CN217641784U

CN217641784U - Antenna device and terminal equipment

Info

Publication number: CN217641784U
Application number: CN202222018906.9U
Authority: CN
Inventors: 马晓娜; 王落芬; 陈仁庆; 郑江伟; 丁市召
Original assignee: Hisense Mobile Communications Technology Co Ltd
Current assignee: Hisense Mobile Communications Technology Co Ltd
Priority date: 2022-08-02
Filing date: 2022-08-02
Publication date: 2022-10-21
Anticipated expiration: 2032-08-02

Abstract

The utility model relates to an antenna field discloses an antenna device and terminal equipment. An antenna device includes: the antenna comprises a substrate, a metal ground, a first antenna and a second antenna, wherein the metal ground, the first antenna and the second antenna are arranged on the substrate; the metal ground is provided with a first side edge, a second side edge and a third side edge, wherein the first side edge and the second side edge are oppositely arranged, and the third side edge is connected with the first side edge and the second side edge; the first antenna is positioned on one side of the metal far away from the second side edge and is connected with the first side edge; the second antenna is positioned on one side of the metal ground far away from the first side edge and connected with the second side edge; an isolation groove with an opening positioned on the third side edge is arranged in the metal ground, and an isolation structure used for improving the isolation degree is arranged in the isolation groove. The antenna device comprises the first antenna and the second antenna, the isolation groove is formed between the first antenna and the second antenna on the basis that the radiation performance of the antenna is not influenced, the isolation structure used for improving isolation degree is arranged in the isolation groove, and the requirement of high isolation degree between the double antennas can be met.

Description

Antenna device and terminal equipment

Technical Field

The utility model relates to an antenna technology field, in particular to antenna device and terminal equipment.

Background

With the explosive development of big data, the popularization of smart homes, the development of whole-house intelligent customization, and the era of everything interconnection has come. The antenna technology is used as the basis of the interconnection of everything, and the performance of the antenna technology is related to a plurality of indexes of the system, such as connection speed, transmission rate, connection stability and the like. In order to improve the user experience, a multi-antenna system (MIMO technology) has become a trend of design.

In the early mobile terminal system, only one antenna exists, the problem of mutual coupling of the antennas does not exist, and when the number of the antennas is increased, an isolation index is also an important parameter of the system. However, when two or more antennas operating at the same frequency band exist on the same circuit board, the antennas may interfere with each other. If the transmission signal of the first antenna happens to fall in the working frequency band of the second antenna, serious interference, namely mutual coupling of the antennas, can be generated. The antenna isolation is a physical quantity measuring the mutual coupling degree. For antennas with the same frequency, the mutual coupling phenomenon is particularly serious. If the isolation is not good, not only the antenna efficiency but also the effect of Multiple-Input Multiple-Output (MIMO) and the throughput of the system are affected.

SUMMERY OF THE UTILITY MODEL

The utility model discloses an antenna device and terminal equipment for improve the isolation between the antenna.

In order to achieve the above purpose, the utility model provides the following technical scheme:

in a first aspect, the present invention provides an antenna device, including: the antenna comprises a substrate, and a metal ground, a first antenna and a second antenna which are arranged on the substrate;

the metal ground is provided with a first side edge, a second side edge and a third side edge, wherein the first side edge and the second side edge are oppositely arranged, and the third side edge is connected with the first side edge and the second side edge; the first antenna is positioned on one side, far away from the second side edge, of the metal ground and is connected with the first side edge; the second antenna is positioned on one side of the metal ground far away from the first side edge and is connected with the second side edge;

the metal ground is provided with an isolation groove with an opening positioned on the third side edge, and an isolation structure used for improving isolation degree is arranged in the isolation groove.

The antenna device comprises the first antenna and the second antenna, the isolation groove is formed between the first antenna and the second antenna on the basis that the radiation performance of the antenna is not influenced, the isolation structure used for improving isolation degree is arranged in the isolation groove, and the requirement of high isolation degree between the double antennas can be met.

In some embodiments, the isolation trench includes a first sidewall, a second sidewall, and a bottom wall connecting the first sidewall and the second sidewall, the first sidewall and the second sidewall each extending in a first direction, wherein the first direction is an extending direction of the first side edge;

the isolation structure comprises a first isolation branch knot and a second isolation branch knot which are symmetrically arranged at intervals, the first isolation branch knot is connected with the first side wall, and the second isolation branch knot is connected with the second side wall.

In some embodiments, the first spacer branch comprises a first spacer branch and a second spacer branch, the second spacer branch being connected to the first sidewall via the first spacer branch;

the second isolation branch node comprises a third isolation sub branch node and a fourth isolation sub branch node, and the fourth isolation sub branch node is connected with the second side wall through the third isolation sub branch node.

In some embodiments, the second and fourth isolator sub-branches both extend along the first direction, and the first and third isolator sub-branches extend along a second direction that is perpendicular to the first direction.

In some embodiments, the antenna device further comprises a third antenna located within the isolation slot, the third antenna comprising an antenna three feed stub, the first isolation stub, and the second isolation stub; and the first end of the three feeding branches of the antenna is connected with the metal ground feed, and the second end of the three feeding branches of the antenna is coupled with the first isolation branch and/or the second isolation branch.

In some embodiments, a first end of the three feed branches of the antenna is in feed connection with the bottom wall, and a second end extends between the first isolation branch and the second isolation branch; or,

the first end of the three feeding branches of the antenna is in feeding connection with the bottom wall, and the second end of the three feeding branches of the antenna extends to a position between the first isolation branch and the first side wall; or,

and the first end of the three feeding branches of the antenna is connected with the bottom wall in a feeding way, and the second end of the three feeding branches of the antenna extends to the position between the second isolation branch and the second side wall.

In some embodiments, a first end of the antenna's three feed stub is in feed connection with the first sidewall, the third antenna further comprises a first coupling stub, a second end of the antenna's three feed stub is in perpendicular connection with the first end of the first coupling stub, the second end of the first coupling stub extends between the second isolation stub and the second sidewall, or,

the first end of the three feeding branches of the antenna is electrically connected with the second side wall in a feeding mode, the third antenna further comprises a second coupling branch, the second end of the three feeding branches of the antenna is perpendicularly connected with the first end of the second coupling branch, and the second end of the first coupling branch extends to the first isolation branch and the first side wall.

In some embodiments, the first antenna and/or the second antenna comprises: the antenna comprises a feed branch, a first antenna branch, a second antenna branch, a third antenna branch, a grounding branch and a parasitic branch;

the first end of the feed branch is connected with the metal ground feed, the second end of the feed branch is connected with the first end of the first antenna branch and forms a first bending angle at the connection position, the second end of the first antenna branch is connected with the first end of the second antenna branch and forms a second bending angle at the connection position, the second end of the second antenna branch is connected with the first end of the third antenna branch and forms a third bending angle at the connection position, the second end of the third antenna branch is coupled with the first end of the parasitic branch, and the second end of the parasitic branch is connected with the metal ground;

the first antenna stub is further connected with the metal ground through the grounding stub and forms a fourth bent angle at the connection position.

In some embodiments, the parasitic branch comprises a first parasitic sub-branch and a second parasitic sub-branch, and a second end of the second parasitic sub-branch is connected to the metal ground through the first parasitic sub-branch and forms a fifth bend angle at the connection.

In a second aspect, the present invention further provides a terminal device, including the antenna apparatus according to any one of the first aspect.

Drawings

Fig. 1 is a schematic structural diagram of an antenna apparatus according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of another antenna apparatus according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of another antenna device according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of another antenna apparatus according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of another antenna device according to an embodiment of the present invention;

FIG. 6 is a radiation waveform diagram of the antenna device of FIG. 5;

FIG. 7 is a schematic diagram of a current distribution of a first antenna of the antenna apparatus of FIG. 5;

FIG. 8 is a schematic diagram of a current distribution of a second antenna of the antenna apparatus of FIG. 5;

FIG. 9 is a graph comparing the isolation between the antenna device of FIG. 5 and a dual antenna without isolation structures;

fig. 10 is a schematic structural diagram of another antenna device according to an embodiment of the present invention;

fig. 11 is a schematic structural diagram of another antenna apparatus according to an embodiment of the present invention;

fig. 12 is a schematic structural diagram of another antenna device according to an embodiment of the present invention;

fig. 13 is a schematic diagram of the radiation performance of the third antenna under different feeding positions;

fig. 14 is a schematic structural diagram of another antenna device according to an embodiment of the present invention;

fig. 15 is a schematic structural diagram of another antenna device according to an embodiment of the present invention;

FIG. 16 is a schematic current distribution diagram of the antenna device of FIG. 10;

FIG. 17 is a schematic diagram of current distribution in the antenna device of FIG. 14;

FIG. 18 is a schematic current distribution diagram of the antenna device of FIG. 15;

fig. 19 is a schematic structural diagram of another antenna device according to an embodiment of the present invention;

fig. 20 is a schematic structural diagram of another antenna device according to an embodiment of the present invention;

fig. 21 is a schematic structural diagram of another antenna device according to an embodiment of the present invention.

An icon: 100-a substrate; 200-metal ground; 300-a first antenna; 400-a second antenna; 500-an isolation trench; 600-an isolation structure; 210-a first side; 220-a second side edge; 230-third side; 240-fourth side; 310-feed branch; 320-a first antenna branch; 330-second antenna minor matters; 340-a third antenna branch; 350-grounded branch knot; 360-parasitic branch knot; 361-first parasitic minor branch; 362-second parasitic subcircuit; 410-feed branch; 420-first antenna branch; 430-a second antenna stub; 440-a third antenna knuckle; 450-ground branch; 460-parasitic branch knots; 461-first parasitic subcircuit; 462-a second parasitic sub-branch; 510-a first sidewall; 520-a second side wall; 530-a bottom wall; 610-first isolated branch; 620-second isolated branch; 611-first spacer branch; 612-second isolator dendron; 621-third insulator branch; 622-fourth insulator branch; 710-antenna three feed stub; 720-a first coupling branch; 730-a second coupling branch; 740-a third coupling branch; 750-fourth coupling branch; 760-fifth coupling branch.

Detailed Description

The isolation is usually reduced by increasing the distance between the antennas or adding a separation wall between the antennas to increase the matching decoupling, but this method is not suitable for miniaturized PCB (Printed circuit board) antennas, and the increase of matching also increases the cost.

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

In a first aspect, as shown in fig. 1, an embodiment of the present invention provides an antenna apparatus, including: a substrate 100, and a metal ground 200, a first antenna 300, and a second antenna 400 provided on the substrate 100; the metal ground 200 has a first side 210 and a second side 220 oppositely disposed and a third side 230 connecting the first side 210 and the second side 220; the first antenna 300 is located on the side of the metal ground 200 away from the second side 220 and connected to the first side 210; the second antenna 400 is located on the side of the metal ground 200 far away from the first side 210, and is connected to the second side 220; the metal ground 200 is provided with an isolation groove 500 opened at the third side 230, and an isolation structure 600 for improving isolation is provided in the isolation groove 500.

The antenna device comprises the first antenna 300 and the second antenna 400, and on the basis that the radiation performance of the antennas is not influenced, the isolation groove 500 is arranged between the first antenna 300 and the second antenna 400, and the isolation structure 600 used for improving the isolation degree is arranged in the isolation groove 500, so that the requirement of high isolation degree between the two antennas can be met.

In one possible implementation manner, the substrate 100 may be a PCB, the metal ground 200 includes a first side 210, a second side 220, a third side 230, and a fourth side 240, and the first side 210, the third side 230, the second side 220, and the fourth side 240 are sequentially connected end to form a quadrilateral, for example, the first side 210 and the second side 220 both extend along a first direction (X direction in fig. 1), the third side 230 and the fourth side 240 both extend along a second direction (Y direction in fig. 1), and the first direction is perpendicular to the second direction. It can be understood that the orthographic projection of the metal ground 200 on the substrate 100 is rectangular, i.e. the metal ground 200 is an axisymmetric pattern. It should be noted that the specific structure of the first antenna 300 and the second antenna 400 is not limited to the structure shown in fig. 1.

It should be noted that, since the current distribution of the antenna device is strongest at the edge of the metal ground 200, and the middle position of the metal ground 200 is the current zero point, the slot processing is performed at the middle position of the metal ground 200, and the radiation performance of the antenna device is not affected, for example, as shown in fig. 1, the first antenna 300 is located at the left side of the metal ground 200, the second antenna 400 is located at the right side of the metal ground 200, the isolation slot 500 is located at the middle of the metal ground 200, and the opening is located at the third side 230.

In some embodiments, the isolation trench 500 includes a first sidewall 510, a second sidewall 520, and a bottom wall 530 connecting the first sidewall 510 and the second sidewall 520, the first sidewall 510 and the second sidewall 520 each extending along a first direction, wherein the first direction is an extending direction of the first side edge 210; the isolation structure 600 includes a first isolation branch 610 and a second isolation branch 620 that are symmetrically and spaced, the first isolation branch 610 is connected to the first sidewall 510, and the second isolation branch 620 is connected to the second sidewall 520.

In one possible implementation, with continued reference to fig. 1, the opening of the isolation trench 500 is located at the third side 230, the isolation trench 500 includes a first sidewall 510, a second sidewall 520, and a bottom wall 530 connecting the first sidewall 510 and the second sidewall 520, the first sidewall 510 and the second sidewall 520 both extend along a first direction (X direction in fig. 1), and the bottom wall 530 extends along a second direction (Y direction in fig. 1), that is, the isolation trench 500 is a U-shaped trench. The axis of the isolation groove 500 is AA ', a first isolation branch 610 and a second isolation branch 620 symmetrical with respect to AA' are arranged in the isolation groove 500, and the first isolation branch 610 and the second isolation branch 620 are arranged at intervals, that is, an air region is arranged between the first isolation branch 610 and the second isolation branch 620. The first isolation branch 610 and the second isolation branch 620 may be equivalent to a capacitor structure, that is, the antenna apparatus sets the isolation structure 600 in the isolation slot 500, which is equivalent to a series capacitor in the isolation slot 500, and by adjusting the relative positions and the optimization of the parameters such as the size of the first isolation branch 610 and the second isolation branch 620, the equivalent distribution capacitance of the isolation structure 600 may be adjusted, the isolation of the antennas is optimized, the mutual coupling between the first antenna 300 and the second antenna 400 is reduced, and the requirement of high isolation between the two antennas is met.

In some embodiments, first isolation branch 610 includes first isolator branch 611 and second isolator branch 612, second isolator branch 612 being connected to first sidewall 510 by first isolator branch 611; the second isolation branch 620 includes a third isolation sub-branch 621 and a fourth isolation sub-branch 622, and the fourth isolation sub-branch 622 is connected to the second sidewall 520 through the third isolation sub-branch 621.

In one possible implementation, with continued reference to fig. 1, first isolation branch 610 includes a first isolator branch 611 and a second isolator branch 612, where a first end of first isolator branch 611 is connected to first sidewall 510, and a bend angle is formed at the connection; the second end of first spacer branch 611 is connected to the first end of second spacer branch 612, and a bending angle is formed at the connection; that is, the first isolation branch 610 has an L-shaped structure. The second spacer branch 620 includes a third spacer branch 621 and a fourth spacer branch 622, the first end of the third spacer branch 621 is connected to the second sidewall 520, and a bending angle is formed at the connection; the second end of the third spacer branch 621 is connected to the first end of the fourth spacer branch 622, and a bending angle is formed at the connection; that is, the second isolation branch 620 has an L-shaped structure, and the L-shaped first isolation branch 610 and the L-shaped second isolation branch 620 are symmetrical with respect to AA'.

In some embodiments, second and fourth isolator sub-branches 612, 622 each extend in a first direction, and first and third isolator sub-branches 611, 621 extend in a second direction, the second direction being perpendicular to the first direction.

In one possible implementation, with continued reference to fig. 1, the second spacer branch 612 and the fourth spacer branch 622 both extend along a first direction (X direction in fig. 1), and the first spacer branch 611 and the third spacer branch 621 extend along a second direction (Y direction in fig. 1); the first sidewall 510 and the second sidewall 520 both extend along the first direction (X direction in fig. 1), that is, the first spacer branch 611 and the third spacer branch 621 are both connected to the metal ground 200 perpendicularly, and the second spacer branch 612 and the fourth spacer branch 622 are both parallel to the first sidewall 510 and the second sidewall 520 of the isolation trench 500.

It can be understood that when the size of the isolation trench 500 is confirmed, the lengths of the first spacer branch 611 and the third spacer branch 621 determine the distance between the left and right spacer branches (i.e. the first spacer branch 610 and the second spacer branch 620). When current flows through the second isolator branch 612 and the fourth isolator branch 622 of the parallel metal ground 200, the second isolator branch 612 and the fourth isolator branch 622 are equivalent to a capacitor structure with the air structure in the middle, and the distance d between the two metal plates of the equivalent capacitor is adjusted by adjusting the sizes of the first isolator branch 611 and the third isolator branch 621; by optimizing the sizes of the second isolator sub-branch 612 and the fourth isolator sub-branch 622, the area S of the equivalent capacitor can be optimized, and thus the equivalent capacitance value can be optimized. From system analysis, adding the isolation structure 600 at the position of the isolation trench 500 is equivalent to connecting a capacitor in series at the position of the isolation trench 500. According to the capacitance formula:

wherein: epsilon is the dielectric constant of the medium between the plates, S is the opposite area of the capacitor polar plate, d is the distance of the capacitor polar plate, and k is the constant of the electrostatic force;

adjusting d and S can affect the value of C.

When the signal is fed in, the currents of the second isolation sub-branch 612 and the fourth isolation sub-branch 622 are reversed, the mutual coupling between the first antenna 300 and the second antenna 400 is suppressed by the surface wave generated by the current path of the isolation structure 600, and the loop path of the antenna on the metal ground 200 is changed, so that the isolation effect is improved.

It can be understood that the first antenna 300 and the second antenna 400 may be co-frequency antennas, in order to improve the isolation between the two antennas, an isolation groove 500 is formed in the metal ground 200 between the two antennas, an isolation structure 600 is added in the isolation groove 500, and by optimizing the isolation structure 600, the isolation between the antennas is improved without changing the structural size of the whole antenna, the size of the antenna, or the radiation performance of the antenna.

In a possible implementation manner, on a miniaturized PCB, two WiFi antennas with the same frequency are designed by using a design principle of an IFA antenna (Inverted-fantnna, inverted-F antenna), and an antenna frequency band can meet requirements of a WiFi 11b system and a BT (Bit Torrent) transmission bandwidth.

In one possible implementation manner, referring to fig. 2, the first antenna 300 includes a feeding branch 310, a first antenna branch 320, a second antenna branch 330, a third antenna branch 340, and a grounding branch 350, a first end of the feeding branch 310 is connected to the metal ground 200, a second end of the feeding branch 310 is connected to a first end of the first antenna branch 320 and forms a first bending angle at the connection, a second end of the first antenna branch 320 is connected to a first end of the second antenna branch 330 and forms a second bending angle at the connection, a second end of the second antenna branch 330 is connected to a first end of the third antenna branch 340 and forms a third bending angle at the connection, and the first antenna branch 320 is further connected to the metal ground 200 through the grounding branch 350 and forms a fourth bending angle at the connection. Illustratively, the feed branch 310, the second antenna branch 330, and the ground branch 350 all extend along the second direction (Y direction in fig. 2), and the first antenna branch 320 and the third antenna branch 340 all extend along the first direction (X direction in fig. 2), that is, the first bending angle, the second bending angle, the third bending angle, and the fourth bending angle are right angles.

With continued reference to fig. 2, the second antenna 400 includes a feeding branch 410, a first antenna branch 420, a second antenna branch 430, a third antenna branch 440, and a grounding branch 450, wherein a first end of the feeding branch 410 is in feeding connection with the metal ground 200, a second end is connected with a first end of the first antenna branch 420 and forms a first bent angle at the connection, a second end of the first antenna branch 420 is connected with a first end of the second antenna branch 430 and forms a second bent angle at the connection, a second end of the second antenna branch 430 is connected with a first end of the third antenna branch 440 and forms a third bent angle at the connection, and the first antenna branch 420 is further connected with the metal ground 200 through the grounding branch 450 and forms a fourth bent angle at the connection. Illustratively, the feed stub 410, the second antenna stub 430, and the ground stub 450 all extend along the second direction (Y direction in fig. 2), and the first antenna stub 420 and the third antenna stub 440 all extend along the first direction (X direction in fig. 2), that is, the first bent angle, the second bent angle, the third bent angle, and the fourth bent angle are all right angles.

It should be noted that, taking the first antenna 300 as an example, the grounding branch 350 is added on the positive side of the feeding branch 310 of the first antenna 300 close to the X axis, so that the input impedance of the monopole antenna is changed, the impedance smith chart of the antenna rotates counterclockwise, which is equivalent to a parallel inductance, and at the same operating frequency, the radiation length of the antenna is reduced, thereby realizing the miniaturization of the antenna.

With continued reference to fig. 2, the isolation slot 500 between the first antenna 300 and the second antenna 400 extends in a first direction (X direction in fig. 2), and in the isolation structure 600: the first isolator branch 611 and the third isolator branch 621 are located on the same straight line and both extend along the second direction (Y direction in fig. 2), and the second isolator branch 612 and the fourth isolator branch 622 both extend along the first direction (X direction in fig. 2), that is, the second isolator branch 612 and the fourth isolator branch 622 are both perpendicular to the feeding directions of the first antenna 300 and the second antenna 400.

In some embodiments, the first antenna 300 and/or the second antenna 400 comprise: the antenna comprises a feed branch, a first antenna branch, a second antenna branch, a third antenna branch, a grounding branch and a parasitic branch; the first end of the feed branch is in feed connection with the metal ground 200, the second end of the feed branch is connected with the first end of the first antenna branch and forms a first bending angle at the connection position, the second end of the first antenna branch is connected with the first end of the second antenna branch and forms a second bending angle at the connection position, the second end of the second antenna branch is connected with the first end of the third antenna branch and forms a third bending angle at the connection position, the second end of the third antenna branch is coupled with the first end of the parasitic branch, and the second end of the parasitic branch is connected with the metal ground 200; the first antenna stub is further connected to the metal ground 200 via the ground stub and a fourth bent angle is formed at the connection.

In one possible implementation, in order to optimize the radiation efficiency of the antenna, the feeding branch 310 in the first antenna 300 is biased toward the negative side of the X axis to add a parasitic branch 360 of the antenna, as shown in fig. 3, and the parasitic branch 360 is coupled with the antenna. Specifically, the first antenna 300 includes a feeding branch 310, a first antenna branch 320, a second antenna branch 330, a third antenna branch 340, a grounding branch 350, and a parasitic branch 360, a first end of the feeding branch 310 is in feeding connection with the metal ground 200, a second end is connected with a first end of the first antenna branch 320 and forms a first bending angle at the connection, a second end of the first antenna branch 320 is connected with a first end of the second antenna branch 330 and forms a second bending angle at the connection, a second end of the second antenna branch 330 is connected with a first end of the third antenna branch 340 and forms a third bending angle at the connection, a second end of the third antenna branch 340 is coupled with the first end of the parasitic branch 360, and a second end of the parasitic branch 360 is connected with the metal ground 200; the first antenna stub 320 is also connected to the metal ground 200 via the ground stub 350 and forms a fourth bent angle at the connection. Illustratively, the feed branch 310, the second antenna branch 330, and the ground branch 350 all extend along the second direction (Y direction in fig. 3), and the first antenna branch 320 and the third antenna branch 340 all extend along the first direction (X direction in fig. 3), that is, the first bending angle, the second bending angle, the third bending angle, and the fourth bending angle are right angles. The end of the radiating branch is the strongest point of the electric field, and strong electric field coupling is formed between the end of the added parasitic branch 360 and the end of the third antenna branch 340, thereby enhancing the radiation efficiency of the first antenna 300.

In one possible implementation, in order to optimize the radiation efficiency of the antenna, the feeding branch 410 is provided with an antenna parasitic branch 460 in the second antenna 400, which is biased to the negative side of the X axis and is coupled to the antenna through the parasitic branch 460, as shown in fig. 3. Specifically, the second antenna 400 includes a feeding branch 410, a first antenna branch 420, a second antenna branch 430, a third antenna branch 440, and a grounding branch 450, wherein a first end of the feeding branch 410 is in feeding connection with the metal ground 200, a second end is connected with a first end of the first antenna branch 420 and forms a first bending angle at the connection, a second end of the first antenna branch 420 is connected with a first end of the second antenna branch 430 and forms a second bending angle at the connection, a second end of the second antenna branch 430 is connected with a first end of the third antenna branch 440 and forms a third bending angle at the connection, a second end of the third antenna branch 440 is coupled with a first end of the parasitic branch 460, and a second end of the parasitic branch 460 is connected with the metal ground 200; the first antenna stub 420 is also connected to the metal ground 200 via the ground stub 450 and forms a fourth bent corner at the connection. Illustratively, the feed stub 410, the second antenna stub 430, and the ground stub 450 all extend in the second direction (Y direction in fig. 4), and the first antenna stub 420 and the third antenna stub 440 all extend in the first direction (X direction in fig. 4), that is, the first bent angle, the second bent angle, the third bent angle, and the fourth bent angle are all right angles. The end of the radiating branch is the strongest point of the electric field, and strong electric field coupling is formed between the end of the added parasitic branch 460 and the end of the third antenna branch 440, so that the radiation efficiency of the second antenna 400 is enhanced, and the working frequency and bandwidth range of the second antenna 400 can meet the frequency bandwidth requirements of WiFi 11b and BT.

In a possible implementation manner, in order to optimize the radiation efficiency of the antenna, the antenna parasitic branch 360 is added to the first antenna 300, where the feed branch 310 is biased to the negative X-axis side, and the antenna parasitic branch 460 is added to the second antenna 400, where the feed branch 410 is biased to the negative X-axis side, as shown in fig. 5, the parasitic branch 360 is coupled to each antenna branch in the first antenna 300, and the parasitic branch 460 is coupled to each antenna branch in the second antenna 400.

In some embodiments, the parasitic branch includes a first parasitic sub-branch and a second parasitic sub-branch, and a second end of the second parasitic sub-branch is connected to the metal ground 200 through the first parasitic sub-branch and forms a fifth bending angle at the connection.

In one possible implementation, as shown in fig. 5, in the first antenna 300: the parasitic branch 360 includes a first parasitic sub-branch 361 and a second parasitic sub-branch 362, and a second end of the second parasitic sub-branch 362 is connected to the metal ground 200 through the first parasitic sub-branch 361 and forms a fifth bending angle at the connection. Illustratively, the first parasitic sub-branch 361 extends along the second direction (Y direction in fig. 5), and the second parasitic sub-branch 362 extends along the first direction (X direction in fig. 5), i.e. the fifth bending angle is a right angle. In the second antenna 400: the parasitic branch 460 includes a first parasitic sub-branch 461 and a second parasitic sub-branch 462, and a second end of the second parasitic sub-branch 462 is connected to the metal ground 200 through the first parasitic sub-branch 461, and a fifth bending angle is formed at the connection. Illustratively, the first parasitic sub-branch 461 extends along the second direction (Y direction in fig. 5), and the second parasitic sub-branch 462 extends along the first direction (X direction in fig. 5), that is, the fifth bending angle is a right angle.

With continued reference to fig. 5, a first gap is formed between the first end of the second parasitic sub-branch 362 and the end of the third antenna branch 340, a second gap is formed between the second parasitic sub-branch 362 and the first antenna branch 320, and a third gap is formed between the first parasitic sub-branch 361 and the first end of the first antenna branch 320; a fourth gap is formed between the first end of the second parasitic sub-branch 462 and the end of the third antenna branch 440, a fifth gap is formed between the second parasitic sub-branch 462 and the first antenna branch 420, and a sixth gap is formed between the first parasitic sub-branch 461 and the first end of the first antenna branch 420. It should be noted that parameters such as the lengths and widths of the first slot, the second slot, and the third slot in the first antenna 300 may affect the radiation intensity and the antenna efficiency of the first antenna 300, and parameters such as the lengths and the widths of the fourth slot, the fifth slot, and the sixth slot in the second antenna 400 may affect the radiation intensity and the antenna efficiency of the second antenna 400, and by optimizing the slots, the parasitic capacitance between the parasitic branch and the antenna may be optimized, so that the current distribution on the antenna is changed, and the radiation performance of the antenna is enhanced.

In a possible implementation manner, fig. 6 is a radiation waveform diagram of the first antenna 300 and the second antenna 400, and through optimization, the antenna operating frequency is 2.3 to 2.6GHz, which meets the operating bandwidth requirements of BT and WiFi 2.4G. Fig. 7 and 8 are current distribution diagrams of the first antenna 300 and the second antenna 400, respectively, and it can be seen that the current of the first parasitic sub-branch is opposite to the feeding current at the feeding position, so as to form a parasitic capacitance and enhance the radiation of the antenna; the current path of the second parasitic sub-branch is coupled with the antenna branch in the same direction, so that the electric field intensity at the tail end of the antenna is enhanced.

Fig. 9 is a comparison of the antenna isolation degrees of the isolation structure and the isolation structure, where the curve S2 marked as a circle and the curve 1' marked as a triangle are the antenna isolation degree curve of the isolation structure, and the curve S2 marked as a triangle and the curve 1 marked as the antenna isolation degree curve of the isolation structure, it is obvious that, after the isolation structure is added, the antenna isolation degree is optimized by more than 10dB, and after the isolation structure is added, in the working bandwidth of the antenna, the isolation degree can reach more than-20 dB, the mutual coupling influence between the antennas is reduced, and the antenna isolation degree curve has significant improvement effects on the transmission rate, throughput and the like of the system.

In some embodiments, the antenna apparatus further comprises a third antenna located within the isolation slot 500, the third antenna comprising an antenna three feed branch 710, a first isolation branch 610, and a second isolation branch 620; the first end of the three feeding branches 710 of the antenna is connected to the metal ground 200, and the second end is coupled to the first isolation branch 610 and/or the second isolation branch 620.

In a possible implementation manner, the antenna apparatus adds the antenna three-feeding branch 710 at the bottom position of the isolation slot 500, and when a signal is fed, the antenna three-feeding branch 710 forms magnetic coupling with the isolation structure 600 and the metal ground 200, so as to excite the radiation characteristic of the third antenna. The feeding point of the third antenna can be selected to different feeding point positions according to requirements, for example, the three feeding branches 710 of the antenna are connected with the bottom wall 530, or the three feeding branches 710 of the antenna are connected with the first sidewall 510, or the three feeding branches 710 of the antenna are connected with the second sidewall 520. A gap between the second isolator branch 612 and the fourth isolator branch 622 is a first position, a gap between the second isolator branch 612 and the first sidewall 510 is a second position, and a gap between the fourth isolator branch 622 and the second sidewall 520 is a third position, and the antenna three-feed branch 710 may be disposed at the first position, the second position, or the third position.

In some embodiments, as shown in fig. 10, the antenna triple-feed branch 710 extends along the second direction (Y direction in fig. 11), the first end of the antenna triple-feed branch 710 is in feeding connection with the bottom wall 530, and the second end extends between the first isolation branch 610 and the second isolation branch 620, that is, the antenna triple-feed branch 710 is located at the first position, and the antenna triple-feed branch 710 is exemplarily coincident with the axis AA' of the isolation slot 500. A seventh gap is formed between the three antenna feeding branch 710 and the first sidewall 510, an eighth gap is formed between the three antenna feeding branch 710 and the second isolator branch 612, and a ninth gap is formed between the three antenna feeding branch 710 and the fourth isolator branch 622. The seventh slot and the eighth slot have a large influence on the performance of the third antenna, and the widths of the seventh slot and the eighth slot can be adjusted by adjusting the widths of the three feeding branches 710 of the antenna. Meanwhile, stronger electric fields exist in the seventh gap and the eighth gap, and the radiation performance of the antenna can be enhanced through magnetic coupling. The length of the antenna's three feed branches 710 affects the coupling area between the feed and the second isolator sub-branch 612, and thus affects the radiation strength of the antenna.

In some embodiments, as shown in fig. 11, the antenna three-feeding branch 710 extends along the second direction (Y direction in fig. 11), a first end of the antenna three-feeding branch 710 is in feeding connection with the bottom wall 530, and a second end of the antenna three-feeding branch 710 extends between the first isolation branch 610 and the first sidewall 510, that is, the antenna three-feeding branch 710 is located at the second position.

In some embodiments, as shown in fig. 12, the antenna triple-feed branch 710 extends along the second direction (Y direction in fig. 11), a first end of the antenna triple-feed branch 710 is in feed connection with the bottom wall 530, and a second end of the antenna triple-feed branch 710 extends between the second isolation branch 620 and the second sidewall 520, that is, the antenna triple-feed branch 710 is located at the third position.

When a signal is fed from the bottom of the isolation slot 500, the feeding position of the signal, that is, the position of the three feeding branches 710 of the antenna, simultaneously affects the distance from the metal ground 200, and affects the coupling strength of the magnetic field, thereby affecting the radiation strength of the antenna and the antenna pattern. Simulation comparison is carried out on the three positions of the three feeding branches 710 of the antenna in fig. 10-12, and the radiation performance of the three feeding branches on the antenna is shown in fig. 13. The curve i for marking the triangle is a radiation performance curve of the antenna three-feed branch 710 at the first position, the curve ii for marking the circle is a radiation performance curve of the antenna three-feed branch 710 at the second position, and the curve iii for marking the square is a radiation performance curve of the antenna three-feed branch 710 at the third position.

It is understood that the feeding may also be selected on the left side of the isolation slot 500, i.e. the first sidewall 510, or the right side of the isolation slot 500, i.e. the second sidewall 520, and the routing form of the antenna and the position of the terminal of the antenna may be designed according to the requirement.

In some embodiments, as shown in fig. 14, the first end of the antenna three feed branch 710 is in feed connection with the first sidewall 510, the third antenna further includes a first coupling branch 720, the second end of the antenna three feed branch 710 is perpendicularly connected to the first end of the first coupling branch 720, and the second end of the first coupling branch 720 extends between the second isolation branch 620 and the second sidewall 520. In order to enhance the coupling strength between the signal feed line and the isolation branch, when the side feed is selected, the vertical antenna branch needs to be added, such as the first coupling branch 720 in fig. 14. The antenna three feeding branch 710 extends along the first direction (X direction in fig. 14), the first coupling branch 720 extends along the second direction (Y direction in fig. 14), and the second end of the first coupling branch 720 extends between the fourth isolator branch 622 and the second sidewall 520. A tenth gap is formed between the first coupling branch 720 and the fourth isolator branch 622, an eleventh gap is formed between the first coupling branch 720 and the second side wall 520, and gap coupling is formed between the three antenna feeding branches 710, the metal ground 200 and the fourth isolator branch 622.

In some embodiments, as shown in fig. 15, the first end of the antenna three feed branch 710 is in feed connection with the second sidewall 520, the third antenna further includes a second coupling branch 730, the second end of the antenna three feed branch 710 is perpendicularly connected with the first end of the second coupling branch 730, and the second end of the first coupling branch 720 extends between the first isolation branch 610 and the first sidewall 510. In order to enhance the coupling strength between the signal feed line and the isolation branch, when the side feed is selected, the vertical antenna branch needs to be added, such as the second coupling branch 730 in fig. 15. The antenna three-feed branch 710 extends along the first direction (X direction in fig. 15), the second coupling branch 730 extends along the second direction (Y direction in fig. 15), and the second end of the second coupling branch 730 extends between the second isolator branch 612 and the first sidewall 510. A twelfth gap is formed between the second coupling branch 730 and the first sidewall 510, a thirteenth gap is formed between the second coupling branch 730 and the second isolation branch 612, and gap coupling is formed between the three antenna feeding branches 710, the metal ground 200 and the second isolation branch 612, so that when a signal is fed, the currents of the three antenna feeding branches 710 and the isolation branches are reversed, and an electric field excites a magnetic field to couple out a resonant waveform of the antenna.

By adding the feeding signal of the third antenna at the position of the isolation slot 500, a gap is formed between the three-antenna feeding branch 710 and the isolation branch (the second isolator branch 612 and the fourth isolator branch 622), and between the three-antenna feeding branch and the metal ground 200, so that the magnetic coupling effect is excited. When the third antenna employs bottom feeding, the current distribution is as shown in fig. 16; when side feeding is employed, the current distribution of the antenna is as shown in fig. 17 and 18.

In some embodiments, the antenna radiation bandwidth is optimized by adjusting the size of the third antenna stub.

In one possible implementation, in combination with the space of the isolation slot 500, the third antenna branch may be designed to have a serpentine structure to increase the length, and the end of the third antenna branch may also be selected from a first position (as shown in fig. 19), a second position (as shown in fig. 20), a third position (as shown in fig. 21), and so on.

As shown in fig. 19, the three feeding branches 710 of the antenna extend along the second direction (Y direction in fig. 19), the first ends of the three feeding branches 710 of the antenna are in feeding connection with the bottom wall 530, the third antenna further includes a third coupling branch 740, a fourth coupling branch 750 and a fifth coupling branch 760, the third coupling branch 740 extends along the first direction (X direction in fig. 19), the fourth coupling branch 750 extends along the second direction (Y direction in fig. 19), and the fifth coupling branch 760 extends along the first direction (X direction in fig. 19). The second end of the antenna third feed branch 710 is vertically connected to the first end of the third coupling branch 740, the second end of the third coupling branch 740 is vertically connected to the first end of the fourth coupling branch 750, the second end of the third coupling branch 740 is vertically connected to the first end of the fifth coupling branch 760, and the second end of the fifth coupling branch 760 extends between the second isolation sub-branch 612 and the fourth isolation sub-branch 622, that is, the fifth coupling branch 760 is located at the first position.

As shown in fig. 20, the antenna three feeding branch 710 extends along the second direction (Y direction in fig. 20), the first end of the antenna three feeding branch 710 is in feeding connection with the bottom wall 530, the third antenna further includes a third coupling branch 740, a fourth coupling branch 750 and a fifth coupling branch 760, the third coupling branch 740 extends along the first direction (X direction in fig. 20), the fourth coupling branch 750 extends along the second direction (Y direction in fig. 20), and the fifth coupling branch 760 extends along the first direction (X direction in fig. 20). The second end of the third feeding branch 710 of the antenna is vertically connected to the first end of the third coupling branch 740, the second end of the third coupling branch 740 is vertically connected to the first end of the fourth coupling branch 750, the second end of the third coupling branch 740 is vertically connected to the first end of the fifth coupling branch 760, and the second end of the fifth coupling branch 760 extends between the second isolation branch 612 and the first sidewall 510, that is, the fifth coupling branch 760 is located at the second position.

As shown in fig. 21, the antenna three feeding branch 710 extends along the second direction (Y direction in fig. 21), the first end of the antenna three feeding branch 710 is in feeding connection with the bottom wall 530, the third antenna further includes a third coupling branch 740, a fourth coupling branch 750 and a fifth coupling branch 760, the third coupling branch 740 extends along the first direction (X direction in fig. 21), the fourth coupling branch 750 extends along the second direction (Y direction in fig. 21), and the fifth coupling branch 760 extends along the first direction (X direction in fig. 21). The second end of the antenna three feeding branch 710 is vertically connected to the first end of the third coupling branch 740, the second end of the third coupling branch 740 is vertically connected to the first end of the fourth coupling branch 750, the second end of the third coupling branch 740 is vertically connected to the first end of the fifth coupling branch 760, and the second end of the fifth coupling branch 760 extends between the fourth isolation sub-branch 622 and the second sidewall 520, that is, the fifth coupling branch 760 is located at the third position.

It should be noted that, the embodiment of the present invention provides an antenna apparatus, which is arranged on a printed circuit board, and adopts the design of adding parasitic branches beside the feed of an IFA antenna, so as to improve the bandwidth of the antenna, improve the radiation intensity of the antenna, and improve the radiation efficiency through the coupling effect between the parasitic branches and the feed; however, the antenna structure is not limited to the embodiment, and can be optimally designed according to the headroom and the size of the PCB.

1. The method is characterized in that a groove is formed at the current zero position of the metal ground, namely an isolation groove, so that an isolation structure can be added at the groove position while the radiation performance of the antenna is not influenced, and the isolation degree of an antenna system is improved;

2. the antenna isolation structure adopts two symmetrical metal branches, namely a first isolation branch and a second isolation branch, and an equivalent capacitance structure is formed by coupling the metal branches, so that the current path of the metal surface wave is changed, and the system isolation is optimized;

3. in the isolation slot structure, by combining the positions of the isolation branches, through adding a feeder line, namely three feeding branches of the antenna, in different modes of feeding at the bottom or feeding at the side of the isolation slot, by using magnetic coupling between the feeding branches and the isolation branches, under the condition that the size of the PCB is not changed, one path of antenna path is added, and the radiation bandwidth and the performance of the system antenna are improved.

Meanwhile, the embodiment is not limited to isolation optimization of the antennas with the same frequency, and for the problem of antenna isolation between different frequency bands and different systems faced by mobile terminals such as mobile phones, the isolation structure design of the embodiment can be carried out on a metal ground, so that mutual coupling between the antennas can be effectively reduced, and the performance of the system is optimized by improving the antenna isolation.

The antenna has the advantages of high isolation, small size, low price, large number of antennas and wider application range, and can be applied to various intelligent devices; meanwhile, by adding an equivalent capacitance isolation structure between the antennas, an additional capacitance resistance device is not needed, and the processing procedures are reduced; the added isolation structure can be reused as an antenna body, the number of the antennas is increased under the condition that the structure size is not changed, and the wireless coverage frequency and the use scene of the product are improved.

In a second aspect, the present invention further provides a terminal device, including any one of the antenna devices in the first aspect.

By slotting the isolation groove on the metal ground between the two antennas and adding the equivalent capacitance decoupling structure in the isolation groove, the isolation between the antennas can be effectively improved; meanwhile, the isolation structure body can be designed into an independent antenna in a magnetic coupling mode, a three-antenna system is realized and isolation is improved in a very small space, the requirement of a miniaturized multi-antenna high-isolation system is met, and the application range is wider. For example, the method can be applied to internet of things products such as smart homes, and can also be applied to terminal equipment such as mobile phones and tablets.

It will be apparent to those skilled in the art that various changes and modifications may be made to the embodiments of the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. An antenna device, comprising: the antenna comprises a substrate, and a metal ground, a first antenna and a second antenna which are arranged on the substrate;

the metal ground is provided with a first side edge, a second side edge and a third side edge, wherein the first side edge and the second side edge are oppositely arranged, and the third side edge is connected with the first side edge and the second side edge; the first antenna is positioned on one side, far away from the second side edge, of the metal ground and is connected with the first side edge; the second antenna is positioned on one side of the metal ground far away from the first side edge and connected with the second side edge;

2. The antenna device according to claim 1, wherein the isolation groove includes a first sidewall, a second sidewall, and a bottom wall connecting the first sidewall and the second sidewall, the first sidewall and the second sidewall each extending in a first direction, wherein the first direction is an extending direction of the first side edge;

3. The antenna device according to claim 2, wherein the first isolation branch comprises a first isolation sub-branch and a second isolation sub-branch, and the second isolation sub-branch is connected to the first sidewall through the first isolation sub-branch;

4. The antenna device of claim 3, wherein the second and fourth isolator sub-branches each extend along the first direction, and wherein the first and third isolator sub-branches extend along a second direction that is perpendicular to the first direction.

5. The antenna device of claim 4, further comprising a third antenna positioned within the isolation slot, the third antenna comprising an antenna triple feed stub, the first isolation stub, and the second isolation stub; and the first end of the three feeding branches of the antenna is connected with the metal ground feed, and the second end of the three feeding branches of the antenna is coupled with the first isolation branch and/or the second isolation branch.

6. The antenna device according to claim 5, wherein a first end of the antenna triple feed stub is in feed connection with the bottom wall, and a second end extends between the first isolation stub and the second isolation stub; or,

7. The antenna device of claim 5, wherein a first end of the antenna triple-feed stub is in feed connection with the first sidewall, the third antenna further comprises a first coupling stub, a second end of the antenna triple-feed stub is perpendicularly connected with the first end of the first coupling stub, the second end of the first coupling stub extends between the second isolation stub and the second sidewall, or,

8. The antenna device according to any of claims 1-7, characterized in that the first antenna and/or the second antenna comprises: the antenna comprises a feed branch, a first antenna branch, a second antenna branch, a third antenna branch, a grounding branch and a parasitic branch;

the first end of the feed branch is connected with the metal ground in a feed mode, the second end of the feed branch is connected with the first end of the first antenna branch and forms a first bending angle at the connection position, the second end of the first antenna branch is connected with the first end of the second antenna branch and forms a second bending angle at the connection position, the second end of the second antenna branch is connected with the first end of the third antenna branch and forms a third bending angle at the connection position, the second end of the third antenna branch is coupled with the first end of the parasitic branch, and the second end of the parasitic branch is connected with the metal ground;

9. The antenna device of claim 8, wherein the parasitic stub comprises a first parasitic sub-stub and a second parasitic sub-stub, wherein a second end of the second parasitic sub-stub is connected to the metal ground through the first parasitic sub-stub and forms a fifth bend angle at the connection.

10. A terminal device, characterized in that it comprises an antenna arrangement according to any of claims 1-9.