Miniaturized cavity antenna and electronic equipment

Abstract

The invention provides a miniaturized cavity antenna and electronic equipment, and relates to the technical field of antennas. The miniaturized cavity antenna comprises a circuit board, a feed component, a ground feed component, a first tuning circuit, a second tuning circuit and a metal cover, a resonant cavity is defined by the metal cover and the circuit board, a long side and a short side connected with the metal cover are provided with a first radiation slot and a second radiation slot respectively, and the ground feed component is arranged at the joint of the long side and the short side. The feed component is arranged on the short side, the size of the long side is 1 / n wavelength of a first frequency, n is greater than or equal to 3, the position of the feed component on the short side meets the 1 / n wavelength of a second frequency, and the first tuning circuit and the second tuning circuit are used for tuning fed radio frequency signals respectively, the first radiation slot radiates a first electromagnetic wave of a first frequency outwards and the second radiation slot radiates a second electromagnetic wave of a second frequency outwards. Therefore, the volume of the cavity antenna can be reduced, the cost of the cavity antenna can be reduced, and the performance of the cavity antenna can be ensured.

Description

Technical Field

[0001] This application relates to the technical field of antennas, and in particular, to a miniaturized cavity antenna and an electronic device. Background Art

[0002] An antenna is a transducer that can convert a guided wave (an electromagnetic wave in which the electromagnetic energy is confined within a finite cross-section and propagates in a definite direction) into an electromagnetic wave propagating in free space, or vice versa. Currently, in electronic devices such as mobile phones, drones, tablet computers, satellite phones, and laptop computers, cavity antennas are usually used to achieve wireless communication because cavity antennas have many excellent characteristics such as high gain, low loss, compact structure, good stability, and strong anti-interference ability.

[0003] In the related art, a cavity antenna includes a cavity, a radiation unit, and a feeding network. The radiation unit can radiate electromagnetic waves to the outside or receive electromagnetic waves from the outside. The feeding network can transmit the radio frequency signal from the transmitter to the radiation unit or transmit the received radio frequency signal from the radiation unit to the receiver. The cavity can provide a relatively stable electromagnetic environment for the radiation unit and impose certain constraints and adjustments on the electromagnetic field of the radiation unit, thereby improving the performance of the antenna. In theory, the larger the cavity space of the cavity antenna, the better the performance of the cavity antenna. However, the increase in internal components of electronic devices, the trend of thinning the all-metal appearance, and the selling points such as large batteries and large speakers will all compress the design space of the cavity antenna, which results in an increasingly smaller clearance of the cavity antenna. If the size of the cavity antenna is reduced, then the performance of the cavity antenna will inevitably be reduced, making it impossible to balance the volume, cost, and performance of the cavity antenna. Summary of the Invention

[0004] This application provides a miniaturized cavity antenna and an electronic device, aiming to solve the problems in the related art that the cavity antenna has a large volume, high cost, and cannot balance with performance.

[0005] To solve the above-mentioned drawbacks existing in the related art, a first aspect of the present application provides a miniaturized cavity antenna, which is used to radiate a first electromagnetic wave of a first frequency and / or a second electromagnetic wave of a second frequency. It includes a circuit board, a metal cover, a feeding component, a grounding component, and a first tuning circuit and a second tuning circuit arranged on the circuit board. The metal cover covers the circuit board and encloses a resonant cavity with the circuit board. The metal cover has a first radiation slot and a second radiation slot, which are respectively located on the target long side and the target short side where the metal cover is connected. The length of the target long side is 1 / n of the wavelength of the first frequency and n≥3. The connection between the target long side and the target short side is a strong electric field region. One end of the grounding component is arranged on the metal cover and located at the center of the strong electric field region, and the other end is arranged on the circuit board and grounded through the first tuning circuit. One end of the feeding component is arranged on the target short side, and the other end is arranged on the circuit board and is used to be electrically connected to an external radio frequency circuit through the second tuning circuit. The target distance between the feeding component and the end point of the target short side away from the grounding component is 1 / n of the wavelength of the second frequency, and the length of the target short side is less than or equal to twice the target distance. Specifically, the radio frequency circuit is used to feed a radio frequency signal of the first frequency and / or the second frequency into the resonant cavity to excite an electromagnetic field in the resonant cavity; the first tuning circuit is used to tune the radio frequency signal to the first frequency, so that a strong resonance of the first frequency is formed at the first radiation slot, and the first electromagnetic wave is radiated through the first radiation slot; the second tuning circuit is used to tune the radio frequency signal to the second frequency, so that a strong resonance of the second frequency is formed at the second radiation slot, and the second electromagnetic wave is radiated through the second radiation slot.

[0006] In some implementation solutions, the metal cover includes a metal top plate, a long metal side plate, and a short metal side plate. The metal top plate includes two opposite long sides and two opposite short sides. One side of the long metal side plate and the short metal side plate are respectively arranged on one of the connected long sides and one of the short sides, and the other sides of the long metal side plate and the short metal side plate are both arranged on the circuit board. The other long side and the other short side are respectively the target long side and the target short side. The first radiation slot is between the grounding component and the short metal side plate, and the second radiation slot is between the grounding component and the long metal side plate. In one or more of the implementation solutions, the long metal side plate and the short metal side plate have the same structure, and both include a connecting plate bent and extended from the metal top plate to the circuit board and a supporting plate bent and extended from the connecting plate to the circuit board; the feeding component and the grounding component have the same structure, and both include an extended portion bent and extended from the metal top plate to the circuit board and a connecting portion bent and extended from the extended portion to the circuit board.

[0007] In some implementation solutions, in addition to including the structure given above, the miniaturized cavity antenna further includes a coaxial cable and a coaxial cable socket arranged on the circuit board and electrically connected to the feeding component. One end of the coaxial cable is electrically connected to the coaxial cable socket, and the other end is used to be electrically connected to the radio frequency circuit.

[0008] In some implementation solutions, the first frequency is 2.4 GHz and the second frequency is 5 GHz; on this basis, the length of the target long side is 25 to 35 mm, and the length of the target short side is 20 to 30 mm. Preferably, the length of the target long side is 28 ± 2 mm, and the length of the target short side is 26 ± 2 mm.

[0009] In some implementation solutions, the resonant cavity is filled with an air medium.

[0010] The second aspect of the present application provides an electronic device, which includes an electronic device body and the miniaturized cavity antenna provided in the first aspect of the present application. A main board is provided in the electronic device body, a radio frequency circuit is provided on the main board, the miniaturized cavity antenna is provided in the electronic device body, the feeding component in the miniaturized cavity antenna is electrically connected to the radio frequency circuit, and the length, width, and thickness directions of the miniaturized cavity antenna are respectively consistent with the length, width, and thickness directions of the electronic device body.

[0011] For the miniaturized cavity antenna provided in the first aspect of the present application, it adopts size optimization based on fractional multiples of the wavelength (for example, the length of the target long side is set to 1 / n of the wavelength of the first frequency, the target distance between the feeding component and the end point of the target short side away from the ground feeding component is equal to 1 / n of the wavelength of the second frequency, and the length of the target short side is less than or equal to twice the target distance, etc.), thereby accurately controlling the size of the resonant cavity. Taking n=4 as an example, the length of the target long side is approximately as low as 28 mm, and the length of the target short side is approximately as low as 26 mm. Compared with the cavity antenna of the traditional solution (cavity length is approximately 45~65 mm, width is approximately 25~40 mm), the overall volume can be reduced by 30~50%, and in electronic devices with strict space requirements (such as mobile phones, tablets, etc.), it can greatly save internal space and provide more flexibility for the layout of other components. In addition, the present application sets a first tuning circuit and a second tuning circuit to tune the radio frequency signals of the first frequency and the second frequency respectively, ensuring that the signals of each frequency band in the miniaturized resonant cavity can effectively excite strong resonance (that is, the first tuning circuit makes the first radiation gap accurately form a strong resonance of the first frequency, and the second tuning circuit makes the second radiation gap stably generate a strong resonance of the second frequency), avoiding mutual interference of dual-band signals, so that the radiation efficiency of the antenna can still be maintained at a high level when working in multiple frequency bands. Compared with the cavity antenna with single-frequency radiation in dual-frequency application scenarios in traditional solutions, the performance is significantly improved; the first radiation gap and the second radiation gap in the present application are respectively located on the target long side and the target short side of the metal cover, and the strong electric field area at the junction of the two is used for feeding and ground feeding, and the electromagnetic energy is cleverly concentrated and guided to the gap for radiation. This design can make the radiation pattern of the antenna more directional, and form a strong signal coverage perpendicular to the target long side and the target short side, and the gain can be improved. It can be seen that the present application can reduce the size of the antenna and reduce its cost while ensuring the performance of the antenna, truly balancing the size, cost and performance of the antenna, and providing a reliable and efficient solution for wireless communication of electronic devices.

[0012] The electronic device provided in the second aspect of the present application includes the miniaturized cavity antenna provided in the first aspect of the present application, and thus has all the advantages of the miniaturized cavity antenna. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions in the related technologies or the embodiments of the present application, the drawings required for use in the description of the related technologies or the embodiments of the present application will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, not all embodiments. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0014] Figure 1 Schematic diagram of the structure of a miniaturized cavity antenna from a perspective provided by an embodiment of the present application;

[0015] Figure 2 Side view of the miniaturized cavity antenna provided by an embodiment of the present application;

[0016] Figure 3 Schematic diagram of the structure of a miniaturized cavity antenna from another perspective provided by an embodiment of the present application;

[0017] Figure 4 Provided by an embodiment of the present application Figure 2 Local enlarged view at position B in

[0018] Figure 5 Provided by an embodiment of the present application Figure 1 Local enlarged view at position A in

[0019] Figure 6 Schematic diagram of the structure of an electronic device provided by an embodiment of the present application;

[0020] Figure 7 Exploded view of the electronic device provided by an embodiment of the present application.

[0021] The marks shown in the above respective drawings represent respectively: 1 - circuit board, 2 - metal cover, 3 - feeding component, 4 - grounding component, 5 - first tuning circuit, 6 - second tuning circuit, 7 - coaxial socket, 8 - coaxial cable, 9 - resonant cavity, 10 - electronic device body, 21 - first radiation slot, 22 - second radiation slot, 23 - metal top plate, 24 - long metal side plate, 25 - short metal side plate, 251 - connecting plate, 252 - support plate, 41 - extension part, 42 - connecting part, 101 - main board, 102 - housing, 103 - screen. Detailed implementation manners

[0022] In related technologies, the larger the cavity space of a cavity antenna, the better its performance. However, the increase of internal devices in an electronic device, the trend of thinning the all-metal appearance, and the selling points such as large batteries and large speakers will all compress the design space of the cavity antenna, which results in the increasingly smaller clearance of the cavity antenna. If the size of the cavity antenna is reduced, its performance will inevitably be reduced, that is, it is impossible to balance the volume, cost and performance of the cavity antenna. In view of this, the present application proposes a miniaturized cavity antenna and an electronic device in the following embodiments to solve the above drawbacks existing in related technologies.

[0023] In order to make the objectives, technical solutions and advantages of the present application more obvious and understandable, the present application will be clearly and completely described below in conjunction with the embodiments of the present application and the corresponding drawings, wherein the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions from beginning to end. It should be understood that the various embodiments of the present application described below are only used to explain the present application and are not used to limit the present application. That is, based on the various embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application. In addition, the technical features involved in the various embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0024] Please refer to Figure 1 and Figure 2 , Figure 1 which is a schematic structural view of a miniaturized cavity antenna from a perspective, Figure 2 and which is a side view of the miniaturized cavity antenna. This embodiment provides a miniaturized cavity antenna for radiating a first electromagnetic wave of a first frequency and / or a second electromagnetic wave of a second frequency. That is, the miniaturized cavity antenna has two different radiation modes, namely a single-frequency radiation mode and a dual-frequency radiation mode. In the dual-frequency radiation mode, the miniaturized cavity antenna can simultaneously radiate the first electromagnetic wave and the second electromagnetic wave, while in the single-frequency mode, the miniaturized cavity antenna will only radiate one electromagnetic wave (the first electromagnetic wave or the second electromagnetic wave). It should be noted that since 2.4 GHz and 5 GHz are the two most commonly used frequency bands in wireless communication (such as WIFI, etc.), the first frequency in this embodiment is 2.4 GHz and the second frequency is 5 GHz. It should also be noted that the operating mode of the miniaturized cavity antenna in this embodiment is the transverse electric (TE) mode. For example, the miniaturized cavity antenna operates based on the TE0.25,0,0.25 mode.

[0025] Specifically, the miniaturized cavity antenna includes a circuit board 1, a metal cover 2, a feeding component 3, a grounding component 4, a first tuning circuit 5 and a second tuning circuit 6 disposed on the circuit board 1. The metal cover 2 is disposed on the circuit board 1 and encloses a resonant cavity 9 with the circuit board 1. The inside of the resonant cavity 9 is filled with an air medium. The metal cover 2 has a first radiation slot 21 and a second radiation slot 22. The first radiation slot 21 and the second radiation slot 22 are respectively located on the target long side and the target short side where the metal cover 2 is joined. The length of the target long side is 1 / n of the wavelength of the first frequency and n≥3. The joint of the target long side and the target short side is a strong electric field region. One end of the grounding component 4 is disposed on the metal cover 2 and located at the center of the strong electric field region. The other end of the grounding component 4 is disposed on the circuit board 1 and grounded through the first tuning circuit 5. One end of the feeding component 3 is disposed on the target short side. The other end of the feeding component 3 is disposed on the circuit board 1 and electrically connected to an external radio frequency circuit through the second tuning circuit 6. The feeding component 3 is also located in the strong electric field region like the grounding component 4. The target distance between the feeding component 3 and the end point of the target short side away from the grounding component 4 is 1 / n of the wavelength of the second frequency. The length of the target short side is less than or equal to twice the target distance. It should be noted that the circuit board 1 and the metal cover 2 in this embodiment are integrally packaged, so as to eliminate adverse factors such as assembly errors, thereby reducing the manufacturing cost of the miniaturized cavity antenna.

[0026] In this embodiment, the length of the target long side is 25 - 35 mm, and the length of the target short side is 20 - 30 mm; further, the length of the target long side can be 28±2 mm, and the length of the target short side can be 26±2 mm; among them, the length of the target long side is preferably 28 mm, and the length of the target short side is preferably 26 mm. In addition, it should be noted that n in this embodiment is preferably 4. Then the length of the target long side of the metal cover 2 is 1 / 4 of the wavelength of 2.4 GHz, and "1 / 4 of the wavelength of 2.4 GHz" in this embodiment means "1 / 4 of the corresponding wavelength in the fundamental mode operating state of the antenna in the 2.4 GHz frequency band", and this size is approximately equal to 28 mm. Through this size design, the signal radiation and reception performance of the antenna in the 2.4 GHz frequency band are optimized; similarly, "1 / 4 of the wavelength of 5 GHz" in this embodiment means "1 / 4 of the corresponding wavelength in the fundamental mode operating state of the antenna in the 5 GHz frequency band", and this size is approximately equal to 26 mm. Through this size design, the signal radiation and reception performance of the antenna in the 5 GHz frequency band are optimized. It should also be noted that the thickness of the metal cover 2 is greater than or equal to 2.7 mm and less than or equal to 2.9 mm.

[0027] In this embodiment, the radio frequency circuit is used to feed radio frequency signals of the first frequency and / or the second frequency into the resonant cavity 9, so as to excite an electromagnetic field in the resonant cavity 9; the first tuning circuit 5 is used to tune the radio frequency signal to the first frequency, so as to form a strong resonance at the first radiation slot 21 in the resonant cavity 9, thereby radiating the first electromagnetic wave outward through the first radiation slot 21; the second tuning circuit 6 is used to tune the radio frequency signal to the second frequency, so as to form a strong resonance at the second radiation slot 22 in the resonant cavity 9, thereby radiating the second electromagnetic wave outward through the second radiation slot 22. In addition, it should be noted that the tuning circuit (i.e., the first tuning circuit 5 and the second tuning circuit 6) is usually composed of devices such as capacitors, inductors, amplifiers, filters, frequency synthesizers, etc., and its work mainly includes impedance matching (adapting the impedance between the signal source and the load, reducing reflection, and improving the power transmission efficiency), frequency selection (selecting a specific frequency signal from numerous frequencies), and frequency adjustment (adjusting the resonance frequency), etc. It should also be noted that in a cavity antenna, tuning is used to generate a strong resonance at a specific frequency at the slot in the cavity to radiate electromagnetic waves of a specific frequency outward through the slot, which is a relatively mature technology in this field. Therefore, this embodiment does not elaborate too much on the radiation principle of the first electromagnetic wave / second electromagnetic wave.

[0028] It can be understood that the present embodiment adopts the size optimization based on the fractional multiple of the wavelength (for example, the length of the target long side is set to 1 / n of the wavelength of the first frequency, the target distance between the feeding component 3 and the end point of the target short side away from the ground feeding component 4 is equal to 1 / n of the wavelength of the second frequency, and the length of the target short side is less than or equal to twice the target distance, etc.), so as to accurately control the size of the resonant cavity 9. Taking n=4 as an example, the length of the target long side is about as low as 28 mm, and the length of the target short side is about as low as 26 mm. Compared with the cavity antenna of the traditional solution (cavity length is about 45~65 mm, width is about 25~40 mm), the overall volume can be reduced by 30~50%, and in electronic devices with strict space requirements (such as mobile phones, tablet computers, etc.), it can greatly save internal space and provide more flexibility for the layout of other components. In addition, in the present embodiment, a first tuning circuit 5 and a second tuning circuit 6 are provided to tune the radio frequency signals of the first frequency and the second frequency respectively, thereby ensuring that signals of each frequency band in the miniaturized resonant cavity 9 can effectively excite strong resonance (that is, the first tuning circuit 5 enables the first radiation slot 21 to accurately form a strong resonance of the first frequency, and the second tuning circuit 6 enables the second radiation slot 22 to stably generate a strong resonance of the second frequency), thereby avoiding mutual interference of dual-band signals, so that the radiation efficiency of the antenna can still be maintained at a high level when working in multiple frequency bands. Compared with the cavity antenna with single-frequency radiation in the dual-frequency application scenario in the traditional scheme, the performance is significantly improved; the first radiation slot 21 and the second radiation slot 22 of the present embodiment are respectively located on the target long side and the target short side of the metal cover 2, and the strong electric field area at the junction of the two is used for feeding and grounding, which cleverly feeds the electric field to the ground. The magnetic energy is concentrated and guided to the gaps (the first radiation gap 21 and the second radiation gap 22) for radiation. This design can make the radiation pattern of the antenna more directional and form a strong signal coverage in the direction perpendicular to the long side and the short side of the target, so that the gain is improved. The resonant cavity 9 of this embodiment is filled with air medium. The air has a stable and low dielectric constant (approximately equal to 1), which can ensure that the drift of the resonant frequency of the antenna at different ambient temperatures is extremely small. This makes it unnecessary to calibrate the antenna frequently. The antenna can always maintain accurate frequency response and high-performance output during long-term use, thereby reducing the risk of signal attenuation or loss of connection due to frequency deviation. At the same time, the good heat dissipation performance of the air can promptly take away the heat generated by the antenna when it is working, which can avoid damage to the electronic components in the antenna due to overheating, extend the service life, and reduce maintenance costs.

[0029] As can be seen from the above, through innovative structural design, precise frequency tuning, and reasonable size optimization, this embodiment can not only effectively reduce the volume of the antenna and lower its cost, but also comprehensively ensure the high performance of the antenna in multi-band communication. It truly balances the volume, cost, and performance of the antenna, providing a reliable and efficient solution for the wireless communication of electronic devices. Verified by experiments, the average efficiency of the antenna in this embodiment at 2.4 GHz / 5 GHz is -6 dB, which is better than the traditional solution.

[0030] In some embodiments, please refer to Figure 3 , Figure 3 which is a schematic structural diagram of the miniaturized cavity antenna from another perspective. The metal cover 2 includes a metal top plate 23, a long metal side plate 24, and a short metal side plate 25. The metal top plate 23 includes two opposite long sides and two opposite short sides. One side of the long metal side plate 24 and the short metal side plate 25 are respectively disposed on an adjacent long side and a short side. The other sides of the long metal side plate 24 and the short metal side plate 25 are both disposed on the circuit board 1. The long metal side plate 24 is connected to the short metal side plate 25. The other long side and the other short side of the metal top plate 23 are respectively used as the target long side and the target short side described above. The opening formed between the feeding and grounding component 4 and the short metal side plate 25 is the first radiation slot 21, and the opening formed between the feeding and grounding component 4 and the long metal side plate 24 is the second radiation slot 22.

[0031] As at least one of the embodiments, please refer to Figure 4 , Figure 4 which is Figure 2 a partial enlarged view of B in ; the long metal side plate 24 and the short metal side plate 25 have the same structure, and both include a connecting plate 251 that bends and extends from the metal top plate 23 to the circuit board 1 and a supporting plate 252 that bends and extends from the connecting plate 251 to the circuit board 1. Similarly, please refer to Figure 5 , Figure 5 which is Figure 1 a partial enlarged view of A in ; the feeding component 3 and the feeding and grounding component 4 have the same structure, and both include an extension part 41 that bends and extends from the metal top plate 23 to the circuit board 1 and a connecting part 42 that bends and extends from the extension part 41 to the circuit board 1.

[0032] In some embodiments, please refer to Figures 1 to 3 . In addition to the structure described above, the miniaturized cavity antenna further includes a coaxial cable 8 and a coaxial connector 7. The coaxial connector 7 is disposed on the circuit board 1 and is electrically connected to the feeding component 3 through a second tuning circuit 6. One end of the coaxial cable 8 is electrically connected to the coaxial connector 7, and the other end is used to be electrically connected to a radio frequency circuit. It can be understood that the purpose of setting the coaxial connector 7 and the coaxial cable 8 is to transmit radio frequency signals, and the coaxial cable 8 generally uses 50 Ω.

[0033] Please refer toFigure 6 and Figure 7 , Figure 6 is a schematic structural diagram of an electronic device, Figure 7 is an exploded schematic diagram of the electronic device. This embodiment provides an electronic device, which includes an electronic device body 10 and the miniaturized cavity antenna described above. A main board 101 is provided inside the electronic device body 10, and a radio frequency circuit is provided on the main board 101. The miniaturized cavity antenna is disposed inside the electronic device body 10, and the feeding component 3 in the miniaturized cavity antenna is electrically connected to the radio frequency circuit on the main board 101, that is, the metal cover 2 in the miniaturized cavity antenna is electrically connected to the radio frequency circuit on the main board 101 through the feeding component 3, the second tuning circuit 6, the coaxial socket 7 and the coaxial cable 8 in sequence. The length, width and thickness directions of the miniaturized cavity antenna are the same as those of the electronic device body 10 respectively. Preferably, the miniaturized cavity antenna is located at a corner inside the electronic device body 10. In addition, it should be noted that the electronic device body 10 generally includes a housing 102 and a screen 103 that are docked with each other, and the housing 102 is preferably a full-metal housing. It should also be noted that the electronic device in this embodiment can be any device that commonly requires a cavity antenna to achieve wireless communication in the art, such as a mobile phone, a drone, a tablet computer, a satellite phone, a laptop computer, etc., which can be specifically selected according to actual needs, and this embodiment does not make a unique limitation thereto.

[0034] The above embodiments are only preferred implementations of the present application, and they are not the only limitations on the miniaturized cavity antenna and related electronic devices; in this regard, those skilled in the art can flexibly set them according to the actual application scenarios based on the above embodiments. It can be understood that, through the implementation of the above embodiments of the present application, the size optimization based on the fractional multiple of the wavelength is realized (for example, the length of the target long side is set to 1 / n of the wavelength of the first frequency, the target distance between the feeding component 3 and the end point of the target short side away from the ground feeding component 4 is equal to 1 / n of the wavelength of the second frequency, and the length of the target short side is less than or equal to twice the target distance, etc.), thereby accurately controlling the size of the resonant cavity 9. Taking n=4 as an example, the length of the target long side is about as low as 28mm, and the length of the target short side is about as low as 26mm. Compared with the cavity antenna of the traditional solution (cavity length is about 45~65mm, width is about 25~40mm), the overall volume can be reduced by 30~50%, and in electronic devices with strict space requirements (such as mobile phones, tablets, etc.), it can greatly save internal space and provide more flexibility for the layout of other components. In addition, the present application sets a first tuning circuit 5 and a second tuning circuit 6 to tune the radio frequency signals of the first frequency and the second frequency respectively, ensuring that the signals of each frequency band in the miniaturized resonant cavity 9 can effectively excite strong resonance (that is, the first tuning circuit 5 makes the first radiation slot 21 accurately form a strong resonance of the first frequency, and the second tuning circuit 6 makes the second radiation slot 22 stably generate a strong resonance of the second frequency), avoiding mutual interference of dual-band signals, so that the radiation efficiency of the antenna can still be maintained at a high level when working in multiple frequency bands. Compared with the cavity antenna with single-frequency radiation in the dual-frequency application scenario in the traditional scheme, the performance is significantly improved; the first radiation slot 21 and the second radiation slot 22 in the present application are respectively located on the target long side and the target short side of the metal cover 2, and the strong electric field area at the junction of the two is used for feeding and grounding, and the electromagnetic energy is cleverly concentrated and guided to the slot for radiation. This design can make the radiation pattern of the antenna more directional, and form a strong signal coverage perpendicular to the target long side and the target short side, so that the gain can be improved. It can be seen that the present application can reduce the size of the antenna and reduce its cost while ensuring the performance of the antenna. It truly strikes a balance between the size, cost and performance of the antenna and can provide a reliable and efficient solution for wireless communications of electronic devices.

[0035] It should be noted that several embodiments shown above in this application are described in a progressive manner. Each embodiment focuses on the differences from other embodiments, and the same or similar parts among the embodiments can be referred to each other. It should also be noted that in the textual description of this application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply the existence of such an actual relationship or order between these entities or operations. Further, the term "comprise", "include" or any other corresponding variant is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes these elements, but may also include other elements not explicitly listed, or may also include elements inherent in such a process, method, article or device; moreover, without more limitations, an element defined by the statement "including one..." does not exclude the existence of another identical element in the process, method, article or device including the said element.

[0036] In addition, by implementing several embodiments shown above in this application, those skilled in the art can implement or use this application. For the several embodiments shown above in this application, various modifications will be obvious to those skilled in the art. The general principles defined in this application can be implemented in other embodiments not shown without departing from the spirit or scope of this application. Therefore, this application will not be limited to the several embodiments shown above, but will conform to the broadest scope consistent with the principles and novel features disclosed in this application.

Claims

1. A miniaturized cavity antenna, characterized in that, For radiating a first electromagnetic wave of a first frequency and / or a second electromagnetic wave of a second frequency, it includes a circuit board, a metal cover, a feeding component, a grounding component, a first tuning circuit and a second tuning circuit disposed on the circuit board. The metal cover covers the circuit board and encloses a resonant cavity with the circuit board. The metal cover has a first radiation slot and a second radiation slot which are respectively located on a target long side and a target short side where the metal cover is joined. The length of the target long side is 1 / n of the wavelength of the first frequency and n≥3. The junction of the target long side and the target short side is a strong electric field region. One end of the grounding component is disposed on the metal cover and located at the center of the strong electric field region, and the other end is disposed on the circuit board and grounded through the first tuning circuit. One end of the feeding component is disposed on the target short side, and the other end is disposed on the circuit board and is used for electrically connecting to an external radio frequency circuit through the second tuning circuit. The target distance between the feeding component and the end point of the target short side away from the grounding component is 1 / n of the wavelength of the second frequency, and the length of the target short side is less than or equal to twice the target distance; The radio frequency circuit is used for feeding a radio frequency signal of the first frequency and / or the second frequency into the resonant cavity to excite an electromagnetic field; the first tuning circuit is used for tuning the radio frequency signal to the first frequency, so as to form a strong resonance of the first frequency at the first radiation slot, and radiate the first electromagnetic wave through the first radiation slot; The second tuning circuit is used for tuning the radio frequency signal to the second frequency, so as to form a strong resonance of the second frequency at the second radiation slot, and radiate the second electromagnetic wave through the second radiation slot.

2. The miniaturized cavity antenna according to claim 1, characterized in that, The metal cover includes a metal top plate, a long metal side plate and a short metal side plate. The metal top plate includes two opposite long sides and two opposite short sides. One side of the long metal side plate and the short metal side plate are respectively disposed on one of the joined long side and one of the joined short side. The other sides of the long metal side plate and the short metal side plate are both disposed on the circuit board. The other long side and the other short side are respectively the target long side and the target short side. The first radiation slot is between the grounding component and the short metal side plate, and the second radiation slot is between the grounding component and the long metal side plate.

3. The miniaturized cavity antenna according to claim 2, characterized in that, The long metal side plate and the short metal side plate have the same structure, and both include a connecting plate bent and extended from the metal top plate towards the circuit board and a supporting plate bent and extended from the connecting plate towards the circuit board.

4. The miniaturized cavity antenna according to claim 2, characterized in that, The feeding component and the grounding component have the same structure, and both include an extension part bent and extended from the metal top plate towards the circuit board and a connecting part bent and extended from the extension part towards the circuit board.

5. The miniaturized cavity antenna according to claim 1, wherein It further includes a coaxial cable and a coaxial cable socket disposed on the circuit board and electrically connected to the feeding component. One end of the coaxial cable is electrically connected to the coaxial cable socket, and the other end is used for electrically connecting to the radio frequency circuit.

6. The miniaturized cavity antenna according to claim 1, characterized in that The first frequency is 2.4 GHz, and the second frequency is 5 GHz.

7. The miniaturized cavity antenna according to claim 6, characterized in that, The length of the target long side is 25 to 35 mm, and the length of the target short side is 20 to 30 mm.

8. The miniaturized cavity antenna according to claim 7, characterized in that, The length of the target long side is 28 ± 2 mm, and the length of the target short side is 26 ± 2 mm.

9. The miniaturized cavity antenna according to claim 1, characterized in that The resonant cavity is filled with an air medium.

10. An electronic device, characterized in that, It includes an electronic device body and the miniaturized cavity antenna described in any one of claims 1 to 9. A main board is provided inside the electronic device body, a radio frequency circuit is provided on the main board, the miniaturized cavity antenna is provided inside the electronic device body, the feeding component in the miniaturized cavity antenna is electrically connected to the radio frequency circuit, and the length, width, and thickness directions of the miniaturized cavity antenna are respectively consistent with the length, width, and thickness directions of the electronic device body.

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