CN106935964B - Multi-antenna device and terminal equipment - Google Patents

Abstract

The embodiment of the present invention discloses a multi-antenna device, which includes a circuit board, a first antenna, a second antenna and a third antenna, the first antenna and the second antenna are arranged at one edge of the circuit board, and the second antenna The main beam directions of the first antenna and the second antenna are different. An isolation slot is provided between the first antenna and the second antenna for isolating mutual interference between the first antenna and the second antenna. The third antenna is disposed at the edge of the other side of the circuit board away from the first antenna and the second antenna. The third antenna includes a radiation body and a grounding branch. The radiation body is an IFA antenna. antenna. The embodiment of the present invention also provides a terminal device. By adopting the embodiment of the present invention, it is realized that multiple antennas are laid out on one circuit board, and the multiple antennas can be compatible under the premise of ensuring the performance of each antenna.

Description

Multi-antenna device and terminal equipment

technical field

The present invention relates to the technical field of antennas, in particular to a multi-antenna device and a terminal device having the multi-antenna device.

Background technique

Wireless terminal devices require many compatible modes and devices, leaving very little space for antenna design. For example, set-top boxes, as important terminal devices, the coverage quality of antennas is very important for user experience, so antenna design has an impact on product competitiveness. It goes without saying. The requirements of the era for antennas are becoming more and more stringent, the size of single boards is getting smaller and smaller, and the number of antennas is increasing, but the cost is getting lower and lower. The lower cost corresponds to cheaper chips and weaker signal analysis capabilities. Higher requirements are placed on the isolation between antennas. If the isolation cannot meet the requirements of product design specifications, it will easily cause signal interference between Wi-Fi and Bluetooth (Bluetooth, BT) antennas, thereby affecting customer experience.

Therefore, how to arrange multiple antennas in a limited space on a single board and make multiple antennas compatible on the premise of ensuring the performance of each antenna is an ongoing research direction in the industry.

Contents of the invention

The technical problem to be solved by the embodiments of the present invention is to provide a multi-antenna device and a terminal device with the multi-antenna device, which realizes the layout of multiple antennas on one circuit board, and ensures the performance of each antenna. , the multiple antennas are compatible.

In the first aspect, the embodiment of the present invention provides a multi-antenna device, including a circuit board, a first antenna, a second antenna, and a third antenna, the first antenna and the second antenna are arranged on the circuit board One edge, and the main beam directions of the first antenna and the second antenna are different; an isolation slot is provided between the first antenna and the second antenna for isolating the first antenna and the second antenna. Mutual interference between the second antennas; the third antenna is disposed at the edge of the other side of the circuit board away from the first antenna and the second antenna; the third antenna includes a radiating body and a grounding branch, the radiating body is an inverted-F antenna (Inverted-F Antenna, IFA), the grounding branch is connected to the grounding pin of the radiating body, and the grounding branch is used to make the third antenna The direction of the main beam does not point to the first antenna and the second antenna. The ground pin of the radiating body refers to the part connected to the ground plane on the circuit board.

By implementing the embodiments of the present invention, multiple antennas can be laid out on one circuit board, and the multiple antennas can be compatible under the premise of ensuring the performance of each antenna. Specifically, through the layout of the first antenna, the second antenna and the third antenna on the circuit board, and through the setting of the isolation slot between the first antenna and the second antenna, and the setting of the ground branch of the third antenna, The directions of the main beams of the three antennas are different, so that on the same circuit board, not only the performance of sending and receiving signals of each antenna can be guaranteed, but also the three antennas can be compatible with each other without interfering with each other.

The circuit board can be roughly rectangular, the first antenna and the second antenna are located at the first corner of the circuit board, the third antenna is located at the second corner of the circuit board, the first corner and the second corner can be opposite Adjacent corners can also be opposite corners. In one implementation manner, the first antenna and the second antenna are located on adjacent edges at a corner of the circuit board, and the directions of their main beams are 90 degrees different from each other.

In one embodiment, the first antenna includes a first body and a first branch, the first body is an IFA and includes a first radiation section, one end of the first radiation section is connected to the first antenna The other end of the first radiating section is a free end, the first branch bends and extends from the free end, and the first branch and the first radiating section form a Gap coupling.

In one embodiment, the first branch includes an extension section and a connection section, the connection section is connected between the free end of the first radiating section and one end of the extension section, and the extension section and the first A radiating section is linear and arranged opposite to each other. Specifically, the extension section and the connection section may be straight lines perpendicular to each other, and the extension section and the first radiating section may be parallel to each other. The first antenna can generate 2.4G signals through its own resonance, and can generate 5G signals through the second resonance formed between the first branch and the first radiation section. Therefore the first antenna is a dual frequency antenna.

In an implementation manner, the structure of the second antenna and the first antenna may be the same, and both the first antenna and the second antenna may be configured as WIFI antennas. The third antenna can be set as a BT antenna.

In one embodiment, the ground branch of the third antenna is a quarter-wavelength line. By setting the path length of the ground branch, it can ensure that the main beam direction of the third antenna is well controlled. time to achieve a more reasonable directional map avoidance.

Specifically, the grounding branch includes sequentially connecting a first section, a second section and a third section, the first section is set opposite to the third section, and the first section is far away from the second section. One end of the third section is connected to the ground pin of the radiation body, and the end of the third section away from the second section is a free end. The free end points to the ground leg of the radiating body.

In an implementation manner, the third antenna further includes an open branch connected to a free end of the radiation body, and the open branch is used to control a beam direction of the third antenna. In this embodiment, the open-circuit branch is located on the right side of the radiation body, and the open-circuit branch makes the main beam direction of the third antenna face to the right. In which direction the direction of the main beam is facing.

Specifically, the open branch is L-shaped and includes a first section and a second section, and the first section is vertically connected between the second section and the radiation body.

In one embodiment, a first ground branch and a second ground branch are formed on both sides of the isolation slot, and the first ground branch is used to reflect the electromagnetic signal generated by the first antenna and directed to the second antenna, The second ground branch is used to reflect the electromagnetic signal generated by the second antenna and directed to the first antenna. The isolation groove is a slot formed by etching on the ground layer of the circuit board, and the first ground branch and the second ground branch are formed at the same time after etching. The isolation groove is a quarter wavelength.

In one embodiment, the antenna device further includes a first coupling branch, the first coupling branch is located on a side facing the third antenna opposite the first antenna, and the first coupling branch is used for reflecting the electromagnetic signal generated by the first antenna and directed to the third antenna.

Specifically, the first coupling branch includes a bent section and a free section, the bent section is connected between the free section and the ground layer of the circuit board, and the free section points to the first antenna. The bending section includes a first section, a second section and a third section connected in sequence, the first section and the third section are arranged opposite to each other, and one end of the free section is connected to the third section away from One end of the second segment, the free end of the free segment points to the first antenna.

In one embodiment, the antenna device further includes a second coupling branch, the second coupling branch is located on a side of the second antenna away from the first antenna, and is used to reflect An electromagnetic signal that points electrons away from the inside of the circuit board. The structure of the second coupling branch can be identical to that of the first coupling branch. The second coupling branch includes a bent section and a free section. The free section of the second coupling branch points to the radiator of the second antenna. The bent section of the second branch is located between the free section and the ground layer of the circuit board. The setting of the second coupling branch can weaken the influence of the electromagnetic signal generated by the second antenna on other electronic components on the circuit board, and the side of the second coupling branch away from the second antenna can be provided with other electronic components, such as input and output interfaces Wait.

In a second aspect, an embodiment of the present invention provides a terminal device, including the antenna device described in any one of the foregoing implementation manners. The application of the antenna device in the terminal equipment is conducive to the development requirement of miniaturization of terminal installation size.

To sum up, in the embodiment of the present invention, the first antenna, the second antenna and the third antenna are arranged on the edge of the circuit board, and the third antenna is set away from the first antenna and the second antenna, and the grounding of the third antenna The branch controls the main beam direction of the third antenna, and controls the isolation between the first antenna and the second antenna through the isolation slot between the first antenna and the second antenna, so that the three antennas can be compatible on the same circuit board, In the working state, the main beam directions of the three antennas do not point to each other, so that the performance of the three antennas is guaranteed without interfering with each other.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the background technology, the following will describe the drawings that need to be used in the embodiments of the present invention or the background technology.

FIG. 1 is a schematic diagram of a multi-antenna device provided by an embodiment of the present invention;

FIG. 2 is an enlarged schematic view of part I (i.e., the first antenna) in the multi-antenna device shown in FIG. 1;

FIG. 3 is an enlarged schematic view of part II (i.e., the second antenna) in the multi-antenna device shown in FIG. 1;

FIG. 4 is an enlarged schematic diagram of part III (ie, the third antenna) in the multi-antenna device shown in FIG. 1;

Fig. 5 is a schematic diagram showing the distance between antennas in the antenna device provided by an embodiment of the present invention;

Fig. 6 is a schematic diagram showing return loss curves of each antenna in the antenna device provided by an embodiment of the present invention;

Fig. 7 is a schematic diagram showing insertion loss curves between antennas in an antenna device according to an embodiment of the present invention;

Fig. 8 is a beam pattern diagram of the first antenna and the second antenna in the antenna device provided by an embodiment of the present invention.

Detailed ways

Embodiments of the present invention will be described below with reference to the drawings in the embodiments of the present invention.

An embodiment of the present invention provides a multi-antenna device, which is applied to a terminal device, and the terminal device may be a set-top box, a router, a tablet computer, a mobile phone, and the like. Terminal equipment usually includes a variety of different functions, such as Wi-Fi function, Bluetooth (BT) function, etc. There are multiple antennas in the terminal equipment, which correspond to different functional modules for signal transmission, such as Wi-Fi antenna, BT antenna, etc. . The layout of the multiple antennas in the terminal device in the multi-antenna device provided by the embodiment example of the present invention can realize good isolation between lines, so that signals between the multiple antennas do not interfere with each other, thereby ensuring the signal transmitting and receiving performance of each antenna.

Referring to FIG. 1 , the multi-antenna device includes a circuit board 100 , a first antenna 10 , a second antenna 20 and a third antenna 30 . The circuit board 100 may be a main board in a terminal device. The circuit board 100 is provided with a ground layer 101, and an antenna placement area 102 is provided at the edge of the circuit board 100. In this embodiment, as shown in FIG. 1 , one of the circuit boards 100 An antenna deployment area 102 is provided at one corner, and an antenna deployment area 102 is provided at the other corner. A large-area ground layer is provided between the antenna deployment areas 102 at the two corners, so that both isolated from each other. Specifically, the ground layer 101 on the circuit board 100 is originally covered with the entire circuit board, and the antenna layout area 102 is formed at two corners by etching. In the embodiment of FIG. 1 , the antenna layout area 102 is set at the corner of the circuit board 100 , so as to satisfy other areas of the circuit board 100 to facilitate layout of electronic components. Of course, the antenna layout area 102 can also be set at other positions (non-corner positions) on the edge of the circuit board 100 .

In this embodiment, the first antenna 10 and the second antenna 20 are arranged at one edge of the circuit board 100, and the main beam directions of the first antenna 10 and the second antenna 20 are different. . An isolation slot 40 is provided between the first antenna 10 and the second antenna 20 for isolating mutual interference between the first antenna 10 and the second antenna 20 . In one embodiment, the first antenna 10 and the second antenna 20 are located on adjacent edges at a corner of the circuit board 100 , and the directions of their main beams are 90 degrees different from each other.

The third antenna 30 is disposed at the edge of the other side of the circuit board 100 away from the first antenna 10 and the second antenna 20 . The circuit board 100 can be roughly rectangular, the first antenna 10 and the second antenna 20 are located at the first corner of the circuit board 100, the third antenna 30 is located at the second corner of the circuit board 100, the first corner and the second side The corners may be adjacent corners or opposite corners. In the embodiment shown in FIG. 1 , the first corner and the second corner are arranged adjacently, so that all the antennas are concentrated on the left side of the circuit board 100, so that the right side of the circuit board 100 together with the first corner and the second corner The areas between the second corners jointly form a large-area antenna forbidden area, and the antenna forbidden area is used for arranging other electronic devices.

The third antenna 30 includes a radiation body 32 and a grounding branch 34, the radiation body 32 is an IFA, the grounding branch 34 is connected to the ground pin 322 of the radiation body 32, and the grounding branch 34 is used for Make the direction of the main beam of the third antenna 30 not point to the first antenna 10 and the second antenna 20 . The ground pin 322 of the radiation body 32 refers to a portion connected to the ground layer 101 on the circuit board 100 .

By implementing the embodiments of the present invention, multiple antennas can be laid out on one circuit board 100 , and the multiple antennas can be compatible under the premise of ensuring the performance of each antenna. Specifically, through the layout of the first antenna 10, the second antenna 20 and the third antenna 30 on the circuit board 100, and through the setting of the isolation groove 40 between the first antenna 10 and the second antenna 20, and the third The setting of the grounding branch 34 of the antenna 30 makes the main beam directions of the three antennas different, so that on the same circuit board 100, not only the performance of the transmitting and receiving signals of each antenna itself can be guaranteed, but also the three antennas can be compatible with each other. without interference.

IFA is also called inverted F antenna, its shape is an inverted "F", and IFA includes a ground point and a feed point. Usually, the radiation part of the IFA is in the shape of a flat plate or a straight line, and the IFA also includes a ground pin connected between the ground point and the radiation part, and a feed part connected between the feed point and the radiation part. The feeding point and the ground pin can be parallel to each other, and both can be perpendicular to the radiation part.

The specific structure of the first antenna 10 is as follows:

In one embodiment, the first antenna 10 includes a first body 12 and a first branch 14, the first body 12 is an IFA, the first body 12 includes a first radiation section 126, and the first radiation section One end of 126 is connected to the feeding point of the first antenna 10, the other end of the first radiating section 126 is a free end, the first branch 14 bends and extends from the free end, and the first branch A gap coupling is formed between the branch 14 and the first radiating section 126 .

Specifically, the first body 12 includes a first grounding pin 122, a first feeding section 124, a first radiating section 126 and a second radiating section 128, one end of the first grounding pin 122 is connected to the ground of the circuit board 100, the second The other end of a ground pin 122 is connected to one end of the second radiating section 128, one end of the first feeding section 124 is connected to the other end of the second radiating section 128, and the other end of the first feeding section 124 is the first The feeding point of the antenna 10 , one end of the first radiating section 126 is connected to the first feeding section 124 and the second radiating section 128 at the same time, and is collinear with the second radiating section 128 . The first feed section 124 is parallel to the first ground pin 122 .

In one embodiment, the first branch 14 includes an extension section 142 and a connection section 144, the connection section 144 is connected between the free end of the first radiating section 126 and one end of the extension section 142, the The extension section 142 and the first radiating section 126 are linear and opposite to each other. Specifically, the extension section 142 and the connecting section 144 may be straight lines perpendicular to each other, and the extension section 142 and the first radiation section 126 may be parallel to each other. Specifically, the length of the extension section 142 is greater than the sum of the lengths of the first radiating section 126 and the second radiating section 128 .

The first antenna 10 can generate 2.4G signals through its own resonance, and can generate 5G signals through the second resonance formed between the first branch 14 and the first radiation section 126 . Therefore, the first antenna 10 is a dual-band antenna.

In one embodiment, the structure of the second antenna 20 and the first antenna 10 may be the same, and the structure of the second antenna 20 is as follows.

The second antenna 20 includes a second body 22 and a second branch 24, the second body 22 is an IFA, the second body 22 includes a fourth radiation section 226, one end of the fourth radiation section 226 is connected to the first The feeding point of the second antenna 20, the other end of the fourth radiating section 226 is a free end, the second branch 24 bends and extends from the free end, and the second branch 24 and the first branch Slit coupling is formed between the four radiating segments 226 .

Specifically, the second body 22 includes a second ground pin 222, a second feed section 224, a third radiating section 228, and a fourth radiating section 226. One end of the second grounding pin 222 is connected to the ground of the circuit board 100, and the second ground pin 222 is connected to the ground of the circuit board 100. The other end of the two ground pins 222 is connected to one end of the third radiating section 228, one end of the second feeding section 224 is connected to the other end of the third radiating section 228, and the other end of the second feeding section 224 is the second end of the second feeding section 224. As the feeding point of the antenna 20 , one end of the fourth radiating section 226 is connected to the second feeding section 224 and the third radiating section 228 at the same time, and is collinear with the third radiating section 228 . The second feed segment 224 is parallel to the second ground pin 222 .

In one embodiment, the second branch 24 includes an extension section 242 and a connection section 244, the connection section 244 is connected between the free end of the fourth radiating section 226 and one end of the extension section 242, the The extension section 242 and the fourth radiating section 226 are straight and opposite to each other. Specifically, the extension section 242 and the connection section 244 may be straight lines perpendicular to each other, and the extension section 242 and the fourth radiating section 226 may be parallel to each other. Specifically, the length of the extension section 242 is greater than the sum of the lengths of the third radiating section 228 and the fourth radiating section 226 .

In one embodiment, the extension direction of the extension section of the first branch 14 of the first antenna 10 is 90 degrees different from the extension direction of the extension section of the second branch 24 . That is to say, the setting of the first antenna 10 and the setting of the second direction differ by 90 degrees, so that the main beam direction of the first antenna 10 and the main beam direction of the second direction differ by 90 degrees. In the embodiment shown in FIG. 1 , The main beam of the first antenna 10 is directed to the left, and the main beam of the second antenna 20 is directed downward.

The structure of the third antenna 30 is as follows.

Referring to Fig. 4, the radiation body 32 of the third antenna 30 includes a ground pin 322, a feed section 323 and a radiation portion 326, one end of the radiation portion 326 is connected to the ground pin 322, and the other end of the radiation portion 326 is the free end of the radiation body 32. In one embodiment, the radiating part 326 is linear, and the ground pin 322 and the feeding section 324 are arranged in parallel and are vertically connected to the radiating part 326 . The ground branch 34 is located at one side of the ground pin 322 of the radiation body 32 .

In one embodiment, the ground branch 34 of the third antenna 30 is a quarter-wavelength line. By setting the path length of the ground branch 34, it can ensure that the main beam direction of the third antenna 30 is well controlled. Between the three antennas, a more reasonable pattern avoidance is realized.

Specifically, the ground branch 34 includes a first segment 324, a second segment 344 and a third segment 346 connected in sequence, the first segment 342 is set opposite to the third segment 326, and the first segment 342 An end far from the second segment 344 is connected to the ground pin 322 of the radiation body 32 , and an end of the third segment 346 far from the second segment 344 is a free end. The free end of the third segment 346 points to the ground pin 322 of the radiation body 32 .

In one embodiment, the ground branch 34 is connected to the junction of the ground leg 322 and the radiation portion 326 . The first segment 342 of the ground branch 34 and the radiating part 326 may be collinearly arranged. In other implementations, the ground branch 34 may also be connected to other positions of the ground pin 322 .

In one embodiment, the third antenna 30 further includes an open branch 36, the open branch 36 is connected to the free end of the radiation body 32, that is, the open branch 36 is connected to the radiating section 326 away from the ground pin 322 at one end. The open branch 36 is used to control the beam direction of the third antenna 30 . In this embodiment, the open branch 36 is located on the right side of the radiation body 32, and the open branch 36 makes the main beam direction of the third antenna 30 face to the right, that is to say, which side of the radiation body 32 the open branch 36 is located on. Which direction the main beam of the third antenna 30 is directed to.

Specifically, the open branch is L-shaped, including a first section 362 and a second section 364 , and the first section 362 is vertically connected between the second section 364 and the radiation body 32 .

In one embodiment, a first ground branch 34 and a second ground branch 34 are further provided between the first antenna 10 and the second antenna 20 . The isolation groove 40 is a slot formed by etching on the ground layer of the circuit board 100. After etching, a first ground branch and a second ground branch are formed at the same time. The first ground branch is used to reflect the first ground branch. An electromagnetic signal generated by an antenna 10 directed to the second antenna 20 , and the second ground branch is used to reflect an electromagnetic signal generated by the second antenna 20 directed to the first antenna 10 . Specifically, the isolation groove 40 is a quarter wavelength.

Please refer to FIG. 2 , in an implementation manner, the antenna device further includes a first coupling branch 60, the first coupling branch 60 is located on the side of the first antenna 10 facing the third antenna 30, The first coupling branch 60 is used to reflect the electromagnetic signal generated by the first antenna 10 and directed to the third antenna 30 .

Specifically, the first coupling branch 60 includes a bent section 62 and a free section 64. In one embodiment, the bent section 62 is n-shaped. The bent section 62 is connected between the free section 64 and the ground layer 101 of the circuit board 100 , and the free section 64 points to the first antenna 10 . The bent section 62 includes a first section 621, a second section 622 and a third section 623 connected in sequence, the first section 621 and the third section 623 are arranged opposite to each other, and one end of the free section 64 is connected to To the end of the third section 623 away from the second section 622 , the free end of the free section 64 points to the first antenna 10 . Specifically, the first segment 621 is parallel to the third segment 623 , and the second segment 622 is vertically connected between the first segment 621 and the third segment 623 .

Please refer to FIG. 3 , in an implementation manner, the antenna device further includes a second coupling branch 70, the second coupling branch 70 is located on the side of the second antenna 20 away from the first antenna 10, for To reflect the electromagnetic signal generated by the second antenna 20 and directed away from the electrons inside the circuit board 100 . The structure of the second coupling branch 70 may be the same as that of the first coupling branch 60 . The second coupling branch 70 includes a bent section 72 and a free section 74, the free section 74 of the second coupling branch 70 points to the radiator of the second antenna 20, and the bent section 72 of the second coupling branch 70 is located at the free section 74 and the ground layer of the circuit board 100, the setting of the second coupling branch 70 can weaken the influence of the electromagnetic signal generated by the second antenna 20 on other electronic components on the circuit board 100, and the second coupling branch 70 is far away from the second One side of the antenna 20 may be provided with other electronic components, such as input and output interfaces. In one embodiment, the bent section 72 of the second coupling branch 70 has the same structure as the bent section 62 of the first coupling branch 60 .

Both the first antenna 10 and the second antenna 20 can be set as WIFI antennas. The third antenna 30 may be set as a BT antenna.

Please refer to Fig. 5, the distance D1 between the first antenna 10 and the second antenna 20 is about 30mm or less, the distance D2 between the first antenna 10 and the third antenna 30 is greater than or equal to 60mm, and the distance between the antennas refers to is the straight-line distance between the feed points of the antennas. The distance D2 between the second antenna 20 and the third antenna 30 is greater than the distance D1 between the first antenna 10 and the third antenna 30 .

Please refer to FIG. 6 , which is a schematic diagram of the return loss of the first antenna 10 , the second antenna 20 and the third antenna. Wherein S(1,1) represents the return loss curve of the first antenna 10 ; S(2,2) represents the return loss curve of the second antenna 20 ; S(3,3) represents the return loss curve of the third antenna 30 . It can be seen from Figure 6 that the return loss of each antenna basically meets the conventional requirement of -10dB, and the industry often uses -10dB as the standard for antenna return loss.

Please refer to Figure 7, which shows a schematic diagram of the insertion loss between the antennas. 1 represents the first antenna 10 , 2 represents the second antenna 20 , and 3 represents the third antenna 30 . dB(S(2,1)) represents the insertion loss between the second antenna and the first antenna. dB(S(3,1)) represents the insertion loss between the third antenna and the first antenna, and dB(S(3,2)) represents the insertion loss between the third antenna and the second antenna. Insertion loss is the isolation. The value of the isolation directly expresses the degree of mutual influence between the antennas. The smaller the isolation [the larger the absolute value], the smaller the influence between the antennas. The acceptance capability of the industry's chips is probably the isolation between Wi-Fi The standard is -15dB; the isolation standard between Wi-Fi and BT is -25dB. The insertion loss diagram shown in FIG. 7 shows that the embodiment of the present invention can satisfy the resolution capability of most chips.

Please refer to Figure 8, which shows the beam pattern of the first antenna and the second antenna. Both the first antenna and the second antenna are WIFI antennas. It can be seen from the figure that the horizontal plane of the two WIFI antennas (that is, the plane where the circuit board is located) ) is not greatly affected, and can basically achieve a uniform coverage effect. The first antenna and the second antenna in the multi-antenna device provided in the embodiment of the present application include two frequency bands of 2400-2500MHz/5150-5850MHz, and the third antenna includes a frequency band of 2400-2500MHz, so multiple antennas can be realized within the range of 2400-2500MHz. Antenna compatible.

The multi-antenna device provided by the embodiment of the present invention is applied in terminal equipment, which is conducive to the development requirement of miniaturization of terminal installation size.

In summary, by implementing the embodiment of the present invention, the first antenna 10, the second antenna 20 and the third antenna 30 are arranged on the edge of the circuit board 100, and the third antenna 30 is far away from the first antenna 10 and the second antenna 20, the main beam direction of the third antenna 30 is controlled by the ground branch 34 of the third antenna 30, and the distance between the first antenna 10 and the second antenna 20 is controlled by the isolation slot 40 between the first antenna 10 and the second antenna 20. The isolation between them makes the three antennas compatible on the same circuit board 100. In the working state, the main beam directions of the three antennas do not point to each other, so that the performance of the three antennas is guaranteed without interfering with each other. By controlling the antenna pattern, high isolation is achieved, which satisfies the analysis capability of the chip (WIFI chip), ensures the use of low-cost chips, and does not affect the user experience. The multi-antenna device provided by the embodiment of the present invention can not only meet the requirement of isolation, but also can realize relatively uniform coverage of wireless signals on the horizontal plane, and ensure the quality of throughput at each angle.

Claims (11)

1. A multi-antenna device is characterized by comprising a circuit board, a first antenna, a second antenna and a third antenna,

the first antenna and the second antenna are arranged at one side edge of the circuit board, and the main beam directions of the first antenna and the second antenna are different;

an isolation groove is arranged between the first antenna and the second antenna and used for isolating mutual interference between the first antenna and the second antenna;

the third antenna is arranged at the edge of the other side of the circuit board away from the first antenna and the second antenna;

the third Antenna comprises a radiation main body and a grounding branch, wherein the radiation main body is an Inverted-F Antenna (IFA), the grounding branch is connected to a grounding pin of the radiation main body, and the grounding branch is used for enabling a main beam of the third Antenna not to point to the first Antenna and the second Antenna; the grounding branch circuit comprises a first section, a second section and a third section which are sequentially connected, the first section and the third section are oppositely arranged, one end, far away from the second section, of the first section is connected to the grounding pin of the radiation main body, one end, far away from the second section, of the third section is a free end, and the third section extends towards the grounding pin.

2. The multiple antenna device of claim 1, wherein the first antenna includes a first body and a first branch, the first body is an IFA and includes a first radiating section, one end of the first radiating section is connected to a feeding point of the first antenna, the other end of the first radiating section is a free end, the first branch extends from the free end in a bent manner, and a slot coupling is formed between the first branch and the first radiating section.

3. The multiple antenna device according to claim 2, wherein the first branch includes an extension section and a connection section, the connection section is connected between a free end of the first radiation section and one end of the extension section, and the extension section and the first radiation section are both linear and are disposed opposite to each other.

4. The multiple antenna device of claim 1, wherein the ground branch is a quarter-wave line.

5. The multiple antenna device of claim 1, wherein the third antenna further comprises an open branch connected to the free end of the radiating body, the open branch for controlling a beam direction of the third antenna.

6. The multiple antenna device of claim 5, wherein the open branch is L-shaped and includes a first segment and a second segment, the first segment being connected vertically between the second segment and the radiating body.

7. The antenna device according to claim 1, wherein a first ground branch for reflecting the electromagnetic signal generated by the first antenna and directed to the second antenna and a second ground branch for reflecting the electromagnetic signal generated by the second antenna and directed to the first antenna are formed on both sides of the isolation groove.

8. The antenna device of claim 7, wherein the isolation slot is a quarter wavelength.

9. The antenna device of claim 1, further comprising a first coupling branch located on a side of the first antenna facing the third antenna, the first coupling branch being configured to reflect an electromagnetic signal generated by the first antenna and directed toward the third antenna.

10. The antenna arrangement according to claim 9, wherein the first coupling branch comprises a bent section and a free section, the bent section being connected between the free section and a ground layer of the circuit board, the free section being directed towards the first antenna.

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