Cavity antenna, multilayer circuit board structure and electronic equipment

Abstract

The embodiment of the invention provides a cavity antenna, a multilayer circuit board structure and electronic equipment, the cavity antenna comprises a conductive plate, a connecting plate and a first circuit board which are sequentially connected along a first direction, the connecting plate is provided with a hollow cavity, and the hollow cavity penetrates through two side walls of the connecting plate along the first direction; one of the conductive plate and the first circuit board is provided with an opening, the opening is communicated with the hollow cavity, and the conductive plate, the connecting plate and the first circuit board form a cavity with an opening. According to the cavity antenna provided by the embodiment of the invention, the cavity is located between the conductive plate and the first circuit board, the opening of the cavity antenna is formed in the conductive plate or the first circuit board, the cavity antenna is integrated in the conductive plate, the connecting plate and the first circuit board, the rest space in the electronic equipment is not occupied, the arrangement of other parts in the electronic equipment is not influenced, and the electronic equipment is more convenient to use. And miniaturization development of electronic equipment is realized.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of antenna design, and in particular to a cavity antenna, a multilayer circuit board structure and an electronic device. BACKGROUND

[0002] With the continuous development of communication technology, electronic devices such as mobile phones and tablets have developed from carrying simple functions to supporting voice, data, music, video and other rich media, and can also be extended to install various applications APP to meet people's various needs.

[0003] At the same time, the production and manufacturing process is constantly improving, and consumers are increasingly concerned about the appearance and size of electronic devices, so that electronic devices are constantly developing towards miniaturization, intelligence, thinness and narrow frame. The development of electronic devices tends to be small, which affects the setting space of the antenna in the electronic device, and the setting of the antenna needs to occupy as little space as possible in the electronic device. SUMMARY

[0004] The present disclosure provides a cavity antenna, a multilayer circuit board structure and an electronic device to solve the deficiencies in the related art.

[0005] In a first aspect, the present disclosure provides a cavity antenna, comprising: a conductive plate, a connecting plate and a first circuit board connected in sequence along a first direction, the connecting plate having a hollow cavity, the hollow cavity penetrating through both side walls of the connecting plate along the first direction; one of the conductive plate and the first circuit board is provided with an opening, the opening being in communication with the hollow cavity, the conductive plate, the connecting plate and the first circuit board forming a cavity with the opening.

[0006] Optionally, the conductive plate is a second circuit board, and the connecting plate is an interposer.

[0007] Optionally, the interposer includes a solid area and a hollow area, the hollow area corresponding to the hollow cavity;

[0008] The first circuit board is provided with a first electronic device corresponding to the solid area, and the second circuit board is provided with a second electronic device corresponding to the solid area, and the first electronic device and the second electronic device can be selectively electrically connected through the interposer.

[0009] Optionally, the first circuit board is provided with a third electronic device corresponding to the hollow area, and the third electronic device is electrically connected to the interposer through a first connecting line; the second circuit board is provided with a fourth electronic device corresponding to the hollow area, and the fourth electronic device is electrically connected to the interposer through a second connecting line;

[0010] At least one of the first electronic device and the third electronic device is electrically connectable to at least one of the second electronic device and the fourth electronic device through the interposer.

[0011] Optionally, the conductive plate is arranged towards a non-metal region of the electronic device, the opening is formed in the conductive plate, and the opening corresponds to the non-metal region.

[0012] Optionally, a projection area of the opening on the conductive plate or the first circuit board is a first projection area, a projection area of the hollow cavity on the conductive plate or the first circuit board is a second projection area, and the first projection area is located in the second projection area.

[0013] Optionally, the opening corresponds to a middle position of the hollow cavity.

[0014] Optionally, the shape of the opening is configured such that, when the current of the cavity antenna flows along the edge of the opening, equivalent capacitances are generated between oppositely arranged edge segments of the plurality of edge segments of the opening, for filtering resonance formed by equivalent inductances generated by a portion of the conductive plate or the first circuit board corresponding to the hollow cavity.

[0015] Optionally, the opening includes a first opening and a second opening that are in communication with each other, the first opening and the second opening are both rectangular, and the extension directions of the first opening and the second opening are perpendicular.

[0016] Optionally, the opening is cross-shaped, and a center position of the first opening and a center position of the second opening are in communication.

[0017] Optionally, the cavity antenna further includes a feeding point, and the feeding point is electrically connected to the conductive plate or the first circuit board on which the opening is located.

[0018] In a second aspect, the embodiments of the present disclosure provide a multi-layer circuit board structure, including: a first circuit board, an interposer, and a second circuit board connected in sequence along a first direction, the interposer having a hollow cavity, the hollow cavity penetrating through two side walls of the interposer along the first direction; one of the first circuit board and the second circuit board is provided with an opening, the opening is in communication with the hollow cavity; the first circuit board, the interposer, and the second circuit board enclose a cavity antenna having the opening.

[0019] In a third aspect, the embodiments of the present disclosure provide an electronic device, the electronic device including the cavity antenna or the multi-layer circuit board structure.

[0020] Optionally, the electronic device further comprises a housing having a non-metal region; the opening is arranged corresponding to the non-metal region.

[0021] The technical solutions provided by the embodiments of the present disclosure can include the following beneficial effects:

[0022] As can be seen from the above disclosed embodiments, the cavity antenna of the present disclosure has the hollow cavity in the connecting plate between the conductive plate and the first circuit board, the hollow cavity penetrates through the two side walls of the connecting plate along the first direction, the two ends of the hollow cavity are the conductive plate and the first circuit board respectively, and one of the conductive plate and the first circuit board is provided with an opening, so that the conductive plate, the connecting plate and the first circuit board form a cavity antenna with an opening. The cavity of the cavity antenna provided by the embodiments of the present disclosure is located between the conductive plate and the first circuit board, and the opening of the cavity antenna provided by the embodiments of the present disclosure is arranged in the conductive plate or the first circuit board. The cavity antenna is integrated in the conductive plate, the connecting plate and the first circuit board, without occupying the remaining space in the electronic device, and does not affect the arrangement of other components in the electronic device, so as to realize the miniaturization development of the electronic device.

[0023] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present disclosure. BRIEF DESCRIPTION OF DRAWINGS

[0024] The accompanying drawings, which are incorporated into and form part of the specification, illustrate embodiments consistent with the present disclosure and, together with the specification, serve to explain the principles of the present disclosure.

[0025] Figure 1 is a structural schematic diagram of a cavity antenna according to an exemplary embodiment;

[0026] Figure 2 is a top view of a cavity antenna according to an exemplary embodiment;

[0027] Figure 3 is a structural schematic diagram of an opening of a cavity antenna according to an exemplary embodiment;

[0028] Figure 4 is a top view of a cavity antenna according to another exemplary embodiment;

[0029] Figure 5 is an antenna efficiency diagram of a cavity antenna obtained by simulation according to an exemplary embodiment;

[0030] Figure 6 is an antenna reflection coefficient diagram of a cavity antenna obtained by simulation according to an exemplary embodiment;

[0031] Figure 7FIG. 1 is a structural schematic diagram of a cavity antenna 1 according to an example embodiment.

[0032] Reference signs:

[0033] Cavity antenna 1, multilayer circuit board structure 2, conductive plate 10, connecting plate 20, first circuit board 30, radiator 31, hollow cavity 40, opening 50, feed point 60, second circuit board 11, interlayer 21, solid region 211, hollow region 212, first projection region 54, second projection region 41, edge section 51, first edge section 511, second edge section 512, third edge section 513, fourth edge section 514, fifth edge section 515, sixth edge section 516, seventh edge section 517, eighth edge section 518, first opening 52, second opening 53. DETAILED DESCRIPTION

[0034] The technical solutions in the embodiments (or, implementations) of the present disclosure will be described clearly and completely in conjunction with the drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated.

[0035] If the present disclosure involves terms related to directionality or positional relationship (for example, up, down, left, right, front, back, inner, outer, top, bottom, center, vertical, horizontal, longitudinal, transverse, length, width, counterclockwise, clockwise, axial, radial, circumferential, etc.), such terms are only used to explain the relative position relationship, movement, etc. between the components in a certain posture (as shown in the drawings). If the specific posture changes, the directionality or positional relationship will also change accordingly. In addition, the terms "first", "second", etc. in the present disclosure are only used for convenience of description, and cannot be understood as indicating or implying relative importance.

[0036] Referring to Figure 1 and Figure 2 shown, Figure 1 is a structural schematic diagram of a cavity antenna 1 according to an example embodiment, Figure 2 is a top view of the cavity antenna 1 according to an example embodiment.

[0037] The present disclosure provides a cavity antenna 1, which can be applied to electronic devices such as mobile phones, tablets, laptops, smart glasses, smart watches, smart bracelets, wearable devices, etc.

[0038] The cavity antenna 1 provided by the present disclosure can be a millimeter wave antenna, or a Bluetooth antenna, a WiFi antenna, an NFC antenna, a 4G antenna, a 5G antenna, etc.

[0039] The cavity antenna 1 comprises: a conductive plate 10, a connecting plate 20 and a first circuit board 30 connected in sequence along a first direction (Z direction), the connecting plate 20 has a hollow cavity 40, the hollow cavity 40 penetrates through two side walls of the connecting plate 20 along the first direction. One of the conductive plate 10 and the first circuit board 30 is provided with an opening 50, the opening 50 is communicated with the hollow cavity 40, and the conductive plate 10, the connecting plate 20 and the first circuit board 30 form a cavity antenna 1 with the opening 50.

[0040] Optionally, the opening 50 can be a slit or a slot. It can be understood that the hollow cavity 40 can be formed by hollowing out the connecting plate 20 by using a cavity process, and the opening 50 can be formed on the conductive plate 10 or the first circuit board 30. The cavity process is a process for creating a local recess or cavity on a printed circuit board during the process of the printed circuit board, and the process is mature and has good processing stability.

[0041] In the embodiment, the conductive plate 10, the connecting plate 20 and the first circuit board 30 are all plate structures, the first direction is the Z direction in the formula Figure 1 , which is also the thickness direction of the conductive plate 10, the connecting plate 20 and the first circuit board 30. The X direction can be one of the length direction or the width direction of the conductive plate 10, the connecting plate 20 and the first circuit board 30, and the Y direction is the other one of the length direction or the width direction of the conductive plate 10, the connecting plate 20 and the first circuit board 30.

[0042] In the embodiment, the conductive plate 10, the connecting plate 20 and the first circuit board 30 are connected in sequence along the first direction, that is, the conductive plate 10, the connecting plate 20 and the first circuit board 30 are connected in sequence along the thickness direction thereof, and in some optional embodiments, the first direction is also the thickness direction of the electronic device. In the embodiment shown in the formula Figure 1 , the opening 50 is arranged on the conductive plate 10, and in some other embodiments, the opening 50 is arranged on the first circuit board 30.

[0043] As can be seen from the above embodiment, the cavity antenna 1 of the present disclosure has the hollow cavity 40 in the connecting plate 20 between the conductive plate 10 and the first circuit board 30, the hollow cavity 40 penetrates through two side walls of the connecting plate 20 along the first direction (Z direction), the two ends of the hollow cavity 40 are respectively the conductive plate 10 and the first circuit board 30, one of the conductive plate 10 and the first circuit board 30 is provided with the opening 50, so that the conductive plate 10, the connecting plate 20 and the first circuit board 30 form a cavity antenna 1 with the opening 50. The hollow cavity 40 can be used as the cavity of the cavity antenna 1, and the opening 50 can be used as the opening of the radiation current of the cavity antenna 1.

[0044] The cavity of the cavity antenna 1 is located between the conductive plate 10 and the first circuit board 30, and the opening 50 of the cavity antenna 1 is arranged on the conductive plate 10 or the first circuit board 30, so that the cavity antenna 1 is integrated in the conductive plate 10, the connecting plate 20 and the first circuit board 30. The cavity and the opening 50 only occupy the space of the conductive plate 10, the connecting plate 20 and the first circuit board 30, do not occupy the remaining space in the electronic device, do not affect the arrangement of other components in the electronic device, and are convenient for saving the space of the electronic device and miniaturizing the electronic device.

[0045] In some optional embodiments, the conductive plate 10 is a second circuit board, and the connecting plate 20 is an interposer. The second circuit board, the interposer and the first circuit board 30 form a multi-layer circuit board structure, and the conductive plate 10, the connecting plate 20 and the first circuit board 30 can form a three-layer circuit board structure by pressing. Alternatively, the second circuit board can be a radio frequency board, and electronic components can be arranged on the second circuit board. It can be understood that in the multi-layer circuit board structure, the interposer plays a crucial role. The interposer is located between the first circuit board 30 and the second circuit board, not only can support the first circuit board 30 and the second circuit board, but also can realize power transmission and signal transmission through the interposer, so as to facilitate the electrical connection between the electronic components on the first circuit board 30 and the second circuit board.

[0046] In some optional embodiments, the cavity process can be used to hollow the interposer to form a hollow area 212, so that the interposer includes a solid area 211 and a hollow area 212, and the hollow area 212 corresponds to the hollow cavity 40.

[0047] The first circuit board 30 is provided with a first electronic component corresponding to the solid area 211, and the second circuit board is provided with a second electronic component corresponding to the solid area 211, and the first electronic component and the second electronic component can be selectively electrically connected through the interposer.

[0048] When the first electronic component located on the first circuit board 30 needs to be electrically connected with the second electronic component located on the second circuit board, the electrical connection can be realized through the solid area 211. Specifically, the interposer connection line is distributed in the solid area 211, and the electrical connection between the first electronic component and the second electronic component can be realized through the interposer connection line of the solid area 211.

[0049] In the multi-layer circuit board structure, in addition to the interposer connection line distributed in the interposer, a first connection line is distributed on the first circuit board 30, and a second connection line is distributed on the second circuit board. The interposer connection line, together with the first connection line and the second connection line, constitutes a circuit network of the multi-layer circuit board.

[0050] The first circuit board 30 is provided with a third electronic device corresponding to the hollow region 212, and the third electronic device is electrically connected with the interlayer through the first connecting line. The second circuit board is provided with a fourth electronic device corresponding to the hollow region 212, and the fourth electronic device is electrically connected with the interlayer through the second connecting line.

[0051] The first electronic device and the third electronic device located on the first circuit board 30 can be electrically connected through the first connecting line of the first circuit board 30, and the second electronic device located on the second circuit board and the fourth electronic device located on the second circuit board can be electrically connected through the second connecting line of the second circuit board.

[0052] At least one of the first electronic device and the third electronic device can be selectively electrically connected with at least one of the second electronic device and the fourth electronic device through the interlayer. It can be understood that the first electronic device can be electrically connected with the second electronic device through the interlayer connecting line of the interlayer. The first electronic device can also be electrically connected with the fourth electronic device through the interlayer connecting line of the interlayer, the second connecting line of the second circuit board.

[0053] The third electronic device can be electrically connected with the second electronic device through the first connecting line of the first circuit board 30, the interlayer connecting line of the interlayer, and can also be electrically connected with the fourth electronic device through the first connecting line of the first circuit board 30, the interlayer connecting line of the interlayer, and the second connecting line of the second circuit board.

[0054] The electronic devices of the first circuit board 30 and the second circuit board, whether corresponding to the solid region 211 or corresponding to the hollow region 212, can be electrically connected through one or a combination of the interlayer connecting line, the first connecting line and the second connecting line. Therefore, the hollow region 212 provided in the interlayer serves as the cavity of the cavity antenna 1, and does not affect the connection between the electronic devices provided on the original multi-layer circuit board. The opening 50 formed on the first circuit board 30 or the second circuit board occupies part of the space of the first circuit board 30 or the second circuit board, but because the opening 50 is generally not very large, compared with the separately provided cavity antenna, the cavity antenna 1 is integrated between the first circuit board 30, the interlayer and the second circuit board, which effectively saves the space inside the electronic device and facilitates the miniaturization of the electronic device.

[0055] Please refer to Figure 2 , the projection area of the opening 50 on the conductive plate 10 or the first circuit board 30 is a first projection area 54, the projection area of the hollow cavity 40 on the conductive plate 10 or the first circuit board 30 is a second projection area 41, the first projection area 54 is located in the second projection area 41, and the second projection area 41 is Figure 2The first projection area 54 is located in the area enclosed by the dashed line in the middle of the hollow cavity 40, and the area of the first projection area 54 is smaller than the area of the second projection area 41. It can be understood that on the conductive plate 10 where the opening 50 is located or on the first circuit board 30 where the opening 50 is located, the end of the hollow cavity 40 includes the opening 50 and the unopened area, which can serve as the radiator 31 of the cavity antenna 1 to radiate the radiation current flowing out of the opening 50 of the cavity antenna 1 outward.

[0056] In this embodiment, the opening 50 corresponds to the middle position of the hollow cavity 40. In this way, not only can the processing difficulty be reduced and the aesthetics of the cavity antenna 1 be improved, but also the radiation directivity can be affected and the gain of the antenna can be further improved.

[0057] The hollow cavity 40 serves as a resonance cavity and can enhance the radiation capability of electromagnetic waves. When electromagnetic waves are input into the cavity, the intensity of the electromagnetic waves is amplified through resonance, thereby improving the radiation efficiency of the antenna. The shape and structure of the cavity can affect the radiation directivity of the antenna. By designing cavities of different shapes, the control of the radiation direction of the antenna can be realized, so that the antenna has stronger radiation capability in a specific direction.

[0058] The size and shape of the cavity determine its resonance frequency. By adjusting the size of the cavity, different resonance frequencies can be obtained, thereby realizing the radiation or reception of electromagnetic waves of a specific frequency. Generally, when it is necessary to increase the frequency of electromagnetic waves, the size of the cavity can be adaptively reduced, and when it is necessary to reduce the frequency of electromagnetic waves, the size of the cavity can be adaptively increased.

[0059] The opening 50 is the main channel for the cavity antenna 1 to radiate electromagnetic waves. After the electromagnetic waves are resonated and enhanced in the cavity, they are radiated outward through the opening 50. The shape, size and position of the opening 50 will affect the radiation characteristics of the antenna, including the radiation directivity and the gain.

[0060] The design of the opening 50 can be used to adjust the impedance matching of the antenna. By changing the shape, size and position of the opening 50, the input impedance of the antenna can be optimized to better match the feed network or transmission line, reducing signal reflection and loss. The opening 50 can also be used to improve the operating frequency range of the antenna. By adjusting the size and shape of the opening 50, the resonance frequency of the antenna can be fine-tuned to expand the operating bandwidth of the antenna. Generally, by adjusting the size and shape of the opening 50 to increase the electrical length of the radiation current, the resonance frequency of the antenna can be shifted to a lower frequency point. By adjusting the size and shape of the opening 50 to reduce the electrical length of the radiation current, the resonance frequency of the antenna can be shifted to a higher frequency point.

[0061] Please refer to Figure 3 , Figure 3 The structure of the opening of the cavity antenna according to an exemplary embodiment is shown. InFigure 3 In the illustrated embodiment, the edge of the opening 50 includes multiple edge segments 51. When the current of the cavity antenna 1 flows along the edge of the opening 50, an equivalent capacitance is generated between the opposing edge segments 51 of the multiple edge segments 51 of the opening 50. This capacitance is used to form a resonance with the equivalent inductance generated by the conductive plate 10 or the portion of the first circuit board 30 corresponding to the hollow cavity 40, thereby performing filtering. In this embodiment, the opening 50 can be cross-shaped, L-shaped, or other shapes, and this disclosure does not limit this.

[0062] Because current flows through the opposing edge segments 51, charge accumulates, and the air medium in the small space between the edge segments 51 forms a non-conductive insulating medium, which can constitute an equivalent capacitor.

[0063] The portion of the conductive plate 10 or the first circuit board 30 where the opening 50 is located, corresponding to the hollow cavity 40, generates an equivalent inductance. Figure 3 In the illustrated embodiment, the opening 50 is formed in the conductive plate 10, which corresponds to the portion of the hollow cavity 40, i.e. Figure 3 The portion between the outer frame of the second projection area 41 (the dashed frame in the figure) and the opening 50, i.e., the radiator 31, generates an equivalent inductance. The equivalent capacitance and equivalent inductance combined can form a resonant circuit for filtering. When electromagnetic waves or current pass through the cavity antenna 1, the resonant circuit will produce a strong response to waves of a specific frequency, resulting in resonance, while the response to waves of other frequencies will be relatively weak, thereby improving the filtering effect of the antenna.

[0064] exist Figure 3 In the illustrated embodiment, the opening 50 includes a first opening 52 and a second opening 53 that are interconnected. Both the first opening 52 and the second opening 53 are rectangular, and their extending directions are perpendicular. This arrangement facilitates the processing of the opening 50, and the rectangular structure includes opposing edge segments 51.

[0065] In this embodiment, the center of the first opening 52 is connected to the center of the second opening 53, and the opening 50 is cross-shaped. The plurality of edge segments 51 include a first edge segment 511, a second edge segment 512, a third edge segment 513, a fourth edge segment 514, a fifth edge segment 515, a sixth edge segment 516, a seventh edge segment 517, and an eighth edge segment 518. Specifically, the first edge segment 511 and the second edge segment 512 are oppositely arranged edge segments 51; the third edge segment 513 and the fourth edge segment 514 are oppositely arranged edge segments 51; the fifth edge segment 515 and the sixth edge segment 516 are oppositely arranged edge segments 51; and the seventh edge segment 517 and the eighth edge segment 518 are oppositely arranged edge segments 51. These four pairs of oppositely arranged edge segments 51 can form four identical equivalent capacitances that are superimposed.

[0066] In some optional embodiments, the first opening 52 and the second opening 53 are communicated with each other at their ends, and the opening 50 is L-shaped. Among the plurality of edge segments 51 of the L-shaped opening 50, two sets of oppositely arranged edge segments can be included, and two equivalent capacitances can be formed to be superimposed.

[0067] In some specific embodiments, the hollow cavity 40 is a cubic structure, the length L1 of the side of the second projection area 41 of the conductive plate 10 is 8.1 mm, the distance L2 between the oppositely arranged edge segments 51 of the cross-shaped opening 50 is 1 mm, the length L3 of the cross-shaped opening 50 in the Y direction is 4 mm, and the length L4 of the cross-shaped opening 50 in the X direction is 4.5 mm. It has been verified through experiments that the cavity antenna with the above dimensions has good filtering performance.

[0068] Please refer to Figure 4 , Figure 4 is a top view of the cavity antenna 1 according to another exemplary embodiment, in which Figure 4 In the embodiment shown in FIG. 6, the cavity antenna 1 further includes a feeding point 60, which is electrically connected to the conductive plate 10 or the first circuit board 30 where the opening 50 is located. The feeding point 60 is arranged close to the opening 50, which can improve the radiation efficiency of the cavity antenna 1. The feeding point 60 is electrically connected to the conductive plate 10 or the first circuit board 30 where the opening 50 is located through conductive foam. In the embodiment shown in FIG. 7, the feeding point 60 is arranged at the lower right corner of the cross-shaped opening 50, and the radiation current flowing out of the opening 50 flows along the edge segments 51 of the opening 50 to the feeding point 60. The overall equivalent current direction of the antenna radiation is shown by the dashed arrow 3 in FIG. 8, forming a single-polarized -45° antenna. Figure 4 Figure 4 In the embodiment shown in FIG. 7, the feeding point 60 is arranged at the lower right corner of the cross-shaped opening 50, and the radiation current flowing out of the opening 50 flows along the edge segments 51 of the opening 50 to the feeding point 60. The overall equivalent current direction of the antenna radiation is shown by the dashed arrow 3 in FIG. 8, forming a single-polarized -45° antenna.

[0069] Please refer to Figure 5 , Figure 5 is an antenna efficiency diagram of the cavity antenna 1 according to an exemplary embodiment obtained by simulation. As shown in FIG. 9, the horizontal coordinate of the efficiency diagram represents the frequency, with the unit of MHz, and the vertical coordinate represents the gain, with the unit of dB. Figure 5 As can be seen from FIG. 10, the frequency coverage range of the antenna is 28 GHz-49 GHz. In the band below 28 GHz, the efficiency of the antenna is concentrated at -25 dB, and in the band of 28 GHz-49 GHz, the efficiency of the antenna is concentrated at -5 dB. It can be known that the out-of-band suppression effect of the antenna provided in the present exemplary embodiment is -30 dB, which has a good filtering effect. Moreover, the efficiency of the antenna provided in the present exemplary embodiment reaches -3 dB, which has a good radiation performance. Figure 5

[0070] Please refer to Figure 6 , Figure 6 ​​The cavity antenna 1 according to an example embodiment is shown in the simulated antenna reflection coefficient diagram. As shown in the figure, the antenna according to the example embodiment has a small reflection coefficient in the wave band of 28GHz-49GHz, that is, the antenna reflects back a small proportion of the signal transmitted, and more signals are radiated, and the antenna has strong radiation performance. Figure 7

[0071] The cavity antenna 1 according to the example embodiment can have the opening 50 formed on the conductive plate 10 or the first circuit board 30, that is, the opening 50 can be formed on one side of the first direction of the hollow cavity 40 or the other side of the first direction of the hollow cavity 40. The cavity antenna 1 can be formed on the conductive plate 10 or the first circuit board 30, but needs to be selected according to the specific circumstances of the electronic device to which the cavity antenna 1 is applied.

[0072] When the cavity antenna 1 is actually applied to an electronic device, the electronic device includes a shell in addition to the cavity antenna 1, and the shell has a non-metal region. At least one of the conductive plate 10 and the first circuit board 30 corresponds to the non-metal region, and the opening 50 is arranged corresponding to the non-metal region. It can be understood that the non-metal region can be a protective back cover of the electronic device. The opening 50 of the cavity antenna 1 is designed to face the protective back cover, which can achieve a better clearance environment, so that the cavity antenna 1 can achieve better antenna radiation performance and filtering performance.

[0073] Metal has good electrical conductivity. When the cavity antenna 1 is surrounded or closely attached to metal, the metal will absorb or reflect the electromagnetic waves emitted by the cavity antenna 1, resulting in a decrease in signal strength or even ineffective transmission. Arranging the opening 50 corresponding to the non-metal region can ensure that the electromagnetic waves can smoothly pass through and radiate to the outside space, thereby avoiding the shielding effect of metal on the signal.

[0074] It can be understood that when the conductive plate 10 is arranged to face the non-metal region of the electronic device, the opening 50 is formed on the conductive plate 10, and the opening 50 corresponds to the non-metal region. When the first circuit board 30 faces the non-metal region, the opening 50 is formed on the first circuit board 30, and the opening 50 corresponds to the non-metal region. When the metal shell has at least two non-metal regions, and the conductive plate 10 and the first circuit board 30 both correspond to the non-metal region, the opening 50 can be formed on the conductive plate 10 or the first circuit board 30. The position of the opening 50 can be selected according to the specific circumstances of the non-metal region of the shell and the layout of the electronic components in the electronic device.

[0075] ​This disclosed cavity antenna utilizes the cavity process in PCB layout to design a cavity millimeter-wave filtering antenna. Without occupying the design space of other frequency band antennas or board traces, it effectively utilizes board space to integrate the millimeter-wave antenna with the entire PCB. Simultaneously, the top of the millimeter-wave antenna faces the protective rear cover, providing excellent clearance. The cavity antenna disclosed herein exhibits excellent antenna radiation and filtering performance in whole-system simulation.

[0076] See Figure 7 As shown, Figure 7 This is a schematic diagram illustrating a multilayer circuit board structure according to an exemplary embodiment. This disclosure also provides a multilayer circuit board structure 2, including a first circuit board 30, an interposer layer 21, and a second circuit board 11 connected sequentially along a first direction. The interposer layer 21 has a hollow cavity 40, which penetrates both side walls of the interposer layer 21 along the first direction. One of the first circuit board 30 and the second circuit board 11 has an opening 50 communicating with the hollow cavity 40. The first circuit board 30, the interposer layer 21, and the second circuit board 11 together form a cavity antenna 1 with the opening 50.

[0077] It should be noted that the description of the cavity antenna 1 in the above embodiments and implementations also applies to the multilayer circuit board structure 2 of this embodiment. It can be understood that the multilayer circuit board structure 2 of this embodiment can be understood as the multilayer circuit board structure composed of the second circuit board, the intermediate layer and the first circuit board 30 when the conductive plate 10 of the cavity antenna 1 is the second circuit board and the connecting plate 20 is the intermediate layer in the above embodiments and implementations.

[0078] In this embodiment, the multilayer circuit board structure 2 has a hollow area in the interposer layer 21, which serves as the cavity for the cavity antenna 1. Integrating the cavity antenna 1 between the first circuit board 30, the interposer layer 21, and the second circuit board 11 fully utilizes the space of the multilayer circuit board structure 2, effectively saving internal space in the electronic device and facilitating miniaturization. Utilizing the cavity technology in PCB layout, a cavity millimeter-wave filter antenna was designed. Without occupying the design space of other frequency band antennas or board-end traces, the millimeter-wave antenna is effectively integrated with the entire PCB by utilizing the board-end space of the multilayer circuit board structure 2. Simultaneously, the top of the millimeter-wave antenna faces the protective rear cover, providing excellent clearance. Under whole-device simulation, the cavity antenna exhibits excellent antenna radiation and filtering performance.

[0079] This disclosure also provides an electronic device, which includes a cavity antenna 1 or a multilayer circuit board structure 2. In some optional embodiments, the electronic device further includes a housing having a non-metallic region, with an opening 50 corresponding to the non-metallic region. Optionally, the electronic device may be a mobile phone, tablet computer, laptop computer, smart glasses, smartwatch, smart bracelet, wearable device, or other electronic devices.

[0080] It should be noted that the descriptions of cavity antenna 1 and multilayer circuit board structure 2 in the above embodiments and implementations are also applicable to the electronic device of this embodiment.

[0081] In the electronic device of this embodiment, the cavity antenna 1 is integrated between the first circuit board 30, the interposer layer 21 and the second circuit board 11, which can make full use of the space of the multi-layer circuit board structure 2, effectively save the internal space of the electronic device, and facilitate the miniaturization and multi-antenna development of the electronic device.

[0082] It should be noted that the technical solutions or features described in the above embodiments can be combined or complemented by each other without conflict. The scope of protection of this disclosure is not limited to the precise structures described in the above embodiments and shown in the accompanying drawings. All modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the scope of protection of this disclosure.

Claims

1. A cavity antenna, characterized in that, include: A conductive plate, a connecting plate, and a first circuit board are sequentially connected along a first direction. The connecting plate has a hollow cavity that extends through both side walls of the connecting plate along the first direction. One of the conductive plate and the first circuit board has an opening that communicates with the hollow cavity. The conductive plate, the connecting plate, and the first circuit board form a cavity with the opening.

2. The cavity antenna according to claim 1, characterized in that, The conductive plate is a second circuit board, and the connecting plate is an intermediary layer.

3. The cavity antenna according to claim 2, characterized in that, The intermediary layer includes a solid region and a hollow region, wherein the hollow region corresponds to the hollow cavity; The first circuit board has a first electronic device corresponding to the physical area, and the second circuit board has a second electronic device corresponding to the physical area. The first electronic device and the second electronic device can be selectively electrically connected through the interposer layer.

4. The cavity antenna according to claim 3, characterized in that, The first circuit board has a third electronic device corresponding to the hollow area, and the third electronic device is electrically connected to the interposer layer through a first connecting line; the second circuit board has a fourth electronic device corresponding to the hollow area, and the fourth electronic device is electrically connected to the interposer layer through a second connecting line. At least one of the first electronic device and the third electronic device can be selectively electrically connected to at least one of the second electronic device and the fourth electronic device through the interposer.

5. The cavity antenna according to claim 1, characterized in that, The conductive plate is disposed facing the non-metallic area of ​​the electronic device, and the opening is formed on the conductive plate and corresponds to the non-metallic area.

6. The cavity antenna according to claim 1, characterized in that, The projection area of ​​the opening on the conductive plate or the first circuit board is the first projection area, and the projection area of ​​the hollow cavity on the conductive plate or the first circuit board where the opening is located is the second projection area, with the first projection area located within the second projection area.

7. The cavity antenna according to claim 1, characterized in that, The opening corresponds to the middle position of the hollow cavity.

8. The cavity antenna according to claim 1, characterized in that, The shape of the opening is configured such that the edge of the opening includes multiple edge segments. When the current of the cavity antenna flows along the edge of the opening, an equivalent capacitance is generated between the opposing edge segments of the multiple edge segments of the opening. This capacitance is used to form a resonance with the equivalent inductance generated by the conductive plate where the opening is located or the portion of the first circuit board corresponding to the hollow cavity for filtering.

9. The cavity antenna according to claim 8, characterized in that, The opening includes a first opening and a second opening that are interconnected. Both the first opening and the second opening are rectangular, and their extension directions are perpendicular.

10. The cavity antenna according to claim 9, characterized in that, The opening is cross-shaped, and the center of the first opening and the center of the second opening are connected.

11. The cavity antenna according to claim 1, characterized in that, The cavity antenna also includes a feed point, which is electrically connected to the conductive plate or the first circuit board where the opening is located.

12. A multilayer circuit board structure, characterized in that, include: A first circuit board, an interposer, and a second circuit board are sequentially connected along a first direction. The interposer has a hollow cavity that extends through both side walls of the interposer along the first direction. One of the first circuit board and the second circuit board has an opening that communicates with the hollow cavity. The first circuit board, the interposer, and the second circuit board together form a cavity antenna with the opening.

13. An electronic device, characterized in that, include: Cavity antenna as described in any one of claims 1-11; or The multilayer circuit board structure as described in claim 12.

14. The electronic device according to claim 13, characterized in that, The electronic device further includes a housing having a non-metallic region; the opening is provided corresponding to the non-metallic region.

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