Antenna structure and electronic equipment

Abstract

An antenna structure and an electronic device relate to the technical field of antennas and the technical field of terminals. The antenna structure comprises a radiator, a first branch knot and a second branch knot, the radiator comprises a groove ring structure, a first side wall of the groove ring structure is provided with a gap, and the gap divides the first side wall into a first part and a second part; the first branch knot is located between the first side wall and a second side wall of the groove ring structure, the first branch knot is used for coupling a feeding point, the second side wall is located on the opposite side of the first side wall, and the feeding point is located on the first part or the second side wall; the second branch knot is connected with the first part, and a part of the second branch knot is opposite to the second part. The antenna structure is easy to realize short configuration design, and can be applied to small-clearance even zero-clearance electronic equipment.

Description

Technical Field

[0001] The present application relates to the field of antenna technology, and in particular to an antenna structure and an electronic device. Background Art

[0002] With the development of modern wireless communication technology, antennas play an increasingly important role as front-end devices of wireless communication systems. At present, electronic devices generally have antennas on their metal frames, but as the number of antennas on electronic devices increases, electronic devices face the problem of not having a long enough metal frame to carry the newly added antennas.

[0003] Furthermore, electronic devices such as mobile phones, tablet computers or smart watches have an increasing number of metal parts inside, so the clearance left for the antenna is decreasing, and the lack of clearance will lead to a decrease in the radiation efficiency of the antenna. The clearance refers to the open area within the vertical projection area of ​​the antenna.

[0004] In summary, there is an urgent need for an antenna structure with a short configuration and low clearance requirements. Utility Model Content

[0005] In order to solve the above problems, the present application provides an antenna structure and an electronic device. The antenna structure is easy to implement a short configuration design and can be applied to electronic devices with small clearance or even zero clearance.

[0006] In a first aspect, the present application provides an antenna structure, which includes a radiator, a first branch, and a second branch. The radiator includes a slot ring structure, and a first side wall of the slot ring structure is provided with a gap, and the gap separates the first side wall into a first part and a second part. The first branch is located between the first side wall and the second side wall of the slot ring structure, the first branch is used to couple the feeding point, the second side wall is located on the opposite side of the first side wall, and the feeding point is located in the first part or the second side wall. The second branch is connected to the first part, and part of the second branch is opposite to the second part.

[0007] The solution provided by the present application is that the first branch of the antenna structure is used for feeding, and the second branch is opposite to the second part, so the second branch forms a distributed capacitance with the second side wall. After feeding, the radiator part in the slot ring and the surrounding part excites a closed loop current of the same phase, thereby generating the inductance required for the antenna resonance. The inductance and the distributed capacitance together form a resonant structure. Among them, the inductance can be adjusted by adjusting the slot area of ​​the slot ring structure, and the capacitance can be regulated by adjusting the area relative to the second branch and the second part, the distance between the second branch and the second part, or changing the dielectric type between the second branch and the second part. Therefore, the solution of the present application can configure the capacitance and inductance values ​​more easily without changing the length of the antenna, can achieve larger capacitance and inductance values ​​without increasing the lumped circuit, is easy to implement a short configuration design, and avoids the problems of unstable resonance and narrow bandwidth caused by increasing the lumped circuit.

[0008] The resonance of traditional low-frequency antennas, such as inverted-F antenna (IFA) and left-hand antenna, is related to the one-dimensional length of the antenna, resulting in that traditional low-frequency antennas are generally long. The antenna structure provided in the present application is easy to configure a larger capacitance value, or a larger inductance value is configured by adjusting the cross-sectional area of ​​the slot ring structure, so that the resonant frequency of the antenna structure is reduced, so it can be used as a low-frequency (Low Band, LB) antenna and the length is reduced.

[0009] Furthermore, when the radiator of the wire structure directly uses the metal frame or metal floor of the electronic device, no clearance is required in the direction parallel to the plane where the metal floor is located. When the radiator of the wire structure is stacked with the metal floor of the electronic device, no clearance is required in the direction perpendicular to the plane where the metal floor is located. Therefore, the above antenna structure reduces the clearance requirement.

[0010] In a possible implementation manner, the slot ring structure is filled with a dielectric material.

[0011] In a possible implementation, the slot ring structure includes a first region and a second region, the first region is filled with a dielectric material, the second region is filled with a magnetoelectric material, and the first region includes a region between the second branch and the first sidewall.

[0012] By filling magnetoelectric materials, the radiation efficiency of the antenna can be improved, the bandwidth can be increased and the size of the antenna can be reduced.

[0013] In a possible implementation, the second branch includes one or more folding portions, and the folding portions are used to change the extension direction of the second branch.

[0014] By bending the second branch, the second branch can form a plurality of distributed capacitors connected in parallel with the second portion of the first side wall, thereby increasing the total capacitance, shortening the length of the second branch, and further shortening the length of the antenna structure, thus facilitating the realization of a short configuration design of the antenna structure.

[0015] In a possible implementation, the antenna structure further includes a third branch. The third branch is connected to the first portion, and part of the third branch is opposite to the second portion. By forming a plurality of distributed capacitors connected in parallel, the capacitance is increased, and the length of the second branch and the third branch is shortened, thereby shortening the length of the antenna structure, and thus facilitating the realization of a short configuration design of the antenna structure.

[0016] In one possible implementation, the second branch includes a second fixed portion and a second extending portion, the third branch includes a third fixed portion and a third extending portion, the second fixed portion and the third fixed portion are parallel, the second extending portion and the third extending portion are parallel, the second fixed portion is connected to the first portion, and the third fixed portion is connected to the first portion.

[0017] In a possible implementation manner, the second branch is located in the groove ring structure, and the second branch extends to a region between the second portion and the second side wall.

[0018] In a possible implementation manner, the second branch is located outside the groove ring structure.

[0019] In a possible implementation, the second branch includes a second fixing portion and a second extending portion, the second fixing portion is connected to the first portion, and the second extending portion includes a plurality of mutually separated adjusting portions, and two adjacent adjusting portions are connected via a PIN diode.

[0020] In a possible implementation, the feeding point is located on the second side wall, the first end of the first branch is connected to the feeding point, and the second end of the first branch extends to the area between the first part and the second side wall.

[0021] In a possible implementation, the feeding point is located on the second side wall, the first end of the first branch is connected to the feeding point, and the second end of the first branch is connected to the first part.

[0022] In a possible implementation, the feeding point is located on the second side wall, the first end of the first branch is connected to the feeding point, and the second end of the first branch is connected to the second part.

[0023] In a possible implementation, the feeding point is located in the first part, the first end of the first branch is connected to the feeding point, and the second end of the first branch is connected to the second part.

[0024] In a second aspect, the present application further provides an electronic device, which may be a mobile phone, a tablet computer, a laptop computer, a wearable device (such as a smart watch), a router, etc. The electronic device includes one or more antenna structures provided in the first aspect.

[0025] In a possible implementation, the radiator is a metal floor of the electronic device or a metal frame of the electronic device. In this case, the antenna structure may not require clearance in the X and Y directions of the electronic device. The plane defined by the X and Y directions is parallel to the plane where the metal floor of the electronic device is located.

[0026] In a possible implementation, the radiator is stacked with the metal floor of the electronic device, and the first side wall and the second side wall of the antenna structure are parallel to the metal floor. In this case, the antenna structure does not need clearance in the Z direction of the electronic device. The Z direction is perpendicular to the plane where the metal floor of the electronic device is located. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Scenario diagram provided for the embodiment of this application Figure 1 ;

[0028] Figure 2 A schematic diagram of an antenna structure provided in an embodiment of the present application;

[0029] Figure 3 Schematic diagram of the principle provided by the embodiment of this application Figure 1 ;

[0030] Figure 4A Schematic diagram of the metal floor provided in the embodiment of the present application Figure 1 ;

[0031] Figure 4B A schematic diagram of another antenna structure provided in an embodiment of the present application;

[0032] Figure 5 The simulation results provided in this application example are shown in FIG. Figure 1 ;

[0033] Figure 6 A schematic diagram of another antenna structure provided in an embodiment of the present application;

[0034] Fig. 7A Schematic diagram of the metal floor provided in the embodiment of the present application Figure 2 ;

[0035] Figure 7B A schematic diagram of another antenna structure provided in an embodiment of the present application;

[0036] Figure 8 The simulation results provided in this application example are shown in FIG. Figure 2 ;

[0037] Fig. 9 The simulation results provided in this embodiment are shown in FIG. Figure 3 ;

[0038] Fig.10 Schematic diagram 4 of simulation results provided for an embodiment of the present application;

[0039] Fig.11 The simulation results provided in this embodiment are shown in FIG. Figure 5 ;

[0040] Fig.12 The simulation results provided in this embodiment are shown in FIG. Figure 6 ;

[0041] Fig.13 Schematic diagram of the principle provided by the embodiment of this application Figure 2 ;

[0042] Fig.14 A schematic diagram of another antenna structure provided in an embodiment of the present application;

[0043] Fig.15 Schematic diagram 7 of simulation results provided for the embodiment of the present application;

[0044] Fig.16 A schematic diagram of another antenna structure provided in an embodiment of the present application;

[0045] Fig.17 Schematic diagram of the principle provided by the embodiment of this application Figure 3 ;

[0046] Fig.18 The simulation results provided in this embodiment are shown in FIG. Figure 8 ;

[0047] Fig.19 A Smith chart of the antenna structure provided in the embodiment of the present application;

[0048] Fig. 20 A schematic diagram of another antenna structure provided in an embodiment of the present application;

[0049] Fig.21 A schematic diagram of another antenna structure provided in an embodiment of the present application;

[0050] Fig. 22 A schematic diagram of another antenna structure provided in an embodiment of the present application;

[0051] Fig.23 A schematic diagram of another antenna structure provided in an embodiment of the present application;

[0052] Fig.24A schematic diagram of direct feeding of an antenna structure provided in an embodiment of the present application. DETAILED DESCRIPTION

[0053] It should be understood that the direction names such as “up”, “down”, “left” and “right” in the following embodiments of the present application are for illustrative purposes only and require reference to the directions in the accompanying drawings and do not constitute a limitation on the technical solution of the present application.

[0054] The terms "first", "second", etc. in the description of this application are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features.

[0055] In the present application, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium.

[0056] In order to enable persons skilled in the art to more clearly understand the solution of the present application, the application scenario of the technical solution of the present application is first described below.

[0057] See also Figure 1 , which is a schematic diagram of a scenario provided by an embodiment of the present application Figure 1 .

[0058] The slot loop antenna is an inductive coupling element (ICE) antenna. Figure 1 As shown, metal in a strip area is removed from a metal plate 10 to form a clear area 11, and a gap 12 is opened on the side, and a feed source is set at the gap 12 to form an ICE antenna. A circulating current 14 with the same phase will be excited on and near the ICE antenna. The current in other areas on the metal floor is a straight line 15 from top to bottom. The radiation of the ICE antenna is mainly contributed by these DC beams.

[0059] For low-frequency (Low Band, LB) ICE antennas, about 80% of the energy is radiated through the floor. The antenna unit is only an excitation unit and cannot effectively generate radiation. The ICE antenna is a ring-shaped excitation source. A typical example is the left-handed antenna. When its length is less than 1 / 4 wavelength, the impedance of the input port is inductive, so it is called an inductively coupled excitation source. However, for the antenna to resonate, the antenna structure must be able to generate capacitance and inductance at the same time. Although the ICE antenna is excited at the slot, resulting in a circulating current on the antenna that can provide sufficient inductance, the size of the slot 12 is too small to generate sufficient capacitance. Even if it can resonate, the frequency will be high and cannot be used in the LB band. Therefore, in order to obtain a resonant antenna in the prior art, a lumped capacitor needs to be connected across the slot 12.

[0060] This method of adding a lumped capacitor at the slot can make the ICE antenna resonate. However, when the antenna clearance is relatively poor, the value of the lumped capacitor cannot be too large, and generally will not exceed 1pF, otherwise the resonance of the antenna will become shallower or even non-resonant. In addition, the resonance of the ICE antenna is related to the one-dimensional length of the antenna, resulting in a single antenna requiring a longer metal frame. Current electronic devices have dual connectivity (E-UTRA-NR Dual Connectivity, EN-DC) requirements for 5G and LTE. Due to the increase in the number of low-frequency antennas required, electronic devices do not have a long enough metal frame to carry the newly added ICE antenna.

[0061] In order to solve the above technical problems, the present application provides an antenna structure and an electronic device. The antenna structure is easy to realize miniaturized design and can be applied to electronic devices with small or even zero clearance, which is described in detail below with reference to the accompanying drawings.

[0062] See also Figure 2 , which is a schematic diagram of an antenna structure provided in an embodiment of the present application.

[0063] Figure 2 The antenna structure 20 shown includes a radiator 21 , a first branch 23 and a second branch 24 .

[0064] The radiator 21 is made of metal, and may be a metal floor or a metal frame of an electronic device, or a separately provided metal carrier, which is not specifically limited in the embodiment of the present application.

[0065] The frame of the radiator 21 includes a groove ring structure 22. The groove ring structure 22 is a narrow square and includes four side walls, wherein the first side wall is the outermost side wall, and the second side wall 28 is opposite to the first side wall. A gap 25 is provided on the first side wall.

[0066] The gap 25 divides the first side wall into a first portion 26 and a second portion 27 .

[0067] The first branch 23 is located between the first side wall and the second side wall 28. Figure 2 The first branch 23 is specifically located between the first portion 26 of the first side wall and the second side wall 28. The first branch 23 is used for coupling feeding, and the feeding point is 29. Figure 2 In the example, the feeding point 29 is located on the second side wall 29 . In other possible implementations, the feeding point 29 may also be located on the first part 26 of the first side wall.

[0068] The second branch 24 is connected to the first portion 26 , and a portion of the second branch 24 is opposite to the second portion 27 .

[0069] See also Figure 3, which is a schematic diagram of the principle provided by the embodiment of the present application Figure 1 .

[0070] After the first branch 23 is connected to the feeding point, in-phase closed commutation is stimulated on the slot ring structure and the radiator around the slot ring structure, thereby generating the inductance required for antenna resonance.

[0071] When the second branch 24 is opposite to the second portion 27 , a distributed capacitor is formed.

[0072] The distributed capacitance and inductance together form a resonant structure. The relationship between the resonant frequency f and the inductance and capacitance is as follows:

[0073]

[0074] In the antenna structure of the present application, the inductance L is positively correlated with the slot area of ​​the slot ring structure 22. The slot area of ​​the slot ring structure 22 is the area of ​​the slot ring structure 22. Figure 3 The cross-sectional area of ​​the projection on the XY plane. By adjusting the cross-sectional area of ​​the slot ring structure 22, L can be increased, so that the resonant frequency decreases without increasing the length of the antenna structure. The resonant frequency of traditional IFA antennas and left-handed antennas is only related to the length of the antenna. In order to reduce the resonant frequency, the antenna length needs to be increased. Therefore, the present application solution facilitates the realization of a short configuration design.

[0075] The distributed capacitance C in the antenna structure satisfies the following formula:

[0076]

[0077] Wherein, S is the area of ​​the second branch 24 and the second portion 27 facing each other, ε r is the dielectric constant of the medium in the region between the second branch 24 and the second portion 27 , and d is the distance between the second branch 24 and the second portion 27 .

[0078] In the antenna structure of the present application, it is also convenient to adjust the capacitance C of the distributed capacitance. For example, the area S facing the second branch 24 and the second part 27 can be increased, or the distance d between the second branch 24 and the second part 27 can be reduced, or the dielectric constant ε can be filled in the area between the second branch 24 and the second part 27. r Larger dielectric material. By increasing C, the resonant frequency is reduced without increasing the length of the antenna structure, so the present application solution facilitates the realization of a short configuration design.

[0079] Furthermore, when adjusting the capacitance value of the distributed capacitance, the present application solution can achieve a larger capacitance value, for example, the capacitance value can reach more than 5pF, so a larger capacitance value can be achieved without increasing the lumped circuit, reducing space occupancy, and avoiding the problems of unstable resonance and narrow bandwidth caused by increasing the lumped circuit. In addition, if the radiator of the antenna structure is a metal frame of an electronic device, the present application solution can maintain the gap 25 in a shorter state. This is because the prior art solution needs to generate distributed capacitance by opening a long gap, but the present application solution does not need to construct the distributed capacitance by increasing the size of the gap 25. On the one hand, it is more beautiful, and on the other hand, it will not destroy the stability of the device structure, and avoid the structural strength of the electronic device being damaged by opening the gap too wide.

[0080] Furthermore, when the radiator of the wire structure directly uses the metal frame or metal floor of the electronic device, no clearance is required in the direction parallel to the plane where the metal floor is located. When the radiator of the antenna wire structure is stacked with the metal floor of the electronic device, no clearance is required in the direction perpendicular to the plane where the metal floor is located. Therefore, the above antenna structure reduces the clearance requirement.

[0081] Figure 2 The feeding position of the first branch 23 in the embodiment has a large degree of freedom in selection, and coupled feeding can be achieved by connecting the feeding point through only one solder joint, so fewer solder joints are required for electrical connection, which can reduce hardware costs and enhance reliability.

[0082] The application scenarios and implementation methods of the antenna structure of the present application are explained below in conjunction with specific implementation methods.

[0083] See also Figure 4A and Figure 4B . Figure 4B A schematic diagram of another antenna structure provided in an embodiment of the present application.

[0084] In the embodiment of the present application, the radiator of the antenna structure is taken as the metal floor of the electronic device. The area specifications of the metal floor of the electronic device using the antenna structure are: 80mm wide and 160mm long. The antenna structure is located in the middle of the side of the metal floor. The specific specifications of the antenna structure are as follows:

[0085] Length L0 = 40 mm, width W = 2 mm, height H = 3.0 mm, slot width D = 0.6 mm, dielectric constant ε of the dielectric material of the antenna in the slot ring structure r =3.5, the dielectric loss of the material tanδ=0.001; the second branch is L-shaped, the height of the second branch is equal to the height H of the groove ring structure, and the distance D1 between the second branch and the second part of the first side wall is 0.7mm.

[0086] Among them, dielectric materials, also known as electrical insulating materials, refer to materials that only have a very small current flowing through them under the action of an electric field. Dielectric loss tanδ = active power P / reactive power Q. Tanδ is also called loss tangent, which is the ratio ε1 / ε2, where ε1 and ε2 are the real and imaginary parts of the dielectric constant, respectively.

[0087] By changing the length of the second branch, the size of the distributed capacitance of the antenna structure can be changed, thereby changing the resonant frequency of the antenna structure. For details, see Figure 5 shown.

[0088] See also Figure 5 , which is a schematic diagram of the simulation results provided by the embodiment of the present application Figure 1 .

[0089] S-Parameter (Scattering-Parameter, S-Parameter) is a network parameter based on the relationship between incident wave and reflected wave. S11 can be used to indicate the magnitude of reflected power.

[0090] Figure 5 In the figure, as the length of the second branch gradually increases from 8.6 mm to 19.8 mm, the distributed capacitance of the antenna structure increases, so that the resonant frequency of the antenna structure decreases from 1021 MHz to 698 MHz, and the antenna structure can be used as a LB antenna.

[0091] In a typical division, LB includes a frequency range of 698 MHz to 960 MHz.

[0092] It can be seen that at this time Figure 4B The antenna structure does not require any matching devices and has a simple structure. And because the extension of the second branch leads to an increase in the distributed capacitance, which is different from adding a larger lumped capacitance device. The increase in distributed capacitance will not lead to a deterioration of the resonance condition. The antenna structure can maintain a higher gain in the low frequency band. Specifically, for the resonance at 698MHz, the corresponding wavelength λ is approximately 430mm. The length L of the antenna structure in this application is 40mm, so the length of the antenna structure is approximately 0.093λ.

[0093] In the prior art, the length of the IFA and left-hand antenna in the B28 frequency band is generally 0.2λ, that is, about 86mm. Obviously, compared with the current IFA and left-hand antenna, the antenna structure of the present application is easier to achieve a short configuration, occupies a shorter layout length, and makes it easier for electronic devices to layout more LB antennas under the existing metal frame length conditions.

[0094] In the prior art, a lumped capacitor can be connected across the slot of the ICE antenna or in series at the feeding point to increase the capacitance value so that the antenna works in the low frequency band. However, since the above method increases the lumped capacitance instead of the distributed capacitance, as the capacitance value increases, the resonance of the antenna structure will become shallower, that is, the input power at the resonant frequency will decrease. For example, simulation tests show that under the same antenna specifications, when the lumped capacitance value of the high ICE antenna in the prior art is increased by 3.2pF, the gain at 780MHz is -1.36dB, which means that more matching devices are needed to improve this poor matching. Figure 5 The antenna structure of the present application adopts a 16.8mm second branch 24, and the gain of the resonance at 780MHz can reach -26dB. The increase in distributed capacitance does not lead to an increase in the antenna reflection power. Therefore, the antenna structure of the present application has good resonance stability.

[0095] In a possible implementation, the second branch may include a second fixing portion and a second extending portion, which is described in detail below with reference to the accompanying drawings.

[0096] See also Figure 6 , which is a schematic diagram of another antenna structure provided in an embodiment of the present application.

[0097] In this implementation, the second branch 24 includes a second fixing portion 241 and a second extending portion 242. One end of the second fixing portion 241 is connected to the first portion of the first side wall, and the other end of the second fixing portion 241 is connected to the second extending portion 242, and the second extending portion 242 extends to be opposite to the second portion.

[0098] The second extension portion 242 includes a plurality of mutually separated adjustment portions 2421, and two adjacent adjustment portions 2421 are connected via a PIN diode 243. That is, the second extension portion 242 is divided into several blocks. The embodiment of the present application does not specifically limit the width of the separating slits. For example, a 0.5 mm slit can be used to separate the second extension portion 242. The PIN diode 243 is connected across the two ends of each slit. By controlling the conduction or disconnection of the PIN diode 243, the length of the second extension portion 242 can be controlled, that is, the size of the distributed capacitance can be controlled. Through the above implementation method, the operating frequency of the antenna structure can be dynamically adjusted, so that the antenna structure can expand the supported frequency band, thereby improving practicality.

[0099] The above embodiments illustrate the principle and implementation of the antenna structure when used as an LB antenna. The following describes the implementation of the antenna structure when used as a Wi-Fi antenna.

[0100] Taking a tablet computer as an example, the radiator of the antenna structure can be the metal floor of the tablet computer. In this case, the antenna structure is directly embedded in the metal floor. Figure 3 No clearance is required in the X and Y directions as shown.

[0101] The metal floor is relatively large, so the key issue to consider is the directivity of the antenna.

[0102] The directivity coefficient is the ratio of the radiation intensity of the antenna in a certain direction to the radiation intensity of an ideal point source antenna in the same direction under the same radiation power conditions. The directivity coefficient can quantitatively describe the concentration of the antenna radiation energy. The size of the directivity coefficient can be intuitively observed in the antenna radiation pattern: the narrower the main lobe, the larger the directivity coefficient, and the stronger the antenna directivity. In this scenario, it is generally hoped that the antenna structure has a lower directivity coefficient, thereby ensuring that the tablet has good communication capabilities at any angle.

[0103] See also Fig. 7A and Figure 7B . Figure 7B A schematic diagram of another antenna structure provided in an embodiment of the present application.

[0104] In the embodiment of the present application, the radiator of the antenna structure is taken as the metal floor of the tablet computer. The area specifications of the metal floor are: 160mm wide, 240mm long, and 3mm high. The antenna structure is located in the middle of the side of the metal floor. The specific size specifications of the antenna structure are as follows:

[0105] Length L0=16mm, width W=2mm, height H=3.0mm; the second branch node is L-shaped, the height of the second branch node is equal to the height H of the groove ring structure, and the distance between the second branch node and the second part of the first side wall D1=0.7mm; the length of the first branch node 23 is 4.3mm, and the distance between the first branch node and the second side wall D2=0.6mm.

[0106] By changing the length of the second branch, the size of the distributed capacitance of the antenna structure can be changed, thereby changing the resonant frequency of the antenna structure. For details, see Figure 8 shown.

[0107] See also Figure 8 , which is a schematic diagram of the simulation results provided by the embodiment of the present application Figure 2 .

[0108] When the length of the second branch starts from 0 and takes values ​​of 1.3mm, 2.3mm, 3.3mm, 4.8mm, 5.3mm, and 5.8mm in sequence, the resonant frequency of the antenna structure changes from 4130MHz to 3660MHz, 3181MHz, 2820MHz, 2564MHz, 2452MHz, and 2268MHz in sequence. Every increase of 1mm in the length of the second branch will cause the resonant frequency to drop by several hundred megahertz. Therefore, the tuning range of the antenna structure of the solution of the present application is very large, and the depth gain of the resonance is basically maintained at about -20dB.

[0109] See also Fig. 9 , which is a schematic diagram of the simulation results provided by the embodiment of the present application Figure 3 .

[0110] The antenna structure also has a good efficiency bandwidth. When the length of the second branch is 2.3mm, the efficiency bandwidth is 318MHz and the relative bandwidth is 10%. When the length of the second branch is 5.3mm, the resonance drops to 2452MHz, the efficiency bandwidth is 112MHz and the relative bandwidth is 4.6%, which is enough to cover the Wi-Fi 2.4GHz frequency band.

[0111] Under the condition of a large-scale metal base plate, the existing antenna will produce a relatively high directivity coefficient, for example, the directivity coefficient of the existing antenna can reach 6-7dBi. The embodiment of the present application tests and simulates the directivity coefficient of the antenna structure, which is described in detail below.

[0112] See also Fig.10 , which is a fourth schematic diagram of the simulation results provided in an embodiment of the present application.

[0113] In the Wi-Fi 2.4GHz frequency band, when the dimensions of the metal floor are 160mm long, 100mm wide, and 3mm high, the directivity coefficient of the antenna structure is 2.307dBi.

[0114] See also Fig.11 , which is a schematic diagram of the simulation results provided by the embodiment of the present application Figure 5 .

[0115] In the Wi-Fi 2.4GHz frequency band, when the dimensions of the metal floor are 240mm long, 160mm wide, and 3mm high, the directivity coefficient of the antenna structure is 3.790dBi.

[0116] See also Fig.12 , which is a schematic diagram of the simulation results provided by the embodiment of the present application Figure 6 .

[0117] In the Wi-Fi 2.4GHz band, when the metal floor is 300mm long, 200mm wide, and 3mm high, the directivity coefficient of the antenna structure is 3.802dBi. It can be found that although the size of the metal floor continues to increase, the increase in the directivity coefficient is small. The simulation test also found that after further increasing the size of the metal floor, the directivity coefficient will hardly continue to increase.

[0118] See also Fig.13 , which is a schematic diagram of the principle provided by the embodiment of the present application Figure 2 .

[0119] The antenna structure of the embodiment of the present application can achieve a low directivity coefficient because: the antenna structure of the present application can achieve a short configuration, and the length of the antenna structure is relatively short, so the position of the antenna structure can be as close to the center line of the metal floor as possible, so that the current excited by the antenna structure on the metal bottom plate is a transverse wave, such as Fig.13 13(A) in FIG. However, the length of a conventional antenna is generally long, and one end of the antenna is often too close to the top edge or the ground edge of the metal floor, such as Fig.13 As shown in 13(B) in the figure, the antenna structure will excite a longitudinal current on the metal base plate. The longitudinal current will form multiple half-wave current distributions on the floor. The longitudinal current is equivalent to multiple half-waves, which is equivalent to the superposition of multiple antenna fields. This results in a narrow beam, that is, a high directivity coefficient, which leads to the deterioration of the antenna pattern.

[0120] Since the length of the antenna structure in the embodiment of the present application is relatively short, it can be set at most positions on the side of the metal floor. However, in actual applications, in order to reduce the directivity coefficient, it can be located in the middle of the side of the metal floor as much as possible. After testing and simulation, the recommended minimum distance between the setting position of the antenna structure given in the embodiment of the present application and the top or bottom edge of the metal floor is 30mm, so that the directivity coefficient can be maintained at 5dBi. It can be understood that the above distance recommendation value does not constitute a limitation on the technical solution of the present application.

[0121] The above embodiments illustrate the implementation of the antenna structure as a Wi-Fi antenna for larger electronic devices such as tablet computers. In the above implementation, the radiator of the antenna structure can directly use the metal floor or metal frame of the electronic device, and does not need to be separated by clearance from the metal floor and metal frame of the electronic device, thereby reducing the clearance requirements in the X and Y directions.

[0122] The following describes how to implement the antenna structure when it is applied to smaller wearable devices such as smart watches and wireless headphones.

[0123] See also Fig.14, which is a schematic diagram of another antenna structure provided in an embodiment of the present application.

[0124] In the embodiment of the present application, the radiator of the antenna structure is stacked with the metal floor of the electronic device, and the first side wall of the antenna structure is parallel to the metal bottom plate, and the second side wall is parallel to the metal floor.

[0125] Fig.14 The area specifications of the middle metal floor are: 15mm wide, 30mm long, and 1mm high. The antenna structure is located in the middle of the side of the metal floor. The specifications of the antenna structure are as follows:

[0126] Length L = 16 mm, width W = 2.0 mm, height H = 1.0 mm, the dielectric constant ε of the dielectric material of the antenna in the slot ring structure r =4.2, the dielectric loss of the material tanδ=0.005; the second branch is L-shaped, and the height of the second branch is equal to the height H of the groove ring structure.

[0127] The radiator of the antenna structure can be directly stacked on the metal floor of the electronic device without the need for a clearance between the radiator and the metal floor, thereby reducing the clearance requirement in the Y direction.

[0128] See also Fig.15 , which is schematic diagram seven of the simulation results provided in the embodiment of the present application.

[0129] The antenna structure in the prior art is limited by the size of the metal floor and has the problems of low efficiency and narrow bandwidth.

[0130] Fig.15 The simulation results of the antenna structure as a Wi-Fi antenna show that the antenna structure of the present application can maintain a good efficiency bandwidth without any matching device being set at the port, and the radiation efficiency within the band can reach above -5.5dB, so the radiation efficiency is relatively high.

[0131] In the above embodiments, dielectric material can be filled in the slot ring of the antenna structure. For example, for the frame antenna of a mobile phone, the dielectric material can be attached to the material of the nano injection molding. The electrical properties of the dielectric can be expressed by the dielectric constant ε r and its dielectric loss tanδ.

[0132] See also Fig.16 , which is a schematic diagram of another antenna structure provided in an embodiment of the present application.

[0133] The slot ring structure of the antenna structure includes a first area and a second area.

[0134] The first region includes the region between the second branch 23 and the first sidewall. Specifically, the first region includes the region between the first portion 26 of the second branch 23, the region between the second branch 23 and the second portion 27, and the region between the second branch 23 and the gap. The first region is filled with dielectric material 31.

[0135] The rest of the area in the slot ring structure except the first area is a second area, and the second area is filled with a magneto dielectric substrate 32 .

[0136] See also Fig.17 , which is a schematic diagram of the principle provided by the embodiment of the present application Figure 3 .

[0137] The magnetic field H generated by the circular current, the larger the magnetic field H, the larger the inductance L; the magnetic permeability μ r The larger it is, the greater the inductance.

[0138] The magnetoelectric material 32 is a material having a good dielectric constant ε r And the magnetic permeability μ r The introduction of magnetoelectric material can improve the radiation efficiency of the antenna, increase the bandwidth and reduce the size of the antenna. r , thus the inductance L of the antenna structure can be increased, so that the resonant frequency of the antenna structure is further reduced.

[0139] If only dielectric material is filled in the slot ring structure, the scaling factor of the antenna is By using the dielectric constant ε r Although a larger dielectric material can reduce the size of the antenna, it will lead to a deterioration in antenna efficiency and bandwidth. In the solution of the embodiment of the present application, the dielectric material 31 is filled in the second area, so that the antenna scaling factor is By choosing the magnetic permeability μ r Larger magnetoelectric materials can increase the bandwidth and radiation efficiency of the antenna while reducing its size.

[0140] Continue to see Fig.16 In the embodiment of the present application, the radiator of the antenna structure is stacked with the metal floor of the electronic device, and the first side wall of the antenna structure is parallel to the metal base plate, and the second side wall is parallel to the metal floor.

[0141] Fig.16 The area specifications of the middle metal floor are: 12mm wide, 30mm long, and 1mm high. The antenna structure is located in the middle of the side of the metal floor. The specifications of the antenna structure are as follows:

[0142] Length L = 12 mm, width W = 2.0 mm, height H = 1.0 mm, the dielectric constant ε of the dielectric material 31 r =3.2, the dielectric loss tanδ of the dielectric material 31 is 0.005; the second branch is L-shaped, and the height of the second branch is equal to the height H of the slot ring structure; the dielectric constant ε of the magnetoelectric material 32 r =3, magnetic permeability μ r =3, dielectric loss tanδe=0.01, magnetic loss tanδm=0.01.

[0143] Then Fig.16 The antenna structure shown is simulated.

[0144] See also Fig.18 and Fig.19 .in, Fig.18 The simulation results provided in this embodiment are shown in FIG. Figure 8 , Fig.19 A Smith chart of the antenna structure provided in an embodiment of the present application.

[0145] Depend on Fig.19 It can be seen that by filling the magnetoelectric material, the inductance is increased, thereby achieving the purpose of reducing the size of the antenna. The length of the antenna structure can be reduced from 16mm to 12mm, which is a 25% reduction, while maintaining the same radiation efficiency as a 16mm long antenna. At the same time, the dielectric constant ε can be filled in the first area. r The dielectric material 31 is lower. For example, the dielectric constant ε r It drops from 4.2 to 3.2, but the resonant frequency remains unchanged and is still around 2440MHz, which facilitates the selection of dielectric materials.

[0146] When the antenna structure of the present application is used as a Wi-Fi 2.4GHz antenna, the wavelength corresponding to the resonant frequency is approximately 125mm, while the length of the antenna structure is 12mm and the antenna length is 0.096λ. Compared with the design scheme of the antenna structure of 0.2λ in the prior art, the scheme of the present application realizes a short configuration design of the antenna structure.

[0147] Other implementations of the antenna structure are described below.

[0148] In the above embodiment, the second branch of the antenna structure is L-shaped, the first end of the second branch is connected to the first part of the first side wall, and the second end extends in the direction of the second side wall, so that part of the second branch is opposite to the second part of the first side wall. In addition, the second branch can also be folded back, which is described in detail below with reference to the accompanying drawings.

[0149] See also Fig. 20 , which is a schematic diagram of another antenna structure provided in an embodiment of the present application.

[0150] Fig. 20 The first branch is not shown. Fig. 20 The second branch 24 includes a folding portion 244, which is used to change the extension direction of the second branch 24. For example, the folding portion 244 in the figure adjusts the extension direction of the second branch 24 from away from the gap 25 to toward the gap 25.

[0151] Fig. 20 In the example, the extending direction of the second branch 24 is reversed by a folding portion 244 . In actual applications, the second branch 24 may be folded back multiple times or rotated back.

[0152] See also Fig.21 , which is a schematic diagram of another antenna structure provided in an embodiment of the present application.

[0153] like Fig.21 As shown in the side view, the second branch 24 includes two folded portions 244, which change the extension direction of the second branch 24 twice.

[0154] In the embodiment of the present application, the second branch is folded back so that the second branch can form a plurality of distributed capacitors connected in parallel with the second portion 27 of the first side wall, thereby increasing the total capacitance. Since the total capacitance is increased in the form of parallel distributed capacitance, the capacitance of a single distributed capacitance can be reduced, which facilitates shortening the length S1 of the second branch, thereby shortening the length of the antenna structure, and thus facilitating the realization of a short configuration design of the antenna structure.

[0155] In the above embodiment, the antenna structure forms a parallel distributed capacitor by bending the second branch to face the second portion of the first side wall. In addition, the number of branches can be increased to achieve a change in the size of the capacitor.

[0156] See also Fig. 22 , which is a schematic diagram of another antenna structure provided in an embodiment of the present application.

[0157] The antenna structure in the figure further includes a third branch 41 , a first end of the third branch 41 is connected to the first portion 26 of the first side wall, and a second end of the third branch 41 extends to be opposite to the second portion 27 .

[0158] Fig. 22 The second branch 24 in the embodiment includes a second fixing portion 241 and a second extending portion 242. The third branch 41 includes a third fixing portion 411 and a third extending portion 412. The second fixing portion 241 is connected to the first portion 26 of the first side wall, and the third fixing portion 411 is connected to the first portion 26 of the first side wall.

[0159] The second fixing portion 241 is parallel to the third fixing portion 411 , and the second extending portion 242 is parallel to the third extending portion 412 .

[0160] By adding the third branch 41 , a distributed capacitor is formed between the third extension portion 412 of the third branch 41 and the second portion 27 . At this time, a distributed capacitor is also formed between the second extension portion 242 of the second branch 24 and the second portion 27 .

[0161] By forming multiple distributed capacitors connected in parallel, the capacitance is increased, so that the capacitance of a single distributed capacitor can be reduced, which facilitates shortening the length of the second branch and the third branch, and further shortens the length of the antenna structure, thus facilitating the realization of a short configuration design of the antenna structure.

[0162] In another possible implementation, the third branch may not be parallel to the second branch, or the third extension of the third branch and the second extension of the second branch may be gradual curved surfaces. The areas of the extensions of the two branches may be the same or different.

[0163] In the above embodiment, the second branch 24 is located inside the groove ring structure, that is, the second branch 24 extends to the area between the second portion of the first side wall and the second side wall. In another possible implementation, the second branch 24 can be arranged outside the groove ring structure, which is described in detail below with reference to the accompanying drawings.

[0164] See also Fig.23 , which is a schematic diagram of another antenna structure provided in an embodiment of the present application.

[0165] The second branch 24 is located outside the groove ring structure, the second fixing portion 241 of the second branch 24 is connected to the first portion of the first side wall, and the second extending portion 242 of the second branch 24 extends to be opposite to the second portion.

[0166] Fig.23 The arrangement position of the second branch 24 shown can be distributed in a mirror image with respect to the first side wall as the arrangement position of the above embodiment.

[0167] use Fig.23 In the implementation shown, the second branch 24 may also include one or more folding portions for changing the extension direction of the second branch.

[0168] In addition, the antenna structure may also include a third branch, and the third branch is arranged at a position similar to Fig. 22 The positions in are mirrored about the first side wall.

[0169] Arranging the second branch 24 outside the groove ring structure can reduce the difficulty of processing the antenna mechanism and facilitate fixing the third branch and the first side wall.

[0170] In each of the above embodiments, the feeding point of the antenna structure is located on the second side wall, the first branch is connected to the first end and connected to the feeding point, and the second end of the first branch extends to the area between the first part of the first side wall and the second side wall, thereby achieving coupled feeding. In addition to the coupled feeding method, a direct feeding method can also be selected, which is described in detail below with reference to the accompanying drawings.

[0171] See also Fig.24 , which is a schematic diagram of direct feeding of the antenna structure provided in an embodiment of the present application.

[0172] Fig.24 Only the first branch as the feeding branch is illustrated, and the second branch is not illustrated.

[0173] In one possible implementation, Fig.24 As shown in 24 (A) in FIG. 24 , the feeding point 29 is located on the second side wall, the first end of the first branch 23 is connected to the feeding point, and the second end of the first branch 23 is connected to the first part of the first side wall. At this time, the first branch is connected between the first side wall and the second side wall. This implementation method can shorten the length of the first branch 23.

[0174] In another possible implementation, Fig.24 As shown in FIG. 24 (B), the feeding point 29 is located on the second side wall, the first end of the first branch 23 is connected to the feeding point, and the second end of the first branch 23 is connected to the second part of the first side wall.

[0175] In another possible implementation, Fig.24 As shown in FIG. 24(C), the feeding point 29 is located at the first part of the first side wall, the first end of the first branch 23 is connected to the feeding point, and the second end of the first branch 23 is connected to the second part of the first side wall.

[0176] Based on the antenna structure provided in the above embodiments, an embodiment of the present application further provides an electronic device, which includes one or more antenna structures.

[0177] In one possible implementation, see Figure 4B and Figure 7B Correspondingly, the electronic device may be a mobile phone or a tablet computer, which has a relatively large metal floor, and the radiator of the antenna structure may be the metal floor of the electronic device.

[0178] In another possible implementation, the electronic device may be an electronic device such as a mobile phone or a tablet computer having a metal frame of a certain length, and the radiator of the antenna structure may be the metal frame of the electronic device.

[0179] In the above implementation, there is no need to add lumped components to the antenna structure, thus avoiding the problems of unstable resonance and narrow bandwidth of lumped components. In addition, there is no need to use long gaps to construct distributed capacitors, thus ensuring the beauty of the electronic equipment and the stability of the structure. In addition, the short antenna design can be realized, which reduces the need for clearance and facilitates antenna layout and increases the number of antennas.

[0180] In another possible implementation, see Fig.14 Correspondingly, the electronic device can be an electronic device with a small metal base plate and no long metal frame, such as a smart watch or a Bluetooth headset. In this case, the radiator of the antenna structure can be stacked on the metal floor of the electronic device. Preferably, the first side wall and the second side wall of the antenna structure are parallel to the metal floor. In this implementation, the antenna structure does not require clearance in the direction parallel to the plane where the metal floor is located, which can realize a short-configuration antenna design and reduce the need for clearance, facilitate antenna layout and increase the number of antennas.

[0181] It should be understood that in the present application, "at least one (item)" means one or more, and "plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items.

[0182] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. An antenna structure, characterized in that: include: Radiant, first branch and second branch; The radiator comprises a groove ring structure, a first side wall of the groove ring structure is provided with a gap, and the gap separates the first side wall into a first part and a second part; The first branch is located between the first side wall and the second side wall of the slot ring structure, the first branch is used for coupling a feeding point, the second side wall is located on an opposite side of the first side wall, and the feeding point is located on the first part or the second side wall; The second branch is connected to the first portion, and a portion of the second branch is opposite to the second portion.

2. The antenna structure according to claim 1, characterized in that: The groove ring structure is filled with a dielectric material.

3. The antenna structure according to claim 1, characterized in that: The slot ring structure includes a first region and a second region, the first region is filled with a dielectric material, the second region is filled with a magnetoelectric material, and the first region includes a region between the second branch and the first side wall.

4. The antenna structure according to claim 1, characterized in that: The second branch includes one or more folding parts, and the folding parts are used to change the extension direction of the second branch.

5. The antenna structure according to claim 1, characterized in that: The antenna structure further includes: a third branch; The third branch is connected to the first part, and a portion of the third branch is opposite to the second part.

6. The antenna structure according to claim 5, characterized in that: The second branch includes a second fixed portion and a second extending portion, the third branch includes a third fixed portion and a third extending portion, the second fixed portion and the third fixed portion are parallel, the second extending portion and the third extending portion are parallel, the second fixed portion is connected to the first portion, and the third fixed portion is connected to the first portion.

7. The antenna structure according to claim 1, characterized in that: The second branch node is located in the groove ring structure, and the second branch node extends to a region between the second portion and the second side wall.

8. The antenna structure according to claim 1, characterized in that: The second branch node is located outside the groove ring structure.

9. The antenna structure according to claim 1, characterized in that: The second branch comprises a second fixing portion and a second extending portion, and the second fixing portion is connected to the first portion; The second extension portion includes a plurality of mutually separated adjustment portions; Two adjacent adjustment parts are connected via a PIN diode.

10. The antenna structure according to any one of claims 1 to 9, characterized in that: The feeding point is located on the second side wall, the first end of the first branch is connected to the feeding point, and the second end of the first branch extends to the area between the first part and the second side wall.

11. The antenna structure according to any one of claims 1 to 9, characterized in that: The feeding point is located on the second side wall, the first end of the first branch is connected to the feeding point, and the second end of the first branch is connected to the first part.

12. The antenna structure according to any one of claims 1 to 9, characterized in that: The feeding point is located on the second side wall, the first end of the first branch is connected to the feeding point, and the second end of the first branch is connected to the second part.

13. The antenna structure according to any one of claims 1 to 9, characterized in that: The feeding point is located at the first part, the first end of the first branch is connected to the feeding point, and the second end of the first branch is connected to the second part.

14. An electronic device, characterized in that: The electronic device comprises one or more antenna structures according to any one of claims 1-13.

15. The electronic device according to claim 14, characterized in that: The radiator is a metal floor of the electronic device or a metal frame of the electronic device.

16. The electronic device according to claim 14, characterized in that: The radiator is stacked with a metal floor of the electronic device, and the first side wall and the second side wall of the antenna structure are parallel to the metal floor.

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