WO2021135370A1

WO2021135370A1 - Antenna and electronic device

Info

Publication number: WO2021135370A1
Application number: PCT/CN2020/114238
Authority: WO
Inventors: 马国忠; 孙树辉; 刘深鹏; 梁娇; 陈峰文; 邹真林
Original assignee: 华为技术有限公司
Priority date: 2019-12-30
Filing date: 2020-09-09
Publication date: 2021-07-08
Also published as: CN113131182A; CN113131182B

Abstract

Provided are an antenna and an electronic device, relating to the technical field of antennas. The antenna is of a flat-metal-pipeline-type structure with openings at both ends, wherein a top surface of the antenna is set as a grounding reference plane for feeding; the top surface of the antenna is provided with a gap, and the antenna is in an open-circuit state at the gap; and a grounding point is further provided on the top surface. The antenna further comprises a feeding line, wherein the feeding line is arranged inside the antenna; two ends of the feeding line are arranged on two sides of the gap, respectively; one end of the feeding line is provided with a feeding point, and the feeding point and the grounding point form a feeding port; and the other end of the feeding line freely extends. The antenna further comprises a bottom surface arranged opposite the top surface, and the bottom surface can be connected to a metal ground. The antenna in the embodiments of the present application can be arranged on a grounding structural member of an electronic device, such that the problem of insufficient antenna arrangement space in an electronic device can be solved.

Description

An antenna and electronic equipment

Cross-references to related applications

This application claims the priority of a Chinese patent application filed with the Chinese Patent Office with the application number 201911403708.0 and the application name "an antenna and electronic device" on December 30, 2019, the entire content of which is incorporated into this application by reference.

Technical field

This application relates to the field of antenna technology, and in particular to an antenna and electronic equipment.

Background technique

In recent years, in order to meet the needs of the communications market, more and more antennas are used in electronic devices. Especially with the start of 5G communication, 4-8 multi-input-multi-output (MIMO) antennas will be added to the mobile phone.

At present, in order to make antennas have good radiation efficiency, antennas are basically distributed on the edge of electronic equipment. And the middle area inside the body of the electronic device, such as the upper part of the battery, has always been the forbidden area of the antenna. The main reason is that most of the antennas in electronic devices use ground-clearance antennas, such as inverted-F antennas (IFA) and T-shaped antennas. This type of antenna cannot be placed directly on a grounded metal structure. Keep a certain distance between the radiator of the antenna and the grounded metal structure. With the gradual reduction of this distance (clear space), the antenna performance will deteriorate sharply.

Based on the above situation, the space available for antennas in electronic equipment is already insufficient. If multiple antennas are to be added, it will bring great challenges to the antenna design. This is faced with the fact that no suitable place can be found to place these newly added 5G new radio (NR) antennas.

Summary of the invention

The technical solution of the present application provides an antenna and an electronic device to meet the communication requirements of the electronic device.

In the first aspect, the technical solution of the present application provides an antenna, which can be set in a flat metal pipe shape with open ends. The top surface of the antenna pipeline is used as a reference ground for feeding, and a slot is opened on the top surface so that the antenna is in an open state at the slot; a grounding point is also provided on the top surface. In addition, the antenna also has a feeder line, among which: the feeder line is arranged inside the pipe of the antenna, the two ends of the feeder line are arranged on both sides of the gap, one end of the feeder line has a feeding point, and the feeding point and the grounding point form a feeding Port, the other end of the feeder wire extends freely. The antenna further includes a bottom surface disposed opposite to the top surface, and the bottom surface can be connected to the metal ground. Therefore, the antenna of the embodiment of the present application can be arranged on the grounding structure of the electronic device, so as to solve the problem of insufficient space for the antenna in the electronic device. In addition, with the antenna of the embodiment of the present application, by opening a slot on the top surface of the antenna, a closed loop of the same direction current can be formed on both sides of the slot along the surface of the antenna, and the loop current generates the required resonance. The inductance L of the antenna, and the gap on the top surface forms a capacitor C, the resonant frequency of the antenna can be used

It is estimated that the resonant frequency of antenna radiation can be adjusted by adjusting the inductance L generated by the loop current and the capacitor C formed by the gap on the top surface.

In a possible implementation manner of the present application, the antenna further includes a bottom surface disposed opposite to the top surface. When the feeder line is specifically arranged, the feeder line and the top surface are spaced apart, and the feeder line and the bottom surface are spaced apart. In order to realize the coupling feed of the antenna.

In a possible implementation of the present application, when the gap on the top surface is specifically set, the gap divides the top surface into a first area and a second area that have no interconnection relationship. Since the antenna can form a capacitance at the gap, it is possible to tune the capacitance generated at the gap of the antenna by arranging a capacitive device or an inductance device for connecting the first area and the second area at the gap, so as to make the resonant frequency of the antenna Change so that the antenna becomes an adjustable antenna.

In addition, the size of the slot along the direction from the first area to the second area may be set to be not greater than 1 mm, so as to help reduce the size of the antenna and increase the radiation frequency of the antenna.

In a possible implementation of the present application, the extending direction of the slot can be the same as the opening direction of the antenna. In this case, the slot can be set in the middle of the top surface, so that the area of the first area and the second area are equal. Two closed current loops of equal size can be formed on the outer surface of the pipe of the antenna. At this time, the efficiency bandwidth of the antenna is better.

In addition, the gap can also be offset to the top surface, so that the area of the first area and the second area are not equal. At this time, the outer surface of the pipe of the antenna will form two closed current loops of unequal sizes. Two resonances are generated respectively. By adjusting the offset position of the slot on the top surface, the changes of the two resonance frequency points can be tuned, so that the antenna can have dual-frequency characteristics and become a dual-frequency antenna.

In a possible implementation of the present application, the slot can also be opened along the diagonal of the top surface, because the length of the slot opened along the diagonal is longer than the length of the slot provided along the opening direction of the antenna; Only one current loop is formed at the cross section of the opening, and the length of the current loop increases, so that the inductance generated by it also increases. When the capacitance and inductance are both greatly increased, the antenna resonant frequency will be greatly reduced, but it can meet the design requirements of narrowband antennas.

In a possible implementation of the present application, the antenna further includes two sides for connecting the top surface and the bottom surface, and the resonance wavelength of the antenna is λ; when the extending direction of the slot is consistent with the opening direction of the antenna, and the slot is set on the top surface When the gap is in the middle position, the gap between the two sides of the gap is less than or equal to λ/2. In this way, on the surface of the antenna, the antenna forms two loop currents of λ/2. The loop current produces the inductance L required for resonance, and the gap on the top surface forms the capacitance C, and the resonant frequency of the antenna can be used

To estimate.

In a possible implementation manner of the present application, the distance between the top surface and the bottom surface may be less than or equal to 1 mm. In this way, the thin design of the antenna is realized, which is beneficial to the thin design of the electronic device.

In addition, the antenna further includes two side surfaces for connecting the top surface and the bottom surface. The distance H between the top surface and the bottom surface and the distance D between the two side surfaces satisfy the following requirement: H/D≤0.025. By adjusting the height and width of the antenna, it can meet the bandwidth requirements and have higher radiation efficiency.

In a possible implementation of this application, the antenna can also be filled with a medium. In order to make the antenna have better bandwidth characteristics, the dielectric constant of the filling material generally does not exceed 3. At the same time, the smaller the electrical signal loss of the filling material, the more it is good. In addition, the medium filled in the antenna can be a multilayer arranged in a stack, so that the feeder can be arranged between two adjacent layers of the medium, thereby improving the structural stability of the antenna.

In a possible implementation of the present application, the antenna may further include a bottom surface disposed opposite to the top surface, the multilayer dielectric is disposed between the top surface and the bottom surface of the antenna, and the top surface and the bottom surface pass through two rows of via holes penetrating the multilayer dielectric. Contact; the arrangement direction of each row of vias is consistent with the opening direction of the antenna, and the top and bottom surfaces of the two rows of vias enclose the antenna pipeline. The via hole is provided on the dielectric layer as the side wall of the antenna, and the process is easier to control. In addition, by arranging two rows of via holes on the dielectric layer to serve as the two side walls of the antenna, the antenna can have better radiation efficiency.

In a possible implementation of the present application, when each row of vias is specifically arranged, the gap between two adjacent vias may be less than or equal to 0.3 mm. So as to meet the radiation efficiency of the antenna.

In the second aspect, the technical solution of the present application provides an electronic device, which includes the antenna described in the first aspect.

When the antenna is installed in an electronic device, the antenna can be installed in a grounded structure, such as a battery, PCB, or shield, and the bottom surface of the antenna is in contact with the grounded structure. Therefore, the problem of insufficient space for antenna placement in the electronic device can be solved. In addition, the antenna can be manufactured as an independent modular piece, so that the antenna can be reused. Alternatively, the antenna and the grounding structure of the electronic device, such as the battery, can also be integrated into an integrated structure to facilitate the realization of the thinning design of the electronic device.

Description of the drawings

FIG. 1 is a schematic structural diagram of an electronic device provided by an embodiment of the application;

FIG. 2 is a schematic structural diagram of an antenna provided by an embodiment of the application;

FIG. 3 is a schematic structural diagram of an opening of an antenna provided by an embodiment of the application;

4 is a schematic structural diagram of an antenna provided by another embodiment of this application;

FIG. 5 is a schematic structural diagram of an opening of an antenna provided by another embodiment of the application;

FIG. 6 is a schematic structural diagram of an antenna provided by another embodiment of this application;

FIG. 7 is a schematic structural diagram of an antenna provided by another embodiment of this application;

FIG. 8 is a graph of return loss of an antenna with slots opened at three different positions according to an embodiment of the application; FIG.

FIG. 9 is an initial radiation efficiency diagram of an antenna with slots opened at three different positions according to an embodiment of the application; FIG.

FIG. 10 is a schematic structural diagram of an antenna provided by another embodiment of this application;

FIG. 11 is a schematic structural diagram of an antenna provided by an embodiment of the prior art;

FIG. 12 is an initial radiation efficiency diagram of the patch antenna of the prior art and the antenna of the embodiment of the present application;

FIG. 13 is a schematic structural diagram of an antenna provided by another embodiment of this application;

FIG. 14 is a schematic structural diagram of an antenna provided by another embodiment of this application;

15 is a schematic structural diagram of an antenna provided by another embodiment of this application;

Figure 16 shows the simulation of the N79 antenna and the return loss curve of the N79 sample antenna test;

Figure 17 shows the simulation of the N79 antenna and the initial radiation efficiency graph of the N79 sample antenna test;

Figure 18 shows the simulation of the 0.72mm thick N79 antenna and the initial radiation efficiency diagram of the simulation of the 0.5mmN79 antenna;

19 is a schematic structural diagram of an antenna and battery integrated structure provided by an embodiment of the application;

Fig. 20 is an enlarged view of the partial structure at A in Fig. 19.

Reference signs:

1-Electronic equipment; 101-edge area; 102-antenna; 103-battery; 2-opening; 3-top surface; 301-slot;

302-first area; 303-second area; 304-grounding point; 4-bottom surface; 5-feeding line; 501-feeding point;

6-dielectric; 601-first dielectric layer; 602-second dielectric layer; 7-first via; 8-second via;

9-flexible circuit board; 901-feeder connection line.

Detailed ways

In order to facilitate the understanding of the antenna provided by the embodiment of the present application, the specific application scenarios of the antenna are first described below. The antenna of the embodiment of the present application can be applied to a variety of electronic devices. Illustratively, the electronic device may be, but not limited to, a mobile phone, a tablet computer, a smart wearable device, or a personal digital assistant (PDA), etc. The above-mentioned electronic devices all need to transmit signals through an antenna. Taking the electronic device as a mobile phone as an example, referring to Fig. 1, the antenna is usually set in the edge area 101 of the electronic device to improve the radiation efficiency of the antenna.

In order to comply with the development requirements of the communication of the electronic device 1, more and more antennas need to be provided in the electronic device 1. Due to the limited space in the edge area 101 of the electronic device 1 that can be used to set the antenna, this will inevitably bring great challenges to the number of antennas, the design size and the layout of the antenna. In addition, as the number of antennas provided in the electronic device 1 increases, the distance between the radiator of the clearance antenna and the metal structure of the electronic device 1 becomes smaller and smaller, which will greatly reduce the radiation performance of the antenna. In order to solve the above-mentioned problem, the embodiment of the present application provides an antenna, which can be arranged in the middle area inside the electronic device 1, for example, arranged in a battery, a shielding cover, or a printed circuit board (printed circuit board, PCB), etc. On the structural parts, and has a higher radiation efficiency.

Referring to FIG. 2, the antenna provided by an embodiment of the present application has a flat structure with openings 2 at both ends, which may be, but is not limited to, a metal waveguide structure. In addition, the shape of the opening 2 of the flat structure antenna can be, but is not limited to, a quadrilateral or polygonal shape, such as a regular shape such as a rectangle, a parallelogram, a regular hexagon, etc., or any irregular shape. In addition, the shapes of the openings 2 at both ends of the antenna may be the same or different. For ease of description, in the following implementation of the present application, the structure of the antenna is introduced by taking the shape of the openings 2 at both ends of the antenna as a rectangle as an example.

Continuing to refer to FIG. 2, the antenna of this embodiment of the present application has a top surface 3 and a bottom surface 4 disposed opposite to the top surface 3. When the antenna is installed in the electronic device 1 as shown in FIG. 1, the bottom surface 4 of the antenna can be in contact with the ground structure (not shown in the figure) of the electronic device 1. A slot 301 is provided on the top surface 3, and the extending direction of the slot 301 is consistent with the direction of the antenna opening 2 to divide the top surface 3 into a first area 302 and a second area 303 that are not connected to each other, so that the antenna The gap 301 is in an open state. In addition, a grounding point 304 for feeding is provided on the top surface 3 of the antenna, and a feeder 5 is also provided inside the pipe of the antenna. The grounding point 304 can be set in the first area 302 or the second area of the top surface 3. 303.

Referring to Fig. 3, when the feeder line 5 is specifically set up, the feeder line 5 is provided on the middle layer between the top surface 3 and the bottom surface 4 of the antenna, and the feeder line 5 may be a metal microstrip line. Continuing to refer to FIG. 3, the two ends of the feeder line 5 are separately arranged on both sides of the gap 301 on the top surface 3. Among them, one end of the feeder line 5 is provided with a feeding point 501, and the feeding point 501 and the grounding point 304 form a feeding port , Used to realize the feeding of the antenna; the other end of the feeding line 5 is free to extend, so that the feeding of the antenna is in an open circuit state, so as to realize the coupling feeding of the antenna.

Referring to FIG. 3, it can be seen that by opening a slot 301 on the top surface 3 of the antenna, a closed loop current of the same direction can be formed on both sides of the slot 301 along the surface of the antenna.

In addition, referring to Figure 2, on the surface of the antenna, the dominant mode of the field is TE ₁₀ , that is, in the -Y direction (the direction opposite to the Y direction in Figure 2) there is only a magnetic field H _y , which can be simply expressed as: H _y = H ₀ |cos(πx/a)|e-jky, where H ₀ is the amplitude of the field, a is the width of the antenna (the distance between the two side walls), and j=n×H _y .

Obviously, on the two side walls of the antenna (that is, at x=0 and x=a), the current is the largest; from one side of the antenna (at x=0 or x=a) to the opposite side (x= a or x=0), the current on the top surface 3 changes from maximum to minimum. To the opening of the center point, that is, when x=a/2, the current is zero. If the antenna is not slotted, the current will be reversed after crossing the middle point of the antenna, which will make the radiated energy cancel each other in the air, and the radiation efficiency of the antenna will decrease. With the antenna of the present application, by opening a slot 301 on the top surface 3, the current is forced to flow in the same direction, and the radiation efficiency of the antenna is relatively high.

From the current analysis of the resonance point, the width a of the antenna is half a wavelength (λ/2). On the metal surface of the antenna, the antenna forms two λ/2 loop currents (the loop represented by the solid line and the dashed line in Figure 3). The loop current generates the inductance L required for resonance, and the gap 301 on the top surface 3 forms a capacitor C, and the resonant frequency of the antenna can be used

To estimate.

A resonant capacitance C is generated due to the slot 301 on the top surface 3 of the antenna. Therefore, a capacitive device or an inductance device can be connected across both ends of the slot 301 to tune the capacitance generated at the slot 301 of the antenna, so that the resonant frequency of the antenna changes. For example, a capacitive device is connected across the gap 301. At this time, the inherent capacitance of the gap 301 and the capacitance of the capacitive device are connected in parallel, so that the total capacitance is increased, thereby lowering the resonance frequency. In addition, when an inductance device with a small inductance is connected across the gap 301, the total capacitance will decrease, and the resonance frequency will rise at this time. At this time the antenna can become an adjustable antenna.

In addition, referring to FIG. 3, the feeder 5 has a certain distance from the top surface 3 and the bottom surface 4 of the antenna. The distance between the feeder line 5 and the top surface 3 of the antenna and the distance between the feeder line 5 and the bottom surface 4 of the antenna may be equal or different. The feed line 5 can be parallel to the top surface 3 of the antenna, or can be set at a set angle. In a possible embodiment of the present application, the feed line 5 may be arranged orthogonally to the slot 301 on the top surface 3 of the antenna. This can effectively excite the loop current parallel to the port, which is beneficial to enhance the efficiency bandwidth of the antenna.

In this application, the shape of the slot 301 on the top surface 3 of the antenna is not specifically limited. Illustratively, the slot 301 may be, but not limited to, a straight line or a wave shape. In addition, referring to FIG. 3, the size L1 of the slot 301 extending from the first area 302 to the second area 303 can be less than or equal to 1 mm, which can avoid increasing the size of the antenna and help improve the radiation efficiency of the antenna.

2, in the embodiment of the present application, the extending direction of the slot 301 is consistent with the direction of the opening 2 of the antenna, and it can be arranged in the middle of the top surface 3 of the antenna to divide the antenna into two equal areas. Thus, a resonant wave with a resonant frequency can be formed in the rectangular pipe of the antenna. In addition, referring to FIG. 4, the slot 301 can also divide the top surface 3 of the antenna into two unequal regions (hereinafter referred to as the slot 301 offset). In some embodiments of the present application, referring to FIG. 6 and FIG. 7, the slot 301 may also be opened along the diagonal of the top surface 3 of the antenna.

Figure 8 shows the return loss curves of the antenna with the slot 301 opened at three different positions, where the dotted line represents the antenna with the slot 301 opened in the middle of the top surface 3, and the dotted line represents the slot 301 opened on the top surface. For the antenna at the diagonal of 3, the antenna with the slot 301 offset is represented by a solid line. Through analysis, it can be seen that the resonant frequency of the antenna with the slot 301 in the middle of the top surface 3 is 4718 MHz (the frequency corresponding to the mark 4).

Compared with the resonant frequency of the antenna with the slot 301 in the middle of the top surface 3 at 4718MHz, the resonant frequency of the antenna with the slot 301 at the diagonal has dropped to 3336MHz (the frequency corresponding to the mark 3), and the drop is 1382MHz. This is because the length of the slit 301 opened at the opposite corner of the top surface 3 is approximately 1.4 times the length of the slit 301 opened at the middle position of the top surface 3 (

For convenience of explanation, the top surface 3 is assumed to be a square); and because the slot 301 will generate a capacitance C required for antenna resonance. As the slot 301 lengthens, the capacitance C increases. When a slot 301 is opened in the middle of the top surface 3, referring to FIG. 3, two loop currents are formed at the cross section of the opening 2 of the antenna, and the two are equal in size. When the slot 301 is opened at the diagonal position of the top surface 3, referring to FIG. 6, only a current loop is formed at the cross section of the opening 2 of the antenna, and the length of the current loop increases, so that the inductance L generated by it also increases. The increase. The resonant frequency of the antenna is determined by the formula,

Decided. When the capacitance and inductance are both greatly increased, the resonant frequency of the antenna will be greatly reduced. Therefore, the resonant frequency of the antenna with the slot 301 at the diagonal will drop from 4718MHz to 3336MHz.

In addition, when the slot 301 is biased, referring to Figure 5, the antenna will produce two resonances, the first resonance is at 4102MHz (the frequency corresponding to mark 1), and the second resonance is at 6227MHz (the frequency corresponding to mark 2) . Compared with the antenna with a slot 301 in the middle of the top surface 3, it becomes a dual-resonant antenna. Among them, a large loop current and a small loop current are generated at the cross section of the opening 2 of the antenna. It can be understood that at low frequency resonance, a large ring current has a strong current distribution, while a small ring current has a weak current. Therefore, we believe that the inductance L generated by the large loop current and the capacitance C generated by the slot 301 determine the low-frequency resonance frequency of the antenna. Compared with the antenna with a slot 301 in the middle of the top surface 3, the length of the slot 301 of the antenna biased by the slot 301 has not changed, and the capacitance C has not changed. However, the length of the large loop current is greater than the length of the loop current in FIG. 3, therefore, the inductance L generated by the large loop current of the antenna biased by the slot 301 increases. Therefore, the first resonance of the antenna biased by the slot 301 moves toward a low frequency. In the same way, a small ring current determines the high-frequency resonance frequency, which will move the resonance point to high-frequency. It can be seen from the above that the change of the two resonant frequency points can be tuned by adjusting the offset position of the slot 301 on the top surface 3, so that the antenna can have dual-frequency characteristics and become a dual-frequency antenna.

With reference to FIG. 9, FIG. 9 is the initial radiation efficiency curve of the antenna with the above-mentioned slot 301 opened at three different positions. Among them, the efficiency of the antenna with the slot 301 opened in the middle of the top surface 3 is represented by a solid line. It can be observed that its efficiency bandwidth is better. Mark 4 indicates that the efficiency reaches its peak at its resonance frequency, but at mark 5, an efficiency pit appears. It corresponds to the resonance point corresponding to mark 5 in Figure 8, f=5236MHz. This resonance is _{excited by the TE 10} mode of the antenna (that is, the mode that can be excited by the antenna without the slot 301, which only exists when the center is slotted). In this case, it forms a reverse on the top surface 3 of the antenna. Toward current, so that part of the radiated energy in the space offsets each other, causing this efficiency pit. However, this efficiency loss is not very large, and it drops by about 0.7dB in this embodiment. But because this efficiency point is close to the main resonance point (4718MHz), the efficiency bandwidth after matching can be expanded. This is conducive to the realization of N79 (band 4400-5000MHz) when the antenna has a small thickness (in this embodiment, the thickness of the antenna refers to the maximum distance between the top surface 3 and the bottom surface 4), such as 0.5mm or less. And the design of WIFI5G antenna.

In FIG. 9, the efficiency of the antenna in which the slot 301 is opened at the diagonal corner of the top surface 3 is represented by a dash-dotted line. Mark 3 is the resonant frequency point of the antenna, f=3336MHz. At this time, the efficiency reaches the peak. Compared with the resonant frequency of the antenna with the slot 301 in the middle of the top surface 3 at 4718MHz, the resonant frequency of the antenna with the slot 301 in the diagonal corner of the top surface 3 drops to 1382MHz, which has a 29% frequency drop. Since the slot 301 is opened at the diagonal corner of the top surface 3, the efficiency bandwidth of the antenna will be greatly reduced. Therefore, the antenna solution with the slot 301 opened at the diagonal corner of the top surface 3 is more suitable for narrowband antennas, such as WIFI 2.4G and Some long-term evolution (LTE) MIMO antennas.

In addition, since the width of the antenna and the resonant frequency of the antenna are in a linear relationship, when the same resonance efficiency is satisfied, compared to the antenna in which the slot 301 is opened at the diagonal of the top surface 3, the slot 301 is opened at the top. The overall size of the antenna at the diagonal corner of the face 3 can be reduced by about 1/3, which is beneficial to the reduction of the antenna size.

Continuing to refer to FIG. 9, the efficiency of the antenna biased by the slot 301 is represented by a dotted line. Wherein, mark 1 and mark 2 are the two resonant frequency points of the antenna, which respectively reach the peak efficiency. At this time, the two resonant frequencies of the antenna can be tuned by adjusting the distance from the center of the slot 301. This is a simple and effective way to design dual-band antennas.

In addition, referring to FIG. 10, the pipe of the antenna of the embodiment of the present application can also be filled with a medium 6. The medium 6 can include a multilayer structure stacked, so that the feeder 5 can be placed between two adjacent layers of the medium 6. between. The material of the medium 6 can be, but is not limited to, polytetrafluoroethylene (PTFE). In order to make the antenna have better bandwidth characteristics, the dielectric constant of the filling material generally does not exceed 3. At the same time, the smaller the dielectric loss of the filling material, the better.

Various attempts have been made by those skilled in the art in order to be able to use a battery, a shield cover, or a grounding structure such as a PCB in the middle area of the electronic device 1 to arrange the antenna. Referring to FIG. 11, FIG. 11 shows a design scheme of an existing patch antenna. However, due to the narrow bandwidth of the patch antenna, in order to increase the bandwidth of the patch antenna, the thickness of the antenna needs to be increased. For 5G NR antennas, it requires a relatively wide frequency band. For example, the N77 frequency band needs to cover 3300MHz-4200MHz, which is an absolute bandwidth of 900MHz. To meet this requirement, the thickness of the patch antenna needs to be increased to 1.5mm. This thickness is not very high in some electronic devices, but it is difficult to meet the ultra-thin design requirements of mobile phones and other electronic devices.

12, FIG. 12 is the initial radiation efficiency curve of the above-mentioned patch antenna and the antenna of the embodiment of the present application (the slot 301 is opened in the middle position of the top surface 3). The radiation efficiency of the patch antenna described above is represented by a solid line, and the radiation efficiency of the antenna of the embodiment of the present application is represented by a dashed line. Among them, when the area of the top surface 3 of the patch antenna shown in Figure 11 is 25mm×22mm, it needs a thickness of 1.5mm (the distance between the top surface 3 and the bottom surface 4 in Figure 3) to cover a frequency band near N77 (3216MHz-4121MHz), the frequency band between Mark 1 and Mark 2, with a bandwidth of 905MHz. In order to achieve the same bandwidth, using the antenna of the embodiment of the present application, under the condition that the area of the top surface 3 is the same, its thickness can be reduced to 0.8 mm. By analyzing and comparing the curves in FIG. 12, it can be known that compared with the patch antenna shown in FIG. 11, the thickness reduction rate of the antenna using the embodiment of the present application is 0.8mm/1.5mm=0.53=53%, which can be Used in electronic equipment with ultra-thin design requirements.

Referring to FIG. 13, in an embodiment of the present application, an N79 (frequency band of 4400-5000 MHz) antenna is taken as an example to introduce the design and processing of the antenna of the embodiment of the present application. In this embodiment, the PCB processing technology is used to complete the sample production of the antenna. Among them, in order to obtain better bandwidth characteristics of the antenna, the dielectric constant of the medium 6 filled in the antenna should be low, and the material loss should also be small. . Therefore, the base material of the medium 6 can be selected as PTFE, and its dielectric constant and loss are respectively: Er=2.2, tanδ=0.0009. In addition, referring to FIG. 13, in this embodiment, the extension length of the sample of the N79 antenna (the distance between the two openings 2) is set to L, the thickness of the antenna is set to H, and the width of the antenna (between the two sides If the distance between) is set to D, the dimension of the N79 antenna is L×D×H=17mm×19mm×0.72mm.

Referring to FIG. 13, in this embodiment, the filling medium 6 of the antenna can be configured as a two-layer structure, the top surface of the second dielectric layer 602 is provided with a copper layer, and a gap 301 is opened in the middle of the copper layer. The width of is, for example, 0.5 mm. In order to form the two opposite side walls of the antenna for connecting the top surface 3 and the bottom surface 4, it is difficult to process a complete side wall on the above-mentioned layer structure. The formed layer structure is provided with two rows of first via holes 7, and the plurality of first via holes 7 are closely arranged as sidewalls, wherein the first via holes 7 penetrate the entire layer structure along the stacking direction of the layer structure. In order to clearly show the feeding structure, the medium 6 is hidden in FIG. 14. In this embodiment, the aperture of the first via 7 is not specifically limited, for example, it can be 0.25 mm; in order to reduce the impact on the radiation efficiency of the antenna, the distance between two adjacent first vias 7 should be designed Is smaller, for example, not more than 0.25mm. In addition, referring to FIG. 15, the feeder 5 of the antenna can be arranged between the two layers of dielectrics 6. In this way, the second via 8 can be opened on the first layer of the dielectric 6 so that the ground point 304 of the antenna can pass through the second via. 8 is connected to the feeder 5 for power feeding.

Refer to Figure 16, which shows the simulation of the N79 antenna and the test return loss curve of the N79 sample antenna. Due to the error caused by factors such as machining accuracy, the simulated resonance point of the N79 antenna is 4641MHz, which is 49MHz lower than the 4690MHz obtained by the actual test of the N79 sample antenna. Compared with the 4400MHz resonance frequency of the N79 antenna, there is only a 1% deviation. Therefore, in this application, the simulation of the N79 antenna is relatively reliable.

In addition, Fig. 17 is the simulation of the radiation efficiency of the N79 antenna and the comparison of the radiation efficiency of the above-mentioned N79 sample antenna. The simulation result of the radiation efficiency of the N79 antenna is represented by a curve with a solid circle, and the radiation of the N79 sample antenna The result of efficiency is represented by a curve with a hollow circle. In the N79 operating frequency band of 4400-5000MHz, during simulation, 3 matching components (capacitors, resistors or inductors) are used at the feed port of the antenna, and a relatively flat and wide efficiency bandwidth is obtained. The lowest radiation efficiency of the band edge is -4.4dB, and the average efficiency is -3.7dB.

When testing the radiation efficiency of the aforementioned N79 sample antenna, only two matching parts were used at the antenna feed port. It can be seen from Figure 17 that compared with the simulation, the N79 sample antenna has a very high peak efficiency, which is -1.3dB, and the average efficiency is also relatively high at -3.0dB, which is higher than the average efficiency of the above simulation. Out about 0.7dB. Although the lowest radiation efficiency of the band edge is -5.1 dB, which is about 0.7 dB lower than the simulated lowest radiation efficiency of the band edge, this is also sufficient to show that the performance of the antenna fabricated by the embodiment of the present application is relatively good. In addition, the test results can also confirm that the simulation is reliable.

In order to meet the ultra-thin design of electronic devices, we hope that the thickness of the antenna is as small as possible. Because, through the above-mentioned simulation and the actual measurement and comparison of the 0.72mm-thick N79 sample antenna, the reliability of the simulation can be proved, and we can use the simulation to predict the performance of the 0.5mm-thick antenna. Among them, the base material of the antenna still uses PTFE, and its dielectric constant and loss are respectively: Er=2.2, tanδ=0.0009. For the structure of the antenna, refer to FIG. 13, and the slot 301 on the top surface 3 is also set to be 0.5 mm wide. Due to the decrease in the thickness of the antenna, in order to make the antenna have a higher radiation efficiency, the width D of the antenna can be increased by 1 mm, so that the size of the antenna is L×D×H=17mm×20mm×0.5mm.

Figure 18 shows the simulation results of the radiation efficiency of the N79 antenna with thicknesses of 0.72mm and 0.5mm respectively. The simulation of the radiation efficiency of the 0.72mm thick N79 antenna is represented by a solid line, and the radiation of the 0.5mm thick N79 antenna The simulation of efficiency is represented by a dot-dash line. As the thickness decreases from 0.72mm to 0.5mm, the bandwidth of the antenna becomes significantly narrower. However, the simulation of the N79 antenna with a thickness of 0.5mm shows an average radiation efficiency of -4.2dB in its frequency band. Since the simulated average radiation efficiency of the 0.72mm thick N79 antenna is -3.7dB, the simulated average radiation efficiency of the 0.5mm thick N79 antenna is reduced by 0.5dB, but it can still meet the radiation efficiency of the antenna. Claim.

Through the above simulation of the N79 sample antenna with a thickness of 0.72 mm, the N79 antenna with a thickness of 0.72 mm, and the simulation of the radiation efficiency of the N79 antenna with a thickness of 0.5 mm, it can be known that the antenna obtained by adopting the design scheme of the embodiment of the present application, It can not only make the thickness of the antenna less than 1mm, or even less than 0.5mm, but also meet the requirements of the antenna's radiation performance. Further, the ratio of the height H and the width D of the section of the opening 2 of the antenna can be satisfied: H/D<0.025, so that the height and width of the antenna can be adjusted to meet the bandwidth requirements and have higher radiation efficiency. .

In addition to the above-mentioned solution of using PCB processing technology to complete the production of the antenna, referring to FIG. 19, the antenna of the embodiment of the present application can also be integrated with the battery 102 of the electronic device. As shown in FIG. 20, the antenna in this embodiment can also be formed by stacking two layers of dielectric 6, wherein the first dielectric layer 601 is arranged on the body of the battery 102, and the feeder is arranged on the first dielectric layer 601 and the first dielectric layer 601. Between two dielectric layers 602. The end surface of the second dielectric layer 602 away from the first dielectric layer 601 is coated with a copper layer. The copper layer can be divided according to the number, size, and position of the antenna to be installed. For example, refer to FIG. 19, when When six antennas are to be formed on the battery, the above copper layer can be divided into six pieces as the top surface 3 of each antenna, for example, two WIFI2.4 antennas, two WIFI5G and two N78 antennas are formed. When specifically setting the slot 301 of the antenna, the slot 301 can be set at the middle position, diagonal, or offset of the top surface 3 according to the frequency band requirements of the antenna.

In addition, in order to realize the feeding of the antenna, when the feeding port of the antenna is specifically set, the grounding point 304 of the top surface 3 can be connected to the feeding point of the feeder line by perforating. Alternatively, referring to FIG. 20, a flexible printed circuit (FPC) 9 (flexible printed circuit) is provided on one side of the above-mentioned integrated component, and a feeder connection line 901 is drawn from the flexible circuit board 9 to connect the feeder The line 901 is feed-connected to the ground point of the antenna.

Since the thickness of the antenna of the embodiment of the present application can be designed to be small, by integrating the antenna and the battery 103 into an integrated structure, the surface of the battery 103 can be used to design the antenna while avoiding the overall thickness of the integrated component. It can meet the requirements of thinning design of electronic equipment.

The above are only specific implementations of this application, but the scope of protection of this application is not limited to this. Any person skilled in the art can easily conceive of changes or substitutions within the technical scope disclosed in this application, which shall cover Within the scope of protection of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

Claims

An antenna, characterized in that the antenna is a flat pipe-type structure with openings at both ends, and the antenna includes a feeder line, wherein:

The antenna has a top surface, the top surface is provided with a slot, the antenna is in an open state at the slot, and the top surface is also provided with a grounding point;

The feeder line is arranged inside the pipe of the antenna, two ends of the feeder line are separately arranged on both sides of the slot, one end of the feeder line has a feeding point, and the feeding point is connected to the connection The location forms a feed port, and the other end of the feed line extends freely.
The antenna according to claim 1, wherein the antenna further comprises a bottom surface disposed opposite to the top surface, the feed line and the top surface are spaced apart, and the feed line and the top surface are spaced apart from each other. There are intervals between the bottom surfaces.
The antenna of claim 1 or 2, wherein the slot divides the top surface into a first area and a second area; at the slot, the first area and the second area A capacitive device or an inductance device is arranged between.
The antenna according to any one of claims 1 to 3, wherein the size of the slot along the direction from the first area to the second area is not greater than 1 mm.
The antenna according to any one of claims 2 to 4, wherein the distance between the top surface and the bottom surface is less than or equal to 1 mm.
The antenna according to any one of claims 2 to 5, wherein the antenna further comprises two side surfaces for connecting the top surface and the bottom surface, the resonant wavelength of the antenna is λ, and the The distance between the two sides is less than or equal to λ/2.
The antenna according to any one of claims 2 to 6, wherein the antenna further comprises two side surfaces for connecting the top surface and the bottom surface, and a gap between the top surface and the bottom surface The distance H and the distance D between the two side surfaces satisfy: H/D≤0.025.
The antenna according to any one of claims 1 to 7, wherein the extending direction of the slot is consistent with the opening direction of the antenna, and the area of the first area and the second area are equal; or, The areas of the first area and the second area are not equal.
7. The antenna according to any one of claims 1 to 7, wherein the slot is arranged along the diagonal of the top surface.
The antenna according to any one of claims 1-9, wherein the antenna is further filled with a medium, and the dielectric constant of the medium is less than or equal to 3.
The antenna according to any one of claims 1 to 10, wherein the antenna is filled with stacked multilayer dielectrics, and the feeder line is arranged between two adjacent layers of the dielectric.
The antenna of claim 11, wherein the antenna further comprises a bottom surface disposed opposite to the top surface, the multilayer dielectric is disposed between the top surface and the bottom surface of the antenna, and the top surface Contact with the bottom surface through two rows of via holes penetrating the multilayer dielectric;

The arrangement direction of the via holes in each row is consistent with the opening direction of the antenna, and the two rows of via holes and the top surface and the bottom surface enclose a pipe of the antenna.
The antenna according to claim 12, wherein in each column of the via holes, a gap between two adjacent via holes is less than or equal to 0.3 mm.
An electronic device, characterized by comprising the antenna according to any one of claims 1-13.
The electronic device according to claim 14, further comprising a grounding structure, the antenna is disposed on the grounding structure, and the antenna includes a bottom surface disposed opposite to the top surface, and the bottom surface is connected to the ground structure. The grounding structure is in contact.
15. The electronic device according to claim 15, wherein the antenna and the ground structure are integrated into an integrated structure.