reflection loss of the signal in the transmission process, so that more electromagnetic energy can be effectively utilized, thereby improving the radiation efficiency of the antenna. And impedance matching is not only suitable for transmitting mode, but also suitable for receiving mode, ensuring that as little energy as possible is lost in the transmission process, improving the overall transmission efficiency.

[0092] In one embodiment, referring to FIG. 1, the antenna matching network 13 includes a series or parallel capacitor 14 and inductor 15. Figure 2

[0093] In this embodiment, different fixed value capacitors or different fixed value inductors can be selected according to actual debugging, of course, appropriate adjustable capacitors and adjustable inductors can also be selected according to specific needs, for example, the capacitor 14 includes air dielectric adjustable capacitor, ceramic dielectric adjustable capacitor, etc.; the inductor 15 includes magnetic core adjustable inductor, air core coil adjustable inductor, etc.

[0094] By adjusting the values of the capacitor 14 and the inductor 15, the resonant frequency of the antenna can be accurately adjusted to better adapt to the target working frequency. And the capacitor 14 and the inductor 15 can be dynamically adjusted according to actual needs, so that the input impedance of the antenna is always matched with the output impedance of the transceiver, reducing the reflection loss and improving the energy transmission efficiency.

[0095] Therefore, the embodiments of the present application can improve the tuning accuracy and frequency response range of the antenna by introducing a series capacitor 14 and inductor 15 in the antenna matching network 13, and also improve flexibility and adaptability, so as to be suitable for various application scenarios.

[0096] In one embodiment, the lowest resonant frequency of the cavity antenna is f0, the wavelength λ0=c / f0, c is the speed of light; the length of the resonant cavity is X, the width is Y, and the height is Z; the length of the metal member 4 is L, and the height is H, then:

[0097] Y=0.25λ0;

[0098] Y<X<0.5λ0;

[0099] 0<Z<Y;

[0100] 0<L<Y;

[0101] H=Z.

[0102] ​In this embodiment, according to the lowest resonant frequency f0 and the corresponding wavelength λ0 of the cavity antenna, the dimensions X, Y and Z of the resonant cavity can be calculated to ensure that each dimension meets the design requirements to achieve the best resonant effect. And according to the size of the resonant cavity, the length L and height H of the metal member 4 are reasonably designed to ensure that it can not only increase the electrical length but also provide sufficient support.

[0103] The embodiments of the present application can optimize the resonant frequency and electromagnetic field distribution of the antenna, reduce unnecessary energy loss, and improve the radiation efficiency by reasonably designing the size of the resonant cavity and the parameters of the metal member. In particular, by setting a specific proportional relationship (such as Y = 0.25 λ0 and Y < X < 0.5 λ0), it can ensure that the antenna forms a suitable standing wave mode in different dimensions, thereby achieving efficient resonance. In addition, the design of the metal member 4 not only increases the electrical length, but also provides additional physical support, enhancing the mechanical stability and electromagnetic performance of the structure.

[0104] In one embodiment, the cavity antenna has a first resonant frequency point and a second resonant frequency point, the first resonant frequency point is 2.45 GHz, and the second resonant frequency point is 5.5 GHz.

[0105] In this embodiment, the cavity antenna is designed as a dual-band WiFi antenna with two resonant frequency points: the first resonant frequency point is 2.45 GHz, covering the range of 2.402 GHz to 2.482 GHz; the second resonant frequency point is 5.5 GHz, covering the range of 5.15 GHz to 5.85 GHz. This design can support common dual-band WiFi communication standards and is suitable for a variety of wireless communication devices, thereby meeting diverse needs.

[0106] For example: the length of the resonant cavity is 53.44 mm, the width is 30.19 mm, and the height is 1.7 mm. The metal member 4 can be a square metal strip with a length of 15 mm, a width of 0.3 mm, and a height of 1.7 mm. The thickness of the circuit board 1 is 0.6 mm. As shown in Figure 4 The S-parameter curve of the cavity antenna of this embodiment is obtained by electromagnetic simulation software, reflecting the reflection coefficient bandwidth of the cavity antenna, with frequency as the horizontal coordinate and S-parameter as the vertical coordinate, and at least two resonant frequency points.

[0107] In addition, the influence of metal strips of different lengths (including no metal strip, 5 mm metal strip, 10 mm metal strip, and 15 mm metal strip) on the antenna resonance is as shown in Figure 5 The reflection coefficient bandwidth of the cavity antenna under different lengths of metal strips is reflected, with frequency as the horizontal coordinate and S-parameter as the vertical coordinate. It can be seen that as the length of the metal strip increases, the antenna resonant frequency gradually shifts to low frequency.

[0108] The radiation efficiency of the cavity antenna provided in the application is described below in combination with a specific simulation example. In the example, the length, width and height of the resonant cavity are 53.44mm*30.19mm*1.7mm respectively.

[0109] The comparative example: an ABS material medium with a length, width and height of 15mm*10mm*1.7mm respectively, a dielectric constant of 3.6 and a loss tangent of 0.025 is filled in the middle of the resonant cavity.

[0110] The embodiment of the application: a metal strip with a length, width and height of 15mm*0.3mm*1.7mm respectively is filled in the middle of the resonant cavity.

[0111] As shown in Figure 6 , the abscissa is frequency and the ordinate is radiation efficiency. It can be seen that the resonant frequencies generated by the comparative example and the embodiment of the application can cover the target resonant frequency band 2.402GHz to 2.482GHz and 5.15GHz to 5.85GHz, but the radiation efficiency of the two is obviously different. The radiation efficiency of the embodiment of the application is obviously higher than that of the comparative example. Therefore, compared with the existing ABS material medium, the application can effectively improve the radiation efficiency of the antenna by introducing a metal strip into the resonant cavity of the cavity antenna.

[0112] In one embodiment, referring to Figure 2 and Figure 7 , the application further provides an electronic device, which comprises a transceiver (not shown in the figure) and the cavity antenna of the above embodiment, and the transceiver is used to electrically connect the circuit board 1.

[0113] Specifically, the electronic device further comprises a shell 16, the transceiver and the cavity antenna are arranged in the shell 16, and the circuit board 1 of the cavity antenna is provided with a connecting hole 17 at each of the four top corners, the shell 16 is provided with a connecting column 18 connected to the connecting hole 17 one by one to realize fixation, and the feeding interface 12 on the circuit board 1 is electrically connected to the transceiver through a wire to realize signal transmission. The specific type of the electronic device of the application is not particularly limited, which can be, for example, a tablet computer, a notebook computer or the like.

[0114] Since the electronic device provided in the embodiment of the application comprises the cavity antenna of the above embodiment, it has all the technical effects of the cavity antenna of the above embodiment, which will not be described here.

[0115] The above is only a preferred embodiment of the application and does not limit the embodiments of the application. Any modification, equivalent replacement and improvement made within the spirit and principle of the embodiments of the application shall be included in the protection scope of the embodiments of the application.

Claims

1. A cavity antenna, characterized by, The application relates to a cavity antenna. The cavity antenna comprises: a circuit board for electrically connecting a transceiver of an electronic device; a metal cover arranged on the circuit board to enclose a resonant cavity, the resonant cavity being provided with a radiation window on one side; a feeding structure arranged at the radiation window and electrically connected with the circuit board and the metal cover; 2. The cavity antenna of claim 1, wherein, a metal member arranged in the resonant cavity. The metal cover comprises: a cover plate connected with the feeding structure on one side along a length direction; a first side plate connected with the cover plate on the other side along the length direction and arranged opposite to the feeding structure; a second side plate and a third side plate connected with the cover plate on opposite sides along a width direction; 3. The cavity antenna of claim 2, wherein, wherein the first side plate, the second side plate and the third side plate are connected with the circuit board to form the radiation window on opposite sides of the first side plate. The metal cover further comprises:

4. The cavity antenna of claim 1, wherein, a support plate connected with the cover plate on one side along the length direction and arranged at the radiation window, the support plate being connected with the circuit board; the support plate is arranged between the second side plate and the feeding structure at intervals and / or the support plate is arranged between the third side plate and the feeding structure at intervals.

5. The cavity antenna of claim 1, wherein, A bottom layer of the circuit board is a full copper layer, and in the circuit board within the enclosed area of the metal cover, all layers except the bottom layer are non-metal clearance areas formed after the copper foil is removed.

6. The cavity antenna of claim 5, wherein, The circuit board is integrated with a feeding interface and an antenna matching network, the feeding interface is arranged outside the resonant cavity and used for electrically connecting the transceiver, and the antenna matching network is arranged at the radiation window, the feeding interface is electrically connected with the feeding structure through the antenna matching network.

7. The cavity antenna of claim 1, wherein, The antenna matching network comprises capacitors and inductors in series or in parallel. The metal cover and the feeding structure are an integral structure; and / or the feeding structure is a metal sheet or a probe; 8. The cavity antenna according to any one of claims 1 to 7, wherein, and / or the metal member is a metal strip or a metal sheet. The lowest resonant frequency of the cavity antenna is f0, and the wavelength is lambda0=c / f0, c is the speed of light; the length of the resonant cavity is X, the width is Y, and the height is Z; the length of the metal member is L, and the height is H, which satisfy: Y=0.25 lambda0; YX<0.5 lambda0; 0<Z<Y; 0<L<Y; 9. The cavity antenna of claim 8, wherein, H=Z.

10. An electronic device, comprising: The cavity antenna has a first resonant frequency point and a second resonant frequency point, the first resonant frequency point is 2.45 GHz, and the second resonant frequency point is 5.5 GHz. The application further relates to an electronic device comprising: a transceiver and the cavity antenna according to any one of claims 1 to 9, the transceiver being used for electrically connecting the circuit board.

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